Evaluation of Retinal and Optic Nerve Changes in Epilepsy Patients Using Antiepileptic Drugs with Optical Coherence Tomography Angiography (OCTA)

Abstract

Background: Epilepsy is a chronic neurological disease characterized by seizures, and it is also suggested that intracranial pressure increase during seizures, hypoxia caused by respiratory insufficiency, or antiepileptic drugs used for treatment purposes have many effects on the optic nerve. In this study, it is aimed to evaluate the effects of antiepileptic drug use on retinal and optic nerve blood flow in epilepsy patients with OCTA. Materials and Methods: The study was planned prospectively. Volunteers who met the inclusion criteria were divided into 2 groups as Epilepsy group (Group E), Control group (Group C). After detailed neurological and eye examinations, optical coherence tomography-angiography (OCTA) measurements were performed. Results: No statistically significant difference was found between the two groups in terms of age and gender (p=0.311, p=0.114). In Group E, 21 patients (70%) were receiving single drug therapy and 9 patients (30%) were receiving multidrug therapy. In Group E; the foveal thickness was measured as 232.0 (190-525(min-max)) and parafoveal thickness was measured as 304.0 (220-336(min-max)) in group C. The foveal thickness was measured as 251.5 (211-303(min-max )) and parafoveal thickness was measured as 319.0 (290-363(min-max)), and the difference was statistically significant (respectively; p=0.036; p=0.020). Superior hemi-area thickness in group E is 306.0 (238-336(min-max)), inferior hemi-area thickness is 307.9±15.19, superior quadrant thickness is 312.6±15.8, nasal quad-rant thickness is 310.3±15.6, inferior quadrant thickness is 310.3±14.6; superior hemi-area thickness was measured as 319.5 (293-373(min- max)), inferior hemi-area thickness was measured as 316.2±15.0, supeior quadrant thickness was measured as 322.7±17.6, nasal quadrant thickness was measured as 319.9±14.8, inferior quadrant thickness was measured as 319.9±14.8 in group C, and the difference was statistically significant (respectively; p=0.010; p=0.037; p=0.023; p=0.017; p=0.039). There was no statistically signifi-cant difference between the groups in terms of superficial and deep layer vascular densities and flow areas of the retina, and superfi-cial and deep layer vascular densities of the optic nerve decussation. In addition, foveal and parafoveal retinal thickness showed similar effects in single-multidrug treatment, and no statistically significant difference was found. Conclusions: In OCTA measurements, no changes were detected in the retinal microcirculation in epilepsy patients under treatment, but a decrease in foveal and parafoveal thickness was detected. In the later stages of epilepsy, the retina and optic nerve may be affected due to various mechanisms, and these patients may require joint follow-up and treatment planning in both neurology and ophthalmology clinics

Keywords

• Antiepileptics
• Epilepsy
• Optical Coherence Tomography Angiography
• Retinal Microcirculation
• Retinal Thickness

Antiepileptik Kullanan Epilepsi Hastalarının Retina ve Optik Sinir Değişikliklerinin Optik Koherens Tomografi Anjiografi (OKTA) İle Değerlendirilmesi

Abstract

Amaç: Epilepsi nöbetlerle karakterize kronik nörolojik bir hastalık olup; nöbetler sırasında oluşan intrakraniyal basınç artışı, respiratuar yetmezlik sonucu gelişen hipoksi ya da tedavi amacıyla kullanılan antiepileptik ilaçların optik sinir üzerine etkilerinin olduğu düşünülmektedir. Çalışmada, epilepsi hastalarında antiepileptik ilaç kullanımının retinal ve optik sinir kan akımına etkilerinin OKTA ile değerlendirilmesi amaçlanmaktadır. Materyal ve Metod: Çalışma prospektif olarak planlandı. Dahil edilme kriterlerini karşılayan gönüllüler; Epilepsi grubu (Grup E), Kontrol grubu (Grup K) olarak 2 gruba ayrıldı. Ayrıntılı nörolojik ve göz muayenelerini takiben optik koherens tomografi-anjiografi (OKTA) ölçümleri yapıldı. Bulgular: Her iki grup arasında yaş ve cinsiyet açısından istatistiksel olarak anlamlı bir fark bulunmadı (p=0.311, p=0.114). Grup E’de 21 hasta ( %70) tek, 9 hasta (%30) çoklu ilaç tedavisi alıyordu. Grup E’de; foveal kalınlık 232.0 (190-525(min-maks)) ve parafoveal kalınlık 304.0 (220-336(min-maks)) Grup K’da foveal kalınlık 251.5 (211-303(min-maks)) ve parafoveal kalınlık 319.0 (290-363(min-maks)) olarak ölçülmüş olup aradaki fark istatistiksel olarak anlamlıydı (sırasıyla; p=0.036; p=0.020). Grup E’de üst yarı alan kalınlığı 306.0 (238-336(min-maks)), alt yarı alan kalınlığı 307.9±15.19, üst kadran kalınlığı 312.6±15.8, nazal kadran kalınlığı 310.3±15.6, alt kadran kalınlığı 310.3±14.6; Grup K’da üst yarı alan kalınlığı 319.5 (293-373( min- maks)), alt yarı alan kalınlığı 316.2±15.0, üst kadran kalınlığı 322.7±17.6, nazal kadran kalınlığı 319.9±14.8, alt kadran kalınlığı 319.9±14.8 olarak ölçülmüş olup aradaki fark istatistiksel olarak anlam-lıydı (sırasıyla; p=0.010; p=0.037; p=0.023; p=0.017; p=0.039). Retinanın yüzeyel ve derin tabaka damar yoğunlukları ve akım alanları ile optik sinir başı yüzeyel ve derin tabaka damar yoğunlukları açısından gruplar arasında istatistiksel olarak anlamlı bir fark saptanmadı. Ayrıca foveal ve parafoveal retina kalınlık, tekli-çoklu ilaç tedavisinde benzer etkilenme göstermiş olup istatistiksel olarak anlamlı bir fark saptanmadı. Sonuç: OKTA ölçümlerinde tedavi altındaki epilepsi hastalarında retinal mikrosirkülasyonda değişiklik saptanmadı ancak foveal ve parafoveal kalınlıkta azalma tespit edildi. Epilepsinin ilerleyen dönemlerinde çeşitli mekanizmalara bağlı olarak retina ve optik sinir etkilenebilir ve bu hastaların hem nöroloji hem de oftalmoloji kliniklerinde takip ve tedavi sürecinin birlikte planlamasını gerektirebilir.

Keywords

• Antiepileptikler
• Epilepsi
• Optik Koherens Tomografi Anjiografi
• Retinal Mikrosirkülasyon
• Retina Kalınlığı

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