Is there an ideal shunt? A panoramic view of 110 years in CSF diversions and shunt systems used for the treatment of hydrocephalus: from historical events to current trends.

OBJECT: The goal of this study is to evaluate whether an "ideal shunt" exists. METHODS: This is a retrospective analysis based on original papers in the field of Hydrocephalus and Shunts. Patients of all age groups, who had hydrocephalus, and underwent some form of CSF diversion were included. The study has been divided into four stages: from 1900 to 1949, 1950 to 1974, 1975 to 1999, and from 2000 to 2010. RESULTS: In stage 1 (historical era): Saphenous vein grafts, rubber conduits, and other materials were used in CSF diversions. In 1949, the first implantable shunt tube was developed by Nulsen. In stage 2 (experimental stage): the Holter valve was developed. Newer innovations were developed in relation to the ventriculo-atrial shunt, which was the preferred CSF diversion. In stage 3 (developmental stage), a large number of different design shunt systems were developed, with the aim of reducing complications. The ventriculo-peritoneal shunt had become the preferred CSF diversion. Also, the programmable valve was born. In stage 4 (era of programmable valve, there is a preference for the use of programmable shunt systems. However, shunt failure rate at 1 year being around 25 to 40%, and shunt survival at 1 and 2 years are 50-70 and 47-53% in most series. CONCLUSION: Every shunt is an ideal shunt provided the choice of the shunt used should be made by the matching performance of the shunt system to the altered profile of CSF dynamics of a given patient. The most important factor being the opening pressure.

Classification of hydrocephalus: critical analysis of classification categories and advantages of "Multi-categorical Hydrocephalus Classification" (Mc HC).

OBJECTIVE: Hydrocephalus is a complex pathophysiology with disturbed cerebrospinal fluid (CSF) circulation. There are numerous numbers of classification trials published focusing on various criteria, such as associated anomalies/underlying lesions, CSF circulation/intracranial pressure patterns, clinical features, and other categories. However, no definitive classification exists comprehensively to cover the variety of these aspects. The new classification of hydrocephalus, "Multi-categorical Hydrocephalus Classification" (Mc HC), was invented and developed to cover the entire aspects of hydrocephalus with all considerable classification items and categories. MATERIALS AND METHOD: Ten categories include "Mc HC" category I: onset (age, phase), II: cause, III: underlying lesion, IV: symptomatology, V: pathophysiology 1-CSF circulation, VI: pathophysiology 2-ICP dynamics, VII: chronology, VII: post-shunt, VIII: post-endoscopic third ventriculostomy, and X: others. From a 100-year search of publication related to the classification of hydrocephalus, 14 representative publications were reviewed and divided into the 10 categories. RESULTS AND DISCUSSION: The Baumkuchen classification graph made from the round o'clock classification demonstrated the historical tendency of deviation to the categories in pathophysiology, either CSF or ICP dynamics. CONCLUSION: In the preliminary clinical application, it was concluded that "Mc HC" is extremely effective in expressing the individual state with various categories in the past and present condition or among the compatible cases of hydrocephalus along with the possible chronological change in the future.

Aggressive large cell medulloblastoma extending to the extracranial region in brain-dead state.

INTRODUCTION: The authors describe the case of a 29-month-old boy who presented with acute non-communicating hydrocephalus caused by a small tumor in the fourth ventricle. He became brain-dead immediately and remained stable in that condition. MATERIALS AND METHODS: Six months later, despite being in a brain-dead state, a rapid direct tumor extension from the intracranial to extracranial region was observed, and chemoradiotherapy was performed following tumor biopsy. The histopathological diagnosis was large cell medulloblastoma. Although treatment was initially effective, the tumor again aggressively invaded the cervical muscles via the spinal canal. Comparative genomic hybridization (metaphase) analysis revealed a pattern of aberrations predictive of a poor prognosis (+1q, ?17p, +17q, and probable amplification of c-myc gene), and he eventually died 11 months after onset. RESULTS: Direct invasion of medulloblastoma from the intracranial to extracranial region is extremely rare, and, to our knowledge, this is the first report of medulloblastoma exhibiting rapid extension to the extracranial region in brain-dead state. CONCLUSIONS: For patients with medulloblastomas, careful observation is needed even in brain-dead state. The etiology of this rare condition as well as the genetic characteristics responsible for aggressive tumor behavior are discussed.

Guideline for management and treatment of fetal and congenital hydrocephalus: Center Of Excellence-Fetal and Congenital Hydrocephalus Top 10 Japan Guideline 2011.

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).

Myeloschisis repair in a premature neonate with a birth weight of 599 g.

This report describes the case of a neonate with myeloschisis weighing 599 g that underwent an operation for spinal cord reconstruction resulting in substantial neuronal functional recovery. At 28 weeks of gestation, oligohydramnios was detected and the female fetus was diagnosed with intrauterine growth retardation. At birth by emergency caesarean section, she showed lumbosacral myeloschisis and complete paralysis of the lower extremities. Surgical repair and spinal cord reconstruction was performed 2 days after birth by closing the neural placode. Total blood loss was only 2 ml. Within 3 months of the operation, lower extremity neurologic function gradually improved down to the level of the knee joint. To our knowledge, this case is the lowest recorded body weight for a neonate with myeloschisis repair at birth, and this further suggests the possibility of improvement of lower extremity neurologic function after birth and surgical reconstruction.

[Clinical prognosis and therapeutic aspects in management of pediatric moyamoya disease].

We reviewed the clinical prognosis and therapeutic aspects in the management of pediatric moyamoya disease from our data base for the last 8 years since establishment of our institution. We found 99 cerebrovascular disease cases among the total of 1,159 cases, and 20 out of them were moyamoya disease. Only 13 cases were analyzed as the rest were not available for follow up. Nine girls and 4 boys were admitted with an average age of 5 years-old 4 months. Initial symptom were TIA in 5, cerebral infarction in 5, migraine in 2, and epilepsy in one. The type of moyamoya disease was bilateral type in 10 cases, and unilateral type in 3 cases. Clinical condition and investigations, as well as the effect of conservative management, required surgery in 9 cases (8 indirect revascularization and one direct-bypass surgery), and the rest 4 cases were managed conservatively. Only 10 cases were followed-up, 9 operated cases and one conservatively managed case. In 6 of 9 of the operated cases, there was recurrence: cerebral infarction in 3, TIA recurrence in 2 and epileptic seizure in one. On MRA a steno-occlusive lesion of PCA was found in 4 of the 6 recurrence patients, and improvement was achieved by additional surgery in one of them. All of the cases developed good postoperative collateral circulation. The conservatively treated patient did not show neither steno-occlusive lesion of PCA, nor a clinical recurrence for 7 years observation. Therefore, posterior circulation system in moyamoya disease is important as a collateral circulation in addition to the revascularization procedures, and we believe that the progression of the steno-occlusive lesion of PCA is an important indicator, predicting recurrence.

Intradural arteriosynangiosis in pediatric moyamoya disease: modified technique of encephalo-duro-arterio-synangiosis with reduced operative damage to already growing revascularization.

OBJECTIVE: Various operative procedures have been described for the treatment of pediatric moyamoya disease. However, the majority of invasive or radical procedures proposed have focused primarily on revascularization and few have discussed to maximizing preservation of the already growing neovascular network. METHODS: This present procedure describes the supratemporal artery is anastomosed to the inner layer of the dura mater and surrounded by the outer layer as a sandwich with a blunt procedure of dural layer separation. RESULTS: This technique efficiently established an anastomotic connection between the supratemporal artery and the cortical brain, and the dura mater postoperatively with maximally preserving the existing vascular network. CONCLUSION: IDAS, the modified surgical technique of EDAS, shall be benefit in preserving the already developed collateral circulation, and underlying structure over the brain cortex as much as possible, which is important particularly in pediatric moyamoya patients.

Prenatal diagnosed cyst of the quadrigeminal cistern in Aicardi syndrome.

Aicardi syndrome is an X-linked dominant disorder characterized by the pathognonomic association of three clinical signs: agenesis of the corpus callosum, infantile spasms, and chorioretinal lacunae. This is a severe syndrome with an estimated survival rate of 76% at 6 years and 40% at 14 years and a maximum developmental level like a 12-month-old baby in 91% of cases. We illustrate a case of Aicardi syndrome with bilateral, small chorioretinal lacunae, infantile spasms with a typical hypsarrhythmia, defects of thoracic vertebra and bilateral absence of the 12th rib associated with an arachnoid cyst of the quadrigeminal cistern, and presence of the corpus callosum with a favorable outcome.

Diagnosis of congenital hydrocephalus and delivery of its patients in Japan.

The study population included 193 patients with prenatally diagnosed (fetal) hydrocephalus and 181 with postnatally (12 or less than 12 months after birth) diagnosed (infantile) hydrocephalus identified by a nationwide questionnaire survey of congenital hydrocephalus performed in 2000. Of 180 patients with fetal, 101 (56.1%) were diagnosed before week 32 of gestation and 18 (10%) were diagnosed week 37 and later of gestation. In patients with fetal hydrocephalus, US was used in more than 80% of the cases, whereas in patients with infantile hydrocephalus, CT was used in more than half of the cases. For diagnosis of fetal hydrocephalus, either US or MRI had become dominantly utilized and CT had gone out of use in 1996-2000. The adoption ratio of cesarean delivery to transvaginal delivery was around 7 to 3 in patients with fetal hydrocephalus, and 2 to 7 in patients with infantile hydrocephalus, respectively, with significant difference between fetal hydrocephalus and infantile hydrocephalus groups (p < 0.001). Clinical outcomes in patients with fetal hydrocephalus was better in those delivered transvaginally than in those by cesarean delivery, although without no statistical significance (p = 0.124) and those in patients with infantile hydrocephalus showed almost no difference between transvaginal and cesarean delivery groups. There was a tendency for the Apgar score at 5 min to be lower in smaller birth weight infants with a body weight of less than 2000g. This score could be useful as an index for predicting immediate postnatal death in patients with fetal hydrocephalus.

New transparent peel-away sheath with neuroendoscopic orientation markers. Technical note.

The peel-away sheath in neuroendoscopic surgery offers numerous advantages and has many potential applications. However, currently available nontransparent sheaths have a critical disadvantage in that disorientation can occur, given the limited visible operative field. To overcome this obstacle, the authors have developed and clinically applied a new transparent sheath with "navigational orientation markers." The clear peel-away sheath provides a transparenchymal route, parenchymal protection, and, most importantly, direct visualization of the surroundings along the whole trajectory and at the distal edge. The navigational orientation markers add further benefits in terms of facilitating orientation in the endoscope trajectory, making this tool extremely useful in neuroendoscopic surgery.

Traumatic subacute subdural effusion in the posterior fossa associated with secondary acute hydrocephalus in a neonate. Case report.

The authors report on a neonatal patient with traumatic subacute subdural effusion in the posterior fossa associated with secondary acute hydrocephalus. The infant fell from his mother's hand onto the floor, injuring his left parietal region. Computed tomography (CT) scans of the patient's head revealed a linear fracture of the left parietal bone, a small contusion in the right temporal lobe, and a small subdural hematoma in the right posterior fossa with thin subdural effusion. Serial CT scans revealed a progressive increase in subdural effusion bilaterally in the posterior fossa. On Day 7 the anterior fontanelle was tense and CT scans revealed marked hydrocephalus associated with thick subdural effusion in the posterior fossa. External drainage of both the subdural effusion and dilated lateral ventricles improved the patient's condition, and no reaccumulation of subdural effusion has been observed. The origin and treatment of this rare clinical entity is discussed.

Dynamic motion analysis of fetuses with central nervous system disorders by cine magnetic resonance imaging using fast imaging employing steady-state acquisition and parallel imaging: a preliminary result.

OBJECT: The authors present a novel cine magnetic resonance (MR) imaging, two-dimensional (2D) fast imaging employing steady-state acquisition (FIESTA) technique with parallel imaging. It achieves temporal resolution at less than half a second as well as high spatial resolution cine imaging free of motion artifacts for evaluating the dynamic motion of fetuses in utero. The information obtained is used to predict postnatal outcome. METHODS: Twenty-five fetuses with anomalies were studied. Ultrasonography demonstrated severe abnormalities in five of the fetuses; the other 20 fetuses constituted a control group. The cine fetal MR imaging demonstrated fetal head, neck, trunk, extremity, and finger as well as swallowing motions. Imaging findings were evaluated and compared in fetuses with major central nervous system (CNS) anomalies in five cases and minor CNS, non-CNS, or no anomalies in 20 cases. Normal motility was observed in the latter group. For fetuses in the former group, those with abnormal motility failed to survive after delivery, whereas those with normal motility survived with functioning preserved. The power deposition of radiofrequency, presented as specific absorption rate (SAR), was calculated. The SAR of FIESTA was approximately 13 times lower than that of conventional MR imaging of fetuses obtained using single-shot fast spin echo sequences. CONCLUSIONS: The following conclusions are drawn: 1) Fetal motion is no longer a limitation for prenatal imaging after the implementation of parallel imaging with 2D FIESTA, 2) Cine MR imaging illustrates fetal motion in utero with high clinical reliability, 3) For cases involving major CNS anomalies, cine MR imaging provides information on extremity motility in fetuses and serves as a prognostic indicator of postnatal outcome, and 4) The cine MR used to observe fetal activity is technically 2D and conceptually three-dimensional. It provides four-dimensional information for making proper and timely obstetrical and/or postnatal management decisions.

Huge arachnoid cyst of the occipital cerebral convexity.

A 68-year-old woman presented with a rare huge right occipital cystic lesion manifesting as progressive left hemiplegia. Cranial computed tomography revealed a 4 x 7 cm right occipital lobe thin-walled cyst with midline shift and compression of the ipsilateral ventricle. The patient underwent a single burr hole operation for cystography and delineation of the cyst anatomy, then a separate right parieto-occipital craniotomy with complete cyst evacuation, corticotomy, and ventriculostomy. The presumptive diagnosis was arachnoid cyst. The symptoms had completely resolved by 4 months after surgery with nearly normal neuroimaging appearance after 7 months. Cystography followed by craniotomy and ventriculostomy may be effective for supratentorial arachnoid cysts.

Spontaneous regression of syringomyelia in Hajdu-Cheney syndrome with severe platybasia. Case report.

Hadju-Cheney syndrome (HCS) is a rare autosomal-dominant disorder with variable expressivity. It is characterized by facial dysmorphism, premature tooth loss, osteolysis of distal phalanges, and skull abnormalities. In some cases, progressive platybasia can occur and can lead to Chiari malformation with an obstruction of cerebrospinal fluid flow. To the best of the authors' knowledge, only five cases of HCS-associated syringomyelia have been reported in the literature. Because of the rarity of this association, little is known about its natural history. The authors present the case of a 16-year-old boy affected by HCS. On initial magnetic resonance (MR) imaging, a severe basilar invagination with Chiari malformation and cervicothoracic syringomyelia was documented. The syringomyelia had no clinical manifestations. A repeated MR image demonstrated a spontaneous resolution of the syrinx with no changes in the tonsil or the platybasia. The regression of the syringomyelia was confirmed by a control MR imaging examination performed after a 2-year period. No changes in the patient's clinical conditions were found during the follow-up period. This is the first case of spontaneous regression of the syringomyelia despite a severe platybasia in HCS. It did not appear correlated to a modification of the tonsil's structure or position. This observation illustrates one possible evolution of syringomyelia in the natural history of HCS and raises the question of the potential mechanisms involved in the spontaneous drainage of the syringomyelic cavity.

Frameless free-hand maneuvering of a small-diameter rigid-rod neuroendoscope with a working channel used during high-resolution imaging. Technical note.

A newly designed small-diameter rigid-rod neuroendoscope was created to evaluate the applicability of free-hand maneuvering during high-resolution imaging. The neuroendoscope was designed as a light, handheld tool weighing 550 g. A 20-cm-long objective lens, 2 mm in diameter, is placed in the lower two thirds of the single-space lumen of an oval-shaped outer sheath, 16.5 mm long and 3.5 x 2.5 mm at maximum diameter. Included are microinstruments of 1.3-mm diameter for various neuroendoscopic procedures, including microscissors, biopsy forceps, grasping forceps, monopolar coagulator/cutting rod, and bipolar coagulator that can be introduced through the upper one third of the lumen. Because the endoscope is held steady in the surgeon's left hand, with the handle gripped at the base, quick back-and-forth movements can be made along the long axis, via a peel-away sheath inserted to the ventricle, shifting of the endoscope tip to the side of the objective target will be minimal. Given the instrument's unified configuration, the surgeon will never lose orientation during maneuvering. Using the farthest right of three inlet/outlet orifices, the short and handy semiflexible microinstruments can be guided and controlled by the surgeon's right hand. After experience in 66 cases in which various neuroendoscopic procedures yielded excellent operative outcomes (morbidity rate in complications related to the endoscopic procedure 0%; mortality rate 0%), the endoscope prototype was finalized in the ideal form for frameless maneuvering that uses a rigid-rod endoscope. The "gun-butt" holder for use with the operator's left hand provides stability and allows the endoscope to be handled with improved control. These new aspects of the neuroendoscope and surgical technique offer substantial improvement over the flexible-steerable fiberoptic endoscopes.

Neuroendoscopic transventricular ventriculocystostomy in treatment for intracranial cysts.

OBJECT: Although in recent years endoscopic procedures have been used for intracranial arachnoid cysts with favorable preliminary results in certain locations, optimal surgical treatment is still controversial. The purpose of this study was to evaluate the efficacy and safety of endoscopic transventricular ventriculocystostomy in the treatment of intracranial cysts based on the concept of normalizing cerebrospinal fluid (CSF) dynamics. METHODS: Twelve symptomatic pediatric patients with congenital intracranial cysts underwent surgery at Jikei University in Tokyo. A neuroendoscopic transventricular ventriculocystostomy was performed in nine patients and an endoscope-assisted craniotomy in the remaining three. Endoscopy was performed using a freehand maneuver with a newly designed rigid-rod neuroendoscope that is frameless and has a small diameter. Clinical results were good in all patients, although cysts in three were not prominently reduced in size when follow-up imaging studies were performed. Neither death nor symptomatic morbidity occurred, and no patient required shunt placement. In three cases the endoscopic fenestration was associated with an endoscopic third ventriculostomy (ETV). Postoperative CSF dynamics studies consisting of computerized tomography ventriculocysternography, and pre- and postoperative cine-mode magnetic resonance imaging demonstrated free communication between fenestrated cysts and ventricular/ cistern CSF pathways consistent with normalization of CSF dynamics. CONCLUSIONS: Neuroendoscopic transventricular ventriculocystostomy constitutes a valid alternative to microsurgery for intracranial cysts located within or adjacent to the ventricles. It creates an effective CSF flow within the cyst with minimal alteration of subarachnoid spaces. It may be combined with an ETV procedure in case of obstruction of CSF pathways and should be preferred to the insertion of shunts.

Endoscopic third ventriculostomy in patients with cerebrospinal fluid infection and/or hemorrhage.

OBJECT: In this study the authors evaluate the safety, efficacy, and indications for endoscopic third ventriculostomy (ETV) in patients with a history of subarachnoid hemorrhage or intraventricular hemorrhage (IVH) and/or cerebrospinal fluid (CSF) infection. METHODS: The charts of 101 patients from seven international medical centers were retrospectively reviewed; 46 patients had a history of hemorrhage, 42 had a history of CSF infection, and 13 had a history of both disorders. All patients experienced third ventricular hydrocephalus before endoscopy. The success rate for treatment in these three groups was 60.9, 64.3, and 23.1%, respectively. The follow-up period in successfully treated patients ranged from 0.6 to 10 years. Relatively minor complications were observed in 15 patients (14.9%), and there were no deaths. A higher rate of treatment failure was associated with three factors: classification in the combined infection/hemorrhage group, premature birth in the posthemorrhage group, and younger age in the postinfection group. A higher success rate was associated with a history of ventriculoperitoneal (VP) shunt placement before ETV in the posthemorrhage group, even among those who had been born prematurely, who were otherwise more prone to treatment failure. The 13 premature infants who had suffered an IVH and who had undergone VP shunt placement before ETV had a 100% success rate. The procedure was also successful in nine of 10 patients with primary aqueductal stenosis. CONCLUSIONS: Patients with obstructive hydrocephalus and a history of either hemorrhage or infection may be good candidates for ETV, with safety and success rates comparable with those in more general series of patients. Patients who have sustained both hemorrhage and infection are poor candidates for ETV, except in selected cases and as a treatment of last resort. In patients who have previously undergone shunt placement posthemorrhage, ETV is highly successful. It is also highly successful in patients with primary aqueductal stenosis, even in those with a history of hemorrhage or CSF infection.