Germinomas are highly immunogenic tumors eliciting a strong peri-tumoral immune response that can spillover into the surrounding healthy tissues. This phenomenon can also occur in intracranial germinomas, manifesting as secondary hypophysitis. Herein, we report a case of 12-year-old-girl presenting with polyuria and polydispsia. She had central diabetes insipidus (CDI) and panhypopituitarism. Imaging revealed a sellar-suprasellar mass with infundibular stalk thickening. Transphenoidal biopsy revealed epithelioid granulomas with immunostaining negative for germinomatous cells. Other causes of hypophysitis were ruled out. Accordingly, she was diagnosed as primary granulomatous hypophysitis and treated with high-dose corticosteroids. Three years later she again presented with headache, vomiting and diminution of vision. Imaging showed a heterogeneous, solid-cystic peripheral rim-enhancing lesion at the same location with involvement of hypothalamus, ependyma and pineal gland. Cerebrospinal fluid beta-human chorionic gonadotropin was markedly elevated, confirming the diagnosis of an intracranial germ cell tumor. She was started on chemotherapy; however, she succumbed to febrile neutropenia. We performed a literature search and found 18 anecdotal cases of secondary hypophysitis associated with intracranial germinomas. There was a slight male preponderance (male:female 5:4). Two-thirds of the cases were below 18 years of age. Polyuria was the most common presenting manifestation (83%). CDI and panhypopituitarism were seen in 89 and 78% cases, respectively. Imaging evidence of pituitary stalk thickening was seen in 12 cases (67%), while pituitary enlargement and/or sellar mass were reported in 11 cases (61%). Pineal involvement was extremely rare, being reported in only 1 case, implying the predilection of suprasellar (rather than pineal) germinomas in causing secondary hypophysitis. Histologically, 82% had lymphocytic hypophysitis, while 18% had granulomatous hypophysitis. Initially, the diagnosis of germinoma was missed in 60% of the cases who were wrongly treated with corticosteroids. To conclude, physicians should make it a dictum that all children and adolescents presenting with CDI and pituitary stalk thickening should be rigorously screened for an underlying intracranial germinoma before labeling them as primary hypophysitis.

Occlusion of both the limbs of accessory middle cerebral artery (AMCA) poses a unique challenge in management of acute ischaemic stroke by mechanical thrombectomy. The patient is a 30-year-old man, presenting with acute onset of left-sided hemiparesis for 4 hours. Non-contrast CT brain showed no bleed and three-dimensional CT angiogram of head and neck vessels showed dissection involving right carotid bulb and tandem occlusion of right MCA with presence of two MCA stumps. Aspiration thrombectomy was done using a reperfusion catheter, advanced separately into both the MCA stumps and complete recanalisation of both the limbs of MCAs was achieved, which was found to be AMCA. Balloon angioplasty for the internal carotid artery dissection was performed. Although occlusion of AMCA in acute ischaemic stroke is a chance occurrence, it is important to identify this variant as recanalisation of both the limbs by mechanical thrombectomy is required for favourable outcome after the procedure.

Background and purposes Minimal hepatic encephalopathy (MHE) has no recognizable clinical symptoms, but patients have cognitive and psychomotor deficits. Hyperammonemia along with neuroinflammation lead to microstructural changes in cerebral parenchyma. Changes at conventional imaging are detected usually at the overt clinical stage, but microstructural alterations by advanced magnetic resonance imaging techniques can be detected at an early stage. Materials and methods Whole brain diffusion kurtosis imaging (DKI) data acquired at 3T was analyzed to investigate microstructural parenchymal changes in 15 patients with MHE and compared with 15 age- and sex-matched controls. DKI parametric maps, namely kurtosis fractional anisotropy (kFA), mean kurtosis (MK), axial kurtosis (AK) and radial kurtosis (RK), were evaluated at 64 white matter (WM) and gray matter (GM) regions of interest (ROIs) in the whole brain and correlated with the psychometric hepatic encephalopathy score (PHES). Results The MHE group showed a decrease in kFA and AK across the whole brain, whereas MK and RK decreased in WM ROIs but increased in several cortical and deep GM ROIs. These alterations were consistent with brain regions involved in cognitive function. Significant moderate to strong correlations (–0.52 to –0.66; 0.56) between RK, MK and kFA kurtosis metrics and PHES were observed. Conclusion DKI parameters show extensive microstructural brain abnormalities in MHE with minor correlation between the severity of tissue damage and psychometric scores.

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Toxic encephalopathy is an important differential diagnosis in a child with encephalopathy and seizures. Subtle circumstantial evidence and apt neuroimaging features can significantly contribute to management, especially in a case of accidental exposure. 2, 4-D (ethyl ester) poisoning is a rare diagnosis, despite the common usage of this toxic compound as weedicide in northern India. The clinical similarity to the anticholinesterase poisoning, especially in the setting of agrochemical exposure is the main cause of under-diagnosis with usually fatal outcomes. We present an interesting case of accidental 2, 4-D (ethyl ester) poisoning in a child with typical neuroimaging features. A review of the literature regarding neuroimaging patterns of bilaterally symmetrical signal abnormalities involving basal ganglia in brain magnetic resonance imaging (MRI) from the point of view of clinical significance, is also discussed.