A 27-year-old man has had right arm numbness for about 2 weeks. He describes the sensation as “a heavy feeling.” Initially, the sensation was intermittent, but now it is stable. He denies any weakness, pain, coordination problems, or visual changes.
He is a psychologist and has been functioning well at work. He has no limitations in driving. He does not typically engage in physical activities such as sports, and he has not noticed any changes in his ability to carry out his usual activities.
The patient was involved in a motor vehicle accident as a teenager and sustained a fracture of several bones in his foot. This injury healed well without surgery.
His parents are both in their 40s and healthy.
The patient is alert, oriented, and cooperative. No involuntary jerks or tremors are noted during the examination. His skin is normal, without discoloration, rashes, lesions, or bruises.
Vital signs are all normal. Breath sounds are normal and regular, pulse is normal and regular, and heart rhythm is normal without any murmurs. His abdomen is non-tender and non-distended.
The patient’s extraocular movements are normal without any nystagmus or limitations of movement. He does not have diplopia or a visual field cut. His visual acuity is not impaired.
His motor strength is 5/5 in all extremities with the exception of his right arm. His biceps and triceps are slightly weak with strength of 4+/5. His right hand strength is normal. His right upper extremity reflexes are brisk, and his reflexes are normal in his other extremities. His sensory examination is normal to light touch, pinprick, position, and vibration in all extremities, including the right upper extremity. His gait is normal, and he can do a tandem walk and Romberg test without difficulty.
The patient was sent for a brain MRI scan with gadolinium, which showed a small dense lesion in the left internal capsule. No other lesions were visible on his brain imaging study, and no edema was noted. He received a diagnosis of ischemic stroke, and tests were ordered to determine the cause.
The results of an electrocardiogram, an echocardiogram, and brain and neck magnetic resonance angiography were all normal. The patient had an extensive blood workup, including a complete blood cell (CBC) count with differential; antinuclear antibody and thyroid tests; liver function tests; and measurement of protein C, protein S, factor V Leiden, anticardiolipin antibodies, lupus anticoagulant, and fibrinogen levels—all of which were normal.
What do you suspect caused this patient’s lesion and symptoms? >>
1. Diener HC, Sacco RL, Easton JD, et al. Dabigatran for prevention of stroke after embolic stroke of undetermined source. N Engl J Med. 2019;380:1906-1917. doi: 10.1056/NEJMoa1813959.
2. Hart RG, Sharma M, Mundl H, et al. Rivaroxaban for stroke prevention after embolic stroke of undetermined source. N Engl J Med. 2018;378:2191-2201. doi: 10.1056/NEJMoa1802686. [Epub 2018 May 16].