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Object: Young patients with moyamoya disease frequently exhibit extensive cerebral infarction at the time of initial presentation, and even in the early postoperative period. To investigate clinical characteristics in the early postoperative period, the authors prospectively analyzed findings of MR imaging, MR angiography, and SPECT before and after surgery. The authors focused in particular on how postoperative neurological deterioration occurred., Methods: Between August 2005 and June 2009, 22 patients younger than 18 years of age with moyamoya disease were treated at Miyagi Children's Hospital. The mean patient age (+/- SD) was 8.58 +/- 4.55 years (range 2-17 years). Superficial temporal artery-middle cerebral artery bypass and indirect bypass of encephalosynangiosis between the brain surface and the temporal muscle, galea, and dura mater were performed in 35 hemispheres. Magnetic resonance imaging and MR angiography were performed before surgery, at 7 days postoperatively, and 3-6 months after surgery. A (123)I-isopropyl iodoamphetamine SPECT scan was also obtained pre- and postoperatively., Results: During the postoperative period, neurological deterioration was observed after 15 operations (10 cases of motor paresis, 1 of aphasia, and 4 of sensory disturbance) in 13 patients. All symptoms had resolved by the time of discharge, except in 2 patients who suffered cerebral infarction. All patients exhibited disappearance (94.3%) or reduction (5.7%) of transient ischemic attacks (TIAs) during the follow-up period. Perioperative studies revealed 2 different types of radiological findings, focal uptake decrease on SPECT indicative of cerebral ischemia due to dynamic change in cerebral hemodynamics caused by bypass flow, the so-called watershed shift, and perioperative edematous lesions on MR imaging due to cerebral hyperperfusion. The frequent occurrence of preoperative TIAs was significantly associated with watershed shift, whereas preoperative MR imaging findings and preoperative SPECT findings were not. Age at operation was the only factor significantly associated with postoperative hyperperfusion., Conclusions: In young patients, moyamoya disease exhibits rapid progression, resulting in poor clinical outcome. The risk of postoperative neurological deterioration in very young moyamoya patients with frequent TIAs should be noted. The findings in this study showed that direct bypass is not completely safe in patients with moyamoya disease because it causes dynamic change in postoperative cerebral hemodynamics.

We present a rare case of a symptomatic large extradural arachnoid cyst extending from the lower thoracic to sacral region in a 12-year-old boy, who presented with the signs and symptoms of spinal cord compression over 4 years. Since the pedicle of the cyst could not be delineated using conventional magnetic resonance imaging (MRI), cine-mode MRI, and computed tomography scan, partial resection of the cyst was initially performed, which significantly improved motor function. After the first operation, a single pedicle was clearly demonstrated by 3D constructive interference in steady state (CISS) MRI. Thus, additional surgery aimed at closing the dural defect was performed to prevent future enlargement of the cyst. The operative findings were consistent with those of 3D CISS imaging. Clinical and radiological features of this lesion are discussed, focusing on the usefulness of 3D CISS MRI for preoperative evaluation, and especially for delineating the pedicle in cases of large extradural spinal arachnoid cysts.

We report a case of successfully treated glossopharyngeal neuralgia, in whom preoperative magnetic resonance imaging (MRI) with a sequence of constructive interference in steady-state (CISS) precisely delineated microvascular compression to the glossopharyngeal nerve at its cisternal portion. A 70-year old female experienced paroxysmal and excruciating pain, starting in the right ear and descending to the tongue and throat. The pain was brief, burning and triggered by swallowing food and drinks. Preoperative CISS-MRI delineated a small vascular loop compressing the glossopharyngeal nerve at its cisternal portion. The patient was diagnosed with glossopharyngeal neuralgia, and then, microvascular decompression surgery was performed. Intraoperative inspection revealed that the glossopharyngeal nerve root was in contact with a small arterial loop at its cisternal portion and was deformed as demonstrated by preoperative CISS-MRI. The glossopharyngeal nerve was displaced using a piece of Teflon felt, freeing it from the arterial loop compression. The patient's neuralgia resolved immediately after surgery. During a period of 2-years follow up, no recurrence of the neuralgia has occurred. The usefulness of CISS-MRI for the diagnosis of glossopharyngeal neuralgia is discussed.

Unlabelled: The differential diagnosis between inflammatory demyelinating disease and malignant glioma is difficult based only on neuroimaging methods., Methods: Four patients with inflammatory demyelinating disease who presented with clinical and neuroimaging findings strongly suggestive of malignant glioma were examined., Results: MRI showed a mass lesion with prolonged T1 and T2 values and gadolinium enhancement in all cases. Proton MR spectroscopy and (201)Tl SPECT showed findings supportive of the diagnosis of malignant glioma in all cases. However, surgical biopsy revealed inflammatory demyelinating disease. After the diagnosis, 2 patients were treated by steroid administration and 2 were just observed. The gadolinium enhancement of all lesions decreased and finally disappeared., Conclusion: Such cases illustrate the importance of considering a demyelinating lesion in the differential diagnosis of a mass lesion. The difficulties encountered in establishing the correct diagnosis of inflammatory disease are related to the variations in the radiologic appearance, which require exclusion of gliomas or other brain tumors by surgical biopsy before the therapeutic strategy can be selected.

Objective: To assess the value of constructive interference in steady-state, three-dimensional, Fourier transformation (CISS) magnetic resonance imaging in the endoscopic management of hydrocephalus and intracranial cysts., Methods: CISS imaging and T2-weighted imaging were performed for 14 consecutive patients before and after fenestration procedures, using a flexible endoscope, to treat loculated or multiloculated hydrocephalus (4 patients), aqueductal stenosis or obstruction (4 patients), arachnoid cysts (4 patients), a cyst of the velum interpositum (1 patient), or an ependymal cyst (1 patient). Fifteen fenestration procedures were performed, including one reoperation., Results: Preoperative CISS imaging demonstrated intracystic intraventricular septa not observed with conventional T2-weighted imaging for 11 of 15 procedures and provided better brain tissue/cerebrospinal fluid contrast, allowing better understanding of the cause of hydrocephalus and the nature of the cysts. CISS imaging and T2-weighted imaging were equally useful for monitoring postoperative changes in the sizes of ventricles or cysts and the presence of flow voids after third ventriculostomies. However, only CISS imaging clearly demonstrated the site of fenestration for six of the nine patients who underwent fenestration procedures., Conclusion: CISS imaging provides excellent cerebrospinal fluid/brain tissue contrast, allowing detailed study of the anatomic features of the ventricular system and cystic lesions. CISS imaging is valuable for both preoperative decision-making and postoperative evaluation.

Purpose: To evaluate the MR and CT features of pediatric supratentorial intra-axial tumors with respect to differential diagnosis and the role of each investigation modality., Material and Methods: MR and CT findings in 40 children with 12 types of pathologically proven histological tumors were reviewed., Results: The location of tumors might be one clue to differential diagnosis. In our material, cysts (60%), calcifications (45%), and intratumoral hemorrhages (27%) were found in the tumors. Characteristic features noted in some lesions included: peritumoral hemosiderin deposition in cavernous angiomas; intratumoral flow void in a choroid plexus carcinoma and in glioblastomas; and hemicerebral atrophy in germinomas. A comparison between malignant and benign tumors showed perifocal edema and a mass effect to be significantly more common in malignant lesions. Homogeneous enhancement suggested a benign tumor and an inhomogeneous pattern represented malignancy, while the lack of obvious enhancement did not always suggest benignity. Intratumoral calcium deposition was a not uncommon finding in malignant tumors., Conclusion: In most cases, the exact diagnosis should be made by histological examination but it is important for treatment planning that the appropriate depiction of tumor extension and tissue characterization be made by MR and CT.

We report a case of moyamoya disease associated with Down syndrome and congenital heart malformations. Findings of cranial MR imaging indicated cortical laminar necrosis along with cerebral infarction. To explain the development of these findings, we hypothesized that hypoxic brain damage manifesting cortical laminar necrosis was caused by hypoperfusion of the brain due to occlusive changes to the cerebral vessels in moyamoya disease, in addition to a state of general hypoxemia secondary to congenital heart malformations.

Two cases of lissencephaly were prenatally diagnosed by a magnetic resonance image (MRI). Smooth surface of brain and remarkable sylvian fissure, which were barely detectable by ultrasound, were easily observed in MRI. MRI is the most appropriate tool in diagnosing lissencephaly.

Diastemstomyelia is an extremely rare disorder that is seldom found among the Japanese. This paper presents two Japanese patients, a newborn male and a newborn female, with diastematomyelia. CT demonstrated bony spurs more clearly than plain film, and magnetic resonance images indicated split cords and associated anomalies. Although the embryogenesis of diastematomyelia has not been clearly elucidated, the coincidence of levels of associated anomalies and diastematomyelia in our cases and in the literature supports Bremer's embryogenetic explanation of persistent accessory neurenteric canal.

Background.There is controversy about extensive surgical treatment for a malignant astrocytic tumour in more elderly patients who may have poorer outcomes and higher complication rates. This retrospective study investigated outcome in elderly patients with malignant astrocytic tumour before and after the adoption of routine clinical use of magnetic resonance (MR) imaging.Methods.During 1982 through 1999, 88 patients with malignant astrocytic tumour aged 60 years or over were treated in our institute. Thirty-seven patients had an anaplastic astrocytoma and 51 had a glioblastoma. Thirty-seven patients treated from 1982 to 1988 did not have pre-operative evaluation by MR imaging (Group A), 26 patients treated from 1989 to 1995 had preoperative MR imaging evaluation (Group B), and 25 patients treated after 1996 underwent preoperative MR imaging with functional brain mapping and intra-operative navigation system monitoring (Group C).Findings.The median survival time was 8.8 months in Group A, 12.7 months in Group B, and 17.6 months in Group C. Patients with glioblastoma in Group B (11.7 months, n = 15) and Group C (16.0 months, n = 19) had significantly longer median survival time than in Group A (6 months, n = 17) (P = 0.0054 between Groups A and B, P = 0.0024 between Groups A and C). Better preoperative performance status, more thorough surgical resection, and better performance status after the initial treatment was obtained after the introduction of MR imaging, and patients with the optimal indicators showed significantly longer survival time compared with the patients without these factors.Interpretation.Pre-operative MR imaging may contribute to longer survival time by providing an earlier diagnosis in patients with better performance status, by allowing more thorough surgical resection, and resulting in better performance status after the treatment. [ABSTRACT FROM AUTHOR]

Summary. We report a case of neurohypophyseal germinoma appearing as predominantly granulomatous reaction in the first histological examination. A 12-year-old boy presented with diabetes insipidus, panhypopituitarism, and bitemporal hemianopsia. Transsphenoidal exploration for the intrasellar mass lesion extending to the suprasellar region was performed in May 1999. Histological examination revealed granulomatous hypophysitis and corticosteroid therapy was initiated. Six months later, the lesion relapsed despite corticosteroid therapy. Subtotal removal of the lesion was performed via an anterior interhemispheric approach in December 1999. Histological examination revealed typical germinoma. Subsequently, the patient underwent irradiation of 20 Gy to the tumour site and 24 Gy to the whole brain. Magnetic resonance imaging confirmed tumour remission. We must consider the possibility of neurohypophyseal germinoma in patients with granulomatous hypophysitis which does not respond to corticosteroid therapy, and perform re-exploration for more specimens to achieve the correct diagnosis. [ABSTRACT FROM AUTHOR]

Summary. A 19-year-old man with a pure germinoma in the pineal region was successfully treated with chemotherapy followed by 24 Gy local irradiation. Eight months later, magnetic resonance (MR) imaging detected ventricular wall dissemination outside the radiation field. Near complete response was achieved again after 28.8 Gy whole brain and 24 Gy whole spine irradiation. Two months later, MR imaging demonstrated recurrence of a mass at the corpus callosum. Gamma knife radiosurgery did not control this mass, so tumour resection was performed. Histological examination revealed immature teratoma. Enlargement of the recurrent mass at the trigone of the left lateral ventricle was found in spite of additional chemotherapy. Tumour extirpation was performed and histological examination revealed embryonal carcinoma. The patient died of tumour progression 34 months after the initial treatment. By a combination of chemotherapy regiments in use today, the initial radiation field to treat intracranial germinomas should not be confined to the tumour bed. [ABSTRACT FROM AUTHOR]