Differential Diagnosis
- Single most likely diagnosis
- Acute ischemic stroke: The patient's presentation with acute right-sided numbness, diplopia, and MRI findings of subcortical deep white matter low T1 and T2/FLAIR hyperintensity in the left parietal lobe, right basal ganglia, and pons/medulla with restricted diffusion is highly suggestive of an acute ischemic stroke. The patient's lack of known risk factors such as diabetes or hypertension does not rule out this diagnosis, as stroke can occur in the absence of these conditions.
- Other Likely diagnoses
- Multiple sclerosis (MS): The patient's symptoms of numbness and diplopia, combined with the presence of multiple lesions in the brain on MRI, could suggest a diagnosis of MS. However, the acute onset of symptoms and the presence of restricted diffusion on MRI make this diagnosis less likely.
- Vasculitis: The patient's presentation with multiple lesions in the brain and the absence of known risk factors for stroke could suggest a diagnosis of vasculitis, such as primary central nervous system vasculitis. However, this diagnosis would require further evaluation and testing to confirm.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Posterior reversible encephalopathy syndrome (PRES): Although the patient's symptoms and MRI findings do not strongly suggest PRES, this diagnosis should be considered due to its potential for severe consequences if left untreated. PRES is often associated with hypertension, but it can occur in the absence of this condition.
- Cerebral venous sinus thrombosis: This diagnosis should be considered due to its potential for severe consequences if left untreated. The patient's symptoms and MRI findings do not strongly suggest this diagnosis, but it should be ruled out with further evaluation and testing.
- Rare diagnoses
- Susac syndrome: This rare condition is characterized by microangiopathic changes in the brain, retina, and cochlea. The patient's symptoms of numbness and diplopia, combined with the presence of multiple lesions in the brain on MRI, could suggest this diagnosis. However, further evaluation and testing would be required to confirm.
- Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS): This rare condition is characterized by recurrent episodes of stroke-like symptoms, including numbness and visual disturbances. The patient's symptoms and MRI findings could suggest this diagnosis, but further evaluation and testing would be required to confirm.