The utility of transoesophageal echocardiography to determine management in suspected embolic stroke.

BACKGROUND: Assessment for source of stroke is a common indication for transoesophageal echocardiography (TOE). Although an abnormality is frequently found, it remains uncertain how frequently the findings alter patient management. Also, the role of transthoracic echocardiography (TTE) prior to or instead of TOE is not well defined. We sought to determine the use of TTE prior to TOE, the outcome of the TOE and its impact on management. METHODS: We retrospectively reviewed the records and echocardiography results of 100 consecutive patients who underwent TOE for any reason at a tertiary hospital. In 35 subjects (35%), the indication was evaluation for source of stroke. Among these, we determined clinical risk factors for stroke, if a TTE was performed prior to their TOE, the results of the TOE and its effect on management. RESULTS: The mean age of the stroke patients was 64.6 years (17-90) and 49% were women. Eighty per cent had at least one risk factor for stroke and 17% had atrial fibrillation. A TTE, performed in 40% prior to the TOE, found an abnormality in 14% (2/14). The TOE showed an abnormality in 71% of patients; 54% had aortic atheroma; 17% PFO; 14% spontaneous echo contrast; 6% left atrial appendage thrombus, 3% left ventricular thrombus and 3% vegetation. In only one patient (3%) the management was altered based on the abnormal TOE findings. CONCLUSION: An abnormality on TOE, although common (71%) and more sensitive than TTE, altered management in only 3% of subjects referred for stroke assessment. Its role requires further consideration.

Perineural spread of facial squamous cell carcinoma.

A 64 year old man presented with progressive impairment of right sided cranial nerves. Chronic immunosuppression for renal transplantation had resulted in multiple squamous cell carcinomata of the head and neck. Magnetic resonance imaging and subsequent right facial nerve biopsy confirmed perineural spread of a squamous cell carcinoma as the cause of the multiple cranial neuropathies.

Intra-arterial thrombolysis in acute ischaemic stroke.

Several thrombolytic agents for the treatment of acute ischaemic stroke have been examined; however, to date, only the i.v. administration of recombinant tissue plasminogen activator is licensed in Australia. Although no trials directly comparing intra-arterial and i.v. delivery of thrombolytics exist, intra-arterial thrombolysis has several potential advantages, including angiographic assessment of the thrombus and the site of occlusion and collateral circulation, improved recanalization, and delivery of higher local concentrations of thrombolytic agents and extending the therapeutic time window for treatment. We conducted a retrospective audit of our experience with the use of intra-arterial urokinase to treat acute ischaemic stroke at an Australian tertiary-care hospital between June 1993 and June 2003. We examined time from stroke onset to assessment, computerized tomography scan, cerebral angiography and thrombolysis, anatomical classification of intra-arterial thrombus, rates of symptomatic intracerebral haemorrhage, and clinical outcome at 3 months. We believe that in carefully selected individuals in appropriate centres of expertise, intra-arterial thrombolytic therapy holds great promise.

Recurrent Miller-Fisher syndrome.

A case of recurrent Miller-Fisher syndrome is presented and features of this very rare condition are discussed.

Progressive supranuclear palsy pathology caused by a novel silent mutation in exon 10 of the tau gene: expansion of the disease phenotype caused by tau gene mutations.

Genetic mutations in the tau gene on chromosome 17 are known to cause frontotemporal dementias. We have identified a novel silent mutation (S305S) in the tau gene in a subject without significant atrophy or cellular degeneration of the frontal and temporal cortices. Rather the cellular pathology was characteristic of progressive supranuclear palsy, with neurofibrillary tangles concentrating within the subcortical regions of the basal ganglia. Two affected family members presented with symptoms of dementia and later developed neurological deficits including abnormality of vertical gaze and extrapyramidal signs. The third presented with dystonia of the left arm and dysarthria, and later developed a supranuclear gaze palsy and falls. The mutation is located in exon 10 of the tau gene and forms part of a stem-loop structure at the 5' splice donor site. Although the mutation does not give rise to an amino acid change in the tau protein, functional exon-trapping experiments show that it results in a significant 4.8-fold increase in the splicing of exon 10, resulting in the presence of tau containing four microtubule-binding repeats. This study provides direct molecular evidence for a functional mutation that causes progressive supranuclear palsy pathology and demonstrates that mutations in the tau gene are pleiotropic.

Herpes zoster arteritis. Clinical and angiographic features.

Herpes zoster ophthalmicus is a common condition, and has now been widely recognised as associated with the delayed onset of neurological events, associated with angiographic evidence of arteritis. The time lag between the zoster and subsequent neurological symptoms, along with the age of the patients, often leads to a missed diagnosis. As more cases are recognised, the pathogenic mechanisms will be better characterised and treatment may become more effective.

A survey of the pattern reversal visual evoked response (PRVER) in 1428 consecutive patients referred to a clinical neurophysiology department.

The records of 1428 neurological patients referred to a department of Clinical Neurophysiology for PRVER testing have been reviewed. Half field studies with multichannel recordings were carried out in the majority. 1186 of these patients had a provisional diagnosis of MS; 42% had abnormal PRVERs compared with 25% for those patients who did not have MS. Symmetrical latency increases from stimulation of either eye, interocular latency abnormalities and amplitude abnormalities were as frequent in the non-MS patients as the group with a provisional diagnosis of MS. A small proportion of patients had neurophysiological evidence of field defects; homonymous hemianopias occurred as frequently as "central" defects in the MS group. The PRVER abnormalities are considered in relation to the current models of conduction in demyelinated fibres.

Syndrome of ophthalmoplegia, ataxia and areflexia.

The clinical details and results of some laboratory investigations are described in 4 patients who initially presented with severe external ophthalmoplegia, ataxia and areflexia. In 3 of these patients paresis of the limbs was restricted and minimal as in the syndrome first described by Fisher (1956). The fourth patient initially presented with similar symptoms but his illness progressed to a more typical form of acute idiopathic polyneuropathy, confirming Fisher's (1956) contention that this syndrome is an unusual variant of acute idiopathic polyneuritis.