Intracranial cerebrospinal fluid measurement studies in suspected idiopathic normal pressure hydrocephalus, secondary normal pressure hydrocephalus, and brain atrophy.

OBJECTIVE: To investigate intracranial cerebrospinal fluid (CSF) distribution in patients with a clinical diagnosis of idiopathic normal pressure hydrocephalus (INPH). METHODS: 24 patients with a clinical diagnosis of INPH were studied. Control groups comprised 17 patients with secondary normal pressure hydrocephalus (SNPH), 21 patients with brain atrophy, and 18 healthy volunteers. Ventricular volume (VV) and intracranial CSF volume (ICV) were measured using a magnetic resonance based method and the VV/ICV ratio was calculated. RESULTS: The SNPH group showed a marked increase in the VV/ICV ratio compared with the healthy volunteers (37.8% v 15.6%, p < 0.0001). The brain atrophy group showed a significant increase in ICV compared with the healthy volunteers (284.4 ml v 194.7 ml, p =0.0002). The INPH group showed an increase in ICV (281.2 ml, p = 0.0002) and an increase in the VV/ICV ratio (38.0%, p < 0.0001). Fifteen of 24 INPH patients underwent shunting; 11 improved and four did not. CONCLUSIONS: The results suggest that INPH patients have brain atrophy in addition to hydrocephalic features. This may help to explain the difficulties encountered in the diagnosis and the unpredictable response rate to shunt surgery in INPH patients.

Intracranial cerebrospinal fluid distribution and its postoperative changes in normal pressure hydrocephalus.

BACKGROUND: This study was conducted to investigate the usefulness of intracranial cerebrospinal fluid (CSF) volume measurement using MR-based methods in the management of patients with normal pressure hydrocephalus (NPH). METHODS: The study group comprised 19 patients with NPH who showed a favorable outcome after ventricular shunting, 15 normal volunteers (NV), and 15 patients with cerebrovascular disease (CVD). A 3D-fast asymmetric spin echo MR imaging sequence and the region-growing method were used to extract the CSF space from MR images. Ventricular volume (VV) and intracranial CSF volume (ICV) were measured and the VV/ICV ratio was calculated in each case. In NPH patients, the CSF volume was measured again after shunting. FINDINGS: The mean VV and VV/ICV ratio in the NPH group (91.1 mL and 45.2%, respectively) were significantly (p < 0.01) higher than those in the NV group (26.5 mL and 13.7%) and in the CVD group (44.5 mL and 17.8%). On the other hand, mean ICV values were not significantly different among the three groups. The VV was markedly decreased postoperatively (mean -40.7%), whereas the ICV was unchanged, resulting in a marked reduction in the VV/ICV ratio (mean -39.3%). INTERPRETATION: These results suggest that patients with NPH have a unique intracranial CSF distribution, with an enlarged VV and a slightly increased ICV, resulting in a high VV/ICV ratio. Shunting led to dramatic improvement in our patients. It is likely that CSF measurement can provide valuable information in the management of patients with NPH.

[A case of spontaneous cervical internal carotid artery dissection].

Dissection of the extracranial carotid artery is a recognized cause of ischemia, particularly in young persons who present with acute neurologic deficits, both transient and permanent. We describe a patient with a spontaneous dissection of the cervical internal carotid artery (ICA). A previously healthy 24-year-old man was hospitalized because of a sudden onset of right hemiparesis and consciousness disturbance. In reality, right cervical pain preceded this attack. The first brain MRI revealed a cerebral infarction in the right cerebral hemisphere including basal ganglia. A conventional angiography was performed 1 week later. The following angiographic picture was considered to be consistent with the diagnosis of cervical artery dissection: gradually tapered occlusion beginning distal to the carotid bifurcation. And MRA revealed the same finding. A cervical MRI revealed as an eccentric signal void (corresponding to the residual lumen) surrounded by a semilunar hyperintensity (corresponding to the mural hematoma) on T1- and T2-weighted images. Dynamic CT scan (D-CT) revealed an eccentric and crescent contrast enhancement (corresponding to the residual lumen) surrounded by a relative hypodensity compared with muscle (corresponding to the mural hematoma), itself surrounded by a thin annular enhancement. From these results, we diagnosed this patient with ICA occlusion for dissection of the extracranial carotid artery. But we decided this case contraindication of anastomosis because he had had a major stroke. Our findings suggest that MRA, cervical MRI and DCT provide early recognition of internal carotid artery dissection and monitoring of its resolution. Thus, these studies may guide clinical decisions according to the development of the dissection.

Dopaminergic modulation of the pressure-natriuresis response in rats.

OBJECTIVE: The present study was carried out to examine the involvement of dopamine in the pressure-natriuresis phenomenon which has been postulated as a major regulator of extracellular fluid volume and thereby arterial pressure. DESIGN: Dopaminergic modulation of the pressure-natriuresis response was studied in the innervated and denervated rat kidney, to allow a distinction between the effects of neural and extraneural dopamine. METHODS: The pressure-natriuresis response was studied in anesthetized Sprague-Dawley rats, in which neural and hormonal influences on the kidney were fixed by denervating the kidney and by intravenous infusion of aldosterone, hydrocortisone, vasopressin and norepinephrine. The innervation to the kidney remained intact in some experiments with the selective dopamine-1 antagonist SCH 23390. Urinary excretion of dopamine during the pressure-natriuresis response was also examined in the innervated and denervated rat kidney. RESULTS: Although infusion of dopamine at a dose of 2 micrograms/kg per min had no effect on the pressure-natriuresis response in rats in which neural and hormonal influences on the kidney were fixed, the slopes of the relations between urine flow, sodium excretion and mean arterial pressure in rats given 10 micrograms/kg per min dopamine were significantly greater than those found in the control rats. Renal plasma flow increased significantly in the dopamine-treated rats whilst glomerular filtration rate did not differ between the control and dopamine-treated rats. The dopamine-induced increase in the slope of pressure-natriuresis relationship and renal plasma flow were completely blocked by 0.5 micrograms/kg per min SCH 23390. However, infusion of SCH 23390 alone at 0.5 micrograms/kg per min did not significantly alter the pressure-natriuresis response in rats with either denervated or innervated kidney. In addition, urinary excretion of dopamine derived from neither neural nor extraneural origins was altered in parallel with variations in mean arterial pressure. CONCLUSION: These results suggest that exogenous administration of dopamine may affect the pressure-natriuresis response by altering the magnitude of arterial pressure-induced changes in tubular sodium reabsorption, via an action of dopamine-1 receptors. However, endogenous dopamine does not appear to be capable of modulating the pressure-natriuresis response.

Successful resection of pheochromocytoma in a hemodialysis patient.

A 45-year-old woman with a pheochromocytoma who had been on regular hemodialysis for 4 years and underwent successful surgery is described. Careful preoperative management, including the use of prazosin and weight control, was carried out to prevent severe intraoperative and postoperative cardiovascular complications. Prazosin was given at an initial dose of 0.5 mg/day, and the dosage was increased to 20 mg/day prior to surgery. The increase in intravascular volume led to a gain of 3 kg in body weight. No deterioration of the cardiovascular or respiratory function was caused by these maneuvers, and surgery was performed without significant complications except for a rapid rise of blood pressure during tumor resection. To our knowledge, only one similar case report could be found in the English literature.

Total and split renal function assessed by ultrasound Doppler techniques.

We evaluated total and split renal functions from the pattern for renal arterial blood flow detected by ultrasound Doppler in healthy subjects and patients with varying degrees of renal function and disorders other than renovascular hypertension or severe aortic valvular disease. A renal-time pulsed ultrasonic echo-Doppler device at 2.5 MHz was used with a translumbar approach. The ratio of peak diastolic (D) to systolic (S) velocity correlated well with both p-aminohippurate clearance and creatinine clearance. Acceleration time was correlated with the clearance of neither compound. To evaluate the clinical usefulness of ultrasound Doppler in the assessment of split renal function, we compared the D/S ratio with the renal function obtained by radionuclide methods for individuals. The split renal glomerular filtration rate, calculated by a method which makes use of the early renal uptake of 99mTc-diethylenetriam-inepentaacetic acid, correlated well with the D/S ratio. These results indicate that the ultrasonic measurement of renal arterial blood flow by the pulsed Doppler method should be useful for assessment of total and split renal functions.

[Evaluation of the changes in intracranial water, sodium, phosphorus metabolites and intracellular cerebral pH in rats with acute dilutional hyponatremia].

Although most prominent among the clinical manifestations associated with hyponatremia are central nervous system (CNS) symptoms, the alterations in brain function remain poorly understood. In the present study, the alterations in intracellular cerebral pH and intracranial water, sodium and phosphorus metabolites content in rats with acute dilutional hyponatremia were examined by using an in vivo nuclear magnetic resonance (NMR) technique which noninvasively provides continuous informations on intracellular phenomena. Acute dilutional hyponatremia was induced on anesthetized male Sprague-Dawley rats by intraperitoneal injection of distilled water with an initial dose of 10 ml/100 g bw, followed by an additional dose of 5 ml/100 g bw 40 min later. Arterial blood sampling and NMR measurements were made before and every 60 min after the initial injection of distilled water. The treatment with distilled water resulted in dramatic falls in serum Na, Cl and osmolality at 60 min after water loading (Na; from 143.4 +/- 2.6 to 112.3 +/- 1.3 mmol/l, Cl; from 101.02 +/- 2.2 to 78.4 +/- 5.4 mmol/l, Osm; from 306.3 +/- 5.8 to 247.3 +/- 7.3 mOsm/kg H20). 1H-NMR imaging showed the accumulation of brain water as dilutional hyponatremia developed. Intracranial Na content measured by 23Na-NMR spectroscopy decreased significantly at 60 min after of water loading to about 70% of that observed under control condition. Since it has been demonstrated that solute extrusion from the brain with resultant reduction of brain swelling occurs within 60 min after the dilution, this result may be, at least in part, explained by this protective mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

[Hyponatremia in isolated deficiency of adrenocorticotropic hormone: role of a decrease in aldosterone secretion independent of antidiuretic hormone excess].

We report a case of 47-year-old woman with an isolated deficiency of adrenocorticotropic hormone. She was admitted complaining of fatigue and frequent loss of consciousness. The patient developed severe hyponatremia (100 mEq/l) after five days of the admission. Her plasma renin activity and plasma aldosterone concentration were low though she was dehydrated. After the treatment of dehydration, plasma osmolality was low but high plasma antidiuretic hormone (ADH) level sustained. Both high urinary sodium excretion and low urinary aldosterone excretion still remained after one month of replacement therapy with prednisolone. But, glomerular filtration rate and a response of urinary volume to acute water loading were normalized. These results suggested that severe hyponatremia of the patient was caused by an inappropriate secretion of ADH and suppression of renin-aldosterone system. We consider the suppression of renin-aldosterone system was partially independent of an inappropriate secretion of ADH.

Pharmacokinetics of ofloxacin in severe chronic renal failure.

The pharmacokinetics of ofloxacin were studied in patients with severe renal impairment. In five healthy subjects and nine patients with chronic renal failure (CRF) (creatinine clearance [CCR] less than 20 ml/min) receiving 100 mg of ofloxacin orally in the fasted state, the serum concentration was measured over the subsequent 48 hours. Intracorporeal dynamics were examined, employing a one-compartment open model. Ofloxacin levels were measured using the paper disk method. The half-life of ofloxacin was markedly prolonged, to 23.1 +/- 7.0 hr in the CRF group versus 2.9 +/- 0.5 hr for healthy subjects. In the CRF group, the maximum concentration and area under the curve were greater than in healthy subjects. There were no significant differences in volume of distribution between the two groups. The renal clearance of ofloxacin decreased from 261.0 +/- 46.6 ml/min in healthy subjects to 8.0 +/- 4.7 ml/min in the CRF group and correlated significantly with CCR in the CRF group (r = .88, P less than 0.01). There were no significant differences in nonrenal clearance between the two groups. The 24-hour renal excretion of ofloxacin averaged 91.9 +/- 5.4% and 14.1 +/- 5.5% of the dose in the healthy and CRF groups, respectively. In three hemodialysis patients on the regular hollow-fiber dialyser, the dialysance of ofloxacin was about 50% that of creatinine. Based on these findings, a reduction in the dose of ofloxacin is necessary in patients with CRF. In the hemodialyzed patients, its high dialyzability should be considered when deciding dose regimens.

Hodgkin's disease -- analysis of fifty-three autopsy cases.

Eight-eight autopsy cases originally diagnosed as Hodgkin's disease (HD) were reevaluated, and 53 cases were obtained as HD. Fifty three cases with HD were composed of 47 males and 7 females and 52 cases had an active disease. Frequencies of 4 subtypes such a lymphocytic predominant, mixed cellularity, lymphocytic depletion, and nodular sclerosis were found to be 24, 54, 14, and 6%, respectively at biopsy and 12, 38, 44, and 6%, respectively at autopsy, showing transition of subtype in HD. The manner of organ involvement, deviation of histologic figures between nodes and/or other organs, associated diseases including non-bacterial inflammation of lung, amyloidosis and secondary malignancy and differential diagnosis of HD from the confusing diseases observed in our series were described.