Symptomatic arachnoid cyst at the clivus drained stereotactically through the vertex.

A 40-year-old man had an acute ischemic event affecting the pons. He had no cardiac illness or vasculities and was not diabetic or hypertensive. The contrast-enhanced computed tomographic scan disclosed nothing abnormal, and a vertebral angiogram showed an avascular mass markedly displacing the basilar artery and pons posteriorly and toward the right. A magnetic resonance image clearly delineated a homogeneous arachnoid cyst containing cerebrospinal fluid. To avoid manipulating posterior fossa arteries, after the recent pontine stroke, this arachnoid cyst with unusually favorable anatomical landmarks was approached stereotactically through the vertex. Fenestration and drainage of the cyst was accomplished under local anesthesia and benzodiazepine sedation with low morbidity. The procedure was well tolerated, and the patient returned to gainful employment shortly afterward. He remains asymptomatic at 3 years' follow-up. The successful outcome of this case suggests that in carefully selected symptomatic arachnoid cysts, stereotactic interventions could become a useful surgical alternative. Stereotaxis may also be helpful in other cumbersome surgical cases in which a second port for contrast injection or simple manipulation would be advantageous.

Falling and postural deficits due to acute unilateral basal ganglia lesions.

Nine patients presented with sudden falling events to one side while sitting, standing, or walking. All were initially unaware of their severe postural deficit, and five were obfuscated. The observed falls were a distinctly slow, tilting motion in a stereotypic lateral or diagonal trajectory, literally "like a falling log." The events occurred with eyes opened and were exacerbated with eye closure, but no patient had evidence of cerebellar, vestibular, or posterior column dysfunction or significant motor weakness. Unilateral basal ganglia hemorrhages or lacunar infarcts contralateral to the side of the fall were demonstrated by computed tomographic scans. The overall prognosis was favorable; eight of nine patients regained independent ambulation within 3 to 6 weeks. Our findings indicate that a distinct loss of postural balance arises contralaterally to unilateral pallidal-putaminal lesions.

The effect of sucralfate on the steady-state serum concentrations of phenytoin.

The effect of sucralfate on steady-state phenytoin concentrations was evaluated in 6 normal volunteers. The subjects took phenytoin at bedtime until steady-state was confirmed (8 to 9 days) and then took in addition sucralfate 1g four times daily for a further 7 days. Serum phenytoin concentrations were measured on days 1, 3, and 7 of sucralfate administration. Measured phenytoin concentrations were 10.9 +/- 3.0 mcg/ml and 11.0 +/- 3.1 mcg/ml before sucralfate and 10.8 +/- 3.1 mcg/ml, 11.4 +/- 3.2 mcg/ml, and 11.1 +/- 2.5 mcg/ml during sucralfate administration (p greater than 0.05; ANOVA). These results suggest there is not a significant drug interaction between sucralfate and phenytoin.

Reversible optic neuritis secondary to paranasal sinusitis.

Three patients are described in whom optic neuritis was presumably caused by concurrent sinus infection. Aggressive treatment of the underlying sinus condition led to prompt visual improvement. Although underrecognized in clinical neurology, paranasal sinusitis is an uncommon but treatable cause of optic neuritis. Shortcomings of conventional radiological investigations and inappropriate use of corticosteroids may contribute to initial misdiagnosis.

Chemotherapy for bacterial infections of the central nervous system.

Over the past six years, many new agents have become available for the treatment of bacterial central nervous system (CNS) infections. Certain principles guide the use of these agents for CNS infections: first, an antimicrobial agent must be able to penetrate the CNS to be effective; second, the CNS is a "relatively immunoincompetent site" so that an antimicrobial must achieve levels within the CNS capable of killing the offending bacterium. The lack of efficacy of chloramphenicol for meningitis due to gram-negative aerobes is probably due to its failure to achieve such killing levels, whereas the success of the newer cephalosporins, such as cefotaxime and ceftriaxone, is due to their very high killing activity against these organisms. Penicillin remains the first choice for pneumococcal and meningococcal meningitis. Ampicillin plus chloramphenicol is still recommended as initial therapy for meningitis due to Hemophilus influenzae. The newer cephalosporins are now the first choice for the treatment of meningitis due to many gram-negative bacilli. Trimethoprim-sulfamethoxazole may also be useful in some of these infections and those due to Listeria monocytogenes. In the treatment of severe CNS infections, a team approach is advised to ensure optimal therapy.

Survival improvement in coccidioidal meningitis by high-dose intrathecal amphotericin B.

Eleven patients with coccidioidal meningitis were treated with high individual doses (1.0 to 1.5 mg) of intrathecal amphotericin B mixed with 25 to 50 mg of hydrocortisone in an attempt to reach a dose of 12 mg per month for at least two consecutive months. Patients received a mean intrathecal dose of amphotericin B of 82 mg (range, 40 to 157 mg) and 2.4 g intravenously (range, 1.0 to 3.5 g). No deaths related to disease or treatment occurred, and overall survival was 91% during an average follow-up period of 75 months (range, 30 to 137 months). Comparative analysis with eight well-known series in the literature reveals that our survival rate and follow-up time are significantly greater than the more recent series (1977-1981). Rank correlation and linear regression showed that the mean intrathecal dose of amphotericin B used in all series corresponds well with mean survival time. Our clinical results and analysis of the literature suggest that intrathecal amphotericin B administered at a high dose rate of 0.75 mg (or greater) three times per week promptly reaching 20 mg and a total surpassing 40 mg is associated with significantly enhanced survival rates.

Pontine hemorrhage causing Fisher one-and-a-half syndrome with facial paralysis.

The case of a 58-year-old white man with a history of high blood pressure and chronic obstructive pulmonary disease who developed double vision followed by right-sided facial paralysis is reported. A computerized axial tomogram (CT) scan showed an enhancing lesion in the pontine tegmentum, and the diagnoses of pontine glioma or hemorrhage were considered. Physical findings were limited to the cranial nerves. Conservative management with Decadron for 3 weeks resulted in a prompt clinical improvement, and a CT scan 1 month later showed resolution of the lesion, effectively ruling out a glioma. Total clinical recovery occurred at the end of 6 months. To our knowledge this is the first report of a case of Fisher one-and-a-half syndrome with facial paralysis correlated with computed tomography.

Lower cranial nerve palsies due to Pseudomonas osteomyelitis of the skull base.

A patient with pseudomonas osteomyelitis of the base of the left posterior fossa is reported. His clinical course was one of progressive paresis of the left 8th, 10th, and 11th cranial nerves. There have been three prior reports of osteomyelitis of the base of the skull not in contiguity with an infected paranasal sinus. Our patient subsequently developed osteomyelitis in the 3rd to 5th cervical vertebrae.

Fatal meningitis secondary to undetected bacterial psoas abscess. Report of three cases.

Three unusual cases of fatal meningitis secondary to undetected bacterial psoas abscess occurred at this institution over an 11-year period. All three patients had suffered chronic debilitating disorders before the abscess formation. The superimposed variable clinical presentations led to the initial diagnosis of a progressing cerebrovascular accident in one case, herniated nucleus pulposus at the L3-4 level in another, and osteomyelitis of the hip joint in the third. Analysis of these cases revealed that before the meningeal dissemination, all of the patients had shown evidence of intraabdominal pathology with positive psoas signs. Diagnostic and therapeutic guidelines are discussed.

Hypoliquorreic headache and pneumocephalus caused by thoraco-subarachnoid fistula.

One month after having a right upper lobectomy to remove a squamous cell carcinoma, a 43-year-old man presented with a 4-day history of postural headache, worsened by standing and relieved by lying. Skull films showed prominent ventricular pneumocephalus. Iophendylate myelography was unrewarding, but isotope cisternography revealed a CSF fistula at the T4 level, extending into the thoracic cavity. Thoracoplastic removal of the first four ribs successfully prevented air passage and the patient had a rapid uneventful recovery.

Physiopathogenesis of subdural hematomas. Part 1: Histological and biochemical comparisons of subcutaneous hematoma in rats with subdural hematoma in man.

The dorsal subcutaneous injection in rats of 12 ml or more of autologous hemolyzed whole blood clotted in situ induced the formation of sterile, hemispheric lesions, 47% of which showed an initial decrease in volume followed by a progressive enlargement. The behavior, histology, and biochemical characteristics of the liquid contents of these lesions were found to be remarkably similar to those of subdural hematomas in man. To evaluate the role of the various blood components that may have influenced the formation and growth of these lesions, more than 150 clots composed of human platelet-free plasma, autologous hemolyzed blood, or autologous whole blood were implanted subcutaneously in rats by either surgical or injection techniques. The in vitro behavior of the different clots used was also assessed. This systematic approach led to the following conclusions: 1) the composition and volumes of the clots are critical variables; 2) plasma-fibrin provides the matrix shape of the lesions; 3) the breakdown products derived from erythrocytes, hemoglobin, leukocytes, and other solid blood elements induce neomembrane formation and contribute to the lesion's subsequent growth; and 4) inflammation mechanisms appear to be essential, while cerebrospinal fluid plays no discernable role in this process.

Physiopathogenesis of subdural hematomas. Part 2: Inhibition of growth of experimental hematomas with dexamethasone.

A previously described experimental hematoma model, achieved by the subcutaneous injection of 12 ml of autologous hemolyzed blood clotted in situ, was made in 33 rats. Sventeen animals served as controls; the other 16 received daily intra-muscular injections of dexamethasone. After an initial decrease in size, 47% of the lesions in the control animals enlarged to a mean weight of 12.1 +/- 2.5 gm, while the lesions in the 16 steroid-treated rats weighted 3.2 +/- 0.70 gm (p less than 0.01). Histologically, lesions from the steroid group showed absence of neomembrane formation. These data offer further support to the theory that the neomembrane development and subsequent enlargement of subdural hematomas is due to inflammatory reactions of tissues in contact with large blood clots.

Reversal of dementia in normotensive hydrocephalus after removal of a cauda equina tumor. Case report.

An elderly man presented with signs of normotensive hydrocephalus. Elevated protein content in the spinal fluid led to the diagnosis of an "asymptomatic" cauda equine neurilemoma and its removal. Within 6 weeks the patient's mental status had dramatically improved. Chronic transudation of plasma proteins including fibrinogen into the subarachnoid space had probably impeded spinal fluid reabsorption. It is suggested that the leakage of fibrinogen into the cerebrospinal fluid may be the cause of hydrocephalus in other clinical settings in which there is an elevation of the spinal fluid protein.

Abnormal lumbar isotope cisternography in an unusual case of spontaneous hypoliquorrheic headache.

The unusual case of spontaneous hypoliquorrheic headache reported here was clinically identical to that originally described by Schaltenbrand. This is the first case to be studied by radioisotope cisternography, which showed that the cerebrospinal fluid flow was essentially normal. However, the radioactivity counts percent decreased rapidly, with simultaneous appearance of high isotope concentration in the urinary bladder. Scan images did not show cerebrospinal fluid (CSF) leakage at the puncture sites. Our data suggest that this postural headache syndrome is not caused by decreased CSF production, but by a very rapid absorption or unusual CSF leakage.

Local alterations of hemostatic-fibrinolytic mechanisms in reforming subdural hematomas.

Multiple chemical and coagulation determinations were undertaken on the subdural hematoma fluid from the reformed effusions of two patients. It was found that plasma or blood repeatedly reentered the subdural cavity. Coagulation studies compared the in vitro effects of subdural fluid with those of cerebrospinal fluid, serum, and a buffer control. Despite some chemical differences, the subdural fluids from both patients behaved similarly by (1) accelerating the intrinsic clotting system, (2) producing defective clot formation, and (3) accelerating the fibrinolytic system. It is presumed that these continuous hemostatic-fibrinolytic alterations, acting in the subdural sac, may have important implications in the growth and reformation of subdural hematomas, and a hypothesis of the mechanisms involved is presented.