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To prospectively compare the demonstration of the intracranial optic pathway in patients with sellar/juxtasellar tumours and with clinical evidence of visual disturbance using either spoiled gradient recalled acquisition in steady state (SPGR) or conventional spin echo (CSE) T1-weighted imaging.We studied 108 patients with sellar/juxtasellar tumours presenting visual disturbance. Visualization of the optic pathway (nerves, chiasm, tracts) was compared between CSE T1-weighted coronal image and SPGR coronal image. In 18 patients, SPGR imaging was performed before and after administration of Gd-DTPA and visualization of the optic pathway was compared.On CSE T1-weighted coronal images of 108 patients with visual disturbance, the rates for visualization of the optic nerves, chiasms and tracts were 50%, 77.8% and 89.8% respectively. In contrast, on SPGR coronal image the rates were 80.6%, 96.3% and 92.6% respectively. The rates of visualization of the optic pathway were greater in non-enhanced that in those with enhancement. The rates of visualization in patients with recurrent tumours were less than those in patients with primary tumours. The rate of visualization of optic nerves in patients with meningioma was less than in patients with pituitary adenoma, craniopharyngioma or Rathke cleft cyst.The rate of visualization of optic pathway structures on SPGR imaging (without enhancement) is greater than that on CSE T1-weighted imaging. It is important to understand the accurate position of the optic pathways with using new MR modality especially in surgical planning for lesions around the sella turcica.

Noda epileptic rat (NER) is a mutant rat, found in a Crj: Wistar colony, which exhibits a tonic–clonic convulsion spontaneously about once per 30 h from 14 weeks of age. We performed modified acoustic priming, that is, repeated weekly sound stimulations from 3 weeks of age. In addition, characteristics of audiogenic seizure (AGS), and ictal/interictal electroencephalograms (EEGs) were examined. We also studied the effect of repeated weekly stimulations from 14 weeks of age on AGS susceptibility in another NER. From 9 weeks of age, the NER primed from 3 weeks of age had a high incidence (100%) of AGS: a typical seizure was composed of sudden wild running and/or jumping (WRJ) followed by clonic or tonic–clonic convulsion. The severity and the duration of the AGS were intensified and prolonged with an increase in age, respectively. By contrast, the NER repeatedly stimulated from the age of 14 weeks, rarely showed AGS (20–40%). The majority of the seizures in this NER were WRJ. The cortical and hippocampal EEG during the tonic convulsion showed a low-voltage spike–wave (5–7 Hz). This evolved into a high-amplitude spike- or polyspike-waves associated with the clonic convulsion. Immediately after cessation of the seizures, the EEG showed a flattening or diffuse slowing. In interictal EEG analysis, sporadic spikes predominantly in the hippocampus and spike–wave bursts in both the cortex and hippocampus occurred from 11 and 20 weeks of age, respectively. These results indicate that AGS susceptibility in NER can be induced consistently by modified acoustic priming and this rat strain is a new genetic model useful for experimental studies of human epilepsy.

A 20-year-old man presented with hypovolemic shock caused by abdominal injury. Cerebral hemodynamics were evaluated by transcranial Doppler (TCD) sonography. Middle cerebral artery flow velocities decreased, and the pulsatility indices increased markedly. Particularly, the waveform of the left middle cerebral artery showed a systolic peak, suggesting an increased intracranial pressure. Actual intracranial pressure was 7 mm Hg, and the cerebral perfusion pressure (CPP) was 51 mm Hg. These abnormal Doppler signals seemed to be caused by a compromise in CPP and to be aggravated by hypovolemia. The patient was discharged with a residual mild memory disturbance. Hypovolemia aggravates a reduced cerebral blood flow caused by a compromised CPP, and the waveform of TCD in a case of hypovolemic shock should be differentiated from intracranial hypertension.

Introduction We have developed a method that permits safer endovascular treatment via the femoral artery in neonates repeatedly in a short period of time, and have experienced a case of vein of Galen malformation in a neonate who made good progress without any particular complications after undergoing staged embolisation. Here, we report the procedure of this method. Materials and Methods A female neonate who was born by Caesarean operation at 37 weeks of gestation and weighted 2790 g, presented with respiratory distress, cardiac failure and pulmonary artery hypertension soon after birth. Vein of Galen malformation (choroidal type) was diagnosed by head ultrasound and cranial computed tomography. Lansjaunias’s Neonatal evaluation score was 11. Thus, endovascular embolisation was emergently performed. A 3Fr × 25cm Supersheath (Medikit Co Ltd, Tokyo, Japan) was placed in the discending aorta temporarily via a transfemoral approach, and then a 3.3Fr × 50 cm diagnostic catheter (Medikit Co Ltd, Tokyo, Japan) with a 0.025-inch guidewire was placed through the Supersheath and used for vessel selection. Selective arteriography was performed using the diagnostic catheter. The diagnostic catheter was passed into the common carotid or the subclavian artery over the guidewire and positioned in the internal carotid or the vertebral artery. The supersheath was then advanced into the aortic arch to cannulate the internal carotid or the vertebral artery over the diagnostic catheter. This time, we have achieved a less invasive embolisation with a transfemoral approach using the supersheath itself as a guiding catheter. Results We performed transvenous embolisation (TVE) after multi-staged transarterial embolisation (TAE) with the femoral artery puncture (right: 3 times; left: 2 times) (as a diagnostic catheter during the transvenous embolisation) in a short period of approximately 80 days. Subsequently, the patient demonstrated good progress without any particular complications, and was able to be safely discharged from the hospital five months after the birth, remained neurologically stable at 2 year after treatment and did not develop any new symptom related to the malformation. Conclusion With regard to neonates (low-birth-weight newborns), there is an increased risk of ischaemia in the lower limbs as a consequence of the insertion of a sheath on account of the thinness of their femoral artery. Particularly in the cases of arteriovenous fistulae such as a vein of Galen malformation, which require endovascular treatment, the blood flow to the descending aorta and femoral artery is often insufficient due to high-flow shunt. For this reason, the risk of lower limb ischaemia is presumed to be higher in low birth-weight newborns than in normal infants. Our method utilising a 3Fr supersheath appeared to be safe and effective without any fear of ischaemia in the lower limbs. We therefore conclude that the method would be useful not only for endovascular treatment in neonates, but also for angiography. Disclosures T. Nagayama: None. H. Uchida: None. Y. Nishimuta: None. K. Arita: None.

BACKGROUND Intracranial ependymal cysts are rare lesions generally located in the cerebral parenchyma, juxtraventricular region, or subarachnoid space; but no case of a purely intraventricular ependymal cyst has been reported. CASE REPORT A case of intraventricular ependymal cyst presenting with symptoms of psychosis is reported. The patient's symptoms resolved almost completely following endoscopic resection of the cyst. The embryologic basis of the development of an ependymal cyst inside the ventricle and its histologic characteristics are discussed. Possible mechanism of psychosis in this case is also discussed. CONCLUSION Minimally invasive techniques, as in this case, may be useful in refractory psychotic cases with cystic lesions.

The purpose of this study was to assess the effect of surgery on gonadal function in 42 male patients with pituitary adenomas Gonadal functions were evaluated by measuring total serum testosterone concentrations pre- and postoperatively. The subjects of the study were 20 patients with GH secreting adenoma, 7 patients with prolactinoma and 15 patients with nonfunctioning (NF) adenoma. Their ages ranged from 18 to 60 years (mean +/- SEM, 41 +/- 1.9). The serum testosterone concentration was low at less than 300 ng/dl preoperatively in 14 of 20 patients (70%) with GH producing adenoma, 6 of 7 patients (86%) with prolactinoma, and 7 of 15 patients (47%) with NF adenoma. Postoperatively, the total serum testosterone concentration was normalized in 9 of 14 patients (64%) with GH producing adenoma, one of 6 patients (17%) with prolactinoma, and 5 of 7 patients (71%) with NF adenoma. The normalization of serum GH and prolactin concentrations is indispensable for the restoration of gonadal function. It is very important to preserve the normal preoperative gonadotropin secretion by means of gentle surgery.

This study assessed the ability to diagnose carotid-cavernous fistulas (CCFs) non-invasively using magnetic resonance angiography (MRA). Both three-dimensional time-of-flight (3-D TOF) MRA and three-dimensional phase-contrast (3-D PC) MRA were compared with conventional cerebral angiography in nine patients with CCFs. CCFs were grouped according to Barrow's classification. In all cases, 3-D TOF MRA revealed an inferior petrosal sinus as a draining vein. 3-D PC MRA demonstrated a dilated and tortuous superior ophthalmic vein (SOV) and reflux of the SOV in seven patients. In conclusion, CCFs can be diagnosed with MRA alone by demonstrating the drainging veins.

The doleritic volcanic rocks, which occur in the Sub-Himalaya in east central Nepal, are represented by metric to decimetric (in thickness) sill-like bodies at several stratigraphic levels showing concordant relationship with the predominantly red coloured sedimentary rocks of Pre-Siwalik age. Chemistry of the clinopyroxenes contained in these rocks suggests that they are poor in TiO2 compared to the alkalic rocks and belong to non-alkalic and non-orogenic group basalts (judging from discriminant diagrams: Ti vs. Ca+Na and Ti+Cr vs. Ca. Whole rock chemical analyses on major oxides, trace-elements and REE characteristics (P2O5 vs. Zr and TiO2 vs. Zr plots; rock/OIT, rock/MORB, rock/chondrite spidergrams) indicate affinity to the tholeiitic field and similarity with the within plate basalts (WPB). Spidergrams, Y/Nb (2.06-2.66) vs. Zr/Nb (12.42-13.77) plots and La/Nb (1.34-2.11) ratios for the Dowar Khola volcanics show similarity to the commonly known continental flood basalts (Snake-river plain, Parana and Deccan basalts). Paleomagnetic study on the volcanic rocks reveals magnetite-based characteristic remanent directions, which have NE (SW) declinations with shallow downward (upward) inclinations after tilt-correction. The best inclination estimate of the primary thermo-remanent magnetisation yields a shallow northern paleolatitude (6.4±4.3°N) of acquisition implying the most probable age to be around 45 Ma (younger and older age limits of 35 and 50-52 Ma, respectively). Primary detrital remanent magnetisation with similar orientation is preserved in the red sandstones carried out mainly by haematite and partly by magnetite as well and indicates shallow near-equatorial northern latitudinal paleoposition of the area during the deposition of the sediments. Declination anomalies amount to 35-80° relative to the present day north and increase by an additional 15° if considered with respect to the expected Middle Eocene paleodeclination for the area suggesting a significant clockwise tectonic rotation. Considering the best defined remanence directions, the volcanic episodes and the deposition of associated sedimentary rocks took place sometimes in the lower Tertiary between the Eocene and Early Oligocene.

We evaluated the usefulness of surface anatomy scanning (SAS) in intracranial tumours, comparing it with surgical findings. We examined 31 patients with brain tumours preoperatively. The tumours included 16 meningiomas, 8 gliomas, 4 metastases and 3 others. SAS clearly demonstrated the tumours, allowing them to be distinguished from the structures of the brain surface, including oedema, except in cases of metastasis. SAS clearly demonstrated large cortical veins. SAS is useful for three-dimensional delineation of the brain surface before surgery.

Pituitary adenomas generally are regarded as benign tumours, but a part of them can invade the cavernous sinus and recur. We examined 43 pituitary adenomas for the following factors: tumour volume, endocrinological function, cavernous sinus invasion, and growth rates examined by using anti-proliferating cell nuclear antigen (PCNA) and MIB1 (a novel anti-Ki-67) as markers. There was significant correlation between PCNA- and MIB1-positive cell rates and PCNA- and MIB1-positive cell rates were higher in the three cases with rapid regrowth than in the other cases. Staining was stronger and more distinct for MIB1 than for anti-PCNA; thus, MIB1-positive cells were easily distinguished by their intense immunoreactivity. MIB1 may be useful for detecting those rare cases with rapid regrowth even when initially regarded as benign tumours. Adenomas with cavernous sinus invasion were significantly larger than those demonstrating no invasion. However, no significant difference was found in the frequency of PCNA- or MIB1-positive cells between adenomas with and without cavernous sinus invasion. These findings suggest that cavernous sinus invasion and growth rate are independent biological factors. Therefore, cavernous sinus invasion may be due to chemical factors produced by the tumour itself rather than as a result of rapid tumour growth.

We evaluated fast spin echo (FSE) sequences in dynamic and T2-weighted MRI of sellar lesions. We examined 25 patients with sellar lesions by dynamic FSE imaging (400/17, ETL 8, 256 × 128, 2 signal averages every 20 s on a 1.5 T MR unit. In 10 patients, dynamic FSE images were compared with dynamic standard spin echo (SSE) images. Thirty-eight patients were imaged with a T2-weighted FSE sequence (6000/76, ETL 16, 512 × 256, 2 signal averages). In 10 patients, T2-weighted FSE images were compared with SSE images. FSE dynamic imaging enables a two-slice acquisition and thin slice imaging without sacrificing the image quality and the acquisition time. High-resolution imaging of a T2-weighted FSE sequence enables the detection of the diaphragm in 80% of patients and the chiasm in 95%. Therefore, an FSE sequence is valuable in detecting sellar lesions and adjacent structures.

The purpose of this study was to evaluate the usefulness and advantages of gadolinium-enhanced three-dimensional phase-contrast MR venography for demonstrating the venous systems. The three-dimensional phase-contrast MR venography was performed with a velocity encoding gradient settings from 5 to 20 cm/s on 22 normal subjects. In 8 of normal subjects, gadolinium-enhanced phase-contrast MR venography was performed. 22 subjects (100%) had detectable flow in the sphenoparietal sinus, transverse sinus, basal vein, and internal cerebral vein. With a VENC setting at 10 cm/s, venous system was visualized selectively and clearly. Detection ratio in inferior petrosal sinus, superior petrosal sinus, and superior ophthalmic vein increased from 0% to 25%, from 28.6% to 62.5%, and from 28.6% to 37.5%, respectively, after administration of gadopentate dimeglumine. In conclusion, gadolinium-enhanced three-dimensional phase-contrast MR venography was useful for demonstrating the venous systems.

We compared the position of the normal pituitary gland as estimated by gadolinium (Gd)-DTPA-enhanced MRI, with its position at surgery in 40 patients with intra- and juxtasellar tumours: 22 pituitary adenomas, 4 craniopharyngiomas, 7 meningiomas, 2 germinomas, and 5 Rathke cleft cysts. In 37 of these, the normal gland showed more intense contrast enhancement than the adjacent tumour, from which it could be differentiated by Gd-DTPA-enhanced MRI, especially in the sagittal plane. The direction of displacement of the normal pituitary gland correlated well with tumour type, so that its position proved helpful in the differential diagnosis. The normal gland was typically displaced superiorly by pituitary adenomas, inferiorly by craniopharyngiomas, and anteriorly by germinomas. It showed variable displacement by Rathke cleft cysts, and was not usually displaced by meningiomas.

Acute cerebrovascular congestion after a closed head injury is significantly related to intracranial hypertension. As an indirect method of cerebral blood flow measurement; transcranial doppler sonography (TCD) provides a rapid and noninvasive assessment of cerebral haemodynamics, including hyperaemic conditions. TCD examinations was serially performed in 35 patients with severe head injury with intact cerebral circulation; i.e. the mean flow velocity (MFV) patterns of the middle cerebral artery (MCA) did not show signs of cerebral circulatory arrest such as systolic spike, to and fro, or no flow. The results showed that the MFV of the MCAs and ipsilateral extracranial internal carotid arteries (ICAs) in 9 of these patients increased sharply and pulsatility index (PI) decreased during 48-96 hours after the injury. This was soon followed by patterns of high intracranial resistance, consistent with elevated intracranial pressure (ICP) in monitored patients and acute brain swelling on repeated computed tomographic (CT) scans. The correlation between increased MFVs, decreased PIs, and cerebral haemodynamic changes leading to acute brain swelling is discussed. The number of patients who ended with severe disability, vegetative state, or death was 66% in this group of 9 patients, compared to only 34% for the 35 patients overall with severe head injury. Though the morbidity and mortality rates largely depend on the primary injury, the presence of acute cerebral swelling aggravate the grave course in these patients. And the ability of TCD to monitor the hyperaemic state prior to oedema should lead us to adjust the therapy in order to minimize the secondary insult related to intracranial hypertension.

Acute cerebrovascular congestion after a closed head injury is significantly related to intracranial hypertension. As an indirect method of cerebral blood flow measurement, transcranial doppler sonography (TCD) provides a rapid and noninvasive assessment of cerebral hemodynamic, including hyperemic condition.

With large pituitary adenomas, the optic nerves and chiasm usually lie on the tumour capsule and are displaced superiorly. We report a large invasive pituitary adenoma, with complete involvement of both optic nerves. Review of the preoperative MR images demonstrated the optic nerves, with signal intensity close to that of cerebral white matter, and different from the flow void of the basal cerebral arteries. Correlation of this observation with intraoperative findings is discussed.

Effects of hyperthermia alone and combined with bromocriptine (BC) or a somatostatin analogue (SMS 201-995) were studied in vitro on normal pituitary and pituitary tumour cells (GH3 cells). GH3 cells were more sensitive to heat than normal pituitary cells and a maximal difference in survival was obtained with hyperthermia at 42.5 degrees C for 6 h. BC had cytotoxic and antiproliferative effects on GH3 cells, whereas SMS 201-995 was not effective. Hyperthermia at 42.5 degrees C for 3 h in combination with BC enhanced selective cytotoxicity for GH3 cells. In contrast, combined treatment with hyperthermia and SMS 201-995 failed to enhance cytotoxicity for GH3 cells. The combination of hyperthermia and BC could provide improved therapeutic efficacy in patients with pituitary adenomas.

Transcranial doppler sonography was performed transorbitally in five patients clinically diagnosed as unilateral carotid-cavernous fistula. Dural arteriovenous malformation related-shunts were detected in all the patients. In the normal eyes, the only doppler signals observed at an insonation depth of 45 to 55 mm were those of the ophthalmic artery. In the affected eyes, abnormal doppler signals with relatively higher flow velocity and lower resistance were observed. In three of the cases, these abnormal signals showed a flow directed anteriorly or away from the cavernous sinus, consistent with changes in the ophthalmic veins caused by the presence of the shunts. In two cases, however, the observed flows were directed posteriorly, the normal direction of these veins. The possible explanations for this discrepancy are discussed in relation with angiographic findings. The use of transcranial doppler might provide a better understanding about hemodynamic changes in carotid cavernous fistulas.

Three cases of microprolactinoma with cavernous sinus invasion on magnetic resonance imaging are reported. High-resolution computed tomographic scans did not demonstrate the cavernous sinus involvement. Magnetic resonance imaging is indispensable to detect cavernous sinus invasion before treatment (transsphenoidal surgery or bromocriptine treatment) of a microprolactinoma.

The authors report a very rare case of pituitary adenoma producing both GH and ACTH. A 29-year-old female was admitted with obesity, amenorrhea, acromegaly, hirsutism, excessive pigmentation, acne, and diabetes mellitus. Computed tomography revealed an intrasellar tumor 16 mm in height, with a destroyed sellar floor. The blood concentrations of GH, ACTH and cortisol were increased (GH: 92 ng/ml, ACTH: 94 pg/ml, cortisol: 18.3 micrograms/dl). No diurnal variation in the amount of cortisol was observed. The urinary 17-OHCS was suppressed by 8 mg but not by 2 mg of dexamethasone. A subtotal adenomectomy was then performed through the transsphenoidal approach, which led to a sufficient reduction of both blood GH and ACTH (cortisol). Histologically the tumor was an acidophilic pituitary adenoma. Immunoperoxidase staining showed diffuse GH and sporadic ACTH producing cells, but failed to show any cells producing both hormones. The electron micrograms of neoplastic cells showed the ultrastructural characteristics of respective GH and ACTH cells. Another increase in both GH and cortisol, which occurred 19 months after the operation, has been controlled by bromocriptine administration. This case may be the first reported case of a pituitary adenoma producing both GH and ACTH, not accompanied by prolactin (PRL) hypersecretion, which has been fully confirmed endocrinologically and histopathologically.

A case of vasospasm after traumatic subarachnoid haemorrhage (SAH) is reported here. Transcranial Doppler Sonography (TCD) was used to evaluate mean flow velocity (MFV) changes of the basal cerebral arteries related to vasospasm. Acceleration of MFV of the right middle cerebral artery (MCA) indicating vasospasm was first noted on TCD evaluation, and then proved by carotid angiography (CAG). Evaluation of all TCD results revealed that the process of relaxation or normalization of the spastic artery started from the proximal side of the basal intracranial artery and gradually moving to the distal side. This interesting phenomenon could be a common process found in vasospasm cases.

Purpose: Seizures caused by hypothalamic hamartomas are usually difficult to control. Surgical removal of the lesion has been reported to be an effective therapy to control the seizures. However, surgical treatment can potentially damage the cranial nerves or the hypothalamus. Case Report: This is a report of a patient who had intractable epilepsy due to an inaccessible hypothalamic hamartoma and was subsequently treated with stereotactically directed irradiation by using a gamma-knife unit. This 25-year-old man had a history of intractable gelastic and tonic-clonic seizures for the last 23 years. His seizures started with a transient atony of his trunk and extremities at age 6 months. Soon they became associated with gelastic attacks with utterances followed by short generalized tonic-clonic seizures and prolonged postictal drowsiness. He was referred to our department in August 1995, just after a seizure-related car accident. Usually, the seizures were generalized tonic-clonic convulsions following a gelastic attack, occurring 3–6 times a month while taking anticonvulsants such as carbamazepine (CBZ; 1,200 mg), valproate (VPA; 1,800 mg), and zonisamide (ZNS; 600 mg) daily. He also had automatic seizures presenting as oral automatisms, vomiting, and spitting, and these occurred once or twice a month. The blood levels of these drugs were above the minimal effective concentrations, There was no evidence of precocious puberty or any apparent mental retardation. Electroencephalography (EEG) revealed diffuse and dysrhythmic slow background activities and sporadic spike or spike-and-wave activities preferentially in the left frontal and parietal leads. Video-EEG monitoring showed generalized tonic-clonic seizures after a transient laughing attack accompanied by diffuse spike-and-wave bursts, which did not show any laterality. The current magnetic resonance imaging (MRI) as well as the MRI performed 30 months ago demonstrated a nonenhancing and non-progressive spherical mass -10 mm in diameter on the right side at the floor of the third ventricle. The lesion was irradiated with 36 Gy to the center and 18 Gy (50% isodose line) to the margin through a 4–mm and an 8–mm collimator. Two months after the irradiation, the frequency of the seizure attacks transiently increased. However, he has not had any seizures since 3 months after the therapy. Antiepileptic drugs (AEDs) have been reduced since 1 year after the irradiation. The MRI performed 1 year after the irradiation demonstrated a complete disappearance of the lesion. The patient has been seizure free for the last 17 months, with no neurologic or endocrinologic complications. The MRI examination 12 months after the irradiation showed a complete disappearance of the lesion. Conclusions: Stereotactic irradiation by-,using a gamma-knife unit appears to be a promising therapeutic option for surgically inaccessible hypothalamic hamartomas associated with intractable seizures.

Purpose: The Noda epileptic rat (NER), which was found in a colony of Crj:Wistar rats, shows spontaneous tonicxlonic convulsions at a frequency of approximately once per 30 h. However, weekly applied acoustic priming consistently induces tonic-clonic convulsion with sound stimuli. When NERs were given sound stimuli (95 dB, 8 kHz, 30 s) weekly from age 3 weeks, the percentage of animals with audiogenic seizures increased with age and was 100% after age 9 weeks. The audiogenic-response score to quantify the intensity of seizure responses also increased with age. Frontal cortical and hippocampal electroencephalograms (EEGs) showed low-voltage spike-and-wave complexes during tonic convulsions, which evolved into high-amplitude spike- or polyspike-and-wave complexes during clonic convulsion. Immediately after cessation of the seizures, the EEG showed a flattening or diffuse slowing. To elucidate the development of the seizure induction by acoustic priming, we examined the epileptiform discharges in the in-terictal EEG as a function of age. Methods: The acoustic priming was applied to NERs from age 7 to 35 weeks. Cortical and hippocampal EEGs were recorded weekly during the interictal stage for 15 min after a 15-min habituation by using implanted electrodes. Results: Sporadic spikes were observed predominantly in the hippocampus with age, although they were rarely synchronized in the cortex. Hippocampal spikes were observed in two (33.3%) of six animals at age 7–10 weeks, 23 (82.4%) of 28 animals at age 11–15 weeks, 12 (85.7%) of 14 animals at age 16–19 weeks, and 21 (100%) of 21 animals at age >20 weeks. This development of abnormal hippocampal discharges with acoustic priming was in line with the development of convulsive seizures. Conclusions: Development of hippocampal excitation induced by acoustic priming is thought to lead to the induction of convulsive seizures in the NERs.

We report two patients with deafferentation pain secondary to central nervous system lesions who were evaluated by noninvasive magnetic coil stimulation of the motor cortex followed by electrical motor cortex stimulation with epidural electrode array implantation. Magnetic coil stimulation was very useful to estimate the effect of electrical stimulation. Our first patient was a 52-year-old man who experienced a left putamenal hemorrhage at the age of 48. Two years later, he had paresthesias and intractable pain in the extremities and face on the right side. Pain was resistant to barbiturates but responded to magnetic coil stimulation of the motor cortex. Electrical motor cortex stimulation provided excellent relief from the pain. The second patient was a 43-year-old man who was suffering from congenital cerebral palsy for which left thalamotomy was performed two times, at the ages of 9 and 13. He began to experience intractable pain on the right side 20 years later. Although barbiturate administration was effective for pain relief, neither magnetic coil stimulation nor electrical stimulation of the motor cortex gave relief from pain.

Recent geochronological studies have revealed that an early Palaeozoic (around 500Ma) heating event is recognized in the Himalaya in addition to those in Tertiary age (Eocene and Miocene), late Proterozoic age (700-600Ma) and early Proterozoic age (2000-1800Ma). The early Palaeozoic event is mainly associated with granitic intrusions at the northern margin of the Indian continent, that is, in the Lesser Himalaya and Tethys Himalaya along the whole Himalaya from Sikkim in the east to Pakistan in the west (LE FORT et al. : Sci. Terre, Mem., 47,195,1986). These granites are mainly tourmaline-bearing mica leucogranites with or without cordierite and garnet, and have often changed into orthogneiss by later metamorphism in the Tertiary. Major element chemistry suggests the rocks to be S-type granites, and plots near minimum melting composition in the normative Qz-Ab-Or system. Chondrite-normalized REE patterns for the granites from the Nepal Himalaya and from the Yamato Mountains and Lutzow-Holm Bay, Antarctica show a similar pattern : (La/Lu)_=1.5-16 and clear negative Eu anomaly. In the Himalaya the sedimentary basin has been shifted from the Lesser Himalaya in the south to the Tethys Himalaya in the north in the early Palaeozoic age (HASHIMOTO et al. : Geology of the Nepal Himalayas, 257,1973). The Palaeozoic granitic intrusion appears to have occurred along the boundary zone between these basins, and to have been coeval with the shifting of the basin. Such early Palaeozoic orogenies with intensive acidic magmatism associated with slight metamorphism have been known to occur not only in East Gondwana (the Ross orogeny in Antarctica and the Adelaide orogeny in Australia) but also in West Gondwana (the Pan-African orogeny in Africa). Therefore, we propose to designate these orogenies in the whole of Gondwanaland as the Pan-Gondwana event which has been attributed to the final amalgamation of Gondwanaland in the early Palaeozoic age.

The southern slope of the central Nepal Himalayas is divided geologically by the Main Central Thrust zone into the underlying Midland metasediment zone (Lower Himalayas) in the south and the overlying Himalayan gneiss zone (Higher Himalayas) in the north. The former zone consists of a thick pile of various kinds of metasediments folded into an anticlinorium, and the latter zone consists of high-grade crystalline rocks with a north-dipping homoclinal structure and is further overlain by the Tethys Himalayas, composed of non- or slightly metamorphosed Tethyan sediments. The Main Central Thrust zone shows a characteristic lithology such as calcareous schist, quartzite, phyllitic schist and augen gneiss, and is intensely mylonitized. The mineral composition and paragenesis of the rocks in the present area indicate an inverted metamorphism from the Midland metasediment to the Main Central Thrust zones, that is, the metamorphic grade of the Midland metasediment zone increases upward toward the thrust zone from the chlorite to the biotite zones of the greenschist facies, and the greenschist-amphibolite transitional zone is attained in the thrust zone. The Himalayan gneiss zone is apparently much higher in metamorphic grade than the thrust zone. On the basis of the compositional zoning of garnets and muscovite compositions, however, it is concluded that the Himalayan gneisses suffered a polymetamorphism. The younger metamorphism resulted in a retrograde metamorphism of the Himalayan gneisses together with the above-mentioned inverted metamorphism and an anatectic melting in depth. This was caused by shear heating due to the thrust movement along the Main Central Thrust zone during the Alpine tectonism. The older metamorphism, which seems to be Precambrian in age, was much higher in metamorphic grade than the younger one and formed the pyrope-rich cores of garnets in the Himalayan gneisses. The maximum metamorphic temperature of 550°C, estimated from the mineral paragenesis, in the thrust zone, is compatible with that caused by shear heating due to the thrusting with thrusting velocity of 5–10 cm/yr, maximum stress of 300 bars and thrusting distance of 250 km (Bird, 1978).

The authors reported a patient with a large prolactinoma (PRL 1,716 ng/ml) who was treated with bromocriptine for two years and followed up for a subsequent 36 months. After the start of the therapy, the tumor size was dramatically reduced, and finally the disappearance of the tumor was confirmed by high resolution coronal CT. The serum prolactin level and pituitary function were normalized. The tumor has not regrown and the blood prolactin level has remained normal for 36 months since the discontinuation of bromocriptine administration. This is a very rare case report on the eradicative effect of bromocriptine on such a large prolactinoma. Another characteristic of this case was that the prolactin reserve was maintained not only before the therapy but also during the early stage of the therapy.

The present paper briefly deals with the lithostratigraphy and structure of the area along the motor road between Butwal and Ramdighat in central Nepal. The area consists geologocally of six formations from the base upwards the Angaha Khola Formation, Ramdi Formation. Kokat formation, Kerabari formation, Charchare Formation and Tansen Formation. The lower four formations are considered to be lower to middle paleozoic and the upper two formations to be upper Mesozoic in age. These formations are distinct from the Midland meta- sediment Group to the north. The Tansen zone composed of these formations, as well as the Piuthan zone on the west, is a peculiar geologic unit of the Nepal Himalayas.