Thrombosis of the deep cerebral venous system in the absence of superficial sinus thrombosis is a very rare disease. The clinical and radiological findings can be diagnostically challenging due to the subtle appearances on computed tomography (CT) scan. Magnetic resonance imaging (MRI) examination is a preferred imaging modality to complement the CT findings for an accurate diagnosis of venous sinus thrombosis. We present a case of this unusual condition which present as unilateral thalamic lesion on CT scan and the role of contrast enhanced MRI with fast spoiled gradient echo (FSPGR) sequence and 3D reconstruction which led to the diagnosis of thrombosis in the deep cerebral venous system.
Thrombosis

Tolosa-Hunt syndrome is typically associated with an infl ammatory lesion in the cavernous sinus or orbital fi ssure, often requiring steroids for symptom resolution. In this report, we describe a case of Tolosa-Hunt syndrome preceded by several years’ history of idiopathic recurrent facial palsies. The spontaneous resolution of THS in our case as well as prior facial nerve involvement supports the hypothesis that Tolosa-Hunt syndrome is part of a spectrum of idiopathic recurrent cranial neuropathy.

Medulloblastoma is the most common form of childhood primary brain tumour arising from the cerebellar vermis. It is classified as WHO grade IV embryonal tumours and currently at least four histological variants have been established. Only few case reports been published on the imaging features of the medulloblastoma with excessive nodularity variant. We report the MRI features of a rare case of medulloblastoma with excessive nodularity in a child which is confirmed by histopathology.

This is a case of an adult patient with hypertensive intraventricular haemorrhages complicated by hydrocephalus that failed to respond to endoscopic third ventriculostomy (ETV). High-resolution 3D Fast Imaging Employing Steady State Acquisition (FIESTA) magnetic resonance imaging (MRI) revealed underlying multiloculated hydrocephalus. This case report highlights the appropriate sequence and its attributes that offer adequate preoperative information detailing the ventricular system.

A 27 year-old Chinese man, involved in a motor vehicle accident, presented with rapidly progressive pseudobulbar palsy and spastic tetraplegia. Magnetic resonance imaging (MRI) of the brain showed central pontine T2 hyperintensity with an unaffected outer rim, consistent with central pontine myelinolysis. There was no hyponatraemia before MRI and he was neither an alcoholic nor malnourished. Cerebral angiogram confi rmed the diagnosis of right vertebral artery dissection. Vertebral artery dissection should be considered in a case with imaging suggestive of central pontine myelinolysis.

Aged ; Brain Neoplasms ; diagnosis ; pathology ; Central Nervous System Neoplasms ; diagnosis ; pathology ; Fatal Outcome ; Female ; Humans ; Lymphoma ; diagnosis ; pathology ; Meningeal Neoplasms ; diagnosis ; secondary

Objective: To delineate and differentiate between late subacute hemorrhage and intracranial lipomas in clinically available conventional and advanced MR sequences. Methods: Two cases of late subacute hemorrhage and two cases of intracranial lipoma were reviewed with CT scans and 3.0T scanner MRI. The sequences evaluated in MRI were T1-weighted (T1W) fast spin echo (FSE), T2-weighted (T2W) FSE, gradient echo T2*-weighted (GRE T2*W) images, diffusion weighted (DWI), apparent diffusion coefficient (ADC) and multivoxel spectroscopy. Results: Late subacute hemorrhage and intracranial lipoma have similar imaging features on T1W, T2W FSE with blooming artefact at the margins on GRE T2*W. However on GRE T2*W sequence, the central area of lipoma demonstrates low signal; while hemorrhage demonstrates high signal. In DWI, late subacute hemorrhage shows hyperintensity; while in lipoma there is loss of signal. Conclusion: Awareness of the potential pitfalls in standard sequence are important, as these entities appear to have similar T1W/ T2W characteristic with blooming artefact on T2*W. Knowing the distinctive central signal intensity pattern on GRE T2W* and DWI is therefore essential to differentiate between these lesions as there are differences to their clinical management.
Magnetic Resonance Imaging

Increase in cross-sectional muscle area of major muscle groups associated by heavy resistance training has been well documented. However, there has been no published article of changes in the inferior orbicularis oculi muscle when heavy resistance training is applied. We present a case of inferior orbicularis hypertrophy detected on MRI in a gentleman who practised heavy resistance training using his lower eyelids.

Objectives: To investigate the accuracy of multidetector computed tomography venography (MDCTV) and magnetic resonance venography (MRV) of differing fi eld strength in diagnosing cerebral venous sinus thrombosis (CVST). To assess the visualization rate of the cerebral veins and dural sinuses between these imaging modalities. Methods: A retrospective review of 27 patients with clinical suspicion of CVST who underwent both MDCTV and corresponding MRI/MRV brain scans at 0.35T, 1.5T or 3.0T fi eld-strength were performed. Results were compared with the defi nitive fi nal diagnosis. In the nonthrombotic group of patients, a descriptive study of the anatomical visualization of cerebral veins and dural sinuses was also undertaken. Results: Ten of the 27 patients had a fi nal diagnosis of CVST. The Neuroradiologists’ consensus reading identifi ed these 10 cases of CVST in both the MDCTV and MRV scans with a sensitivity rate of 100%. There was one false positive in MDCTV and three false-positives in the MRV group (1.5T) with positive predictive values of 90.9% and 76.9%, respectively. MDCTV and MRV demonstrated a specifi city of 94.1% and 82.4%, respectively in diagnosing CVST. No false negative images were seen demonstrating a negative predictive value of 100% in both modalities. There was no statistical difference in the anatomical visualization rate of the cerebral veins or the dural sinuses among the various strengths of MRI. However, statistically signifi cant (p<0.05) fewer visualised vessels in MRV compared to MDCTV, for the SSS, ISS, straight sinus, ICV and VOG. Conclusion: MDCTV is equal to MRV of various strength in its sensitivity for CVST diagnosis. MDCTV also provides better anatomical visualization of the dural sinuses and cerebral veins.

Measles virus causes three distinct neurological syndromes: acute disseminated encephalomyelitis, subacute sclerosing panencephalitis and the rare subacute measles encephalitis, or inclusion body measles encephalitis. There is a current debate of whether subacute measles encephalitis is an opportunistic infection or a subacute infection caused by a mutated measles strain. There is also no report of long term MRI of survivor. We reported a young Chinese girl with a history of relapsed acute lymphoblastic leukaemia and subacute measles encephalitis confirmed by brain biopsy who survived. Serial magnetic resonance imaging of the brain showed cortical and basal ganglial involvement in the initial phase, and generalized cerebral atrophy in the subsequent scan four and a half years later. The patient recovered from subacute measles encephalitis with substantial neurological deficits with the cessation of maintenance chemotherapy without specific antiviral treatment. This suggested that reconstitution of host immunity was adequate in effecting the clearance of the virus, and supporting the hypothesis that subacute measles encephalitis is primarily an opportunistic infection.