Keywords
thalamic - hemorrhage - bilateral - head trauma
Introduction
The thalamus is one of the areas site most affected by intra-cerebral hemorrhage.[1]
[2]
[3] Hypertension and diabetes mellitus, as well as antiaggregant and anticoagulant usage, are some of the risk factors for thalamic bleeding.[4] However, bilateral thalamic hematoma after trauma is extremely rare. The authors present a case of symmetrical and bilateral thalamic hemorrhage with a literature review.
Case Report
A 27-year-old man was admitted to the hospital following a head trauma. Initial neurologic evaluation revealed a comatose patient with a score of Glasgow 3/15, bilateral mydriasis unresponsive, and absence of brainstem reflexes. His computed tomography (CT) of the brain ([Figs. 1], [2]) showed a bilateral thalamic hemorrhage, intraventricular hemorrhage, and cerebral edema without hydrocephalus. The patient died 48 hours after admission.
Fig. 1 Axial section of a brain scan showing bilateral thalamic hematoma.
Fig. 2 Coronal section of a brain scan showing bilateral thalamic hematoma, producing a mirror image.
Discussion
The prevalence of thalamic hemorrhage in different series of primary intracerebral hemorrhage vary widely from 6% in the series of Juvela[5] to 15.7% in the series of Tatu et al.[6] However, the general incidence of traumatic basal ganglia hemorrhage is reported between 2.4 and 3% of closed head injury.[7] The incidence is higher in postmortem studies (9.8%).[7]
Bilateral thalamic bleeding occurs mainly due to methanol intoxication, coagulopathies, vasculitis, and infection. Primary hypertensive thalamic hemorrhage is usually unilateral.[8]
Traumatic intracerebral hemorrhage occurs usually at the tip of frontal and temporal poles because of closeness to bony parts, but the thalamic seat is an uncommon clinical and radiologic presentation.[9]
The mechanism is unclear though it is proposed to arise from shear strain of the lenticulostriate or anterior choroidal vessels caused by acceleration/deceleration forces at the time of injury.[9] Both coup and counter coup injuries can cause this and this may cause bilateral lesions.[9]
Thalamic hemorrhage can occur by different clinical profiles (sensorimotor disturbances, speech disorders, lacunar syndrome). Diagnosis is easy to install on a CT of the brain, and in this case, we found a bilateral thalamic hematoma producing a mirror image.
Thalamic hemorrhage is a severe clinical condition. The initial level of consciousness was always found to be a predictor of mortality in the different series.[10]
Conclusion
Thalamus may be the seat of posttraumatic bleeding with even a bilateral and symmetrical location.
