A 40-year-old man with recurrent episodes of transverse myelitis and optic neuritis gradually developed diplopia to lateral gaze bilaterally, which was not fatigable. Deep tendon reflexes (DTRs) including jaw jerk were brisk.

Challenge Question
The following is (are) correct regarding the video findings:
1. Internuclear ophthalmoplegia (INO)
2. The side of the INO is named after the abducted eye.
3. Bilateral lesion of medial longitudinal fasciculus (MLF)
4. Pathognomonic of multiple sclerosis (MS)
5. A complication of treatment of MS

Find the answer and diagnosis in the next edition of Practical Neurology or online, posted along with the patient video at PracticalNeurology.com.

Case selected from Dr. Shaibani's Video Atlas of Neuromuscular Diseases, in press, by Oxford University Press. Aziz Shaibani, MD, FACP, FAAN is Director of Nerve & Muscle Center of Texas and Clinical Associate Professor of Medicine at Baylor College of Medicine in Houston, TX. He is also Adjunct Professor of Neurology at Kansas University Medical Center in Kansas City, Kansas.