Search

Cerebrospinal fluid (CSF) plays an essential role in maintaining the homeostasis of the central nervous system. The functions of CSF include: (1) buoyancy of the brain, spinal cord, and nerves; (2) volume adjustment in the cranial cavity; (3) nutrient transport; (4) protein or peptide transport; (5) brain volume regulation through osmoregulation; (6) buffering effect against external forces; (7) signal transduction; (8) drug transport; (9) immune system control; (10) elimination of metabolites and unnecessary substances; and finally (11) cooling of heat generated by neural activity. For CSF to fully mediate these functions, fluid-like movement in the ventricles and subarachnoid space is necessary. Furthermore, the relationship between the behaviors of CSF and interstitial fluid in the brain and spinal cord is important. In this review, we will present classical studies on CSF circulation from its discovery over 2,000 years ago, and will subsequently introduce functions that were recently discovered such as CSF production and absorption, water molecule movement in the interstitial space, exchange between interstitial fluid and CSF, and drainage of CSF and interstitial fluid into both the venous and the lymphatic systems. Finally, we will summarize future challenges in research. This review includes articles published up to February 2016.

The cavernous sinuses of 50 adult cadavers were examined to investigate the relationships of the blood vessels and cranial nerves, important structures during surgery in this sinus. The first and second divisions of the fifth cranial nerve were embedded in the deep dural layer of the cavernous sinus and were supplied by the two main branches of the intracavernous carotid artery. The meningohypophyseal artery supplied the sixth cranial nerve in Dorello's canal and the third and fourth cranial nerves where they entered the dura. The inferolateral trunk supplied the third, fourth, fifth, and sixth cranial nerves. The size of the meningohypophyseal artery was usually inversely proportional to the size of the inferolateral trunk. The capsular artery did not supply the cranial nerves. The cavernous sinus can be approached through various routes: a) superior, through the anteromedial or medial triangle; b) lateral, through the paramedial, Parkinson's, anterolateral, and lateral triangles; c) inferior, through the posterolateral and posteromedial triangles; and d) from the inferomedial walls. The choice of surgical approach depends mainly on the location of the lesion to be treated.

In two cases of entrapment of the temporal horn, computed tomography demonstrated the typical appearance of a comma-shaped homogeneous area isodense with water surrounded by a periventricular low-density area. The cause was probably choroid plexitis resulting in obstruction of the cerebrospinal fluid pathway at the atrium. External drainage followed by shunt emplacement is indicated.

A 38-year-old male presented with moyamoya disease. Occlusion of the bilateral proximal posterior cerebral arteries (PCAs) resulted in homonymous 3/4 (right half and left lower quadrant) anopsia and various mental symptoms. To prevent impending cortical blindness, revascularization to the right PCA was performed by occipital artery (OA) to calcarine artery anastomosis. His neurological state was stabilized. OA-cortical PCA (calcarine artery) anastomosis is an alternative to omentum transplantation or occipital burr hole procedures for impending cortical blindness.

Balloon compression of the left IXth and Xth cranial nerves and ventrolateral medulla oblongata in dogs resulted in statistically significant increases in blood pressure without obvious changes in cardiac output. Five of 21 hypertensive patients with trigeminal neuralgia or hemifacial spasm demonstrated normalized blood pressure following microvascular decompression for arterial compression of the brainstem in the area of the IXth and Xth cranial nerves on the left. Our experimental and clinical results suggest that neurogenic hypertension caused by the vascular compression of the medulla oblongata can be relieved by microvascular decompression.

The authors report an instance of familial moyamoya disease involving a 47-year-old female and her 18-year-old daughter, both of whom initially presented, within a 1-year period, with intracranial hemorrhage. Cerebral angiography showed the typical features of moyamoya disease. The mother, whose disease was more advanced, underwent superficial temporal-middle cerebral artery bypass, with satisfactory results. Human leukocyte antigen typing was performed in both cases. The pertinent literature is reviewed.

The authors investigated the temporal response to the enhancement by the contrast medium infusion in the computed tomography for the differential diagnosis of intracranial tumors. In ten cases of intracranial tumors (two cases of meningiomas, acoustic neurinomas, glioblastomas and metastatic cancers and one case of pituitary chromophobe adenoma and craniopharyngioma), the effect of the enhancement was examined at 15, 30, 60, 120 and 180 minutes after the infusion of the contrast medium. The results were analysed about both the enhanced figures of the lesion on the monitor TV and the estimation of the attenuation value of the lesions. The results about the enhanced figures were as follows; 1) each part of the lesion did not always show the synchronous appearance or withdrawal, 2) there were time differences in the appearance or withdrawal of the enhanced effect according to the kinds of the intracranial tumors and 3) the precise size or form of the lesions could not be sufficiently demonstrated in the early scan within 30 minutes and the delayed scan was mandatory for the precise diagnosis. According to the analysis of the attenuation response by the print-out data, glioblastomas and metastatic cancers with marked destruction of the blood-brain barrier showed late but prolonged response to the enhancement and meningiomas with rich vascular beds showed early appearance and rapid withdrawal of the response. The other tumors showed the intermediate pattern of the response. In conclusion, the analysis of the delayed scan in computed tomography will add more precise information about the differential diagnosis of the intracranial tumors.

The authors evaluated results of surgical treatment for 12 cases of prolactin-secreting pituitary microadenomas with respect to the effect on the endocrinological status and compared these results with those for 10 cases of macroadenomas. The cases of microadenomas were all female; 10 cases with amenorrhea and galactorrhea, a case with oligomenorrhea and galactorrhea and a case with only amenorrhea. Both microadenomas and macroadenomas were operated on through the transsphenoidal route. Microadenomas were considered to have been removed completely but macroadenomas were not always removed completely because of their larger size. The relation between operative findings of microadenomas and basal serum PRL levels was analysed. Two elastic and firm adenomas showed elevated serum PRL levels (p

Pheochromocytomas are functionally active tumors which occur most commonly in the adrenal medulla but which can also develop in an extra-adrenal site. Over 90% of pheochromocytomas including extra-adrenal tumors are located between the diaphragm and the pelvic floor. Only two previous reports of pheochromocytoma originating from the cervical sympathetic chain were found in the literature. A thrid case of pheochromocytoma originating from the cervical sympathetic chain is presented. The patient was a 18-year-old boy who was admitted to the Sapporo Medical College Hospital, because of attacks of palpitation, headache, generalized sweating and numbness in the four extremities during the past three years. Paroxysmal hypertention was noted and a high level of noradrenalin in plasma and urine was shown. The patient was diagnosed as having a pheochromocytoma. However, it was difficult to detect the tumor. A tumor, which was situated on the right side of the neck at the angle of the jaw became enlarged and palpable after one year. Selective angiography and CT were performed, and the tumor was removed. The tumor, which was 6×3.5×3.5 cm in size, had originated in the right superior cervical sympathetic ganglion. A pathological examination showed chromaffin paraganglioma or pheochromocytoma. The postoperative course was uneventful.

The patient, a 37-year-old female, was hospitalized with a severe headache. Neurological examination on admission revealed no deficits except for neck stiffness and somnolence. Computed tomography showed a subarachnoid hemorrhage, which was especially prominent in the supracerebellar and quadrigeminal cisterns, but demonstrated no ventriculomegaly. Cerebral angiography on admission revealed no apparent abnormalities, but repeat angiography 8 days later disclosed a saccular aneurysm (2 X 3 mm) arising from the hemispheric branch of the left superior cerebellar artery (SCA). Three days after admission, the patient developed cerebellar dysarthria, which was assumed to be due to vasospasm. On the 24th day after admission, the aneurysm was successfully clipped through the infratentorial-supracerebellar approach. The postoperative course was uneventful and the patient was discharged with no neurological deficit. Nineteen other cases of peripheral SCA aneurysm have been reported in the literature. The presence of this type of aneurysm should be considered in patients who are fairly young and have focal neurological signs, such as third or fourth nerve palsy and/or cerebellar dysfunction. The prognosis for such patients is good, except in cases in which the neurological status is poor at the onset.

The concentration of lactate, PCO2, HCO3-, Na, K, Cl and the pH of cerebrospinal fluid (CSF) and arterial blood were measured simultaneously in 104 samples obtained from 17 patients with bacterial meningitis. These values were compared with those of 12 control subjects, including patients with pituitary adenoma or individuals with non-neurological disease. Initially, patients with bacterial meningitis had significant CSF lactic acidosis, arterial respiratory alkalosis, low CSF HCO3-, low CSF and arterial Na and Cl, and high CSF K in comparison to the control group. CSF PCO2 did not differ significantly between the two groups. Subsequently, following successful treatment of meningitis, these parameters gradually normalized. The most significant correlations were found between CSF pH and CSF HCO3-, between arterial blood pH and CSF lactate, and between arterial blood PCO2 and CSF HCO3-. There was no significant relationship between electrolyte changes and the acid-base balance. In conclusion, brain metabolic changes in patients with bacterial meningitis were similar to those observed in other neuropathological states, such as head trauma and cerebrovascular disease. Assessment of lactate concentration and acid-base balance in both arterial blood and CSF was useful in differentiating bacterial meningitis from aseptic meningitis and proved to be a good indicator of intracranial microchemical status in cases of bacterial meningitis.

The authors investigated factors responsible for cessation of galactorrhea or restoration of ovulation in 30 women with PRL-secreting pituitary adenomas after surgery with or without bromocriptine. All the patients complained of sterility and 25 patients had galactorrhea. Microsurgical removal of adenomas was performed in all the patients and 15 patients received oral bromocriptine after surgery on account of sustained elevated serum PRL levels. Galactorrhea ceased in 19 out of 25 patients (76.0%) after the treatment. The PRL levels where galactorrhea ceased ranged from three to 1, 177 ng/ml. Galactorrhea ceased even at the elevated PRL levels in nine patients and four patients sustained galactorrhea at the normal PRL levels. Therefore, the normal PRL levels per se did not inevitably ensure cessation of galactorrhea after the treatment. However, the PRL level below 140 ng/ml was considered to ensure cessation ofgalactorrhea. There was no difference in the frequency of cessation ofgalactorrhea after the treatment between microadenomas and macroadenomas although there was a prevalence of microadenomas after surgery. Another favorable factor for cessation of galactorrhea was a longer postoperative interval of more than three months after surgery. Preoperative serum PRL levels, age of the patients at surgery, duration of galactorrhea, history of nursing, severity of galactorrhea and serum estradiol or progesterone levels had no correlation with cessation of galactorrhea. Ovulation was restored in 18 out of 30 patients (60.0%) after the treatment and pregnancy was established in 12 patients. The PRL levels where ovulation was restored ranged from three to 57 ng/ml. Ovulation was restored even at elevated PRL levels in seven patients and nine patients sustained anovulation at the normal PRL levels. Therefore, the normal PRL levels per se did not inevitably ensure restoration of ovulation. There was no difference in the frequency of restoration of ovulation after the treatment between patients with preoperative PRL levels below 200 ng/ml and those with the levels over 200 ng/ml, although there was a prevalence of patients with levels below 200 ng/ml after surgery. There was a prevalence in the frequency of restoration in amenorrhea Grade I, preoperative duration of sterility of less than five years, microadenomas, a longer postoperative interval normal serum basal LH levels and peak LH levels in response to LH-RH and the presence of positive feedback control to surge LH in response to estrogen. Age of the patients at surgery, elevated dopamine activity in the hypothalamus and serum estradiol or progesterone levels were not correlated with restoration of ovulation.

A 41-year-old woman had had slowly progressive loss of vision and exophthalmos of the left eye from the age of 35 years. Multiple cafe-au-lait spots and subcutaneous neurofibromatous masses were noted. Plain skull X-rays revealed a defect of the posterior wall of the left orbit and bulging of the left frontotemporal bone. There was also a small bony defect in the occipital bone adjacent to the left lambdoid suture. Computed tomography (CT) disclosed a marked deformity of the left middle cranial fossa and a bony defect in the posterior wall of the left orbit. Three-dimensional CT was extremely useful in the planning of the surgical repair. The posterior orbital wall defect, which was approached through a left frontotemporal craniotomy, was covered with a resin plate, and the exophthalmos was corrected under direct vision. The bulging frontotemporal bone was resected and replaced by a resin plate. Postoperatively, the exophthalmos was markedly reduced and the patient regained light perception in the left eye.

A 58-year-old male was admitted following an episode of unconsciousness. Nine years prior to this, he had undergone surgery and radiation therapy for a nasal tumor. Subsequently, he had undergone surgical excision of recurrent nasal tumors and metastases to the cervical lymph nodes. The final pathological diagnosis was paraganglioma. On admission, he had no neurological deficit other than anosmia. Laboratory studies showed no abnormalities in urinary concentrations of vanillylmandelic acid or catecholamines. Computed tomography (CT) demonstrated a calcified, heterogeneously enhanced mass in the anterior ethmoid sinus and bilateral frontal fossa. Cerebral angiography revealed a mesh-like tumor stain. Through a bifrontal craniotomy the intracranial tumor was totally removed. It was hypervascular and clearly demarcated from the surrounding cerebral tissue. The pathological diagnosis was paraganglioma without malignant features. Radiation therapy was administrated postoperatively at a total dose of 5060 rads, and follow-up CT showed regression of the ethmoid sinus tumor. As of 2 years postoperatively, the tumor has not recurred.