A case of germinoma originating in the basal ganglia and thalamus is presented. This tumour most commonly originates during childhood and adolescence, at pineal and suprasellar regions. In the early stages, the diagnosis of germinoma in the basal ganglion and thalamus is difficult because of its rarity and non-specific findings. The computed tomography (CT) and magnetic resonance imaging (MRI) findings though non-diagnostic, are discussed here. A few differential diagnoses had been discussed with radiological abnormality. Open biopsy done in this case proved to be two-cell pattern germinoma. Early detection of the tumour is desirable, since this tumour is highly sensitive to radio and chemotherapy and is potentially curable. Our patient was treated with combined chemotherapy and the response was well and no residual tumour or recurrence was seen on the repeated imaging modality, however his neurological deficits remained unchanged.
Japanese encephalitis (JE) is a known CNS viral infection that often involves the thalamus early. To investigate the possible role of sensory peripheral nervous system (PNS) in early neuroinvasion, we developed a left hindlimb footpad-inoculation mouse model to recapitulate human infection by a mosquito bite. A 1-5 days postinfection (dpi) study, demonstrated focal viral antigens/RNA in contralateral thalamic neurons at 3 dpi in 50% of the animals. From 4 to 5 dpi, gradual increase in viral antigens/RNA was observed in bilateral thalami, somatosensory, and piriform cortices, and then the entire CNS. Infection of neuronal bodies and adjacent nerves in dorsal root ganglia (DRGs), trigeminal ganglia, and autonomic ganglia (intestine, etc.) was also observed from 5 dpi. Infection of explant organotypic whole brain slice cultures demonstrated no viral predilection for the thalamus, while DRG and intestinal ganglia organotypic cultures confirmed sensory and autonomic ganglia susceptibility to infection, respectively. Early thalamus and sensory-associated cortex involvement suggest an important role for sensory pathways in neuroinvasion. Our results suggest that JE virus neuronotropism is much more extensive than previously known, and that the sensory PNS and autonomic system are susceptible to infection.
Gamma knife thalamotomy (GKT) has been used as a therapeutic option for patients with disabling tremor refractory to medications. Impressive improvement of tremor has been reported in the neurosurgical literature, but the reliability of such data has been questioned.