A Five-year Retrospective Study on the Clinical Profile of Myasthenia Gravis with Ocular Involvement in a Tertiary Hospital

Abstract

Introduction: Myasthenia Gravis (MG) with ocular involvement has an elusive diagnosis. Ptosis and Diplopia are the most common and early presenting features of MG. Acetylcholine receptor (AChR) antibody titre, Nerve conduction studies and chest imaging are important diagnostic tests for MG. A simple test like an ice pack test can help in differentiating MG from other causes of neurological ptosis and other symptoms. Aim: To study the systemic presentation, the profile of ocular involvement, clinical and laboratory tests and treatment modalities used in patients diagnosed with MG in a tertiary hospital. Materials and Methods: This was a hospital based five year retrospective study of 14 cases of MG, diagnosed and treated between January 2012 and December 2016. Analysis of presenting signs and symptoms of generalised and ocular MG was done. Profile of diagnostic clinical, laboratory, and radiological tests performed for each patient and their results were noted and analysed. Various treatment modalities used to manage the cases were noted. Permission from the Institutional Ethics committee was taken prior to starting the study. SPSS software version 23 was used for data analysis. Results: Mean age of presentation was found to be 40.2 years with a predilection for male gender; 81.71% of patients, who presented with Generalised MG, 14.2% had ocular involvement. Ptosis was found to be the most common ocular symptom in combination with diplopia (SD-0.554). Lateral rectus was most commonly involved muscle. Ice pack test, nerve conduction studies were specific in diagnosis of MG. Antibody titres were positive in 66.6% patients. About 30% patients underwent HRCT chest out of which 60% showed some Thymus involvement. Various forms of treatment were used including oral Pyridostigmine, oral steroids and oral immunosuppressants. Conclusion: The pattern of involvement in MG in this study was slightly different. The mean age was lower, there was preponderance of male gender and lateral rectus muscle was most commonly involved muscle. A simple ice pack test is cheap and reliable test to diagnose MG with ocular involvement. We suggest HRCT to rule out thymic abnormalities.

Keywords

• ice pack test
• myogenic ptosis
• nerve conduction studies
• serology in myasthenia