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SEVİK, MEHMET ORKUN

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MEHMET ORKUN

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    Resolution of cystoid macular edema with topical carbonic anhydrase inhibitor in a patient with retinal dystrophy associated with Cohen syndrome
    (TAYLOR & FRANCIS INC, 2021) SEVİK, MEHMET ORKUN; Sevik, Mehmet Orkun; Aykut, Aslan; Sahin, Ozlem
    Background: Cohen Syndrome (CS) is an autosomal recessive multisystemic disorder characterized by various ophthalmologic findings, including retinal dystrophy and associated cystoid macular edema (CME), in which there was no known effective treatment approach. Material and Methods: We describe a CS patient with a homozygous c.62 T > G, p.(Leu21*) mutation in the VPS13B gene with a topical carbonic anhydrase inhibitor (CAI; brinzolamide %1, thrice daily) responding CME. Case Description: A seven-year-old girl with an established diagnosis of CS was referred with a primary complaint of nyctalopia. On ophthalmologic examination, bilateral decreased visual acuity and normal-appearing macula with mild optic disc pallor were present. However, the detailed evaluation revealed bilateral blunted foveal reflexes, barely visible foveal pigmentation, and slightly attenuated retinal vessels without any peripheral retinal pigmentary changes in dilated fundus examination, and CME on optical coherence tomography. Bilateral topical brinzolamide thrice daily was initiated for CME. Visual acuity increased, and CME was resolved except for minimal schisis at the inner nuclear layer level at the third-month follow-up visit and remained stable up to one-year follow-up. CME reappeared after five months of self-discontinuation of the patient's therapy but resolved again with treatment resumption. Conclusion: We report the first case of CME secondary to rod-cone dystrophy associated with CS showing improvement in anatomy and visual acuity with a topical CAI.
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    PublicationOpen Access
    Predictive factors of complications and visual outcomes after pediatric cataract surgery: A single referral center study from Türkiye
    (2023-10-01) DERİCİOĞLU, VOLKAN; SEVİK, MEHMET ORKUN; BAĞATUR VURGUN, ELİF; ÇERMAN, EREN; DERİCİOĞLU V., SEVİK M. O., BAĞATUR VURGUN E., ÇERMAN E.
    Objectives: To evaluate the predictive factors of complications and visual acuity outcomes in pediatric cataract patients. Materials and Methods: This retrospective, observational clinical study included 80 eyes of 50 patients treated for pediatric cataracts between 2010 and 2020. The eyes were divided into Group I (congenital cataracts, n=38) and Group II (developmental cataracts, n=42). Group II was also divided into Group IIA (aphakic, n=21) and Group IIB (pseudophakic, n=21). The effects of the age, laterality, cataract morphology, intraocular lens implantation, preoperative nystagmus/strabismus, and intraoperative anterior hyaloid rupture on complications and final best-corrected visual acuity (BCVA; logMAR) were evaluated. Results: The median (interquartile range) age and follow-up time were 28 (5-79) months and 60 (29-84) months, respectively. There was a significant difference in mean final BCVA between Group I (0.79±0.46) and Group II (0.57±0.51) (p=0.047); however, no difference was observed between Group IIA and Group IIB (p=0.541). Having congenital cataract (p=0.045), preoperative nystagmus/strabismus (p=0.042), total/ mature cataract (p<0.001), and postoperative complications (p=0.07) were significantly associated with final BCVA. However, in multivariate analysis, only total/mature cataract (β: 0.52, p<0.001) and having any complication (β: 0.24, p=0.018) were associated with final BCVA. Congenital cataract and intraoperative anterior hyaloid rupture were the only significant risk factors of postoperative complications on univariate (p=0.027 and p=0.003, respectively) and binary logistic regression analysis (odds ratio [OR]: 2.95 [95% confidence interval: 1.07-8.15], p=0.036 and OR: 4.28 [95% confidence interval: 1.55-11.77], p=0.005, respectively). Conclusion: Total/mature cataract and the presence of any postoperative complication adversely affected the final BCVA. Having a congenital cataract and intraoperative anterior hyaloid membrane rupture increased the risk of complications.
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    PublicationOpen Access
    Juvenile Xanthogranuloma Presented with Buphthalmos and Corneal Clouding in Neonatal Period: A Case Report
    (2022-05-01) DERİCİOĞLU, VOLKAN; SEVİK, MEHMET ORKUN; ERASLAN, MUHSİN; DERİCİOĞLU V., SEVİK M. O. , ERASLAN M., Dirican B., Yücelten D., Cinel L.
    Aim: To report an ocular juvenile xanthogranuloma (JXG) case presented with buphthalmos, corneal cloudiness, and normal intraocular pressure (IOP) in the neonatal period and treated with Ahmed glaucoma valve (AGV) implantation. Background: JXG is a rare disorder predominantly seen in infants, but the neonatal presentation is extraordinary. Although spontaneous hyphema is a common presenting sign in JXG, buphthalmos and corneal opacity in the neonatal period were reported only in one case, which had high IOP values at presentation. Case presentation: Sixteen-day-old male patient presented with buphthalmos, diffuse corneal clouding, and 11 mm Hg of IOP value in the right eye. IOP increased to 28 mm Hg three weeks later, and spontaneous hyphema developed, which did not respond to antiglaucomatous medications and topical corticosteroids. AGV was implanted, and the IOP decreased to 13 mm Hg postoperatively. In the follow-ups, numerous firm yellowish nodules were noticed on the patient’s skin during the examination under general anesthesia. Histopathological examination of the skin nodules was compatible with the diagnosis of JXG. Lens subluxation and phacodonesis were developed during the follow-up and were managed with pars plana lensectomy. After a silent period of 3 months, epithelial ingrowth was determined around the side port entrance. Unfortunately, the ingrowth did not respond to cryotherapy and resulted in phthisis bulbi. Pathological evaluation of the enucleated phthisic eye revealed posterior segment involvement. Conclusion: Ocular JXG can be present with buphthalmos, corneal opacity, and normal IOP values without any skin lesions in the neonatal period. Neonatal presentation of JXG may be associated with limited medical therapy response and aggressive disease course. Clinical significance: This case report introduces the second ocular JXG case, which presented with buphthalmos and corneal cloudiness, and the third pathologically proven posterior segment involvement of JXG in the literature.
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    Pediatrik optik gliom olgularının görme keskinlikleri ile elektofizyolojik ve radyolojik bulgularının değerlendirilmesi
    (2022-04-23) DERİCİOĞLU, VOLKAN; EKER, NURŞAH; BUĞDAYCI, ONUR; YARGI, BERRU; KURŞUN, MELTEM; SEVİK, MEHMET ORKUN; TOKUÇ, AYŞE GÜLNUR; ŞAHİN, ÖZLEM; Dericioğlu V., Eker N., Buğdayci O., Yargi B., Kurşun M., Sevik M. O. , Tokuç A. G. , Şahin Ö.
    Amaç:Optik gliom nedeniyle takip edilen pediatrik hastaların en iyi düzeltilmiş görme keskinliği (EİDGK, logMAR), flaş görsel uyarılmış potansiyeller (fVEP) ve manyetik rezonans görüntüleme (MRG) sonuçlarının karşılaştırılması.Yöntem:Marmara Üniversitesi Göz Hastalıkları, Pediatrik Onkoloji ve Radyoloji bölümlerince takip edilen 22 pediatrik optik gliom hastasının 38 gözü çalışmaya dahil edildi. Hastaların başlangıç ve son takipteki EİDGK’leri, MRG’deki optik sinir kalınlıkları (OSK), kontrast tutulumları, sinyal değişimleri ve fVEP’te P2 dalgasının amplitüd ve latansları değerlendirildi.Bulgular:Hastaların yaş ortalamaları 12±5.7 yıl ve kız/erkek oranı 13/9 idi. Ortalama takip süresi 63.95±24.5 ay olarak bulundu. Gözlerin ilk ve son EİDGK’leri sırasıyla, ortanca (1.ve 3. çeyrekler aralığı) 0.2 (0-2.18) ve 0.2 (0-2.3) logMAR (p=0.586); MRG’de ölçülen ortalama OSK’leri sırasıyla, 6.51±6.03 ve 6.31±7.84 mm (p=0.650); fVEP P2 dalga ortalama amplitüdleri sırasıyla, 16.68±14.21 ve 17.93±11.96 mV (p=0.577) ve ortalama latansları sırasıyla, 149.38±50.30 ve 133.39±29.78 ms (p=0.009) olarak saptandı. Son logMAR EİDGK ile OSK (r=0.434, p=0.015), P2 amplitüdü (r=-0.432, p=0.014)) ve P2 latansı (r=0.614, p<0.001) arasında anlamlı orta düzeyde korelasyon olduğu görüldü. fVEP P2 dalga parametreleri ile OSK arasında korelasyon saptanmadı (p>0.05). P2 latansı ile MRG’de görülen sinyal (r=0.426, p=0.013) ve kontrast tutulumu (r=0.386, p=0.027) değişiklikleri arasında anlamlı korelasyon olduğu görüldü.Sonuç:Optik gliom hastalarında fVEP P2 dalga amplitüdleri ve latansları EİDGK ile ilişkili gözükmektedir. Ayrıca, P2 dalga latansının MRG’de görülen sinyal ve kontast tutulumu değişiklikleri ile de ilişkili olduğu görülmektedir. Bu bulgular, özellikle preverbal yaştaki optik gliom hastalarının değerlendirilmesinde ve hastalık ilerlemesinin takibinde fVEP’in kulanılabileceğini göstermektedir.
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    PublicationOpen Access
    The effect of COVID-19 pandemic restrictions on neovascular AMD patients treated with treat-and-extend protocol
    (SPRINGER, 2021-09) ÖZKAN, GAMZE; Sevik, Mehmet Orkun; Aykut, Aslan; Ozkan, Gamze; Dericioglu, Volkan; Sahin, Ozlem
    Purpose To investigate the adherence rate of neovascular age-related macular degeneration (nAMD) patients in treat-and-extend (TAE) protocol to their anti-vascular endothelial growth factor (anti-VEGF) intravitreal injection (IVI) appointments and to evaluate the functional and anatomical outcomes of the patients who attended and did not attend their IVI appointments during the coronavirus disease 2019 (COVID-19) restriction period (RP). Methods The patients with nAMD having IVI appointments between March 16 and June 1, 2020 (RP in Turkey) were included in this retrospective study. For adherence analysis, the patients who attended (Group 1, n = 44) and who did not attend (Group 2, n = 60) their IVI appointment visits during the RP (V-RP) were evaluated according to their last visit before the RP (V-0). For outcome analysis, the patients who attend V-RP and have follow-up (Group 1a, 46 eyes) and who did not attend V-RP but later attended for follow-up (Group 2a, 33 eyes) were evaluated for functional (best-corrected visual acuity, BCVA [logMAR]) and anatomical (optical coherence tomography [OCT] disease activity) outcomes at the first visit after RP (V-1) and last visit within six months after RP (V-2). Patients received a complete ophthalmologic evaluation with anti-VEGF (Aflibercept) IVI administration at all visits. Results The adherence rate of the patients to V-RP was 42.3% (44/104). The patients in Group 1 were significantly younger (mean +/- SD years, 71.0 +/- 8.1 vs. 74.7 +/- 8.0, p = 0.024), had better median [IQR] BCVA at their first presentation (0.30 [0.54] vs. 0.61 [1.08], p = 0.023) and V-0 (0.40 [0.48] vs. 0.52 [0.70], p = 0.031), and had less hypertension (36.4% vs. 58.3%, p = 0.044) than Group 2. The mean +/- SD delay of planned IVI at V-RP in Group 2a was 13.9 +/- 6.2 weeks. Disease activity in OCT was significantly higher in Group 2a than Group 1a at V-1 (60.6% vs. 32.6%, p = 0.025). In Group 2a, the median (IQR) BCVA was significantly worse at V-1 (0.70 [0.58]) and V-2 (0.70 [0.59]) than V-0 (0.52 [0.40], p = 0.047 and p = 0.035, respectively). Conclusions More than half of the scheduled nAMD patients in TAE protocol missed their IVI visits during the RP, which resulted in a delay of their treatments. The delay of IVI treatment in those patients resulted in an increase in OCT disease activity and a decrease in BCVA.
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    Retina hastalıklarında elektrodiagnostik testlerin kullanımı
    (Anadolu Yayınları, 2022-01-01) SEVİK, MEHMET ORKUN; ŞAHİN, ÖZLEM; Sevik M. O., Şahin Ö.
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    PublicationOpen Access
    A useful method for the practice of pneumatic retinopexy: Slit-lamp laser photocoagulation through the gas bubble
    (2023-05-01) SEVİK, MEHMET ORKUN; KUBAT, BETÜL; DERİCİOĞLU, VOLKAN; ŞAHİN, ÖZLEM; Aykut A., SEVİK M. O., KUBAT B., DERİCİOĞLU V., ŞAHİN Ö.
    This study aimed to demonstrate the laser retinopexy method through the gas bubble under a slit-lamp biomicroscope using a wide-field contact lens to treat rhegmatogenous retinal detachment (RRD) with pneumatic retinopexy (PR) and report its anatomical and functional results. This single-center, retrospective case series included RRD patients treated with PR using sulfur hexafluoride (SF6). The demographics, preoperative factors, and anatomical and functional outcomes were collected from the patient files. The single-procedure success rate of PR at postoperative 6th months was 70.8% (17/24 eyes), and the final success rate after secondary surgeries was 100%. The BCVA was better in the successful PR eyes at postoperative 3rd (p = 0.011) and 6th month (p = 0.016) than in failed eyes. No single preoperative factor was associated with PR success. The single-procedure success rate of PR using the laser retinopexy method through the gas bubble with a wide-field contact lens system seems comparable to the PR literature.
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    Topical Treatment of Persistent Epithelial Defects with a Matrix Regenerating Agent
    (MARY ANN LIEBERT, INC, 2018) TOKER, AYŞE EBRU; Sevik, Mehmet Orkun; Turhan, Semra Akkaya; Toker, Ebru
    Purpose: The aim of the study was to assess the efficacy of a topical regenerating agent (RGTA) for management of persistent epithelial defects (PEDs) resistant to conventional therapy. Methods: Twenty-one patients (23 eyes) with PEDs despite the use of conventional therapy for lagophthalmos (n = 4), neurotrophic ulcer (n = 9), chemical burn (n = 3), Stevens-Johnson syndrome (n = 1), atopic keratoconjunctivitis (n = 1), severe dry eye (n = 2), peripheral ulcerative keratitis (n = 1), fungal keratitis (n = 1), and bacterial keratitis (n = 1) were enrolled in the study. Patients were treated with RGTA (Cacicol; Thea, Paris, France) instilled at a dosage of one drop on alternate days. Patients were evaluated by slit-lamp examination, anterior segment photography, and fluorescein-dye testing. Ulcer areas were noted on alternate days starting from the first day of instillation. Results: Twenty of 23 eyes (86.9%) displayed complete corneal healing after a mean period of similar to 7.2 days (range, 2-20 days). Mean decrease ratio of ulcer area observed was 61.2% (range, 8.8%-100%, n = 19) on the 2nd day, 74.4% (range, 36%-100%, n = 16) on the 4th day, 80.2% (range, 43.7%-100%, n = 12) on the 6th day, 88.5% (range, 55.9%-100%, n = 9) on the 8th day, and 85.5% (range, 58.3%-100%, n = 7) on the 10th day. No significant differences were found in the epithelialization speed between eyes with and without bandage contact lenses in any postoperative day (P > 0.05). There were no treatment-related local or systemic side effects during the study. Conclusions: RGTA seems to be an effective therapeutic alternative in the treatment of persistent corneal epithelial defects.
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    PublicationOpen Access
    Choroidal vascularity index as an activity criterion and a treatment response measure in chronic central serous chorioretinopathy
    (2023-01-01) ŞAHİN, ÖZLEM; SEVİK, MEHMET ORKUN; ÇAM, FURKAN; DERİCİOĞLU, VOLKAN; SEVİK M. O., Aykut A., ÇAM F., DERİCİOĞLU V., ŞAHİN Ö.
    Purpose: This study aimed to evaluate the choroidal vascularity index (CVI) as an activity criterion in chronic central serous chorioretinopathy (CSC) and as a measure of treatment response after full-dose-full-fluence photodynamic therapy (fd-ff-PDT). Methods: This fellow-eye-controlled, retrospective cohort study included 23 patients with unilateral chronic CSC treated with fd-ff-PDT (6 mg/m2; 50 μcm2; 83 s). Subfoveal choroidal thickness (SFCT, μm) and CVI (%) of the affected and fellow eyes at baseline as well as at 1, 3 and 6 months after fd-ff-PDT were compared. Results: The patients\" mean age was 43.4 ± 7.3 years, and 18 (78.3%) were male. CVI was comparable between the affected and fellow eyes at baseline (66.09 ± 1.56 vs. 65.84 ± 1.57, p = 0.59). However, it became significantly lower in the affected eyes 1 (64.45 ± 1.68 vs. 65.87 ± 1.19, p = 0.002), 3 (64.21 ± 2.08 vs. 65.71 ± 1.59, p = 0.009) and 6 (64.47 ± 2.19 vs. 65.62 ± 1.52, p = 0.045) months after fd-ff-PDT. The mean SFCT and the mean CVI were significantly decreased in the affected eyes at all follow-up visits compared with baseline after fd-ff-PDT (p < 0.001). Conclusion: At baseline, CVI was comparable between affected and fellow eyes. Therefore, its use as an activity criterion in chronic CSC patients is questionable. However, it was significantly decreased in fd-ff-PDT-treated eyes, supporting its role as a measure of treatment response in chronic CSC.
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    PublicationOpen Access
    Effect of age on primary balloon dacryocystoplasty and probing success in congenital nasolacrimal duct obstruction
    (2022-11-01) ÇERMAN, EREN; SEVİK, MEHMET ORKUN; ERASLAN, MUHSİN; DERİCİOĞLU, VOLKAN; DERİCİOĞLU V., Sevik M. O., Sacu S. S., ERASLAN M., ÇERMAN E.
    Purpose To compare the success rates of balloon dacryocystoplasty (BDP) and probing as a primary procedure in congenital nasolacrimal duct obstruction (CNLDO) and investigate the effect of age on both procedures. Methods A total of 135 patients (171 eyes) with simple and incomplete complex CNLDO were included in this retrospective study; complete complex CNLDO cases were excluded. The success rates for primary BDP (118 eyes) and for probing (53 eyes) were compared overall and among the age groups; Group 1 (12-24 months old), Group 2 (25-36 months old), and Group 3 (> 36 months old). Results Mean age of the patients was 41.5 +/- 27.2 months for primary BDP, and 21.8 +/- 10.8 months for probing (p < 0.001). Overall success rates for primary BDP and probing were 81.1% (43/53) and 76.3% (90/118), respectively (p = 0.481). Success rates for BDP and probing among age groups were 93.8% and 85.3% in Group 1 (p = 0.360), 93.3% and 50.0% in Group 2 (p = 0.012), and 63.6% and 27.3% in Group 3 (p = 0.052), respectively. Cox regression analysis showed that the median ages were 18 months for probing and 36 months for primary BDP. The Poisson regression model showed that for every 1-month increase in patients\" age, the success rate of probing decreased by 9.7%. Conclusion Probing success decreased to a point where different treatment options such as primary BDP can be discussed with the patients\" parents after 18 months of age. The success of BDP decreased after 36 months, while it maintained a high success rate between 24 and 36 months as primary treatment.