Olav Kristianslund

• Anitha, Venugopal; Nallasamy, Nambi; Christy, Josephine S.; Kristianslund, Olav; Stephenson, Kirk A.J. & Hashemi, Hassan [Vis alle 8 forfattere av denne artikkelen] (2025). Understanding Keratoconus in Down Syndrome: From Etiology to Management–A Narrative Review. Clinical Ophthalmology. ISSN 1177-5467. 19, s. 4925–4939. doi: 10.2147/OPTH.S556378. Fulltekst i vitenarkiv Vis sammendrag

  Paediatricians are often the first to identify children with DS and their awareness on associated ocular comorbidities, play a critical role in ensuring timely referral to general ophthalmologists for diagnosis and management. Among these, keratoconus (KC) has a significantly higher prevalence among Down syndrome (DS) compared to the general population. The awareness and understanding of KC, is essential for preventing vision loss. This review summarizes the current understanding of KC in DS, on epidemiology, pathophysiology, diagnostic challenges, and management. The children with DS, have thinner and steeper corneas since birth, complicates the diagnostic and management protocols. Poor cooperation of the children for imaging, compromised scan qualities, need for sedation and repeatability of scans poses diagnostic challenges. Early intervention with corneal cross-linking (CXL) is shown to be effective in halting disease progression. The surgical options in advanced cases, carry higher risks in DS patients due to factors such as eye rubbing, increased infection rates, and challenges in postoperative compliance. Managing KC in DS requires a comprehensive approach involving early referral by Paediatricians, pre-emptive diagnosis, and timely intervention with CXL to prevent disease progression. Future research should focus on preclinical gene prediction and developing standardized screening protocols for KC among DS to prevent vision loss and thereby improve quality of life among them.

• Sverstad, Alexander; Møller, Jens Riis; Virgili, Gianni; Azuara-Blanco, Augusto; Freiberg, Josefine & Ahrensberg, Simone [Vis alle 9 forfattere av denne artikkelen] (2025). Central Contrast Sensitivity as an Outcome Measure in Randomized Controlled Trials in Glaucoma—A Systematic Review. Life. 15(7). doi: 10.3390/life15071043. Fulltekst i vitenarkiv
• Thorbjørnsen, Bjarne Løberg; Velle-Skretteberg, Marthe Andrea; Thorsrud, Andreas; Sæthre, Marit; Østern, Atle Einar & Drolsum, Liv Kari [Vis alle 7 forfattere av denne artikkelen] (2025). Infectious keratitis after corneal cross-linking: A retrospective case series. Cornea. ISSN 0277-3740. s. 1–6. doi: https:/journals.lww.com/corneajrnl/fulltext/9900/infectious_keratitis_after_corneal_cross_linking_.899.aspx. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To evaluate the risk of infectious keratitis after corneal cross-linking (CXL) in eyes with corneal ectasia. Methods: In this retrospective case series, we reviewed the medical records of patients with a diagnosis code for keratitis over a 6-month period after all CXLs performed in the Department of Ophthalmology at Oslo University Hospital from 2007 to 2020. To compare our results with the existing literature, we reviewed studies evaluating the risk of keratitis after CXL. Results: A total of 1809 CXLs were performed in our department during the study period. The annual number of CXLs increased from 3 in 2007 to 219 in 2020. We identified 11 (0.6%) cases registered with a keratitis code within 6 months after CXL, of which the physician considered five (0.3%, 95% CI: 0.1%–0.6%) to be a procedure-related infectious keratitis. The microbiological agents were Staphylococcus aureus (n=3), Acanthamoebae (n=1), or unknown (n=1). The literature review identified 23 relevant studies that reported infectious keratitis in 0%–2.6% of eyes after CXL treatment. To our knowledge, this is the first Scandinavian study to report the risk of infectious keratitis after CXL and the largest European study. Conclusions: We found a low incidence of infectious keratitis following CXL. Our rate was comparable to that reported in the literature, indicating a low risk of this complication in eyes with corneal ectasia treated with CXL.

• Bjerkreim, Hilde; Thorbjørnsen, Bjarne Løberg; Nærland, Terje; Drolsum, Liv Kari & Kristianslund, Olav (2025). Nationwide study of the association between keratoconus and autism spectrum disorder. Journal of cataract and refractive surgery. ISSN 0886-3350. 51(12), s. 1057–1062. doi: 10.1097/j.jcrs.0000000000001740. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To examine whether there was an association between keratoconus and autism spectrum disorder (ASD) in Norway and compare with the general population. Setting: The total population of Norway, including all individuals with ASD and keratoconus. Design: Cross-sectional epidemiological study. Methods: Data were obtained from the Norwegian Patient Registry, which provides information from all publicly funded specialist care. The keratoconus prevalence among persons with ASD was estimated from the total number of individuals with keratoconus in the period 2010-2019 and compared with the prevalence in the general population of Norway during the same period. Results: A population-based sample in Norway identified 23 763 persons with ASD, equivalent to 0.5% of the population, and of these, 115 (0.5%) had a diagnosis of keratoconus. The average age at keratoconus diagnosis among individuals with ASD was 27.3 years, and 83.5% of those diagnosed with both ASD and keratoconus were men. During the same period, the prevalence of keratoconus in the general population of Norway was 0.2%, resulting in an odds ratio of 2.5 (95% CI 2.0-3.0). Conclusions: Based on our findings, people with ASD have significantly higher prevalence of keratoconus compared with the general population of Norway. This implicates that one should have increased awareness for keratoconus and low threshold for corneal tomography in patients with ASD.

• Sverstad, Alexander; Helland-Hansen, Bjørn Andre; Kristianslund, Olav; Kolko, Miriam; Larsen, Stig Einride & Petrovski, Goran (2025). Eye-tracking biomarkers for glaucoma based on saccadic reaction time: a controlled clinical study. Frontiers in Ophthalmology. 5. doi: 10.3389/fopht.2025.1636911. Fulltekst i vitenarkiv Vis sammendrag

  Purpose Evaluate the validity and reliability of saccadic reaction time (SRT)-based variables obtained using the novel eye-tracking device Bulbicam (BCAM) in differentiating early-to-moderate glaucoma (GLA) from healthy controls (HCs) and to identify potential biomarkers for GLA. Methods A controlled clinical study was conducted, involving 18 GLA-patients, and 18 age-matched HCs. Participants underwent BCAM’s visual field (VF) test, which measures SRT at 58 symmetrically arranged locations with 6° spacing. Variables were analysed for group differences, within- and between-patient repeatability, and stability. To evaluate their potential as biomarkers, VF locations were aggregated into clusters, quadrants, hemifields, and whole VF analyses. Results Significant SRT differences (p ≤ 0.05) were observed between GLA and HC in 44 of 58 locations in the worst eye and 42 of 58 in the best eye. Eight out of ten clusters met the criteria for BCAM biomarkers having significant group differences, sufficient within- and between-patient repeatability, and adequate stability. All quadrants demonstrated excellent stability and repeatability thereby qualifying as biomarkers. Hemifield SRTs were reliable, however, the absolute difference between hemifields showed poor within-participant repeatability. The mean and standard deviation of SRT for the whole VF were identified as significant biomarkers with excellent stability. Conclusions The majority of SRT variables are capable of differentiate glaucomatous eyes from HC while maintaining sufficient reliability and stability for clinical application. 19 of 22 BCAM VF test variables were found to be potential GLA-biomarkers. Clinical Trial Registration https://clinicaltrials.gov/ , identifier NCT05449041.

• Five, Christian K.; Hasselberg, Nina Eide; Bjerkreim, Hilde; Aaserud, Linda Soon Ah Tangen; Castrini, Anna Isotta & Bugge, Cecilie [Vis alle 11 forfattere av denne artikkelen] (2025). Revisiting the Link Between Keratoconus and Mitral Valve Prolapse. Cardiogenetics. ISSN 2035-8253. 15(1). doi: 10.3390/cardiogenetics15010004. Fulltekst i vitenarkiv Vis sammendrag

  Keratoconus is a progressive eye disease that results in thinning of the cornea, leading to visual impairment. Mitral valve prolapse (MVP) is a common disorder affecting around 2–4% of the general population. Previous studies have found an overrepresentation of MVP in individuals with keratoconus, with a prevalence of 38–65%, suggesting a shared underlying mechanism. In this case-control study, patients with keratoconus were enrolled from a quality and research registry. They were examined by a 2D echocardiography to identify if they had MVP, billowing or normal mitral leaflets. Controls were matched from the population-based Trøndelag Health Study. Patients and controls underwent a detailed echocardiographic examination to detect abnormal mitral valves. We included 101 patients (age 33 [IQR 29–40], 75% male) with keratoconus and 101 matched individuals. MVP was found in 2 (2%), while billowing was found in 5 (5%) of keratoconus patients. No significant association was found between keratoconus and the prevalence of MVP or billowing compared to the control group. Moreover, no associations were found between severity of keratoconus with presence of MVP nor with billowing of the mitral valves. We could not confirm the previously reported association between keratoconus and MVP, suggesting that routine screening for MVP in keratoconus patients may not be warranted. However, we cannot rule out the possibility of an association in other gender, age and ethnic groups different than ours.

• Sverstad, Alexander; Kristianslund, Olav; Petrovski, Goran; Moe, Morten Carsten & Jørstad, Øystein Kalsnes (2024). A proof-of-concept study of a prototype needle that mitigates intraocular pressure rise following intravitreal injection. International Journal of Retina and Vitreous (IJRV). 10(1). doi: 10.1186/s40942-024-00590-0. Fulltekst i vitenarkiv Vis sammendrag

  Purpose To determine the feasibility of a prototype needle that enhances vitreous reflux (VR) to control intraocular pressure (IOP) in intravitreal injection (IVI). Methods We created an eye model to compare IVI using a standard 30-G needle with four different versions of a 30-G prototype needle with one to four surface grooves that enhanced VR. We injected 50, 70, and 100 µl saline through porcine sclera or 460-µm-thick rubber and measured the peak and 3-second pressure before we extracted the needle and measured the 10-second pressure. Results 50-µl injection through sclera with the standard needle resulted in mean (SD) pressure of 58.6 (3.8) mmHg at peak, 52.8 (4.7) mmHg at 3 s, and 39.6 (18.0) mmHg at 10 s. The prototype needle lowered the pressure; four grooves resulted in mean (SD) pressure of 29.4 (5.6) mmHg at peak, 22.0 (3.7) mmHg at 3 s, and 7.2 (6.6) mmHg at 10 s. 70-µl and 100-µl injections through sclera with the standard needle resulted in mean (SD) pressure of 68.8 (3.6) and 86.0 (6.0) mmHg at peak. Similar to 50-µl injection, the prototype needle lowered the pressure for 70-µl and 100-µl injections. At 10 s, we observed varying leakage at the injection site for sclera but not for rubber. Conclusions The study provides proof of concept for a needle design for which surface grooves enhance VR and counteract the effect of IVI on IOP. The safety and efficacy of the prototype needle must be studied further in a clinical trial.

• Sund, Martin Harvey; Slettedal, Jon Klokk; Sæthre, Marit; Haslev, Hans Petter; Kristianslund, Olav & Østern, Atle Einar [Vis alle 7 forfattere av denne artikkelen] (2024). Incidence, risk factors, and patient characteristics in severe contact lens-related microbial keratitis. Acta Ophthalmologica. ISSN 1755-375X. 103(3), s. 289–294. doi: 10.1111/aos.16796. Fulltekst i vitenarkiv Vis sammendrag

  Purpose The aim of the present study was to determine the incidence, patient characteristics, and risk factors for severe, contact lens-related keratitis in patients in need of hospitalization. Methods Keratitis was defined as severe when the disease required hospitalization. All patients with contact lens-related keratitis hospitalized at our department between 1 January 2018 and 31 December 2020 were interviewed with a questionnaire, about their use of contact lenses and knowledge of complications. Clinical information was collected from the medical records. Results A total of 41 patients (42 eyes) were hospitalized with severe keratitis during the 3-year period. The yearly incidence was 2.52 per 10 000 contact lens users over the age of 15 for extended-wear lenses used overnight, and 0.52 per 10 000 for users of daily disposable contact lenses. Pseudomonas aeruginosa was the most frequently isolated microbe. The median age was 50 years (range 15–66 years). Twenty-three patients (56%) were female, 28 patients (66%) used extended-wear contact lenses and 12 patients (29%) used daily disposable lenses. Nineteen patients (45%) admitted improper use. The median duration of contact lens use was 11.5 years. Only 15 patients (37%) had knowledge of keratitis as a potential complication. Conclusion Most patients were experienced contact lens users. Users of extended-wear contact lenses worn overnight had a significantly higher risk of severe microbial keratitis. More focus on information and education of the risk of keratitis in contact lens users is needed.

• HAGEM, ANNE MARIE; Thorsrud, Andreas; Sæthre, Marit; Sandvik, Gunhild Falleth; Kristianslund, Olav & Drolsum, Liv Kari (2023). Dramatic Reduction in Corneal Transplants for Keratoconus 15 Years After the Introduction of Corneal Collagen Crosslinking. Cornea. ISSN 0277-3740. 43(4), s. 437–442. doi: 10.1097/ICO.0000000000003401. Fulltekst i vitenarkiv
• Bisevac, Jovana; Moe, Morten Carsten; Drolsum, Liv Kari; Kristianslund, Olav; Petrovski, Goran & noer, agate (2023). A Novel Technique of Amniotic Membrane Preparation Mimicking Limbal Epithelial Crypts Enhances the Number of Progenitor Cells upon Expansion. Cells. 12(5). doi: 10.3390/cells12050738. Fulltekst i vitenarkiv Vis sammendrag

  We aimed to investigate whether a novel technique of human amniotic membrane (HAM) preparation that mimics the crypts in the limbus enhances the number of progenitor cells cultured ex vivo. The HAMs were sutured on polyester membrane (1) standardly, to obtain a flat HAM surface, or (2) loosely, achieving the radial folding to mimic crypts in the limbus. Immunohistochemistry was used to demonstrate a higher number of cells positive for progenitor markers p63α (37.56 ± 3.34% vs. 62.53 ± 3.32%, p = 0.01) and SOX9 (35.53 ± 0.96% vs. 43.23 ± 2.32%, p = 0.04), proliferation marker Ki-67 (8.43 ± 0.38 % vs. 22.38 ± 1.95 %, p = 0.002) in the crypt-like HAMs vs. flat HAMs, while no difference was found for the quiescence marker CEBPD (22.99 ± 2.96% vs. 30.49 ± 3.33 %, p = 0.17). Most of the cells stained negative for the corneal epithelial differentiation marker KRT3/12, and some were positive for N-cadherin in the crypt-like structures, but there was no difference in staining for E-cadherin and CX43 in crypt-like HAMs vs. flat HAMs. This novel HAM preparation method enhanced the number of progenitor cells expanded in the crypt-like HAM compared to cultures on the conventional flat HAM.

• Agra, Lydianne Lumack do Monte; Sverstad, Alexander; Chagas, Thiago A; Araujo, Rodrigo H.; Oliveira, Larissa & Kristianslund, Olav [Vis alle 11 forfattere av denne artikkelen] (2023). Accuracy, Precision, and Residual Volume of Commonly Used Syringes for Intravitreal Injections and the Impact on Intraocular Pressure. Ophthalmology Retina. ISSN 2468-7219. 7(10), s. 892–900. doi: 10.1016/j.oret.2023.06.003. Fulltekst i vitenarkiv Vis sammendrag

  Purpose To compare accuracy, precision, and residual volume of commonly used syringes for intravitreal injections (IVIs) and to assess the intraocular pressure (IOP) rise by variations in volumes delivered. Design Experimental laboratory study. Subjects No subjects were involved in this study. Methods We tested 8 syringe models with 2 different needle setups, with 2 different solutions (distilled water or glycerin) and target volumes (50 and 70 μL). To obtain the delivered and residual volumes, we weighed the syringe-needle setups with scale before liquid withdrawal, with liquid, and after liquid release. We also created an experimental eye model to determine the transient rise in IOP following stepwise 10-μL increases in injection volumes. Main Outcome Measures Delivered and residual volumes, IOP rise. Results We tested a total of 600 syringe-needle setups. Becton Dickinson (BD) Ultra-Fine (0.34 ± 0.28 μL), Zero Residual (1.53 ± 1.15 μL), and Zero Residual Silicone Oil-free (1.40 ± 1.16 μL) syringes showed the lowest residual volume (P < 0.001) in comparison with the others (range: 24.86 ± 1.78 μL for Injekt-F to 51.97 ± 3.37 μL for Omnifix-F). The most accurate setups were (percentage deviation from target volume): Zero Residual Silicone Oil-free (+ 0.70%), Zero Residual 0.3 ml (+ 4.49%), BD Ultra-Fine (+ 7.83%), Injekt-F (9.42%), Norm-Ject (+ 15.88%), Omnifix-F (+ 16.96%), BD Plastipak Brazil (+17.96%), and BD Plastipak Spain syringes (+ 19.41%). There was a statistically significant difference between the Zero Residual Silicone Oil-free syringe and all other syringes (P < 0.0001), except for the Zero Residual 0.3-ml syringe (P = 0.029). The coefficient of variation was low for all syringes. The modeled IOP rise ranged from 32.3 (standard deviation [SD], 1.4) mmHg for 20-μL injection volume to 76.5 (SD, 1.0) mmHg for 80-μL injection volume. For the standard 50-μL injection volume, the peak pressure was 50.7 (SD, 0.1) mmHg, and the pressure rise duration was 28 (SD, 2) minutes. Conclusions There were significant differences in accuracy and residual volume between syringes, whereas they showed a high precision. Volume excess results in a considerable increase in IOP rise after injection. These findings may provide a relevant overview to clinicians and to both device and drug manufacturers regarding pharmacoeconomic, safety, and efficacy issues.

• Bøhler, Anders Djupesland; Traustadottir, Valgerdur Dora; HAGEM, ANNE MARIE; Tønseth, Turid Skei; Drolsum, Liv Kari & Kristianslund, Olav (2023). Hypotony in the early postoperative period after MicroShunt implantation versus trabeculectomy: A registry study. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.15727. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Purpose A comparison of the safety and efficacy of the MicroShunt versus trabeculectomy in the early postoperative period, with a particular focus on hypotony. Methods In this registry study, we evaluated 200 eyes of 200 glaucoma patients who underwent filtration surgery at Oslo University Hospital between 2017 and 2021. Of these patients, 100 had a Preserflo MicroShunt (Santen) implantation and 100 had a trabeculectomy procedure. The patients were examined per standard hospital protocol after filtration surgery. Data were extracted from the 4‐ and 8‐week visits. We defined hypotony as intraocular pressure (IOP) &lt; 6 mmHg. Results The mean preoperative IOP was 20.6 ± 7.1 mmHg in the MicroShunt group and 21.6 ± 7.1 mmHg in the trabeculectomy group, and the patients used a mean of 3.0 ± 0.9 and 3.1 ± 0.9 glaucoma medications, respectively. After 8 weeks, IOP was reduced to 10.4 ± 5.4 mmHg and 11.3 ± 4.6 mmHg, respectively ( p  = 0.23). During the early postoperative period, hypotony was registered in 63% of the MicroShunt patients and in 21% of the patients in the trabeculectomy group ( p  &lt; 0.001); and 11% and 1%, respectively, of the patients developed choroidal detachments ( p  &lt; 0.003). One patient in the MicroShunt group required reoperation due to hypotony. Conclusions In this registry study, we found that the Preserflo MicroShunt and trabeculectomy had equally satisfactory IOP‐lowering effects during the early postoperative period. In this same period, a high number of patients in the MicroShunt group developed hypotony.

• Medin, Ingvild Helle; Kure, Ingeborg Slørdahl Hjort; Dalby, Marius; Kristianslund, Olav & Drolsum, Liv Kari (2023). Inflammatory reaction in eyes with late in-the-bag intraocular lens dislocation. Acta Ophthalmologica. ISSN 1755-375X. 102(3). doi: 10.1111/aos.15720. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To investigate the inflammatory reaction in eyes with late in-the-bag intraocular lens (IOL) dislocation. Methods: This prospective clinical study with fellow-eye comparison consists of 76 of the patients (76 eyes) with late in-the-bag IOL dislocation enrolled in the LION trial. The main outcome measure was anterior chamber flare before surgery measured with a laser flare meter in photon counts per millisecond (pc/ms). The dislocation was graded as 1 (small: optic still covering the visual axis), 2 (optic equator close to the visual axis) or 3 (optic decentred beyond the visual axis, but the IOL–capsule complex partly visible in the pupillary area). The secondary aim was to compare intraocular pressure (IOP) before surgery. Results: Flare levels before surgery were significantly higher in the dislocation eyes than in the fellow eyes with a median flare of 21.5 (range 5.4–135.7) pc/ms versus 14.1 (2.0–42.9) pc/ms, respectively (p ˂ 0.001). A regression analysis of log-transformed flare values showed that the dislocation eyes had a non-significant tendency towards higher flare in dislocation grade 1 with a median flare of 24.6 (5.4–135.7) pc/ms compared to grade 2; 19.6 (6.5–41.5) pc/ms (p = 0.06), and no significant difference compared to grade 3; 19.4 (10.2–53.5) pc/ms (p = 0.47). The IOP was significantly higher in the dislocation eyes than in the fellow eyes (p ˂ 0.001). Conclusions: Eyes with late in-the-bag IOL dislocation had increased flare levels compared to their fellow eyes. This suggests that inflammation is part of the clinical picture of late in-the-bag IOL dislocation.

• Sand, Mari Kathrine; Cholidis, Symira; Kristianslund, Olav & Drolsum, Liv Kari (2023). Bag-in-the-lens intraocular lens implantation before 12 weeks of age in congenital cataract. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.15647. Fulltekst i vitenarkiv
• Sand, Mari Kathrine; Cholidis, Symira; Kristianslund, Olav & Drolsum, Liv Kari (2022). Primary intraocular lens implantation in infants with unilateral congenital cataract operated before 12 weeks of age. Acta Ophthalmologica. ISSN 1755-375X. 100(5), s. 526–533. doi: 10.1111/aos.15155. Fulltekst i vitenarkiv Vis sammendrag

  Purpose The aim of this study was to report visual outcome and safety after cataract surgery with primary intraocular lens implantation before 12 weeks of age. Methods Infants with visually significant unilateral congenital cataract having primary IOL implantation in the capsular bag before 12 weeks of age in 2007–2016 were enrolled for a prospective study examination in 2017. The medical records were also reviewed. Results In total, 23 patients with a median age at cataract surgery of 32 days (range, 12–75 days) were included. Seventeen (74%) eyes had persistent foetal vasculature (PFV). After a median follow-up of 6.3 years (range, 1.4–10.9 years), the corrected distance visual acuity was 0.8 logMAR (range, 3.0–0.1 logMAR). All, except one eye, required surgery for visual axis opacification (VAO), with a median of two (range 0–5) additional surgical procedures. Four (17%) eyes developed secondary glaucoma. Conclusion Cataract surgery with primary IOL implantation before 12 weeks of age resulted in a high number of VAO operations, and the visual outcome varied considerably, showing the range in outcome for this challenging patient group. Co-existent PFV in these young patients was common. The incidence of secondary glaucoma was similar to other studies, despite the young age at surgery, high percentage of PFV and number of surgical procedures for VAO.

• Medin, Ingvild Helle; Dalby, Marius; Kure, Ingeborg Slørdahl Hjort; Karabeg, Mia; Drolsum, Liv Kari & Kristianslund, Olav (2022). Intraocular Inflammation in Eyes Operated for Late In-the-bag intraOcular lens dislocatioN (LION): A Randomized Clinical Trial. American Journal of Ophthalmology. ISSN 0002-9394. 238, s. 66–74. doi: 10.1016/j.ajo.2021.12.019. Fulltekst i vitenarkiv Vis sammendrag

  PURPOSE To compare the intraocular inflammation after 2 surgical approaches for late in-the-bag intraocular lens (IOL) dislocation. DESIGN Prospective, randomized, parallel-group clinical trial. METHODS We randomly assigned 100 patients (100 eyes) referred to Oslo University Hospital (tertiary referral center) with late in-the-bag IOL dislocation into IOL repositioning by scleral suturing (n=49) or IOL exchange with retropupillary fixation of an iris-claw lens (n=51). Patients were examined before surgery and 2 weeks, 6 weeks, and 6 months after surgery. The main outcome measure was anterior chamber laser flare, measured with a laser flare meter as photon counts per millisecond (pc/ms). RESULTS Two weeks following surgery, median flare values were 28.9 pc/ms (range, 7.9-140) in the repositioning group and 31.6 pc/ms (range, 9.8-92.3) in the exchange group (P = .83). Flare levels were still elevated after 6 weeks with no difference between the groups (P = .93), whereas it decreased to baseline levels after 6 months. Six weeks following surgery, the central retinal thickness was similar (P = .97); cystoid macular edema (CME) was found in 4 and 5 patients, respectively (P = .85); and the mean best corrected visual acuity was 0.17 (95% CI 0.09, 0.25) and 0.21 (95% CI 0.09, 0.32) logarithm of the minimum angle of resolution, respectively (P = .61). CONCLUSIONS This study revealed similar levels of intraocular inflammation following IOL repositioning and IOL exchange. There was no significant difference regarding risk of CME and visual outcome. The prolonged elevation in postoperative flare indicates a possible requirement for an extended anti-inflammatory treatment period after these operations.

• Medin, Ingvild Helle; Kure, Ingeborg Slørdahl Hjort; Dalby, Marius; Drolsum, Liv Kari & Kristianslund, Olav (2022). Long-term risk of suture breakage after scleral fixation of late in-the-bag intraocular lens dislocation with a polypropylene 10-0 suture. Journal of cataract and refractive surgery. ISSN 0886-3350. 48(12), s. 1408–1412. doi: 10.1097/j.jcrs.0000000000001010. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To investigate the long-term risk of suture breakage after scleral fixation with a polypropylene 10-0 suture in eyes with late in-the-bag intraocular lens (IOL) dislocation. Setting: Oslo University Hospital, Oslo, Norway. Design: Retrospective case series. Methods: Patients operated with scleral suturing of late in-the-bag IOL dislocation from 2007 to 2016. 192 eyes (176 patients) operated with scleral suture (polypropylene 10-0 suture) fixation of a dislocated IOL-capsule complex were identified; 91 patients (47%) were men. Results: The mean follow-up after the operation was 6.2 (95% CI, 5.7-6.7) years, and 98 patients (56%) deceased during the study. 11 eyes (6%) (11 patients) had suture breakage that required reoperation with a mean time of 5.5 (3.4-7.6) years after IOL repositioning surgery. These patients had a mean age of 73.5 (67.9-79.2) years at the time of the operation for late in-the-bag IOL dislocation vs 81.3 (79.8-82.9) years for patients who did not experience this complication (P = .004). No cases of late endophthalmitis were registered. Conclusions: The long-term risk of suture breakage was quite low after scleral fixation of late in-the-bag IOL dislocation, particularly in the oldest patients. Hence, the polypropylene 10-0 suture seems to be a safe option for scleral fixation in this patient group.

• Kristianslund, Olav; Hassaf, Safia Esmail & Drolsum, Liv Kari (2022). Optical Biometry and Lens Power Calculations in 500 Phakic Patients: Axial Length and Corneal Curvature in the Fellow Eye. Clinical Ophthalmology. ISSN 1177-5467. 16, s. 2775–2780. doi: 10.2147/OPTH.S375743. Fulltekst i vitenarkiv Vis sammendrag

  Objective: In eyes with severe corneal pathology, biometric measurements of the corneal curvature (K) can be challenging. The aims of this study were to test whether K mean values from the fellow eye can be used as substitute in lens power calculations and to determine if similarity in axial length (AL) in a patient’s two eyes implies similarity also in the corneal curvature. Methods and Analysis: A retrospective study of optical biometry measurements in 500 adults (1000 phakic eyes) that was scheduled for cataract surgery. Inclusion criteria were complete recordings of all parameters in both eyes and a signal-to-noise ratio of at least 10. Similar AL was defined as less than 0.3 mm difference between the patient’s two eyes. Results: The IOL power calculated with K mean from the fellow eye was 0.39 D (standard deviation (SD) 0.57) different from the calculation with both AL and K mean from the correct eye. The difference was larger than 1.0 D in 26 (5%) eyes. In patients with similar AL in their two eyes (n = 372), the interocular difference in K mean was 0.43 D (SD 0.67 D), compared to 0.45 D (SD 0.49 D) for the patients with an AL difference of 0.3 mm or more (n = 128) (p = 0.81). Conclusion: Lens calculations with keratometry values from the fellow eye as substitute yielded quite similar results as calculations with the correct values. Hence, this seems to be an acceptable approach in patients with incomplete keratometry recordings. Similarity in AL between a person’s two eyes did not imply more similar corneal curvatures.

• Sandvik, Gunhild Falleth; Rand-Hendriksen, Svend; Drolsum, Liv Kari & Kristianslund, Olav (2021). Pupillary response in adults with Marfan syndrome and its effect on straylight. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.15079. Fulltekst i vitenarkiv Vis sammendrag

  Purpose The main objective of this study was to examine the pupillary response in patients with Marfan syndrome (MFS) and secondarily to determine whether changes in the pupillary response are associated with the increased disability glare previously shown in the same patient population. Methods This study included 60 eyes of 34 patients with MFS diagnosed in accordance with the Ghent-2 criteria and 81 eyes of 44 controls. Pupillary response was measured with a pupillograph and disability glare with a straylight meter. Results The patients with MFS had a significantly smaller maximum pupil size than the control group, 4.87 (4.50–5.23) mm versus 5.58 (5.25–5.90) mm (p = 0.01). In addition, they exhibited slower contraction velocities (p = 0.03) and longer re-dilation times (p = 0.01) compared with the control group. The mean straylight value was higher in patients with MFS than controls, even when including pupillary parameters together with lens surgery, cataract, iris colour, axial length and corneal curvature as possible explanatory variables in the analysis. However, when including data from both groups, a significant negative correlation was seen between maximum pupillary diameter and straylight value (p = 0.01). The other pupillary parameters did not correlate with straylight. Conclusion Patients with MFS had a smaller maximum pupil diameter, slower pupillary contraction and longer re-dilation time than the controls. Despite the correlation between pupil size and straylight value, the pupillary response demonstrated in MFS eyes could not explain the increased straylight in these patients.

• Kristianslund, Olav & Drolsum, Liv Kari (2021). Prevalence of keratoconus in persons with down syndrome: A review. BMJ Open Ophthalmology. 6:e000754, s. 1–5. doi: 10.1136/bmjophth-2021-000754. Fulltekst i vitenarkiv Vis sammendrag

  Purpose Keratoconus is a vision-threatening condition, and there is a need for knowledge about the occurrence in subgroups of the population. The progression of the disease can be effectively stopped, and vision may be restored, if keratoconus is diagnosed at an early stage. The purpose of this review was to evaluate the literature of the prevalence of keratoconus in persons with Down syndrome. Methods We conducted a literature review of keratoconus prevalence in persons with Down syndrome. A thorough search was performed in Pubmed (Medline), and the quality of evidence was evaluated. Results The literature review identified 20 relevant studies, which reported keratoconus in 0%–71% of persons with Down syndrome. These studies varied greatly in design, patient selection, sample sizes and mean age, and the quality of evidence concerning estimates for the prevalence of keratoconus was generally evaluated as low. Most studies that included adults reported high prevalences of keratoconus–in many studies more than 10-fold the prevalence in the general population. No large screening studies in persons with Down syndrome were identified. Conclusions The present review showed that the prevalence of keratoconus in persons with Down syndrome is higher than in the general population. However, estimates from previous studies vary widely. Screening for keratoconus in this group should be considered.

• Kristianslund, Olav; Tovås, Linn Cesilie; Thorsrud, Andreas & Drolsum, Liv (2021). Keratokonus forekommer hyppigere enn antatt. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 141(5), s. 1–3. doi: 10.4045/tidsskr.20.1059. Fulltekst i vitenarkiv
• Kristianslund, Olav; Kure, Ingeborg Slørdahl Hjort & Drolsum, Liv (2021). Kataraktkirurgi i Norge 2010–19. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 141(9), s. 1–8. doi: 10.4045/tidsskr.20.1005. Fulltekst i vitenarkiv Vis sammendrag

  BAKGRUNN Kataraktkirurgi er et svært vanlig inngrep. Formålet med denne studien var å undersøke utviklingen i antall kataraktoperasjoner i Norge og karakteristika for pasienter som har gjennomgått kataraktkirurgi i perioden 2010–19. MATERIALE OG METODE Data om kataraktoperasjoner ble innhentet fra Norsk pasientregister. Antall kataraktoperasjoner per million innbyggere ble beregnet basert på befolkningsdata fra Statistisk sentralbyrå. RESULTATER Antall kataraktoperasjoner i Norge økte fra 36 340 i 2010 til 48 291 i 2019. Dette tilsvarte en økning på 21 % fra henholdsvis 7 480 til 9 063 per million innbyggere i samme periode. Gjennomsnittsalderen var 74 år, og over 90 % var over 60 år. Andelen kataraktopererte over 60 år var tilnærmet stabil i studieperioden. Kvinner utgjorde 60 % av de kataraktopererte i 2010 og 57 % i 2019. Andelen operasjoner utført av avtalespesialister samlet for perioden varierte fra 32 % i Helse Midt-Norge til 62 % i Helse Nord. FORTOLKNING Antallet kataraktoperasjoner økte gjennom perioden, tilsvarende befolkningsøkningen i aldersgruppen over 60 år. Med videre befolkningsvekst og stadig flere eldre må man trolig planlegge for en ytterligere økning av antall kataraktoperasjoner i årene som kommer.

• Sandvik, Gunhild Falleth; Rand-Hendriksen, Svend; Drolsum, Liv & Kristianslund, Olav (2021). Photophobia and disability glare in adult patients with Marfan syndrome: a case–control study. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.14935. Fulltekst i vitenarkiv Vis sammendrag

  Purpose The aim of the present study was to investigate photophobia and disability glare in adult patients with Marfan syndrome (MFS). Methods In this case–control study, 44 patients with MFS (87 eyes) were compared to 44 controls (88 eyes), who were matched for age and sex. The subjects were asked to grade their photophobia and glare using 10-cm visual analogue scales (VAS), which were marked with ‘never’ at zero and ‘always’ at 10 -cm. In addition, disability glare was measured with C-Quant straylight meter. Results The patients with MFS had significantly higher VAS scores than the controls in four out of seven statements related to photophobia and glare. When including cataract, spherical equivalent, iris colour, axial length and corneal curvature, three of the seven statements were still significantly different between the two groups. The mean straylight values were 1.29 ± 0.03 log(s) in the MFS group and 1.01 ± 0.03 log(s) in the control group (p < 0.001, mixed model). These differences remained significant after adjusting for cataract, spherical equivalent, iris colour, axial length and corneal curvature. Conclusion Patients with MFS reported more photophobia and had a higher straylight value than the control group. Awareness of these findings of more photophobia and glare in the MFS patients is important when counselling and treating these patients.

• Kristianslund, Olav; Sandvik, Gunhild Falleth & Drolsum, Liv Kari (2021). Long-Term Suture Breakage After Scleral Fixation of a Modified Capsular Tension Ring with Polypropylene 10-0 Suture. Clinical Ophthalmology. ISSN 1177-5467. 15, s. 2473–2479. doi: 10.2147/OPTH.S310648. Fulltekst i vitenarkiv Vis sammendrag

  Aim: To investigate the long-term risk of suture breakage after implantation of a modified capsular tension ring (MCTR) fixated to the sclera with polypropylene 10– 0 suture. Methods: Retrospective case series of operations for subluxated phakic lenses in 2007– 2015 with implantation of an MCTR secured with a 10– 0 polypropylene suture as part of an intraocular lens (IOL)-capsular bag complex. Results: We identified 132 eyes (92 patients) operated on with an MCTR. Of these eyes, 26 (20%) had suture breakage requiring re-operation, while another eight eyes (6%) had suture breakage that did not require surgery. The re-operations occurred after a mean 4.8± 3.3 years. Suture breakage occurred in patients with a mean age of 34.0± 23.3, as compared to 43.2± 26.0 years for patients who did not experience this complication (p=0.36). In patients aged 40 years or younger at the time of surgery, 47% experienced suture breakage in one or both eyes, as compared to 19% in the age group 41– 69 years and 13% in the age group 70 years and older (p=0.004). Of the 132 eyes that were operated on, we registered one case (0.8%) of possible suture-related late endophthalmitis. Conclusion: The long-term risk of suture breakage was quite high after scleral fixation of the MCTR in this patient cohort, and it seems as the risk is increased with young age.

• Sand, Mari Kathrine; Cholidis, Symira; Rimstad, Kjartan; Krekling, Elise Dees; Kristianslund, Olav & Drolsum, Liv Kari (2021). Long-term outcome of primary intraocular lens implantation in bilateral congenital cataract in infants with a median age of 35 days at surgery: A case series. BMJ Open Ophthalmology. 6:e000836, s. 1–7. doi: 10.1136/bmjophth-2021-000836. Fulltekst i vitenarkiv Vis sammendrag

  Objective To evaluate the long-term visual outcome and safety after bilateral cataract surgery with primary intraocular lens (IOL) implantation in infants with visually significant cataract at birth operated before 12 weeks of age. Methods and analysis Medical records of infants with congenital cataract who had bilateral surgery with primary IOL implantation before 12 weeks of age at Oslo University Hospital between 2007 and 2016 were retrospectively reviewed. Fifteen infants (30 eyes) were enrolled for a prospective study examination in 2017. Corrected distance visual acuity (CDVA) and intraocular pressure (IOP) were assessed. Visual axis opacification (VAO) was defined as opacification on the anterior or posterior surface of the IOL, capsular phimosis or fibrinous membrane. Secondary glaucoma was evaluated according to international guidelines. Results Median age at the time of primary surgery was 35 days (range, 15 to 70 days). There were no serious intraoperative complications, and all eyes had the IOL implanted in the capsular bag. After a median follow-up of 6.1 years (range, 1.5 to 10.2 years), the CDVA was 0.5 logMAR (range, 1.2 to 0.04). All eyes had surgery for VAO and the median number of surgical procedures was 2.0 (range, 1 to 5). The cumulative incidence of secondary glaucoma was 10% after 5 years of follow-up. Conclusion Primary IOL implantation before 12 weeks of age gave a satisfactory visual outcome, and the incidence of secondary glaucoma was similar to that reported after primary IOL implantation in older infants. However, the risk of VAO was high.

• Kristianslund, Olav & Drolsum, Liv Kari (2021). Prevalence of Keratoconus in Persons with down Syndrome in a National Registry in Norway. JAMA Network Open. 4(3), s. 1–3. doi: 10.1001/jamanetworkopen.2021.0814. Fulltekst i vitenarkiv Vis sammendrag

  Keratoconus is an eye condition with distinctive corneal characteristics, including thinning and a conical shape of the cornea. Keratoconus was previously considered rare; however, in recent studies, a prevalence of 0.2% to 0.3% has been reported1 and, in some studies, an even higher prevalence. An association of keratoconus with Down syndrome has been shown,2,3 although the exact reason remains unknown. In some studies, investigators have reported frequencies of keratoconus in persons with Down syndrome of 0% to 71%2-5; however, most have been limited by small sample sizes and biased patient selection. The aim of the present study was to estimate the prevalence of keratoconus among persons with Down syndrome in Norway.

• Drolsum, Liv & Kristianslund, Olav (2021). Implantation of retropupillary iris-claw lenses: A review on surgical management and outcomes. Acta Ophthalmologica. ISSN 1755-375X. 99(8), s. 826–836. doi: 10.1111/aos.14824. Fulltekst i vitenarkiv Vis sammendrag

  Iris-claw lenses have gained increasing popularity over the last years and are by many surgeons regarded as viable options in eyes with insufficient capsular or zonular support. The iris-claw lens has two haptics with fine fissures for folding (enclavating) the mid-peripheral part of the iris stroma and can either be placed in front of or posterior to the iris. In particular, the retropupillary implantation has been increasingly chosen probably due to having an anatomical position similar to that of the crystalline lens. The present review is based on a literature review and also on the authors’ clinical experience with this lens, and it focuses on surgical techniques and outcomes especially related to the characteristics of this lens, having haptics with claws that fixate the lens to the posterior iris. Implanting retropupillary iris-claw lenses has a relatively short learning curve, and there are only few complications reported during surgery. Retropupillary iris-claw lenses have demonstrated generally favourable efficiency and safety. However, the outcomes are probably more influenced by the reason for surgery and eye comorbidity than the lens itself. Albeit seldom reported, the postoperative complications have mostly been related to atrophy of the iris at the site of the haptics, or IOL decentration or disenclavation of one of the haptics. To date, however, there are few randomized clinical trials comparing this lens to other lens alternatives in eyes exhibiting insufficient capsular or zonular support for placing the lens in the ciliary sulcus. In the future, prospective studies with large samples should be performed to gain insights into the long-term safety of retropupillary placed iris-claw lenses, and for comparisons with the various other techniques of lens fixation.

• Kristianslund, Olav; Dalby, Marius & Drolsum, Liv Kari (2021). Late in-the-bag intraocular lens dislocation. Journal of cataract and refractive surgery. ISSN 0886-3350. 47(7), s. 942–954. doi: 10.1097/j.jcrs.0000000000000605. Fulltekst i vitenarkiv Vis sammendrag

  This review aimed to evaluate the cumulative incidence, patient characteristics, predisposing conditions, and treatment outcomes for late in-the-bag intraocular lens (IOL) dislocation. Literature searches in PubMed (MEDLINE), Embase, and Cochrane Library Central database identified 1 randomized clinical trial, 1 prospective case series, 2 prospective cohort studies, and 36 retrospective studies of this condition, which showed that the cumulative incidence was 0.5% to 3%, it occurred on average 6 to 12 years after cataract surgery, and mean patient age was 65 to 85 years. Pseudoexfoliation syndrome, myopia, and previous vitreoretinal surgery were the most common predisposing conditions. Studies indicated that IOL repositioning and IOL exchange provided similar visual outcomes and were equally safe. The long-term visual outcome seemed satisfactory. However, the quality of evidence regarding treatment was in general quite low. More studies of late in-the-bag IOL dislocation are needed, and in particular, different surgical techniques should be included in high-quality clinical trials.

• Dalby, Marius; Drolsum, Liv Kari & Kristianslund, Olav (2021). Repositioning surgery of different intraocular lens designs in eyes with late in-the-bag intraocular lens dislocation. Journal of cataract and refractive surgery. ISSN 0886-3350. 47(9), s. 1147–1152. doi: 10.1097/j.jcrs.0000000000000588. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To evaluate the long-term efficacy and safety after intraocular lens (IOL) repositioning by scleral suturing of 1-piece IOL compared with other IOL designs in the treatment of late in-the-bag IOL dislocation. Setting: Patients referred to Oslo University Hospital Oslo, Norway. Design: Prospective cohort study. Methods: The study comprised 54 patients (54 eyes) with late in-the-bag IOL dislocation treated with IOL repositioning by scleral sutures (10-0 polypropylene). All operations were performed with an anterior approach and by 1 surgeon. The following IOL designs were repositioned: 1-piece foldable (n = 17), 3-piece foldable (n = 28), plate-haptic (n = 8), and 1-piece rigid (n = 1) IOLs. Patients were evaluated comprehensively preoperatively and at 6 months (80%), 1 year (67%), and 2 years (61%) postoperatively. The main outcome measures were efficacy regarding corrected distance visual acuity (CDVA) and spherical equivalent (SE) and safety regarding complications. Results: Postoperative visual acuity was similar for different IOL designs. The mean SE change to final observation was −0.08 (95% CI, −0.93 to 0.77) in the 1-piece IOL group (n = 11) and −0.98 (−1.73 to −0.23) in the 3-piece IOL group (n = 18) (P = .11). Regarding safety, no patients had uveitis–glaucoma–hyphema syndrome, retinal detachment, or endophthalmitis. The 3-piece IOL group had 1 case of redislocation and 1 case of iritis. No patients had symptoms related to clinical IOL decentration. Long-term intraocular pressure remained within normal limits with overlapping 95% CIs for different IOLs. Conclusions: Repositioning surgery of 1-piece IOLs seems as efficient and safe as that for other IOL designs in the treatment of late in-the-bag IOL dislocation.

• Kristianslund, Olav; Hagem, Anne Marie; Thorsrud, Andreas & Drolsum, Liv (2020). Prevalence and incidence of keratoconus in Norway: a nationwide register study. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.14668. Fulltekst i vitenarkiv Vis sammendrag

  Purpose To estimate the national prevalence and incidence of keratoconus in Norway. Methods In this epidemiologic study, data were obtained from the Norwegian Patient Registry, which provides information from all publicly funded specialist care in Norway. Prevalence of keratoconus was estimated from the total number of patients registered with this diagnosis and incidence from the annual frequency of first‐time registrations of patients up to 40 years of age in the period 2010–2018. Data on age and gender of the keratoconus patients were also gathered. Results A total of 9832 keratoconus patients were registered. The estimated prevalence in the general population was 192.1 per 100 000 (95% confidence interval (CI): 188.3–195.9), and the estimated annual incidence was 19.8 per 100 000 (95% CI: 18.1–21.5). There was a predominance of males (73%), and mean age for all patients was 37.5 years at first registration in this period. Conclusion This study reports the frequency of keratoconus from a national patient register during a time period with available modern diagnostic tools. The estimated prevalence and incidence were higher than most previous estimates and show that keratoconus is not a rare condition. As screening was not part of the study, the true prevalence in the general population may be even higher.

• Kristianslund, Olav; Dalby, Marius & Drolsum, Liv (2020). Dislokasjon av kunstig linse. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 7. doi: 10.4045/tidsskr.19.0526. Fulltekst i vitenarkiv
• Dalby, Marius; Kristianslund, Olav; Østern, Atle Einar; Falk, Ragnhild Sørum & Drolsum, Liv (2020). Longitudinal corneal endothelial cell loss after corrective surgery for late in-the-bag IOL dislocation: a randomized clinical trial. Journal of cataract and refractive surgery. ISSN 0886-3350. 46(7), s. 1030–1036. doi: 10.1097/j.jcrs.0000000000000213. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To compare safety regarding longitudinal corneal endothelial cell loss (ECL) after IOL exchange vs IOL repositioning for late in-the-bag IOL dislocation. Setting: Oslo University Hospital, Norway. Design: Prospective, parallel group, randomized clinical trial. Methods: During a 3-year period, 104 patients were randomly assigned to groups receiving either IOL exchange with retropupillary fixation of an iris-claw IOL (n = 50) or IOL repositioning by scleral suturing (n = 54). All operations were performed by 1 surgeon with an anterior approach. Endothelial cell density (ECD) and central corneal thickness were measured preoperatively and at 6 months, 1 year, and 2 years postoperatively. A linear mixed model was applied for the longitudinal analysis, where patients with at least 1 ECD measurement were included (n = 44 exchange; n = 50 repositioning). The main outcome measure was 2-year longitudinal ECL in IOL exchange compared with IOL repositioning. Results: The longitudinal ECL was similar between the IOL exchange (n = 44) and IOL repositioning (n = 50) groups during the 2 years of follow-up (17.5% vs 15.3%, P = .15). A subgroup analysis found no reason to advise against either method for patients with low preoperative ECD (<1500 cells/mm2). The mean central corneal thickness was similar between the 2 groups and remained stable over 2 years of follow-up. Conclusions: This randomized clinical trial of late in-the-bag IOL dislocation surgery found that exchanging the IOL was as safe as repositioning in terms of 2-year longitudinal ECL.

• Bisevac, Jovana; Anisimova, Natalia S.; Nagymihaly, Richard; Kristianslund, Olav; Katta, Kirankumar & Noer, Agate [Vis alle 11 forfattere av denne artikkelen] (2020). Long-term myofibroblast persistence in the capsular bag contributes to the late spontaneous in-the-bag intraocular lens dislocation. Scientific Reports. 10, s. 1–17. doi: 10.1038/s41598-020-77207-7. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Late spontaneous in-the-bag intraocular lens (IOL) dislocation is a complication presenting 6 months or later after cataract surgery. We aimed to characterize the cells in the lens capsules (LCs) of 18 patients with spontaneous late in-the-bag IOL dislocation. Patients' average age was 82.6 ± 1.5 years (range 72–98), and most of them had pseudoexfoliation syndrome (PEX). Cells from the LCs were positive for myofibroblast (αSMA), proliferation (Ki-67, PCNA), early lens development/lens progenitor (SOX2, PAX6), chemokine receptor (CXCR4), and transmembrane (N-cadherin) markers, while negative for epithelial (E-cadherin) marker. Moreover, the cells produced abundant fibronectin, type I and type V collagen in the nearby extracellular matrix (ECM). During ex vivo cultivation of dislocated IOL-LCs in toto, the cells proliferated and likely migrated onto the IOL’s anterior side. EdU proliferation assay confirmed the proliferation potential of the myofibroblasts (MFBs) in dislocated IOL-LCs. Primary cultured lens epithelial cells/MFBs isolated from the LC of dislocated IOLs could induce collagen matrix contraction and continuously proliferated, migrated, and induced ECM remodeling. Taken together, this indicates that long-lived MFBs of dislocated IOLs might contribute to the pathogenic mechanisms in late in-the-bag IOL dislocation.

• Kristianslund, Olav; Pathak, Meeta; Østern, Atle Einar & Drolsum, Liv (2019). Corneal endothelial cell loss following cataract surgery in patients with pseudoexfoliation syndrome: a 2‐year prospective comparative study. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.14314. Fulltekst i vitenarkiv
• Dalby, Marius; Kristianslund, Olav & Drolsum, Liv (2019). Long-Term Outcomes after Surgery for Late In-The-Bag Intraocular Lens Dislocation: A Randomized Clinical Trial. American Journal of Ophthalmology. ISSN 0002-9394. 207, s. 184–194. doi: 10.1016/j.ajo.2019.05.030. Fulltekst i vitenarkiv Vis sammendrag

  Purpose To compare the long-term efficacy and safety of 2 operation methods for late in-the-bag intraocular lens (IOL) dislocation. Design Prospective, randomized, parallel group surgical clinical trial. Methods During a 3-year period, 104 patients (104 eyes) were assigned one group for IOL repositioning by scleral suturing (n = 54) or one group for IOL exchange by retropupillary fixation of an iris claw IOL (n = 50). A single surgeon performed all operations using an anterior approach. Patients were examined before surgery and at 6 months and 1 and 2 years after surgery. The present study included the 66 patients (63%) who completed the 2-year follow-up, and the main outcaome measurement was corrected distance visual acuity (CDVA) 2 years after surgery. Results After 2 years, the mean CDVA was 0.20 ± 0.29 logarithm of the minimum angle of resolution (logMAR) units (range, −0.18 to 1.10) in the repositioning group and 0.22 ± 0.30 logMAR (range, −0.10 to 1.22) in the exchange group (P = .69). A CDVA of 20/40 or better was achieved by 76% of all patients. Four eyes (12%) had cystoid macular edema in the repositioning group compared with 5 eyes (15%) in the exchange group. Two eyes underwent redislocation (1 in each group). There were no cases of endophthalmitis or retinal detachment. Conclusions There were no significant differences between the visual acuity using IOL repositioning and that using IOL exchange 2 years after surgery. The two methods were equally efficient and safe from a long-term perspective and are both considered acceptable treatments.

• Kristianslund, Olav; Dalby, Marius; Moe, Morten Carsten & Drolsum, Liv (2019). Cost-effectiveness analysis in a randomized trial of late in-the-bag intraocular lens dislocation surgery: repositioning versus exchange. Acta Ophthalmologica. ISSN 1755-375X. 97(8), s. 1–7. doi: 10.1111/aos.14108. Fulltekst i vitenarkiv Vis sammendrag

  Purpose To compare the cost‐effectiveness of two operation methods for late in‐the‐bag intraocular lens (IOL ) dislocation. Methods In this randomized clinical trial, 104 patients were randomly assigned to IOL repositioning by scleral suturing (n = 54) or IOL exchange with a retropupillary iris‐claw lens (n = 50). A cost‐effectiveness analysis (CEA ) was performed in conjunction with previously published 6‐month efficacy and safety results. An incremental cost‐effectiveness ratio was calculated as the cost difference between the operation groups relative to their difference in postoperative corrected distance visual acuity (CDVA ) (mean and 95% confidence interval: minimum and maximum), reported as the cost difference in United States Dollars ($) per logMAR difference. Results Exchange surgery was $281.20 ± 17.66 more expensive than repositioning, mainly explained by the new IOL and the frequent use of anterior vitrectomy. A previous trial publication revealed no significant difference in the 6‐month postoperative CDVA between the groups. In the CEA , the mean group difference yielded an incremental cost‐effectiveness ratio of −$281.20 per −0.11 logMAR (‐$1108/QALY ) in favour of repositioning, ranging from −$281.20 per −0.29 logMAR (‐$406/QALY ) in favour of repositioning to +$281.20 per −0.08 logMAR (+$1522/QALY ) in favour of exchange. The CEA did not include the mean 9.5 min shorter operation time for exchange. Conclusion Repositioning tended to be more cost‐effective than exchange; however, this is modified if also considering the operation time. Overall, it seems the cost‐effectiveness is not alone sufficiently different to recommend one of the operation methods over the other for late in‐the‐bag IOL dislocation.

• Kristianslund, Olav; Dalby, Marius & Drolsum, Liv (2019). High intraocular pressure in eyes with late in-the-bag intraocular lens dislocation. Journal of cataract and refractive surgery. ISSN 0886-3350. 45(7), s. 1043–1044. doi: 10.1016/j.jcrs.2019.02.042. Fulltekst i vitenarkiv Vis sammendrag

  The frequency of late in-the-bag intraocular lens (IOL) dislocation has increased over the past decades. Important predisposing factors are pseudoexfoliation syndrome (PXF), myopia, previous vitreoretinal surgery, and trauma,1–3 and there is also an association with glaucoma.1–4 Furthermore, some studies report high intraocular pressure (IOP) in eyes with IOL dislocation despite no known glaucoma.1–5 Accordingly, it has been speculated whether the dislocation can cause an IOP increase. In a recent study addressing the association between high IOP and spontaneous in-the-bag IOL dislocation, Lorente Bulnes et al.6 found a significant trend toward higher IOP when a lower grade of dislocation was diagnosed. They suggested that movement of the loosened IOL in mild dislocation might cause iris chafing. The aim of the present analysis was to evaluate the possible association between the IOP at diagnosis and the grade of IOL dislocation in a large clinical trial.

• Råen, Marianne; Kristianslund, Olav; Østern, Atle Einar; Sandvik, Gunhild Falleth & Drolsum, Liv (2019). Are Elderly Patients Optimally Corrected with Spectacles in the Longer Term after Cataract Surgery? Optometry and Vision Science. ISSN 1040-5488. 96(5), s. 362–366. doi: 10.1097/OPX.0000000000001371. Fulltekst i vitenarkiv
• Kristianslund, Olav; Råen, Marianne; Østern, Atle Einar & Drolsum, Liv (2017). Late In-the-Bag Intraocular Lens Dislocation: A Randomized Trial Comparing Lens Repositioning and Lens Exchange. Ophthalmology (Rochester, Minn.). ISSN 0161-6420. 124(2), s. 151–159. doi: 10.1016/j.ophtha.2016.10.024. Fulltekst i vitenarkiv Vis sammendrag

  Purpose To compare the efficacy and safety of 2 operation methods for late in-the-bag intraocular lens (IOL) dislocation. Design Prospective, randomized, parallel-group surgical trial. Participants Patients referred to Oslo University Hospital (tertiary referral center). Methods We randomly assigned 104 patients (104 eyes) either to IOL repositioning by scleral suturing (n = 54) or to IOL exchange with retropupillary fixation of an iris-claw IOL (n = 50). One surgeon performed all operations. Patients were evaluated comprehensively before surgery, and most patients (82%) attended an examination 6 months after surgery. Main Outcome Measures Best-corrected visual acuity (BCVA) 6 months after surgery. Results The mean postoperative BCVA was 0.24±0.29 logarithm of the minimum angle of resolution (logMAR) units (range, −0.18 to 1.16 logMAR) in the repositioning group and 0.35±0.54 logMAR (range, −0.20 to 3.0 logMAR) in the exchange group (P = 0.23). A BCVA of 20/40 or better (Snellen) was reached by 61% and 62% of the patients, respectively (P = 0.99). The mean postoperative corneal cylinder was 1.2±1.0 and 1.2±0.8 diopters, respectively (P = 0.84), and the postoperative endothelial cell density changes were −3±10% (P = 0.07) and −10±14% (P = 0.001), respectively (group difference, P = 0.04). Repositioning had a longer mean surgical time than exchange (P < 0.001). There were 2 (4%) and 0 cases of perioperative fluid misdirection syndrome, respectively. Postoperative complications were intraocular pressure (IOP) increase (n = 12), cystoid macular edema (CME; n = 3), and nonarteritic anterior ischemic optic neuropathy (n = 1) in the repositioning group, and IOP increase (n = 9), pupillary block (n = 1), choroidal effusion (n = 2), CME (n = 4), and redislocation (n = 1) in the exchange group. Conclusions We found satisfactory and not significantly different outcomes for BCVA 6 months after surgery in the 2 groups. Both operation methods seemed safe, with low frequencies of serious perioperative and postoperative complications. However, some of the observed differences in complications should be taken into consideration when selecting the most suitable method in clinical practice.

• Kristianslund, Olav; Råen, Marianne; Østern, Atle Einar & Drolsum, Liv (2017). Glaucoma and Intraocular Pressure in Patients Operated for Late In-the-bag Intraocular Lens Dislocation: A Randomized Clinical Trial. American Journal of Ophthalmology. ISSN 0002-9394. 176, s. 219–227. doi: 10.1016/j.ajo.2017.01.026. Fulltekst i vitenarkiv
• Kristianslund, Olav; Østern, Atle Einar & Drolsum, Liv (2017). Astigmatism and Refractive Outcome After Late In-The-Bag Intraocular Lens Dislocation Surgery: A Randomized Clinical Trial. Investigative Ophthalmology and Visual Science. ISSN 0146-0404. 58(11), s. 4747–4753. doi: 10.1167/iovs.17-22723. Fulltekst i vitenarkiv Vis sammendrag

  Purpose: To compare surgically induced astigmatism (SIA) and refractive outcomes between two operation methods for late in-the-bag IOL dislocation. Methods: In this prospective, randomized, parallel-group clinical trial, 104 patients (eyes) were assigned to IOL repositioning by scleral suturing 1.5- to 2-mm posterior to limbus (n = 54) or IOL exchange with a retropupillar iris-claw IOL using a 5.5-mm scleral pocket incision (n = 50). The SIA was determined by vector analysis through conversion of corneal cylinders to Cartesian coordinates, and is presented as magnitude in diopters @ direction in degrees (D @ °). Follow-up was 6 months. Results: The SIA was 0.24 D @ 8° for IOL repositioning and 0.65 D @ 171° for IOL exchange, which was a nonsignificant group difference (X coordinate: P = 0.08; Y coordinate: P = 0.16). Mean SIA magnitude was 0.60 ± 0.50 D and 1.12 ± 0.85 D, respectively (P < 0.001). Mean postoperative spherical equivalent was −1.6 ± 1.6 D after IOL repositioning and −0.5 ± 1.0 D after IOL exchange (P < 0.001). For IOL repositioning, this represented a mean myopic shift of −0.7 ± 1.1 D compared with before the IOL dislocation (P < 0.001). For IOL exchange, it was within ±1 D of target refraction in 83% of the patients. Conclusions: Surgically induced astigmatism was modest in both operation groups, albeit with a tendency of being more pronounced for IOL exchange. Repositioning surgery led to a myopic shift, whereas exchange surgery provided good refractive predictability.

• Kristianslund, Olav; Østern, Atle Einar; Råen, Marianne; Sandvik, Gunhild & Drolsum, Liv (2016). Does cataract surgery reduce the long-term risk of glaucoma in eyes with pseudoexfoliation syndrome? Acta Ophthalmologica. ISSN 1755-375X. 94(3), s. 261–265. doi: 10.1111/aos.12945. Fulltekst i vitenarkiv

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• Noor, L.; Bjerkreim, Hilde; Five, Christian K.; Haugaa, Kristina Ingrid Helena Hermann; Drolsum, Liv Kari & Kristianslund, Olav (2024). Prevalence of keratoconus in persons with mitral valve prolapse in a nationwide register study. Acta Ophthalmologica. ISSN 1755-375X. doi: 10.1111/aos.16786. Fulltekst i vitenarkiv
• Kristianslund, Olav; Bøhler, Anders Djupesland; HAGEM, ANNE MARIE; Tveit, Jon Henrik & Tønseth, Turid Skei (2022). Ny og bedre behandling for glaukom? Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 142. doi: 10.4045/tidsskr.22.0058. Fulltekst i vitenarkiv
• Kristianslund, Olav & Drolsum, Liv (2017). Late in-the-bag intraocular lens dislocation: a randomised trial comparing refractive outcomes and astigmatism after lens repositioning vs lens exchange. Fulltekst i vitenarkiv
• Kristianslund, Olav & Drolsum, Liv (2017). Late in-the-bag intraocular lens dislocation, high intraocular pressure and glaucoma: a randomised clinical trial comparing lens repositioning and lens exchange. Fulltekst i vitenarkiv
• Kristianslund, Olav & Drolsum, Liv (2016). Sen dislokasjon av IOL/kapsel-apparatet: en randomisert klinisk studie med sammenlikning av to operasjonsmetoder. Fulltekst i vitenarkiv
• Kristianslund, Olav & Drolsum, Liv (2016). A randomised controlled trial comparing two operation methods for late in-the-bag intraocular lens dislocation. Fulltekst i vitenarkiv

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