Extradural hemorrhage on the flight line: case report.

Epidural hematoma formation may be expected to occur in 3% of head injuries. The unique pathophysiology of this lesion may complicate early diagnosis, resulting in significant morbidity and mortality if definitive surgical intervention is delayed. Personnel required to work at significant heights servicing large cargo aircraft are certainly at risk for this type of trauma. A case is presented of a traumatic extradural hematoma in a ground aircraft crewman with successful neurosurgical treatment, along with a discussion of the salient features of this potentially lethal traumatic neuropathology.

Chronic subdural haematoma, an unusual injury from playing basketball.

Although the literature records instances of acute epidural haematoma and acute subdural haematoma related to playing basketball, there has not been a report of chronic subdural haematoma as a basketball injury. With the burgeoning interest in this sport in the United Kingdom and Europe, the possibility of this particular neurotrauma increases. Such an injury, along with the diagnosis and management of this often insidious lesion, is documented in this case report.

The beginnings of neurosurgery in California during the pre-Cushing era: 1850-1900.

The end of the present millennium marks the centennial of Harvey Cushing's European study year, after the completion of his surgical residency under William Stewart Halsted at the Johns Hopkins Hospital and just before beginning his surgical practice in Baltimore, Maryland. The year 2000 marks the sesquicentennial of California's admission to the Union as the 31st state. This report documents a number of the events and achievements that occurred during this "pre-Cushing era" (1850-1900) that contributed to the ultimate development of neurological surgery in California. The historical milestones of the California gold rush, the completion of the Transcontinental Railroad across the Sierra Nevada Mountains, and the careers of early California physicians and educators, including those of Hugh Toland and Levi Cooper Lane, were instrumental in building a foundation for the modern discipline of neurosurgery in the Golden State. This foundation would serve as a cornerstone for surgeons trained by Harvey Cushing (including Howard Naffziger, Carl Rand, and Edward Towne) who would arrive in California early in the 20th century and would define the specialty of neurosurgery. The legacy left by these physicians enhances the celebration of the closure of the millennium.

Stereotactically guided thalamotomy for treatment of parkinsonian tremor isolated to the lower extremity. Case report.

The authors present a case of tremor isolated to the lower extremity that was treated with stereotactically guided thalamotomy in a patient with Parkinson's disease. The technology that makes this procedure effective for this particular manifestation of parkinsonism is discussed.

Public health on the railroad: William Freeman Snow and the California Sanitation Exhibit.

This paper describes the California Sanitation Exhibit, a railroad car outfitted for instruction in public health that toured California in 1909 and 1910. The sanitation exhibit used display models, photographs, and lectures to educate the public about tuberculosis and other infectious diseases, waste contamination, and the dangers of bad milk. The success of the exhibit, which reached 5% of the state's population, resulted in the appointment of its creator, William Freeman Snow, as secretary of the California State Board of Health.

A roentgen centennial legacy: the first use of the X-ray by the U.S. military in the Spanish-American War.

The year 1996 marked the centennial of the advent of the roentgen ray in the United States. The compelling value of this novel scientific discovery by Professor Wilhelm Roentgen of Würzberg, Germany, to image the previously arcane depths of the living human body was astounding and recognized as a major advance. This report details the work of some key personnel and developments in the science of warfare that confirmed the great promise of the X-ray in the diagnostic armamentarium of military surgeons (a leading proponent being Professor Nicholas Senn, the founder of the Association of Military Surgeons of the United States) in this last American conflict of the 19th century.

Treatment of progressive cervical spinal instability secondary to hydatid disease. A case report.

STUDY DESIGN: A case report of a patient with progressive cervical spinal instability secondary to hydatid disease and the operative therapy. OBJECTIVE: To document how the combination of contemporary imaging, medical, and operative methods has obviated severe neurologic sequelae in a patient's cervical spine ravaged by hydatidosis. SUMMARY OF BACKGROUND DATA: The incidence of hydatid disease in the vertebral column is unusual and rare in the cervical spine. Until recently, patients with spinal hydatid disease have had guarded prognoses, because the various medical and surgical therapies could not effect curative or even palliative results. METHODS: The use of contemporary imaging methods, including computed tomography and magnetic resonance imaging, is described, in conjunction with current anthelminthic therapy and operative spinal instrumentation in this patient with recurrent quadriparesis from progressive hydatid spinal erosion. RESULTS: With the operative and medical therapies described in this case report, the patient has had six successful operative results in 6 years for cervical spinal hydatidosis and remains neurologically normal, with a stable cervical spine. CONCLUSIONS: It is hoped that this case presentation will justify a spirit of guarded optimism in the patient whose spine has been rendered unstable by hydatid disease and that, though a cure is still not likely, at least the past inexorable prognosis of paralysis and death is ameliorated.

Spontaneous acute subdural hematoma precipitated by cocaine abuse: case report.

A novel complication of the illicit use of cocaine, a spontaneous acute subdural hematoma, is described. This case represents another addition to the growing literature on the negative effects of cocaine on the central nervous system. Photographic documentation of the lesion responsible for the hematoma is presented, along with a discussion of the possible pathophysiologic mechanism.

Pontine-crossed paralysis consequent to multiple trauma: case report.

The case of a multiple trauma victim with a brain-stem injury, resulting in a syndrome of pontine-crossed paralysis, is presented. Demonstration of these disorders in the setting of multiple trauma is highly unusual, but the diagnosis is established quickly and accurately through magnetic resonance imaging. A possible mechanism of injury is presented for discussion.

Sir William Macewen's visit to California as the First Lane Medical Lecturer. A centennial celebration.

1996 marked the centennial anniversary of the 1896 visit to California of William Macewen, MD, Regius Professor of Surgery of the University of Glasgow, Scotland, to give the first Lane Medical Lectures. I describe the origins of this historic lecture series and include photographic records. The progress and development of modern California medicine have been greatly influenced by the personalities who initiated and nurtured this lecture series.

Characterization of a large conductance non-selective anion channel in B lymphocytes.

Studies on ion channel currents in freshly isolated murine B lymphocytes with the patch clamp technique revealed the presence of a non-selective anion channel of large conductance in inside-out (i/o) patches. This channel is characterized here according to its unitary conductance, ion selectivity, regulatory factors, distribution and kinetic behaviour. With a unitary conductance of 348 +/- 4.4 pS in a normal physiological ion gradient, it exhibited an indiscriminate selectivity to cations (Na+ and K+). Selectivity to chloride over sodium was established by substitution of high concentrations of NaCl (450 mM) in the bath (i/o patches), resulting in a selectivity ratio (PCl/PNa) of 33. Selectivity to chloride over potassium was confirmed in a similar manner by substitution of TEA-Cl for KCl, yielding a selectivity ratio (PCl/Pk) greater than 80. Conductance of aspartate through the channel demonstrated the non-selective nature of this anion channel. Voltage proved to be a regulatory factor but other influences on channel activity were also present, including the configuration of the patch (channel is inactive in cell attached patches), and the enhancement of activity at negative membrane voltages by previous pulsing. Intracellular levels of calcium (i/o patches) did not appear to control channel conductances or regulate kinetic activity. Kinetic behaviour of this channel was complex, with periods of bursting and flickering activity interspersed with prolonged closed/open intervals. Multiple subconductance states were also present. The complex properties and behaviour of this channel suggest a possible role in signal transduction in B cell activation.

Amiloride-sensitive cation channel in apical membrane of inner medullary collecting duct.

Ion channels in the apical membrane of rat inner medullary collecting duct (IMCD) cells in primary culture were studied with the patch-clamp technique. A 27.5 +/- 1.2 pS non-selective cation channel was characterized in inside-out patches. The channel did not discriminate between Na+ and K+ (n = 8) and had a Na permeability-to-Cl permeability (PNa:PCl) ratio of 13:1 (n = 3). Amiloride (5 x 10(-7) M, n = 5) on the extracellular side of the membrane inhibited channel activity 10-fold at negative membrane voltages (voltage refers to cell interior with respect to patch pipette). This diuretic decreased the mean open time and increased the mean closed time without altering single-channel conductance. Voltage-dependent inhibition of this channel by amiloride distinguishes its behavior from other known nonselective cation channels. Neither voltage, Ba2+ (1 mM), tetraethylammonium (5 mM) nor changes in the bath pH (6.1 to 8.0) altered channel activity. Although the channels were active in 41% of the patches in the inside-out configuration, with a percent open time lying between 35 and 60 (-70 to +60 mV), channels were only active in 9% of the cell-attached patches. In preliminary microelectrode studies we have observed an amiloride-inhibited conductance in the apical membrane of isolated and perfused rat IMCD. Therefore, this novel nonselective cation channel identified in IMCD cells in culture may represent the amiloride-sensitive conductance observed in isolated and perfused IMCD and may mediate electrogenic Na+ absorption.

A computer method for the acquisition and analysis of patch-clamp single-channel currents.

The method we present instructs the computer to deliver sets of programmed membrane voltages and allows the acquisition of large amounts of digitized data, compact storage, ready identification of records and rapid, interactive analysis of channel current data. A typical cycle of analysis including amplitude determination and kinetic measurements for 10 s of continuous data digitized at 5 kHz requires 5-20 min depending on the complexity of the observed channel activity. This procedure is compatible with such storage protocols as that described by Bezanilla [Biophys. J., 47 (1985) 437-441], although there are obvious benefits to using standard computer storage devices such as hard disks, floppy disks, and Bernoulli Boxes. The programs described in this report are available from the authors.

Ion channels in human macrophages compared with the U-937 cell line.

The human cell line U-937 has been used extensively to model many macrophage functions. We have examined the cell membranes of human monocyte-derived macrophages (HMDM) and U-937 cells to compare membrane properties as expressed by single ion channel currents. The patch-clamp technique was applied to isolated, nonactivated, inside-out patches of cell membranes obtained from HMDM and from the U-937 cell line. Voltage-gated potassium channels of similar conductance but different kinetics are present in both types of cells, and a calcium-activated potassium channel is present only in the HMDM. These differences in ion channel properties suggest fundamentally different behavior between these two cell types at the level of the cell membrane.

Apoplexy in a prolactin microadenoma leading to remission of galactorrhea and amenorrhea.

A 28-year-old woman with bilateral headaches and vomiting was found to have normal prolactin levels despite an eight-year history of intermittent galactorrhea and amenorrhea and the current finding of a pituitary microadenoma. The microadenoma contained hemosiderin. It is concluded that pituitary apoplexy is not confined to large tumors that have outgrown their blood supply, but can occur in microadenomas with regression of a positive endocrinopathy.

Persistent isodense intraventricular hematoma caused by intraventricular saccular aneurysm.

A case of intraventricular hemorrhage secondary to an intraventricular saccular aneurysm is presented in which the hematoma mass gave a false appearance of resolution secondary to its progressive isodense appearance on serial computerized cranial tomograms. Intraventricular saccular aneurysms are unusual lesions and a most uncommon cause of intraventricular hemorrhage. Diagnosis of intraventricular hemorrhage has been greatly facilitated since the advent of cranial computerized tomography though elucidation of the definitive cause of hemorrhage in this case still depended upon cerebral angiography. In addition, the development of isodensity by the hematoma mass on serial computed tomograms has led to this case report.