Atypical Sensory Loss Pattern in an Isolated Thalamic Stroke: A Case Report

Abstract

This case report discusses a 51-year-old male who presented to the emergency department (ED) with left-sided hemiparesthesia and left leg incoordination. The initial brain computed tomography (CT) scan was negative, and the follow-up brain CT three days after the onset of symptoms was also negative. Although sensitivity and specificity are not 100%, CT remains the first-line diagnostic test for detecting a cerebrovascular accident (CVA). In this unique case, CT was not sufficient. Following two negative CT scans, magnetic resonance imaging (MRI) finally revealed the cause of this patient's symptoms, an ischemic incident in the right thalamus. Thalamic strokes typically present with contralateral hemiparesis and hemisensory loss, unreactive pupils, and gaze palsy with gaze deviation away from the side of the infarct. It is unusual to see a thalamic lesion present with pure hemiparesthesia without facial involvement. This patient's clinical presentation is discussed, as well as future investigations and ways to prevent this diagnostic delay. This case demonstrates the importance of follow-up imaging based on the clinical presentation of potentially subtle imaging findings.

Keywords: atypical thalamic stroke; cerebrovascular accident; computed tomography imaging; ischemic stroke; magnetic resonance imaging; thalamic stroke.

Figure 1. CT of the brain without contrast

Initial negative brain CT showing no evidence of vessel occlusion, hemorrhage, or mass effect.

Figure 2. Axial T2 MRI of the brain without contrast