Clinical Profile of Non Strabismic Binocular Vision Anomalies in MBBS and Nursing Students in a Teaching Hospital: A Cross-sectional Study

Abstract

Introduction: Bachelor of Medicine and Bachelor of Surgery (MBBS) and nursing students spend a lot of time in near vision activities daily while studying. In the Coronavirus Disease-2019 (COVID-19) and post pandemic era, the emphasis on electronic teaching and studying has increased immensely. Students have started depending more on online studying, teaching and search for study material leading to more time being spent using electronic devices like mobile phones, tabs, Personal Computer (PC), etc. This can lead to lot of eye strain (digital eye strain) and this predisposes them to develop Non Strabismic Binocular Vision Anomalies (NSBVA) related to accommodation and convergence of eyes. Aim: To study prevalence of NSBVA and report associated ocular symptoms and association of electronic devices (mobile, laptop) use with prevalence NSBVA, in MBBS and nursing students of a teaching hospital in Western Maharashtra. Materials and Methods: This study was a cross-sectional observational study conducted between November 2020 to April 2021 at Rajiv Gandhi Medical College and CSM Hospital, Thane, Maharashtra, India. In this study, a total of 110 students including both MBBS and nursing students from all academic years of the hospital were examined for a comprehensive ophthalmic examination and complete binocular vision assessment. The prevalence of NSBVA, associated ocular symptoms, prevalence of refractive errors and duration of electronic device use in the students was documented. Student’s t-test was used to compare the total daily duration of electronic devices (mobile, laptop, computer tablets) use between students with and without NSBVA. Chi-square test was used to find association of variables duration of electronic device use and occurrence of NSBVA. Results: Out of 110 students examined, there were 37.27% (n=41) were males and 62.72% (n=69) females. Age range was 18-30 years with mean age 21.85±2.67 years. Overall, 47 (42.72%) students had NSBVA including 34 MBBS and 13 nursing students. 12 (11%) students had ocular symptoms with NSBVA while 35 (31.8%) students had NSBVA without any ocular symptom. Eye strain was the most common ocular symptom. Average electronic device use was 4.53 hours/day. Most used electronic device was mobile phone. There was no association between NSBVA and electronic device use. Conclusion: The NSBVA is highly prevalent among MBBS and nursing students. Ocular symptoms are absent in many students with NSBVA which may lead to delayed diagnosis and worsening of ocular symptoms due to NSBVA. Older age group of students have higher prevalence of NSBVA. Electronic device exposure is not significantly associated with NSBVA in these students. Screening of such at risk population is important for timely diagnosis and treatment of NSBVA.

Keywords

• accommodation excess
• convergence insufficiency
• electronic device
• eye strain