Is Mediastinoscopy Necessary in the Evaluation of Lung Cancer?

The records of 96 consecutive patients who underwent mediastinoscopy and were ultimately shown to have bronchogenic carcinoma were reviewed. Indirect tests for mediastinal tumor metastases in these patients included bronchoscopy and chest roentgenograms in all 96, mediastinal laminagrams in 65, esophagograms in 27, carinal biopsy in 23, bronchograms in 5, pulmonary angiograms in 5, azygograms in 2, and aortograms in 2 patients. Of the 43 patients in this series in whom all indirect tests revealed no metastases, mediastinoscopy showed nodal involvement in 11 (28%), who were thus spared unnecessary thoracotomy. On the other hand, if negative mediastinoscopy had not cast doubt on the validity of indirect tests that seemed to show metastases, an operation might actuallly have been denied to 14 patients who were ultimately proved to have anatomically resectable disease.     

Cervical nystagmus due to loss of cerebellar inhibition on the cervico-ocular reflex: a case report.

Studies of the cervico-ocular reflex and the vestibulo-ocular reflex have been carried out separately and in combination on a patient with gait ataxia due to a cerebellar tumour. With the head fixed in space, body rotation to the right (left neck torsion) induced marked nystagmus to the left in darkness. Vestibulo-ocular responses to sinusoidal rotation were symmetrical while the neck was immobilised and asymmetric when it moved freely. It is suggested that the cervical nystagmus seen in this case was the result of removal of cerebellar inhibition upon the cervico-ocular reflex and that abnormal interaction of cervical and vestibular inputs could have played a role in the patient's unsteadiness.     

Testing the vestibular-ocular reflexes: abnormalities of the otolith contribution in patients with neuro-otological disease.

Conventional vestibular rotation testing with the head centered on the axis stimulates the semicircular canals evoking compensatory eye movements. If the head is placed forwards of the axis in an eccentric position the otoliths are also stimulated by a tangential linear acceleration acting laterally to the skull. In normal subjects the additional otolithic stimulus evokes compensatory eye movements with a higher gain than with head centred, particularly for high frequency (greater than 0.1 Hz) stimuli. The responses with head centred and eccentric in various patients with known/suspected neuro-otological abnormalities have been compared. Patients with vestibular neurinectomies who have asymmetrical head centred responses showed greater asymmetry with head eccentric at higher stimulus frequencies. Some patients with cerebellar lesions showed abnormally enhanced or depressed and asymmetrical responses with head eccentric in comparison with head centred responses, which could be normal. The enhancing effects could be specific to low frequency stimuli. All patients who showed abnormal responses with head eccentric also had positional nystagmus provoked by the gravity acceleration vector when the head was tilted laterally. The direction of the positional nystagmus with respect to the gravity vector was not necessarily the same as the direction of the effect on eye movements of lateral acceleration during eccentric oscillation. Patients with benign paroxysmal vertigo or chronic linear vertigo in whom otolithic abnormalities are suspected were not found to have abnormal responses with head eccentric. We conclude that this method of testing may be useful in elucidating pathophysiology but is not a decisive clinical test for the presence of disordered otolith function.     

Staged bilateral pallidotomy for treatment of Parkinson disease

OBJECT: Several investigators have described the motor benefits derived from performing unilateral stereotactic pallidotomy for the treatment of Parkinson disease (PD), but little is known about the efficacy and complication rates of bilateral procedures. The goal of this study was to assess both these factors in 12 patients. METHODS: Eleven patients with medically intractable PD underwent staged bilateral pallidotomy and one patient underwent a simultaneous bilateral procedure. Unilateral pallidotomy resulted in an improvement in the patients' Unified Parkinson Disease Rating Scale (UPDRS) total scores and motor subscores, Hoehn and Yahr stages, and Schwab and England Activities of Daily Living scores. There were no complications. The second procedures were performed 5 to 25 months after the first, and nearly complete 3-month follow-up data are available for eight of these patients. Staged bilateral pallidotomy did result in further improvements in some symptoms, but the patients proved to be less responsive to levodopa. In contrast to outcomes of the initial unilateral pallidotomy, there were significant complications. One patient suffered an acute stroke, two patients suffered delayed infarctions of the internal capsule, four patients had mild-to-moderate worsening of speech and increased drooling, and one patient complained of worsening memory. CONCLUSIONS: Bilateral pallidotomy results in modest benefits but is associated with an increased risk of complications.     

Involvement of OSP/claudin-11 in oligodendrocyte membrane interactions: role in biology and disease

Oligodendrocyte-specific protein (OSP/claudin-11) is a four transmembrane protein concentrated in central nervous system myelin. Recent evidence has emerged suggesting that OSP/claudin-11 is involved in membrane interactions at tight junctions and with the extracellular matrix. OSP/claudin-11 seems to modulate proliferation and migration of oligodendrocytes presumably through these interactions. Furthermore, evidence is presented implicating OSP/claudin-11 as an autoantigen in the development of autoimmune demyelinating disease.