Search

Moyamoya disease (MMD) is a rare steno-occlusive disease of the bilateral internal carotid arteries that predominantly occurs in East Asia. Since the first description of the MMD by Suzuki and Takaku in 1969, significant advances have been made in both basic and clinical understanding of the disease. The incidence and prevalence of pediatric MMD have increased, potentially due to improved detection rates. The advancement of neuroimaging techniques has enabled MRI-based diagnostics and detailed visualization of the vessel wall. Various methods of surgical treatments are successful in pediatric MMD patients, and recent studies emphasize the importance of reducing postoperative complications since the goal of MMD surgery is to prevent future cerebral infarction and hemorrhage. Long-term outcomes following appropriate surgical treatment in pediatric MMD patients have shown promising results, including favorable outcomes in very young patients. Further studies with a large patient cohort are needed to establish individualized risk group stratification for determining the optimal timing of surgical treatment and to conduct multidisciplinary outcome assessments., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To analyze the long-term efficacy of the ventriculoatrial shunt (VAS) in pediatric patients with hydrocephalus, focusing on the atrial catheter and suitable revision procedures of the distal catheter following VAS malformation performed at our institution., Methods: The authors retrospectively analyzed data of 28 pediatric patients under the age of 10 years who were treated with VAS for hydrocephalus and who had a follow-up period of at least 5 years., Results: A total of 42 atrial tube revision procedures were performed in 28 patients during the study period. The median atrial tube survival time due to atrial tube obstruction was 2.32 years (n = 31, range: 0.4-8.08 years). Atrial tube survival time was shorter in younger children (p < 0.0001) and in children who were shorter in height (p = 0.0001). As a revision procedure following atrial tube malfunction, 22 (78.6%) out of the 28 patients who had an inserted VAS had the VAS reconversion into a VPS at the last follow-up., Conclusions: VAS can be a useful alternative to VPS, but it requires frequent atrial tube revisions, especially in younger children. Reconversion to VPS after VAS malfunction is a reasonable option and is associated with longer shunt survival time despite its previously observed difficulties.

Introduction: Hydrocephalus does not indicate a single clinical entity, but includes a variety of clinicopathological conditions caused by excessive cerebrospinal fluid (CSF) based on the disturbed circulation. Recent progress in prenatal neuroimagings such as MRI and ultrasound echoencephalography on fetus enables to understand clinicopathological conditions of CSF circulation disorder in conjunction with morphological changes in the central nervous system properly. It has been revealed that the CSF dynamics develop in the theory of evolution from the immature brain, as in the animals with the minor CSF pathway predominance, towards matured adult human brain together with the completion of the major CSF pathway: the "Evolution Theory in CSF Dynamics". Now, we can analyze CSF circulation dynamically and also analyze the flow velocity and direction of CSF movement. CENTER OF EXCELLENCE-FETAL HYDROCEPHALUS TOP 10 JAPAN: Along with this technical improvement, the standards of clinicopathological evaluation of hydrocephalus as well as the classification and concept of hydrocephalus shall undergo a major upgrade. Based on such remarkable improvement in the recent practical diagnostic evaluation of fetal hydrocephalus, it is now required to update the guideline for management and treatment of fetal and congenital hydrocephalus, and a nationwide study group; Center of Excellence-Fetal Hydrocephalus Top 10 Japan, was organized in 2008 in Japan. The retrospective analysis of 333 cases of congenital hydrocephalus indicated a fact that 43% of these cases were diagnosed prenatally, and the majority of cases were treated in these top 10 institutes in Japan. Now, congenital hydrocephalus diagnosed immediately after birth is regarded as to be based on embryonic stage; brain disorder in patients with congenital hydrocephalus should be considered in conjunction with neuronal mature process of embryonic stage. The fact is supported by the current trends in hydrocephalus research represented by "Perspective Classification of Congenital Hydrocephalus" and "Multi-categorical Hydrocephalus Classification". The ultimate goal of hydrocephalus treatment remains achieving arrested hydrocephalus by shunt surgeries. In the future, to achieve arrested hydrocephalus, minimum quantity of CSF to be drained should be elucidated. Consideration for accurate operative indication of ETV along with new neuroendoscopic device development and analysis of CSF circulation is expected in the future. The data in this prospective multicenter analysis in this guideline are credited in Oxford Evidence level 2b (Grade II).

Objects: The aims of the study were (1) to review the pathological findings of spinal lipomatous masses associated with congenital spinal dysraphism and (2) to discuss the pathological diagnosis., Methods: The pathological records of 47 patients at our institution were reviewed, and three illustrative cases were presented., Conclusion: Spinal tumorous lesions associated with spinal dysraphism have been traditionally described as lipoma since they are composed mostly of fatty tissue. However, they are different from lipomas arising in other part of the body in that they often contain various tissues of ecto- and mesodermal origin. In our study, we detected such heterotopic components in 24 out of 47 cases. Although they are also similar to teratoma, it is generally accepted that they are malformative lesions which lack neoplastic potential. We therefore should diagnose them as hamartoma rather than lipoma or teratoma.

Objective: The aim of the present study was to establish the usefulness of the fronto-basal approach with a relatively small craniotomy window for the removal of tumors protruding from the sellar-suprasellar region to the third and basal cistern., Method: Forty-two patients who were surgically treated for craniopharyngiomas extending outside the sellar-suprasellar region were evaluated. All the patients were operated on by the fronto-basal interhemispheric approach, and the average follow-up period was 5 years., Results: Gross total resection of the lesion was achieved in 30 cases. Eight patients underwent subtotal resection and four patients underwent partial removal due to recurrence after previous surgeries with or without radiotherapy. In the immediate postoperative period, major complications, including impairment of the cranial nerves, were observed in two cases. One patient exhibited transient memory disturbance due to infarction of the perforator; after 3 months, this symptom was ameliorated. Three of the patients died during follow-up; however, 6 of the 30 undergoing gross total removal and 10 of the 12 patients undergoing subtotal or partial removal suffered regrowth. Ultimately, a total of 12 patients underwent re-operation with the same approach or combined with the orbito-zygomatic approach., Conclusion: In our experience, the fronto-basal interhemispheric approach, even through a small craniotomy window, is a valid choice for the removal of craniopharyngiomas extending outside the sellar-suprasellar region. Using this approach, tumors can be removed without significant sequelae related to surgical technique due to easy preservation of the pituitary stalk, hypothalamic structures, and perforators. This approach offers a safe and minimally invasive means of treating craniopharyngiomas.

Case Report: A 2-year-old girl presented with repaired cloacal exstrophy and a subcutaneous mass at the midline of the lumbosacral region. Neurological examination revealed mild paraparesis with bilateral lower-extremity hyperreflexia and sensory disturbance below the level of L4. A CT scan showed asymmetrical spina bifida on the right side extending from L2 to L5, and symmetrical spina bifida below S1. Magnetic resonance imaging showed a low-set conus with terminal syringohydromyelia, lumbosacral lipoma, and the extradural arachnoid cysts at Th12-L4 compressing the spinal dural sac from behind. Surgical removal of the arachnoid cyst and lipoma relieved spinal dural sac compression and the tethered spinal cord. The patient showed an improvement in the lower-extremity hyperreflexia postoperatively., Conclusion: The rare association of the cloacal exstrophy with the multiple spinal cord abnormalities as shown in the present case indicates that detailed routine screening of the spinal cord is necessary for the careful planning of treatment in patients with anorectal anomalies.

An 18-year-old boy presented with an immature neurohypophysial teratoma occurring 10 years after total resection of a mature pineal teratoma through an occipital transtentorial approach in 1989. Thorough histological examination had revealed a mature teratoma. He developed panhypopituitarism and diabetes insipidus in 1999. Magnetic resonance imaging revealed a suprasellar tumor occupying the third ventricle. This tumor was totally resected through a frontobasal approach. Histological examination revealed an immature teratoma. This tumor occurred in a different site from the initial tumor and was considered to be de novo and thus a so-called metachronous germ cell tumor. Patients with completely resected mature teratoma require extended follow-up, including periodic magnetic resonance imaging, because of the risk of such a metachronous germ cell tumor.

A 2-year-old girl presented with an anterior sacral meningocele completely occupied by an epidermoid tumor. Preoperative magnetic resonance imaging had shown the meningocele with contents of the same intensity as cerebrospinal fluid. Surgery via a posterior sacral approach disclosed the tumor beneath an unexpected membrane inside the meningocele. Additionally, the presence of pus inside epidermoid tumor suggested that possible episodes of asymptomatic meningitis or other infection might have occurred before treatment, these being the major complication in anterior sacral meningocele. Therefore, we recommend that surgical treatment should be performed at the earliest possible stage in childhood, once the diagnosis is established, and dural plasty carried out to prevent infectious complications.

Infantile myofibromatosis (IM) is a proliferative disorder of infancy and early childhood characterized by the nodular or diffuse growth of lesions that are comprised of a mixture of mesenchymal elements. Intracranial involvement is reportedly rare, only eight such patients having been reported to our knowledge. We report on a 4-year-old boy with intracranial IM with a mass in his left temporal bone. A previous report on intracranial IM proposed that the underlying dura mater should be resected because of the possibility of early recurrence. At surgery in this case, the tumor was noted to be located in the bone itself and did not arise from the underlying dura. Therefore, the underlying dura mater and venous sinus were preserved. The follow-up MRI showed no sign of recurrences. It may not to be necessary to resect the dura mater in patients with intracranial IM.

In purpose of clarifying the risk factors of perioperative ischemic complications in cases with moyamoya disease, a retrospective study was conducted on the perioperative care of 36 patients who underwent vascular reconstruction for moyamoya disease. Following surgery, 8 patients developed ischemic complications (5 with minor completed strokes and 3 with transient ischemic attacks). Three factors including the presence of a preoperative low density area (LDA), intra-operative urinary output, and a reduction in the hematocrit significantly differed with complications and those without. In an evaluation of individual cases, intra-operative hypercapnia, hypotension, and a reduction in the circulating blood volume also were identified as potential factors associated with complications. On the basis of these findings, it was concluded that it is necessary to infuse an adequate amount of fluids, maintain normocapnic and normothermic states, and actively correct anemia in patients undergoing vascular reconstruction for moyamoya disease. It is also necessary to pay particular attention to perioperative care in patients in whom a LDA is detected by preoperative CT.

We retrospectively reviewed the imaging features of an aberrant course of the internal carotid artery (ICA) in one patient and its unilateral absence in four. Absence of the ICA was initially detected by MRI and MR angiography in both patients who underwent these examinations. CT revealed an abnormal or absent carotid canal in all cases. Radiological diagnosis by MRI and MR angiography could play an important role in the diagnosis.

To clarify the differences between childhood-onset moyamoya disease and that with onset in adulthood, we studied the clinical course and angiographic findings of adult patients (over 20 years of age) with moyamoya disease of childhood onset (up to 15 years of age). The clinical course in 25 patients could be assessed. The follow-up period was 5-27 years. Neurological deficits were noted in 11/23 and mental disorders in 9/21. In all except one, the illness had started before the age of 7 years. Neither neurological nor mental condition changed during or after adolescence (15-20 years of age). Two patients died of intracranial hemorrhage. The disease progressed in angiographic stage until adolescence, but had stabilized or almost stabilized by the age of 20 years. This study indicates that moyamoya disease with onset in childhood carries high morbidity and mortality. The disease advances in angiographic stage between childhood and adolescence, but stabilizes or almost stabilizes between adolescence and adulthood.

Cerebral blood flow in seven infants with extracerebral fluid collections was investigated using single photon emission computed tomography (SPECT) with 123I-N-isopropyl-p-iodoamphetamine. Early and delayed SPECT imaging was carried out. Areas of hypoperfusion were observed in five cases. The watershed zone of the major cerebral arteries or the territory of the anterior cerebral arteries were common areas of low perfusion. The hypoperfusion area was redistributed in two cases with intracranial hypertension. Subduroperitoneal shunts produced improvement of clinical symptoms in these cases. Hypoperfusion without redistribution was observed in three patients. In these areas, permanent tissue damage caused by a primary disease existed. Normal circulation patterns were observed in two patients. They showed normal development and follow-up CT revealed a decrease in the size of the extracerebral fluid collection. Measurement of regional cerebral blood flow may be helpful in considering surgical indications and in following up extracerebral fluid collection in infants.

A cooperative study was undertaken in the Tohoku district of Japan to investigate the relatively rare phenomenon of cerebral infarction in children. The purpose of the present paper is to describe the cerebral angiographic findings in 48 children whose ischemic lesions were confirmed by CT scan. The majority of lesions were considered to be idiopathic. The areas of cerebral infarction appearing in the CT scans were located in the territory of the middle cerebral artery including the basal ganglia. Angiographical abnormalities were observed in 40 patients (83%). The majority occurred in the supraclinoid portion of the internal carotid artery and in the cisternal portion of the middle and anterior cerebral arteries. Multiple lesions, such as in the C1, A1, and M1 or the C1, M1, and M2 segments were observed in 22 cases. These lesions generally appeared in continuation; no bilateral intracranial lesions were observed. Repeated angiography was performed in 22 cases, and in 55% of these some recovery of the lesions was seen.

This report describes a rare case of primary cerebral venous dysgenesis in a 3-year-old child with development retardation. Angiography resulted in nonvisualization not only of deep cerebral veins but also of superficial cerebral veins. In computed tomography and in magnetic resonance imaging the collateral venous circulation appeared as a strange configuration in the pineal region. Single photon emission computed tomography using N-isopropyl-p-[I-123]-iodoamphetamine revealed decreased regional cerebral blood flow in the basal ganglia and thalamus, but cerebral infarction was not detected in the area. These features indicate that in this case, dysgenesis of deep cerebral veins, which probably occurred during prenatal life, had caused hypoperfusion in the deep cerebral regions.

In this study, regional cerebral blood flow (rCBF) and the cerebral metabolic rate of oxygen (rCMRO2) were measured using positron emission tomography (PET) with oxygen-15 radiopharmaceuticals to clarify the pathophysiology of ventriculomegaly in the developing brain. Four hydrocephalic infants without severe neurological deficit were studied. Hypoperfusion was observed in the frontal, parietal, and visual association cortices which surrounded dilated anterior or posterior horns of the lateral ventricle. Lower rCMRO2 values than adult rates were observed in all cases. In the infants with markedly enlarged anterior or posterior horns, the surrounding cortices showed relatively lower rCMRO2 values with the fall of rCBF. Postoperative studies were performed in two infants. rCMRO2 increased in every region after ventriculoperitoneal shunting, but little change was observed in rCBF. These results indicate that metabolic deterioration occurs in the developing brain with hydrocephalus.

The cerebral blood flow and cerebral metabolic rate of oxygen (CBF and CMRO2) of three cases of childhood moyamoya disease were examined by positron-emission-computed tomography for the purpose of investigating the mechanism of the "re-build-up" phenomenon on EEG. Decrease in both CBF and CMRO2 were observed following hyperventilation. However, dissociation between the decrease in CBF and CMRO2 was also observed. Arterial blood-gas analysis disclosed hypocapnea during hyperventilation and hypoxia following hyperventilation. These results clearly indicate that the re-build-up seen on EEG is the manifestation not only of ischemic hypoxia but also of hypoxic hypoxia characteristically seen in moyamoya disease.