To determine the frequency of early computed tomographic (CT) findings of ischemia and their relationship to symptom duration and neurologic dysfunction within 3 hours of ischemic stroke.

The CT scans of 39 acute stroke patients were evaluated for signs of early ischemic change within 3 hours of symptom onset and without knowledge of the patient’s neurologic deficit or results of a 24 hour follow-up post-thrombolysis CT. Early CT signs of acute ischemic change or thromboembolism were hypoattenuation of the insular ribbon, obscuration of the lentiform nucleus, cortical hypodensity/effacement, and hyperdense middle cerebral artery sign.

Signs of acute ischemic change were seen on the baseline scan in 25/39 patients (64%). Hypoattenuation of the insular ribbon was seen in 11 patients, obscuration of the lentiform nucleus in 13, cortical hypodensity/effacement in 13, and hyperdense middle cerebral artery sign in 7. The prevalence of early ischemic signs was directly associated with increasing neurologic disability at the time of presentation. No clear relationship existed between symptom duration and the presence of CT signs.

Evidence of cerebral ischemia is frequently seen on CT within 3 hours of symptom onset. The degree of neurologic disability correlates with CT signs of ischemia.

We report an unusual case of the CT appearance of diffuse subarachnoid hemorrhage in a patient with anoxic encephalopathy, a situation which neurosurgeons, neurologists, and neuroradiologists should be aware of.

A young man collapsed unconscious in jail after abusing an unknown quantity and variety of drugs. CT scan showed a picture compatible with diffuse subarachnoid hemorrhage.

As the patient had a Glasgow Coma Score of 3 no heroic intervention was undertaken. An autopsy performed 40 hours after the initial ictus and 24 hours after death revealed no evidence of subarachnoid hemorrhage but gross and microscopic evidence of anoxic encephalopathy.

Anoxic encephalopathy can mimic diffuse subarachnoid hemorrhage on CT.

To review the clinical characteristics and associated features found in patients with psychogenic tremor.

Ten-year retrospective review of charts of all patients and videotapes of fifty-one patients diagnosed by the senior author as having psychogenic tremor.

Seventy patients fulfilled the diagnostic criteria for clinically definite psychogenic tremors. Psychogenic tremors usually started abruptly (73%), often with the maximal disability at onset (46%), and then took static (46%) or fluctuating (17%) courses. Psychogenic tremors usually started in one limb and spread rapidly to a generalized or mixed distribution. Spontaneous resolution and recurrence, easy distractibility together with entrainment and response to suggestion were characteristic features. Presence of functional symptoms and signs and refractoriness to conventional antitremor drugs were common.

Psychogenic tremor is generally not a diagnosis of exclusion. The presence of characteristic features on history and especially clinical examination can permit an accurate diagnosis and avoid unnecessary investigations.

This study demonstrates the utility of a newly-developed moveable 1.5 Tesla intraoperative MR imaging system using a case report of a multi-lobulated parafalx meningioma.

A 43-year-old female presented with progression of a multi-lobulated anterior parafalx meningioma several years following resection of a large left frontal convexity meningioma.

Surgical excision of the lesion was undertaken. Following apparent total resection, intraoperative MR imaging revealed two residual dumbell shaped lobules. Using these updated MR images, the tumour was readily identified and removed.

The moveable 1.5 Tesla intraoperative MR system used in the present case provides rapid, high resolution MR images during neurosurgical procedures. Moving the magnet out of the surgical field during surgery permits the use of all standard neurosurgical instruments. The ease of use and quality of images combined with minimal interference on well-established surgical techniques makes this system a valuable adjunct in the neurosurgical treatment of intracranial disease.

Little is known about vitamin B12 deficiency myelopathy's magnetic resonance imaging (MRI) manifestations and their relationship to the onset, evolution, and resolution of neurologic signs and symptoms.

We present a case and review eleven additional reported cases of subacute combined degeneration of the spinal cord detected by MRI.

Our patient had increased T2-weighted signal and gadolinium contrast enhancement of the posterior columns in the cervical and thoracic regions and enhancement of the lateral columns in the high cervical region. This is a case with imaging evidence for lateral column lesions. Two prior reports have shown posterior column enhancement. T1-weighted images may show decreased signal in the posterior columns and sometimes demonstrate reversible spinal cord swelling. MRI abnormalities typically improve after vitamin replacement therapy. However, clinical signs may persist despite resolution of imaging abnormalities, and these abnormalities do not always resolve completely. In addition, symptoms may precede the imaging abnormality.

Vitamin B12 deficiency may produce an increased T2-weighted signal, decreased T1-weighted signal, and contrast enhancement of the posterior and lateral columns of the spinal cord, mainly of the cervical and upper thoracic segments. Because the symptoms may precede any imaging abnormality, it is clear that spinal cord MRI may not be a highly sensitive, early test for subacute combined degeneration.

The aim of the present study was to examine the frequency and the phenotypic manifestations in a French-Canadian population with a chromosome 17p11.2 duplication (Charcot-Marie-Tooth type 1A, CMT-1A).

Molecular analysis were performed by Southern blot using pVAW409R3a probe. Clinical evaluation was carried out according to the scale defined by the European HMSN Consortium.

The frequency of duplication was found to be similar in the adult (70.8%) and pediatric (72.7%) populations. Onset of symptoms occurred before 20 years of age in 85.7% of adult cases and before the age of 5 in 80% of the pediatric cases. The classical CMT syndrome was observed in 77% of the cases and the syndrome was associated with additional features in 15% of cases in the adult population. All the children presented with classical CMT syndrome with no additional features. There was a significant correlation between the disability score and the duration of the disease but no correlation was found between median nerve conduction velocity and the functional handicap, the age at onset or the duration of the disease. In one family, there was a very conspicuous anticipation over five observed generations.

This study reveals that the age at onset, the clinical and electrophysiological variability as well as the functional disability variations in a French-Canadian population did not differ from those reported in other populations.

Paraneoplastic encephalomyelitis (PEM) is a well characterized, and typically irreversible, paraneoplastic syndrome, usually associated with small cell lung cancer or other malignancy. We describe a case of a young woman with a benign ovarian teratoma who presented with a reversible PEM.

A 24-year-old woman presented with a three week history of memory impairment, unusual behavior, personality changes, auditory hallucinations, hypersomnolence and binocular diplopia. On admission she was disoriented and inattentive with impaired short term memory. Small doses of lorazepam (1 mg), given for episodic agitation, repeatedly induced multidirectional bilateral nystagmus and a skew deviation, but her neurological examination was otherwise normal. A left-sided pelvic mass was palpable. Brain MRI pre- and post-gadolinium was normal. There was a mild CSF pleocytosis and an EEG showed minimal bilateral background activity irregularities. There were no other laboratory abnormalities. Two weeks after admission, she clinically deteriorated developing central respiratory failure and a flaccid paraplegia. Repeat MRI showed an area of increased T2 weighted signal in the medulla and three similar areas in the spinal cord. Following removal of her tumor, treatment with high dose corticosteroids and intravenous immunoglobulin, she ultimately made a full recovery. Pathology revealed the tumor to be a benign ovarian cystic teratoma.

This is the first report of a reversible PEM seen in association with a benign tumor, in this case a mature ovarian teratoma. Presumably, an immune response directed against neural elements of the teratoma cross-reacted with normal brain, brainstem and spinal cord antigens to cause neurologic symptoms. Tumor removal was followed by neurologic recovery.

Cranial dermal sinuses are rare and occur most frequently in the posterior fossa and along the midline. Likewise, supratentorial dermoid cysts are very uncommon.

We report a unique case of an adult female patient with both a supratentorial dermoid cyst and an incomplete dermal sinus tract.

The patient is a 31-year-old female, who presented with a new onset complex partial seizure. Neuroimaging and surgery revealed a right superior temporal dermoid cyst with an associated dermal sinus tract. Furthermore, the dermal sinus tract was incomplete and had no cutaneous manifestations.

We present a rare patient with an off midline supratentorial dermoid cyst associated with a uniquely incomplete cranial dermal sinus tract. The dermal sinus tract involved the bone, dura and intradural compartment, without involving the overlying skin. This represents a novel variant in the spectrum of cranial dermal sinus abnormalities.

Diagnostic confusion between thyroid disease and myasthenia gravis (MG) can arise because the two may have similar clinical features, and also because of the more frequent coexistence of these autoimmune disorders in the same individual. In MG, autoantibodies directed against the acetylcholine receptor result in muscle weakness. Thymic pathology is well recognized in MG, with thymic hyperplasia frequent in early onset MG and thymoma more common in later onset MG. In Graves’ disease, autoantibodies against thyroid antigens result in hyperthyroidism. A seldom-recognized feature of Grave’s disease is the occurrence of an enlarged thymus (thymic hyperplasia) on chest CT, or of thymic lymphoid hyperplasia pathologically.

This report describes a case in which the discovery of a mediastinal mass during imaging of the thyroid, and the presence of myasthenic-like symptoms, in a patient with Graves’ disease prompted investigations into whether the patient also had MG.

Despite symptoms which strongly suggested MG, subsequent investigations did not confirm the diagnosis, and treatment of Grave’s lead to a resolution of the symptoms and regression of the thymic enlargement seen on CT.

The case study highlighted clinical similarities between Grave’s disease and myasthenia gravis which might cause diagnostic confusion, and also the investigations which are useful in order to differentiate the two diseases. In addition to common clinical features, the autoimmune diseases Grave’s disease and myasthenia gravis may both produce radiological thymic enlargement.

Quadriplegic myopathy (QM) and its variants generally are described in critically ill patients who are exposed to steroids and nondepolarizing muscle blocking agents (NDMBAs).

A patient with sepsis who was not exposed to steroids or an NDMBA infusion developed QM and was studied using serial quantitative electromyography.

Clinical and electrophysiological studies identified evidence of a severe myopathy and muscle biopsy showed necrosis, calcifications and selective loss of myosin filaments in non-necrotic fibers. Her clinical recovery paralleled rises in motor unit action potential (MUAP) amplitudes studied by serial automatic decomposition electromyography (ADEMG).

QM can develop with sepsis and without significant exposure to steroids and NDMBAs. ADEMG can be a useful tool in electrophysiological evaluation of critically ill patients with weakness.

Isolated trigeminal neuropathy is uncommon; causes include trauma, inflammation, or neoplasm.

We report a patient who fell and struck his head during a myocardial infarction, was treated with streptokinase, and developed symptoms and signs of an isolated trigeminal sensory neuropathy.

Imaging showed hemorrhage in the trigeminal nerve root; follow-up imaging showed resolution of the hemorrhage, but no underlying structural lesion.

A combination of head trauma plus thrombolysis resulted in an isolated trigeminal neuropathy.

Ganglioglioneurocytoma is not yet a well defined clinical and histopathological entity; recent reports outline the histopathological features of this very rare trimorphous tumor, under different names with its basic components of gangliocytoma, neurocytoma and glioma. Four previous reports described this tumor in eleven patients. This is the first case report describing ganglioglioneurocytoma in the posterior fossa.

A 31-year old male with midline posterior fossa ganglioglioneurocytoma is described, providing the neuroimages and histopathological studies.

Ganglioglioneurocytoma is a rare mixed neuronal and glial tumor that can also occur in the posterior fossa.