Satoshi Ikeuchi

Robotic digital subtraction angiography systems within the hybrid operating room.

BACKGROUND:Fully equipped high-end digital subtraction angiography (DSA) within the operating room (OR) environment has emerged as a new trend in the fields of neurosurgery and vascular surgery. OBJECTIVE:To describe initial clinical experience with a robotic DSA system in the hybrid OR. METHODS:A newly designed robotic DSA system (Artis zeego; Siemens AG, Forchheim, Germany) was installed in the hybrid OR. The system consists of a multiaxis robotic C arm and surgical OR table. In addition to conventional neuroendovascular procedures, the system was used as an intraoperative imaging tool for various neurosurgical procedures such as aneurysm clipping and spine instrumentation. RESULTS:Five hundred one neurosurgical procedures were successfully conducted in the hybrid OR with the robotic DSA. During surgical procedures such as aneurysm clipping and arteriovenous fistula treatment, intraoperative 2-/3-dimensional angiography and C-arm-based computed tomographic images (DynaCT) were easily performed without moving the OR table. Newly developed virtual navigation software (syngo iGuide; Siemens AG) can be used in frameless navigation and in access to deep-seated intracranial lesions or needle placement. CONCLUSION:This newly developed robotic DSA system provides safe and precise treatment in the fields of endovascular treatment and neurosurgery.

Combined surgical and endovascular treatment of complex cerebrovascular diseases in the hybrid operating room

Background Although most neurovascular diseases can be treated either by microsurgical or endovascular means, a subset of patients may require a combined approach. Patient transfer from the operating room (OR) to the angiosuite has been a fundamental drawback of this type of approach. Objective The purpose of this study is to report our clinical experience performing combined surgical and endovascular procedures for neurovascular diseases in the hybrid OR. Methods 29 patients with neurovascular diseases underwent combined endovascular and surgical procedures in a single session: 16 were scheduled combined treatment and 13 were emergency combined procedures. Of the emergency cases, three were rescue surgeries after endovascular complications. Three patients had ruptured intracranial aneurysms, eight had unruptured intracranial aneurysms, eight had arteriovenous malformations and eight had arteriovenous fistulae; two patients had either a spinal tumor or dural arteriovenous fistulae. Results All combined procedures were performed in a single session without changing the patients surgical position. In cases of ruptured arteriovenous malformations or aneurysms with hematoma, an emergency embolization was performed to assist the surgical procedure. Combined superficial temporal artery–middle cerebral artery (STA–MCA) bypass followed by endovascular parent artery trapping were successfully performed for complex large or giant aneurysms. There were two periprocedural ischemic complications. Of the three patients who underwent surgical rescue after endovascular complications, two remained intact and one died despite immediate surgical procedures. Conclusion A combined endovascular and surgical approach conducted in a hybrid OR provides a new strategy for the treatment of complex neurovascular diseases.

A Case of Cerebrospinal Fluid Eosinophilia Associated with Shunt Malfunction

A 3-month-old female patient presented with a meningomyelocele at the lumber region associated with congenital hydrocephalus. She underwent ventriculoperitoneal (V-P) shunt surgery using the Sophy system. The shunt system was replaced due to a malformation. Following replacement, the patient presented with cerebrospinal fluid (CSF) eosinophilia at the age of 8 months. The eosinophilic granulocytosis of the CSF improved dramatically following systemic prednisolone administration. CSF eosinophilia without accompanying inflammation or pyrexia in the present case may have resulted from an allergic response to a foreign material such as the silicone tube pressure valve of the Sophy system or the sutures rather than bacterial or fungal infection. Based on our results, we believe that some patients may experience CSF eosinophilia following postoperative V-P shunt due to an allergic reaction to the shunt equipment. Prompt steroid treatment can produce spontaneous regression in such cases.

Vascular Orientation by Intra-arterial Dye Injection during Spinal Arteriovenous Malformation Surgery: Technical Note

OBJECTIVE Rich and complicated vascular structures on the spinal cord often interfere with obliteration of a spinal arteriovenous malformation (AVM). Vascular orientation during spinal AVM surgery is essential. The authors recently performed six consecutive spinal AVM surgeries in five patients (two with perimedullary AVMs, and three with dural arteriovenous fistulae) with the aid of intra-arterial injection of dye (indigo carmine). METHODS Two representative cases are described. A microcatheter was placed preoperatively in the artery of interest. Subsequent to the exposure of the vascular complex, a 1-ml injection of indigo carmine (2 mg/ml) clearly demonstrated the feeding arteries and the draining veins around the AVM or dural arteriovenous fistula. RESULTS One patient had repeat surgery because of incomplete obliteration of the AVM owing to migration of the catheter. All patients, except one who had temporary postoperative deterioration and persistent neurological deficits, had good surgical outcomes, however. No apparent side effects caused by the dye were reported. CONCLUSION The assistance system for spinal AVM surgery is easy and safe and can be applied in other surgical institutions.

Infected subdural hematoma

A case is presented in which Escherichia coli seeded a pre-existing chronic subdural hematoma. A 77-year-old woman was admitted to our hospital because of lethargy, left hemiparesis and fever. Drainage through a burr hole was performed with the diagnosis of bilateral chronic subdural hematoma. Operative findings revealed the infected subdural hematoma on the right side and non-infected subdural hematoma on the left side. Cultures of the subdural hematoma grew Escherichia coli. In view of the pyuria, the etiology of the infected subdural hematoma was postulated to be a urinary tract infection. In the majority of 14 reported cases, the causative organisms were Escherichia coli, Salmonella, and the systemic sources of infection included the urinary tract, gastrointestinal disease, or were unknown. The possibility of infected subdural hematoma should be considered when computed tomography findings suggestive of chronic subdural hematoma exist in a patient with signs of infection.

Determining the Presence of Thin-Walled Regions at High-Pressure Areas in Unruptured Cerebral Aneurysms by Using Computational Fluid Dynamics.

BACKGROUND Thin-walled regions (TWRs) of cerebral aneurysms are at high risk of rupture, and careful attention should be paid during surgical procedures. Despite this, an optimal imaging technique to estimate TWRs has not been established. Previously, pressure elevation at TWRs was reported with computational fluid dynamics (CFD) but not fully evaluated. OBJECTIVE To investigate the possibility of predicting aneurysmal TWRs at high-pressure areas with CFD. METHODS Fifty unruptured middle cerebral artery aneurysms were analyzed. Spatial and temporal maximum pressure (Pmax) areas were determined with a fluid-flow formula under pulsatile blood flow conditions. Intraoperatively, TWRs of aneurysm domes were identified as reddish areas relative to the healthy normal middle cerebral arteries; 5 neurosurgeons evaluated and divided these regions according to Pmax area and TWR correspondence. Pressure difference (PD) was defined as the degree of pressure elevation on the aneurysmal wall at Pmax and was calculated by subtracting the average pressure from the Pmax and dividing by the dynamic pressure at the aneurysm inlet side for normalization. RESULTS In 41 of the 50 cases (82.0%), the Pmax areas and TWRs corresponded. PD values were significantly higher in the correspondence group than in the noncorrespondence group (P = .008). A receiver-operating characteristic curve demonstrated that PD accurately predicted TWRs at Pmax areas (area under the curve, 0.764; 95% confidence interval, 0.574-0.955; cutoff value, 0.607; sensitivity, 66.7%; specificity, 82.9%). CONCLUSION A high PD may be a key parameter for predicting TWRs in unruptured cerebral aneurysms. ABBREVIATIONS CFD, computational fluid dynamicsMCA, middle cerebral arteryPave, average pressurePD, pressure differencePmax, maximum pressureTWR, thin-walled regionWSS, wall shear stress.

BRAF V600E-mutated diffuse glioma in an adult patient: a case report and review

Recent advances in genomic technology and genome-wide analysis have identified key molecular alterations that are relevant to the diagnosis and prognosis of brain tumors. Molecular information such as mutations in isocitrate dehydrogenase (IDH) genes or 1p/19q co-deletion status will be more actively incorporated into the histological classification of diffuse gliomas. BRAF V600E mutations are found frequently in circumscribed low-grade gliomas such as pleomorphic xanthoastrocytoma (PXA) and extra-cerebellar pilocytic astrocytoma, or epithelioid glioblastomas (E–GBM), a rare variant of GBM. This mutation is relatively rare in other types of diffuse gliomas, especially in adult onset cases. Here, we present an adult onset case of IDH wild-type/BRAF V600E-mutated diffuse glioma, evolving from grade III to grade IV. The tumor displayed atypical exophytic growth and had unusual histological features not fully compatible with, but indicative of PXA and E-GBM. We discuss differential diagnosis of the tumor, and review previously described diffuse gliomas with the BRAF V600E mutation.

Parallel insertion endoscopic technique for precise catheter placement in cystic craniopharyngiomas.

BACKGROUND Total removal of craniopharyngioma is the most acceptable therapeutic modality; however, there are cases in which radical excision is not possible. To reduce the cystic component volume, an Ommaya reservoir catheter can be placed endoscopically. However, there are certain complications and risks with this type of maneuver, such as misplacement of the catheter, which may result in leakage of cyst contents or installed fluids such as bleomycin. Thus, accurate placement of intracystic catheter is extremely important. PATIENTS AND METHODS The authors placed Ommaya reservoir catheters running over the outer surface of a transparent endoscopic sheath in three cases. RESULTS This neuroendoscopic procedure permits easier manipulation of the catheter and precise placement of the catheter tip. This technique was useful for placement of Ommaya reservoir catheters. CONCLUSIONS This new technique of catheter placement with neuroendoscopy is more accurate, safer, and less invasive.

Imaging alterations due to squamous metaplasia in intracranial neurenteric cysts: A report of two cases.

Intracranial neurenteric cysts are rare congenital abnormalities with a broad imaging spectrum, and therefore are occasionally mistaken for other common intracranial cysts such as epidermoid and arachnoid cysts. We report two cases of neurenteric cysts in the posterior cranial fossa that were initially mistaken for other types of cysts. They exhibited signal intensity alterations in magnetic resonance imaging with significant volume expansion during their long-term observation. Both cases received surgical treatment because of clinical deterioration. Histologically, the cysts were lined by flattened or cuboidal epithelium, occasionally showing squamous metaplasia. Xanthogranulomatous inflammation and accumulation of cholesterol clefts, dry keratin and proteinaceous substance were observed in the cysts. These findings may indicate that chronic inflammation in neurenteric cysts induces squamous metaplasia, keratinization and high proteinaceous content, and causes MRI signal intensity alterations and volume expansion. We propose that MRI signal intensity alterations in neurenteric cysts may be a warning sign of their volume expansions, and thus require closer follow-up imaging and eventually surgical treatment.

E-052 Robotic digital subtraction angiography systems within the hybrid operating room

Objective The authors describe the experience of robotic digital subtraction angiography (DSA) system in the hybrid operation room (OR) Methods A newly designed robotic DSA system (Artis zeego; Siemens AG, Erlangen, Germany) was installed in one of the hybrid OR. The system consists of a multi-axis robotic C arm and surgical OR table. In addition to conventional neuroendovascular procedures, the system was used as an intraoperative imaging tool for various neurosurgical procedures such as aneurysm clipping or spine instrumentation. Results 501 neurosurgical procedures were successfully conducted in the hybrid OR using robotic DSA. During surgical procedures such as aneurysm clipping or arteriovenous fistula treatment, intraoperative two-dimensional/three-dimensional angiography and C arm based CT images (Dyna CT) were easily performed without moving the OR table. In addition, newly developed virtual navigation software (i-guide) can be used in the frameless navigation and access to deep seated intracranial lesions or needle placement. Conclusion The newly developed robotic DSA system provides safe and precise treatment in the field of endovascular treatment and neurosurgery.