250A CASE REPORT OF A THALAMO-MESENCEPHALIC STROKE IN AN HIV-POSITIVE PATIENTA 62-year-old male with an unusual eye movement in 2017. Unilateral thalamomesencephalic stroke (TMS) generated a vertical one-and-a-half syndrome in this patient1. Other authors have previously observed anomalies in eye movements, such as bilateral vertical gaze palsy, as a result of a unilateral rostral midbrain stroke. The anatomical circulation of the brain is complicated and varied, and variations in the circle of Willis might include component absence or fusion, incomplete processes, fenestrations, fetal branches, as well as asymmetry and duplication. A 41-year-old female arrived with a 5-day history of inability to open the right eye, which was accompanied with impaired vision in the right eye, which progressed to bilateral diplopia. The patient also claimed being unable to balance herself and walking unaided. There was no history of trauma, heavy NSAID usage, contraception, vitamin supplement use, or headache complaints. The patient did not smoke, drink alcohol, or engage in any other form of recreational or illicit drug usage. We present a case of right sided TMS in a 41-year-old lady. Unilateral TMS is uncommon, and its prevalence is unknown, although one study found that it accounts for roughly 0.6 percent to 1 percent of midbrain ischemic strokes and is frequently associated with other posterior circulation infarcts. To the best of our knowledge, this is the first patient to be diagnosed with unilateral TMS related to HIV vasculitis, with bilateral Babinski symptoms and no thalamic symptoms. It has been reported in the medical literature. HIV vasculitis is one of the causes of unilateral TMS in young patients. To be considered are etiological diagnosis. Nonetheless, we advocate a comprehensive investigation based on a number of cases to back this up postulateAnilKumarMuthineni@gmail.comResearch732017Pregnancy,Thalamo-Mesencephalic Stroke,HIVAnil Kumar MuthineniDepartment of General Medicine, Sri Lakshmi Narayana Institute of Medical Sciences, Puducherry – 605502, India