Persistent Primitive Hypoglossal Artery with Ipsilateral Symptomatic Carotid Artery Stenosis and Cerebral Aneurysm.

OBJECTIVE: Persistent primitive hypoglossal artery (PPHA) is a rare type of persistent carotid-basilar anastomosis sometimes associated with other vascular lesions. We treated an extremely rare case of PPHA with concomitant ipsilateral symptomatic cervical internal carotid artery (ICA) stenosis and unruptured aneurysm. CASE PRESENTATION: A 67-year-old woman visited our institution with acute onset of diplopia. Magnetic resonance imaging revealed multiple acute infarctions in the right anterior and posterior circulations. Digital subtraction angiography demonstrated the right PPHA concomitant with ipsilateral cervical ICA stenosis and an unruptured ICA aneurysm with maximum diameter of 8 mm. The multiple infarctions were considered to result from artery-to-artery embolism due to microthrombi from the ICA plaque passed along the PPHA, so carotid endarterectomy was performed as the first step with preoperative modified Rankin Scale (mRS) grade 1. During the operation, the patient had impaired ICA perfusion due to internal shunt catheter migration into the PPHA followed by acute infarction in the right hemisphere causing mild left hemiparesis. The patient was transferred to the rehabilitation hospital with mRS grade 3. After 3 months of rehabilitation, the patient recovered to mRS grade 1 and clipping surgery for the unruptured right ICA aneurysm was performed as the second step with uneventful postoperative course. CONCLUSION: The treatment strategy should be carefully considered depending on the specific blood circulation for such cases of PPHA with unique vasculature.

The metopic-sagittal craniosynostosis-report of 35 operative cases.

PURPOSE: We have diagnosed 35 cases of the supposedly rare condition metopic-sagittal synostosis in the past 20 years. Here, we introduce their clinical symptoms, neuroradiological findings, and surgical treatment methods, as well as discuss the relevant literature. METHODS: Subjects included 35 patients (33 boys and 2 girls; mean age 4.2 years; range 1-8 years). Magnetic resonance imaging (MRI) confirmed that there were no abnormal findings in the brain. Thirty patients presented with symptoms including speech delay, hyperactivity, autistic tendency, motor impairment, self-mutilation, and panic/temper tantrum behaviors. No other congenital malformation was observed, and all cases were considered to be the non-syndromic type. The final diagnosis was made using three-dimensional computed tomography (3D-CT) scans. The surgery was done the fronto-orbital advancement in addition to remove the large parts of sphenoid bones including sphenoid ridges at the skull base and trimmed the calvarium as necessary to reduce pressure. RESULTS: Surgical intervention improved clinical symptoms in nearly all 35 patients; cosmetic problems in patients with scaphocephaly were also corrected. CONCLUSIONS: In the cases of child patients with metopic-sagittal synostosis who had clinical symptoms, surgical intervention improved such symptoms, suggesting its potential utility for metopic-sagittal synostosis with clinical symptoms. A surgical procedure focusing on the skull base was important for our successes. Based on the fact that metopic-sagittal synostosis was diagnosed in 35 patients at one institution over a relatively short period of time, this pathological condition may not be as rare as is currently believed.

In vitro performance of the fixed and adjustable gravity-assisted unit with and without motion-evidence of motion-induced flow.

BACKGROUND: Anti-siphon devices and gravitational-assisted valves have been introduced to counteract the effects of overdrainage after implantation of a shunt system. The study examined the flow performance of two gravitational-assisted valves (shunt assistant - SA and programmable shunt assistant - proSA, Miethke & Co. KG, Potsdam, Germany) in an in vitro shunt laboratory with and without motion. METHODS: An in vitro laboratory setup was used to model the cerebrospinal fluid (CSF) drainage conditions similar to a ventriculo-peritoneal shunt and to test the SA (resistance of +20 cmH2O in 90°) and proSA (adjustable resistance of 0 to +40 cmH2O in 90°). The differential pressure (DP) through the simulated shunt and tested valve was adjusted between 0 and 60 cmH2O by combinations of different inflow pressures (40, 30, 20, 10, and 0 cmH2O) and the hydrostatic negative outflow pressure (0, -20, and -40 cmH2O) in several differing device positions (0°, 30°, 60°, and 90°). In addition, the two devices were tested under vertical motion with movement frequencies of 2, 3, and 4 Hz. RESULTS: Both gravity-assisted units effectively counteract the hydrostatic effect in relation to the chosen differential pressure. The setting the proSA resulted in flow reductions in the 90° position according to the chosen resistance of the device. Angulation-related flow changes were similar in the two devices in 30-90° position, however, in the 0-30° position, a higher flow is seen in the proSA. Repeated vertical movement significantly increased flow through both devices. While with the proSA a 2-Hz motion was not able to induce additional flow (0.006 ± 0.05 ml/min), 3- and 4-Hz motion significantly induced higher flow values (3 Hz: +0.56 ± 0.12 ml/min, 4 Hz: +0.54 ± 0.04 ml/min). The flow through the SA was not induced by vertical movements at a low DP of 10 cmH2O at all frequencies, but at DPs of 30 cmH2O and higher, all frequencies significantly induced higher flow values (2 Hz: +0.36 ± 0.14 ml/min, 3 Hz: +0.32 ± 0.08 ml/min, 4 Hz: +0.28 ± 0.09 ml/min). CONCLUSIONS: In a static setup, both tested valves effectively counteracted the hydrostatic effect according to their adjusted or predefined resistance in vertical position. Motion-induced increased flow was demonstrated for both devices with different patterns of flow depending on applied DP and setting of the respective valve. The documented increased drainage should be considered when selecting appropriate valves and settings in very active patients.

In vitro performance and principles of anti-siphoning devices.

BACKGROUND: Anti-siphon devices (ASDs) of various working principles were developed to overcome overdrainage-related complications associated with ventriculoperitoneal shunting. OBJECTIVE: We aimed to provide comparative data on the pressure and flow characteristics of six different types of ASDs (gravity-assisted, membrane-controlled, and flow-regulated) in order to achieve a better understanding of these devices and their potential clinical application. METHODS: We analyzed three gravity-dependent ASDs (ShuntAssistant [SA], Miethke; Gravity Compensating Accessory [GCA], Integra; SiphonX [SX], Sophysa), two membrane-controlled ASDs (Anti-Siphon Device [IASD], Integra; Delta Chamber [DC], Medtronic), and one flow-regulated ASD (SiphonGuard [SG], Codman). Defined pressure conditions within a simulated shunt system were generated (differential pressure 10-80 cmH2O), and the specific flow and pressure characteristics were measured. In addition, the gravity-dependent ASDs were measured in defined spatial positions (0-90°). RESULTS: The flow characteristics of the three gravity-assisted ASDs were largely dependent upon differential pressure and on their spatial position. All three devices were able to reduce the siphoning effect, but each to a different extent (flow at inflow pressure: 10 cmH2O, siphoning -20 cmH2O at 0°/90°: SA, 7.1 ± 1.2*/2.3 ± 0.5* ml/min; GCA, 10.5 ± 0.8/3.4 ± 0.4* ml/min; SX, 9.5 ± 1.2*/4.7 ± 1.9* ml/min, compared to control, 11.1 ± 0.4 ml/min [*p < 0.05]). The flow characteristics of the remaining ASDs were primarily dependent upon the inflow pressure effect (flow at 10 cmH2O, siphoning 0 cmH2O/ siphoning -20cmH2O: DC, 2.6 ± 0.1/ 4 ± 0.3* ml/min; IASD, 2.5 ± 0.2/ 0.8 ± 0.4* ml/min; SG, 0.8 ± 0.2*/ 0.2 ± 0.1* ml/min [*p < 0.05 vs. control, respectively]). CONCLUSION: The tested ASDs were able to control the siphoning effect within a simulated shunt system to differing degrees. Future comparative trials are needed to determine the type of device that is superior for clinical application.

Genetic studies of myelomeningocele.

INTRODUCTION: Myelomeningocele is one of the major congenital malformations involving the central nervous system. It is caused by a disruption of the neural tube closure, which is completed at 3-4 weeks of gestation. DISCUSSION: Multidisciplinary approach is necessary to treat and support this malformation which is a huge burden to the patient, family, and the society. This is a characteristic anomaly that it is known that taking folic acid during the periconceptional period, it is possible to reduce the risk of having a neural tube defect (NTD). Although folate fortification had dramatically reduced the incidence, it was not possible to diminish the risk. To date, many studies have been conducted focusing on candidate genes related to folate and glucose metabolism. We will describe a brief review of genetic etiology of candidate genes of metabolic pathways of folate and glucose, animal models of NTDs, and finally recent studies of microRNA.

Cervical Extradural Arteriovenous Fistula without Intradural Drainage Successfully Treated with Endovascular Treatment Using Both Transvenous and Transarterial Approach: Case Report and Review of Literatures.

The classification of spinal extradural arteriovenous fistulas (AVFs) was reported based on a case series treated by microsurgery in 2009 and endovascular interventions in 2011. The present report describes a patient with extradural AVFs at the cervical spine manifesting gradual progressive radiculomyelopathy of bilateral upper extremities. Magnetic resonance imaging (MRI) revealed a mass sign from C1 to C4 at the right ventral side and the spinal cord was deviated to the left and indicated as a flow void sign. Diagnostic angiography revealed an extradural AVFs located at the C1-C4 level that was supplied by bilateral radicular artery from the vertebral artery (VA) and right ascending cervical artery (ACA). The shunting points were recognized multiply at C2/3 and C3/4 levels on the right. The transvenous embolization to the enlarged extradural venous plexus around the shunting points via right hypoglossal canal and the transarterial embolization against multi-feeders of the branch of left radicular artery, right ACA achieved complete occlusion of the lesions. His symptom was gradually recovered, and angiography performed 2 weeks after embolization showed no recurrence. When the arteriovenous shunts in the upper cervical spine were high flow shunts, transvenous approach via the hypoglossal canal might be one option for the treatment of spinal extradural AVFs.

Full-Endoscopic Transcervical Ventral Decompression for Pathologies of Craniovertebral Junction: Case Series.

Odontoidectomy is very effective for the decompression of the ventral craniovertebral junction (CVJ). Various approaches are available for the direct ventral decompression of the CVJ. Because there are many disadvantages of open transoral approach, endoscopic odontoidectomy was developed. There are 3 approaches in endoscopic odontoidectomy. We report transcervical retropharyngeal endoscopic approach for the ventral CVJ in this paper. Three patients with different pathologies received operations using this approach. The decompression was enough and surgical invasion was less in all patients. Each endoscopic approach has some advantages and different working regions due to their approach trajectories, but transcervical retropharyngeal approach is very familiar for our neurospinal surgeons and has a relatively large working area. This approach might have the chance to take the place of open transoral approach for endoscopic spinal surgeons.

Clinical outcome and radiological findings after cervical open door laminoplasty with titanium basket.

OBJECT: Cervical laminoplasty, which is well described in the Japanese literature, is the gold standard for decompressing multilevel spinal cord compression. Several spacers have been introduced to provide enough decompression of the spinal canal and reconstruct the stable posterior elements. The purpose of this study was to retrospectively evaluate radiological outcomes after open door laminoplasty using the titanium spacer (Laminoplasty Basket: L-Basket; Ammtec, Tokyo). METHODS: Between July 2014 and June 2016, 31 patients with cervical spondylotic disease, including OPLL, were underwent open door laminoplasty with this device. All patients were clinically assessed by JOA score. The average follow-up period was 48.9 months with a range of 37-60 months. Postoperative radiological evaluation revealed bone union on both the open side and the gutter side from 12 months to 36 months after surgery on computed tomography. RESULTS: The clinical outcome improved from 10.9 points on the Japanese Orthopaedic Association scale to 15.8 points at 3 months after surgery and there were no significant major complications such as the implant failure. The bone union rate of the gutter side was 85.9% (85/99) at 1 year, 96.0% (95/99) at 3 years after surgery and of the open side was 57.6% (57/99) at 1 year, 89.9% (89/99) at 3 years after surgery. Circumferential fusion was confirmed 85.9% (85/99) of the time. CONCLUSION: This titanium spacer seemed to have the potential of promoting bone union between the spacer and both lamina, and lateral mass in cervical laminoplasty which is a safe procedure with satisfactory clinical results.

Efficacy of Atlantoaxial Transarticular Screw Fixation Using Navigation-Guided Drill: Technical Note.

BACKGROUND: Atlantoaxial transarticular screw fixation (TASF) is a procedure that involves inserting screws vertically into the articular processes of C1 and C2. However, this procedure is associated with a risk of injury to surrounding structures including the vertebral artery, carotid artery, pharynx, and spinal cord by misinserting K-wires or screws. This study was performed to evaluate the risk of TASF using 3-dimensional navigation-guided drilling and screw insertion tract creation. METHODS: Three patients underwent the surgical procedure using a navigation system guided by intraoperative computed tomography. The insertion tract of the screw was created using the navigation system to avoid penetration of the C1 anterior arch or damage to the vertebral artery. A blunt-tipped guide wire was used, which was safe to advance to the cortex of the anterior arch of C1. RESULTS: There were no complications or instrument failures in any of the surgeries. In each case, the total radiation dose delivered was 5.31-7.02 mGy, and total radiation exposure time was 55.6-106.8 seconds. Bone fusion was achieved in all cases. CONCLUSIONS: TASF using a navigation system for drilling is useful for accurate placement of K-wire and preventing damage of the vital structures, lowering the risk of the procedure.

Endoscopic and Microsurgical Treatment of Sylvian Fissure Arachnoid Cysts-Clinical and Radiological Outcome.

OBJECTIVE: A Sylvian fissure arachnoid cyst (SAC) is a well-recognized location for an intracranial arachnoid cyst in the pediatric population. For those cysts, which can rupture and be accompanied by a subdural hygroma or hematoma, several treatment modalities have been reported. We report clinical and radiological outcome of fenestration of these cysts by either endoscopy or microsurgery. METHODS: A retrospective review of the database of operative procedures revealed 24 procedures (20 endoscopic and 4 microsurgical procedures) to fenestrate a SAC at university hospitals in Berlin, Germany and Tokyo, Japan. RESULTS: With the applied technique, a reduction of SAC volume of more than 10% was achieved in 83.3% of all patients. The median volume of SACs (n = 24) was significantly reduced from 83.5 mL (range 21-509 mL) preoperatively to 45.5 mL (range 8.4-261 mL; P < 0.01) after 3.5 months and to 29.0 mL (range 0-266 mL; P < 0.01) after 15 months. In children (n = 8) with a ruptured SAC the combined extraaxial volume of a SAC and accompanying hygroma/hematoma was reduced from 166 mL (range 111-291 mL) before surgery to 127 mL (range 87-329 mL) after 2 months and to 77 mL (range 25-140 mL; P < 0.05) after 11 months. Acute clinical symptoms were generally resolved postoperatively; headaches were resolved or improved in 75%. A significant association of resolution or improvement of headaches and volume reduction was demonstrated. CONCLUSIONS: The study demonstrated efficacy in a predominantly endoscopically treated patient cohort with Sylvian fissure arachnoid cysts, as indicated by improvement of clinical symptoms and diminished radiological SAC volume after treatment.