Technique for Recanalization of Sheath Introducer Occlusion due to Captured Thrombus during Mechanical Thrombectomy for Acute Ischemic Stroke: A Technical Note.

Objective: Mechanical thrombectomy (MT) is the gold standard treatment for acute ischemic stroke. During these interventions, a thrombus frequently obstructs a guiding catheter. The obstructed guiding catheter should be withdrawn before distal embolism occurs; however, albeit infrequently, the thrombus occludes even a sheath introducer (SI). While conventionally new SI placement is required for continuation of treatment, we propose a viable alternative for recanalization of the occluded SI, termed vacuum-assisted delivery of thrombus (VADT), with a clinical report of our cases. The usefulness of this technique was also evaluated in simulation experiments. Case Presentations: The VADT procedure is as follows: 1) insert a peel-away sheath, originally attached to a balloon-guiding catheter (BGC), into the SI to continuously open the hemostatic valve; 2) advance the BGC into the peel-away sheath while applying mechanical aspiration; and 3) remove the peel-away sheath/BGC assembly slowly. In a simulation environment using an artificial thrombus, we repeated the VADT procedure five times and reproducibly achieved SI reopening within only 10-20 seconds. From March 2013 to September 2022, 204 patients were treated with MT at our stroke center and SI occlusion occurred in three patients (1.5%). These events occurred exclusively in patients with extracranial internal carotid artery occlusion. All three patients with SI occlusion underwent successfully thrombus extraction in the SI using the VADT on the first try. Conclusion: The results of clinical experience and simulation experiments strongly support VADT as a reliable option for recanalization of an occluded SI.

An anomalous hyperplastic anterior choroidal artery associated with an unruptured internal carotid-posterior communicating artery aneurysm.

The anterior choroidal artery (AChA) injuries can result in severe neurologic deficits, so requiring careful observation to avoid inadvertent damage during neuroendovascular procedures. In this case report, we present the unusual case of an anomalous hyperplastic AChA associated with a fetal-type posterior communicating artery (PCoA), and an unruptured internal carotid artery (ICA) -PCoA aneurysm. A 54-year-old woman presented with persistent headache. Brain magnetic resonance imaging (MRI) showed an unruptured cerebral aneurysm in the right ICA, and cerebral angiography revealed a proximal fetal-type PComA and a distal anomalous hyperplastic AChA. Coil embolization was performed with no neurologic deficits and the target lesion was embolized with a total of 6 coils. An anomalous hyperplastic AchA has a lengthy course with numerous choroidal and perforating branches, and therefore, an abundant perfusion region. Thorough knowledge of the development and anatomy of anomalous arteries is important for safely performing endovascular procedures without causing any ischemic complications.

Efficacy of transcutaneous cardiac pacing for transient asystole caused by trigeminocardiac reflex: illustrative case.

BACKGROUND: Trigeminocardiac reflex (TCR) is a brainstem reflex caused by stimulation of the trigeminal nerve, which results in bradycardia, hypotension, and asystole. TCR can occur during any neurosurgical procedure. Initially, it is managed via the immediate removal of the stimulus from the trigeminal nerve. If asystole persists after intravenous atropine or glycopyrrolate, chest compression or transcutaneous cardiac pacing may be considered. The authors present the first case of TCR that was successfully managed with transcutaneous cardiac pacing. OBSERVATIONS: A 51-year-old man presented with aneurysmal subarachnoid hemorrhage. Although he had no history of cardiac disease and there were no abnormal findings on electrocardiography, transient asystole due to TCR occurred during craniotomy. The patient's heart rate spontaneously recovered after the immediate discontinuation of the procedure. The authors completed aneurysm clipping with transcutaneous cardiac pacing because intravenous atropine was not effective in preventing TCR. There were no complications associated with intraoperative asystole or transcutaneous cardiac pacing, and the patient was discharged without neurological deficits. LESSONS: TCR can be appropriately managed with the immediate discontinuation of intraoperative procedures. Furthermore, transcutaneous cardiac pacing may be considered for persistent TCR with poor response to intravenous atropine or glycopyrrolate.

Computed three-dimensional atlas of subthalamic nucleus and its adjacent structures for deep brain stimulation in Parkinson's disease.

Background. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is one of the standard surgical treatments for advanced Parkinson's disease. However, it has been difficult to accurately localize the stimulated contact area of the electrode in the subthalamic nucleus and its adjacent structures using a two-dimensional atlas. The goal of this study is to verify the real and detailed localization of stimulated contact of the DBS electrode therapeutically inserted into the STN and its adjacent structures using a novel computed three-dimensional atlas built by a personal computer. Method. A three-dimensional atlas of the STN and its adjacent structures (3D-Subthalamus atlas) was elaborated on the basis of sagittal slices from the Schaltenbrand and Wahren stereotactic atlas on a personal computer utilizing a commercial software. The electrode inserted into the STN and its adjacent structures was superimposed on our 3D-Subthalamus atlas based on intraoperative third ventriculography in 11 cases. Findings. Accurate localization of the DBS electrode was identified using the 3D-Subthalamus atlas, and its clinical efficacy of the electrode stimulation was investigated in all 11 cases. Conclusion. This study demonstrates that the 3D-Subthalamus atlas is a useful tool for understanding the morphology of deep brain structures and for the precise anatomical position findings of the stimulated contact of a DBS electrode. The clinical analysis using the 3D atlas supports the contention that the stimulation of structures adjacent to the STN, particularly the zona incerta or the field of Forel H, is as effective as the stimulation of the STN itself for the treatment of advanced Parkinson's disease.

Use of 5-aminolevulinic acid for the confirmation of deep-seated brain tumors during stereotactic biopsy. Report of 2 cases.

5-Aminolevulinic acid (ALA) has been successfully used to confirm the target tumor tissues obtained during stereotactic biopsy. The authors report their experience with 2 patients who underwent stereotactic biopsies of thalamic malignant lymphoma and pontine glioma utilizing 5-ALA. Intraoperatively, the tumor specimens fluoresced, allowing for confirmation that the obtained target specimen contained tumor tissues. No serious side effects or complications occurred.

Extended transsphenoidal surgery for suprasellar craniopharyngiomas: infrachiasmatic radical resection combined with or without a suprachiasmatic trans-lamina terminalis approach.

BACKGROUND: An extended transsphenoidal approach allowed for direct midline exposure of the parasellar structures such as the hypothalamic-pituitary axis and the third ventricle. To evaluate the capability of this approach for removal of suprasellar craniopharyngiomas, surgical outcomes were retrospectively analyzed. METHODS: During a 9-year period, 20 consecutive patients with suprasellar craniopharyngioma underwent transsphenoidal tumor resection. The average follow-up period was 55 months. No patient had a purely intrasellar tumor, 9 had prechiasmatic tumors, 9 had retrochiasmatic tumors, and 2 had purely intraventricular tumors. RESULTS: Total resection was achieved in 86% of operations. Even in mostly intraventricular cases, a transsphenoidal trans-lamina terminalis approach afforded complete resection. Visual improvement and preservation of the pituitary stalk were achieved in 84% and 95% of cases, respectively. New postoperative deterioration of pituitary function occurred in about 65% of cases, and no patient resolved their preoperative hormonal disturbance after surgery. The overall percentage of patients with diabetes insipidus increased to 61% postoperatively from 11% preoperatively. Nonendocrinologic surgical complications were observed: worsening of vision in 3 patients, hyperphagia in 3 patients, short-term memory loss in 2 patients, and cerebrospinal fluid leakage in 3 patients. Recurrence after total resection occurred in 2 (11%) patients with retrochiasmatic tumors. CONCLUSIONS: Reasonable surgical results in this study suggest that the extended transsphenoidal approach is safe and effective for removal of craniopharyngiomas. Although preservation of the pituitary stalk can be achieved in a high percentage of patients, postoperative endocrinopathy still remains as a significant problem after radical removal of the craniopharyngioma.

A case of lymphomatoid granulomatosis followed for 14 months on the basis of clinical and histological findings.

Lymphomatoid granulomatosis (LYG) is a systemic granulomatous disease characterized by B-cell proliferation of uncertain malignant potential. It most frequently affects the lungs but also occasionally affects the central nervous system. Its pathophysiology is unclear in numerous respects, thus making it difficult to diagnose and treat. We recently encountered a case of LYG that was followed clinically and histologically for 14 months. A 55-year-old man was hospitalized with multiple brain tumors for which the final diagnosis was not made until the second surgery, 14 months after the first intervention. Following the diagnosis, he was treated with steroid pulse therapy. At present, 3.5 years after the onset of LYG, the patient is in good condition with no signs of tumor recurrence. Although LYG is usually graded on the basis of histological findings, this patient showed no histological changes or any increase in disease grade during the 14-month follow-up period.

Extended transsphenoidal approach for surgical management of pituitary adenomas invading the cavernous sinus.

OBJECTIVES: The authors devised an extended transsphenoidal approach involving a submucosal posterior ethmoidectomy that allows for adequate exposure of the cavernous sinus. To evaluate the adequacy of this approach for removal of adenomas invading the cavernous sinus, the authors retrospectively analyzed the surgical outcomes obtained in treated patients. METHODS: During a 9-year period, 36 patients with pituitary adenomas extending into the cavernous sinus underwent tumor removal at Kinki University Hospital. In the authors' technique of extended transsphenoidal surgery, the inferior wall of the affected cavernous sinus was entirely exposed, not only to permit safe removal of the tumor but also to secure the petrous portion of the internal carotid artery (ICA). For prevention of intraoperative injury to the cranial nerves, a low-profile pressure sensor was attached on the eyelid to detect eye movements in response to electrical stimulation of the cranial nerves. RESULTS: Total or subtotal tumor removal was achieved in 72% of 36 patients. In eight (67%) of 12 patients with growth hormone-secreting adenomas, hormonal remission was achieved postoperatively. Postoperative transient double vision was observed in 27% of the patients, but no serious complications, such as permanent cranial nerve palsy or ICA injury, occurred. CONCLUSIONS: These reasonable surgical results obtained in the present series of patients suggest that the extended transsphenoidal approach is safe and effective for removal of adenomas within the cavernous sinus. These preliminary results may lead to a reevaluation of the role of surgery as the therapeutic strategy for invasive pituitary adenomas.

Early effects of boron neutron capture therapy on rat glioma models.

Early effects of boron neutron capture therapy (BNCT) on malignant glioma are characterized by reduction of the enhancement area and regression of the peritumoral edema radiologically. The aim of this study was to investigate the early histological changes of tumors and inflammatory cells after BNCT in the rat brain. Rats were treated with BNCT using boronophenylalanine (BPA) 7 days after implantation of C6 glioma cells. The tumors were assessed with magnetic resonance imaging and histopathological examination at 4 days after BNCT. The mean tumor volumes were 39 +/- 2 mm3 in the BNCT group and 134 +/- 18 mm3 in the control group. In the BNCT group, tumor cells showed a less pleomorphic appearance with atypical nuclei and mitotic figures. The Ki-67 labeling index was 6.5% +/- 4.7% in the BNCT and 35% +/- 3.8% in the control group. The reactions of the inflammatory cells were examined with ED-1 as macrophage marker and OX42 as microglia marker. ED-1- and OX-42-positive cells were reduced both in the core and the marginal area of the tumor in the BNCT group. It is suggested that BNCT reduced tumor progression by suppression of proliferation. Inhibition of the activated macrophages may relate to reduced peritumoral edema in the early phase.

Icing and multilayering technique of injectable hydroxyapatite cement paste for cranial base reconstruction after transsphenoidal surgery: technical note.

OBJECTIVE: Injectable hydroxyapatite cement (HAC, Biopex; Mitsubishi Pharma Corp., Osaka, Japan) can reconstruct the accurate contour of bone defects intraoperatively, and it is slowly replaced with bone by a process of resorption and osteoconduction, making it a useful substrate for the repair of cranial defects. In the operative site with continuous oozing of the cerebrospinal fluid, however, the implanted HAC may be dissolved and washed out as a result of its water solubility during the setting time. For successful reconstruction of cranial defects in such wet situations, we describe a new technique to reinforce the implanted HAC with a multilayered application. METHODS: As a preliminary experiment, we observed that the setting process of the HAC was severely restricted by the environmental temperature. At a temperature of 5 degrees C, the initial setting time of the HAC could be extended to 10 hours after the beginning of the mixing of the HAC. Bone defects of the sellar floor after transsphenoidal surgery for pituitary adenomas, craniopharyngiomas, meningiomas, or suprasellar arachnoid cysts were reconstructed using the HAC in 55 patients during a 5-year period. The results and complications were obtained through retrospective review. RESULTS: Ninety-eight percent of bone defects were successfully repaired using the HAC, and the reconstruction remained stable over the course of this study. There was one case of postoperative cerebrospinal fluid leakage. Wound infection occurred in one patient, which required reoperation and removal of the biomaterial. CONCLUSION: The icing and multilayering method for proper use of this biomaterial resulted in restoration of the integrity of the cranial base bone and a decrease of cerebrospinal fluid leakage as a postoperative complication of transsphenoidal surgery. HAC is a biomaterial that is recommended to be used as the primary method for reconstructing cranial base bone defects.

[Effects of deep brain stimulation on urodynamic findings in patients with Parkinson's disease].

Electric stimulation therapy is one of the surgical treatments for Parkinson's disease whereby a chronic stimulating electrode is placed on the subthalmic nucleus (STN). Because medical treatments centered around L-dopa have limitations in severe Parkinson's disease, electric stimulation therapy is regarded as an appropriate treatment modality. Most Parkinson's disease patients experience lower urinary tract disorders such as urgency, daytime frequency or nocturia, due to detrusor overactivity. We conducted an International Prostate Symptom Score (IPSS) analysis and a pressure flow study (PFS) on 6 patients before and after a chronic stimulating electrode was placed on the STN and evaluated how the subjective symptoms and bladder functions changed. As a result, the IPSS total value, involuntary detrusor contraction threshold volume and maximum bladder capacity were all found to significantly improve (P<0.05). The average IPSS decreased from 11.2 to 7.0. The average involuntary detrusor contraction threshold volume increased from 90.7 ml to 172.7 ml. The average maximal bladder capacity increased from 104.0 ml to 177.2 ml. These findings suggest that the STN the positively contributes to an improvement in urinary function.

Postoperative improvement in visual function in patients with tuberculum sellae meningiomas: results of the extended transsphenoidal and transcranial approaches.

OBJECT: Recently, extended transsphenoidal surgery (ETSS) has become an alternative to transcranial surgery (TCS) for suprasellar meningiomas, although the relative benefits of ETSS have yet to be established. To evaluate the effectiveness of ETSS, the authors analyzed surgical outcomes of TCS and ETSS. METHODS: During a 12-year period, 28 patients with meningiomas arising from the tuberculum sellae underwent tumor removal at Kinki University Hospital. The first 12 patients underwent TCS, and the remaining 16 underwent ETSS. In the TCS group, the optic canal on the approach side was unroofed in all cases. In the ETSS group bilateral optic canals were opened, and the dural and bone defects of the skull base were repaired using abdominal fascia and hydroxyapatite cement. In half of the cases, lumbar drainage of cerebrospinal fluid (CSF) was also performed. RESULTS: In a retrospective analysis of this consecutive series of patients, improvement in visual acuity and intraoperative blood loss were significantly better in the ETSS group (p = 0.010 and p = 0.011, respectively), whereas improvement in visual field defects, operative times, and the tumor removal rate were not significantly different between the two groups. Nonvisual surgical complications such as CSF leakage (one patient) and infarction of a perforating artery (three patients) were observed in the TCS group. In the ETSS group, CSF leakage (two patients), anosmia (two patients), and infarction of a perforating artery (two patients) were observed. CONCLUSIONS: Given the encouraging results in improvement in visual acuity, ETSS may be acceptable for the treatment of tuberculum sellae meningiomas.

An adjustable nasal speculum for the extended transsphenoidal approach. Technical note.

The authors describe a newly modified nasal speculum that enables panoramic visualization of the deep and wide surgical field created via an extended transsphenoidal approach. In their approach, the bone around the piriform aperture is not removed.

Cervical myelopathy caused by dropped head syndrome. Case report and review of the literature.

The authors present a rare case of cervical myelopathy caused by dropped head syndrome. This 68-year-old woman presented with her head hanging forward. After 1 month, she was admitted to the medical service because of head drop progression. Examination of biopsy specimens from her cervical paraspinal muscles showed nonspecific myopathic features without inflammation, and isolated neck extensor myopathy was diagnosed. The patient's condition did not respond to the administration of corticosteroids. During follow up as an outpatient, the patient's head drop continued to gradually progress. At 1 year after onset, she developed bilateral weakness of the upper and lower extremities, clumsiness of the hands, and gait disturbance. A radiograph of the cervical spine obtained in a standing position showed a pronounced kyphotic deformity and instability at the level of C4-5. Magnetic resonance imaging demonstrated spinal cord compression at C-3 and C-4. The patient underwent a C3-4 laminectomy and occipitocervicothoracic fixation. Gait and hand coordination gradually improved, and she was able to walk with no support 1 month postoperatively. Surgical fixation was beneficial in this patient with dropped head syndrome, myelopathy, and cervical instability.

Extended transsphenoidal approach to anterior communicating artery aneurysm: aneurysm incidentally identified during macroadenoma resection: technical case report.

OBJECTIVE: Full exposure of an aneurysm and surrounding structures with minimal brain retraction is important to eliminate the aneurysm safely and accurately. We describe an extended transsphenoidal approach for clipping an anterior communicating artery (ACoA) aneurysm. CLINICAL PRESENTATION: A 58-year-old woman had a surgical history significant for subtotal removal of a macroadenoma via the posterior portion of the planum sphenoidale using an extended transsphenoidal approach. INTERVENTION: During the tumor removal, a small unruptured ACoA aneurysm was incidentally found. The aneurysm was eliminated through the same operative route under a direct and wide view. The dural window was patched with abdominal fascia and sutured with 5-0 nylon in a watertight fashion. CONCLUSION: The extended transsphenoidal approach could expose an ACoA complex and aneurysm without substantial brain retraction. If the major limitations of this approach (e.g., postoperative cerebrospinal fluid leakage and meningitis) can be overcome using technical advances, this technique will offer a minimally invasive approach to the ACoA complex.

[Surgical treatment for cerebrospinal fluid rhinorrhea from plaum sphenoidale].

A transcranial approach is frequently employed for the closure of cerebrospinal fluid (CSF) rhinorrhea, occurring after skullbase surgery or associated with anterior skull base fracture. However, the site of CSF rhinorrhea is usually most distant from the site of craniotomy and, because securing of an adequate operative field is difficult, elimination of this type of CSF rhinorrhea tends to be insufficient. We have attempted to reconstruct the anatomical structures with an extended transsphenoidal approach for a case with CSF rhinorrhea from the planum sphenoidale, and have succeeded in achieving a more physiological and reliable elimination of CSF rhinorrhea. This technique is presented, with a representative example.

Successful long-term deep brain stimulation for hemichorea-hemiballism in a patient with diabetes. Case report.

The authors report a case of hemichorea-hemiballism (HC-HB) that was successfully treated using deep brain stimulation (DBS). A 65-year-old right-handed man exhibited a sudden onset of right HC-HB without a diabetic coma. At admission T1-weighted magnetic resonance (MR) images revealed a high-intensity signal in the left striatum, contralateral to the patient's involuntary movements. The HC-HB continued for 5 months after onset of the condition despite medical treatment and a decreased intensity of the signal on T1-weighted MR images. The patient underwent placement of a quadripolar DBS electrode in the left thalamus, including the left ventral oralis (VO) anterior and posterior nuclei (the VO complex). Postoperatively, the right-sided HC-HB disappeared rapidly during electrical stimulation and there were no neurological deficits. The authors demonstrate that DBS can be an effective treatment for medically refractory HC-HB. This is the first case of HC-HB that has been successfully treated with DBS.

[Three-dimensional atlas of subthalamic nucleus and its adjacent structures].

The deep brain stimulation (DBS) is an effective treatment modality of the functional neurosurgery for disorders such as Parkinson's disease, essential tremor and generalized dystonia. Recently, the targets of DBS for treatment of Parkinson's disease are the thalamus, the Globus pallidus and subthalamic nucleus (STN). The STN-DBS induces improvements in axial motor fluctuation and the on-off phenomenon. The important problem for STN-DBS is that DBS is inserted properly into the STN for good results. The STN is a small body in the deep brain structures. We cannot understand the STN clearly because of its small size and complex shape. The topographical information of deep brain structures has been essential for accurate stereotactic placement of the stimulating electrode of DBS. The target of a deep brain structure is based on the Schaltenbrand and Wahren atlas (S-W atlas). The S-W atlas consists of two-dimensional images such as a coronal section. For this reason, it is difficult to understand localization and the shape of deep brain structures spatially, especially of the subthalamic nucleus on S-W atlas. The three-dimensional image is a useful tool for diagnosis and preoperative planning, because it can easily give neurosurgeons the vivid spatial image of complex structures. We studied a practical use of a three-dimensional atlas of deep brain structures in functional neurosurgery. We devised a three-dimensional atlas to see an image at a free angle on a personal computer. It provided us with more useful information about structures than ones by two-dimentional images. Three-dimensional atlas also helped us make a decision for placement of the deep brain electrode and appropriate electrophysiological recording.

Development of hybrid integrated endoscope-holder system for endoscopic microneurosurgery.

OBJECTIVE: Endoscopic techniques in the field of neurosurgery are under development. To perform sophisticated bimanual procedures in the delicate surgical fields of neurosurgery, rigid endoscope fixation devices with accurate locking and a safe releasing system are required. Here, we report the development of a new hybrid integrated endoscope-holder system. INSTRUMENTATION: The basic concepts of the holding device were as follows: 1) it should combine both video system and holding device; 2) it should have easy maneuverability and accurate fixation and be equipped with a safe releasing mechanism; and 3) it should be able to be used universally either in a primary or an assisting endoscopic procedure. A negatively actuated air-locking system and a bayonet-shaped endoscope were newly developed. Clinical trials of 25 patients were performed, and each prototype was tested and modified until the functional requirements were fulfilled. The final version was tested for accuracy and security in fixation and releasing mechanism. RESULTS: Eight problems were encountered in the clinical trials and improved. Accuracy in fixation of the final version was superior to the most advanced endoscope-holder on the market. No dangerous events were observed during repetitive insertion, fixation, and release in the simulated deep surgical field in the cadaveric skull. No apparent complications were noted in the clinical application. CONCLUSION: We have developed a highly reliable, accurately fixable, and easily maneuverable hybrid endoscope-holder system. To achieve a safer, more accurate, and less invasive surgery in the current socioeconomic demands, commercial manufacturers and surgeons in multiple centers need to combine their efforts to create useful techniques.