Correlations Among Consistency, Computed Tomography Values, and Histopathological Subtypes of Spinal Meningioma.

The consistency of spinal meningiomas is important to consider when performing tumor removal surgery. This study evaluated the correlations between spinal meningioma consistency and both preoperative computed tomography (CT) values and histopathological subtypes. Fifteen consecutive patients who underwent surgical resection of spinal meningioma at our institution were identified, and preoperative CT values and the signal intensity of T2-weighted magnetic resonance images of the tumor were determined retrospectively. The consistency of the spinal meningioma was defined based on the ultrasonic surgical aspirator output during tumor debulking. Patients were assigned to 2 groups: a soft group (n=4) and a hard group (n=11). The T2 signal intensity was significantly higher in the soft group than in the hard group (p=0.001). While the CT values were considerably higher in the hard group, the difference was not significant (p=0.19). Regarding the histopathological subtypes, psammomatous meningioma exhibited significantly higher CT values than meningothelial meningioma (p=0.019); however, there was a higher frequency of hard tumors in meningothelial meningioma cases than in psammomatous meningioma cases. Although neither robust correlations between tumor consistency and CT values nor a relationship between tumor consistency and histopathological subtype has been established, these results might help with the perioperative manegement of spinal tumors.

Pitfalls of skull base reconstruction in endoscopic endonasal approach.

Various skull base reconstruction techniques have been developed in endoscopic endonasal approach (EEA) for skull base lesions to prevent postoperative cerebrospinal fluid (CSF) leakage. This study was performed to evaluate the efficacy and pitfalls of our method of skull base reconstruction after EEA. A total of 123 patients who underwent EEA (127 surgeries) between October 2014 and May 2017 were reviewed. Our algorithm for skull base reconstruction in EEA was categorized based on intraoperative CSF leakage graded as follows: grade 0 was excluded from this study; grade 1, dural suturing with abdominal fat graft or packing of gelatin sponge into the cavity; grade 2, method for grade 1 with addition of mucosal flap or nasoseptal flap (NSF); and grade 3, duraplasty in fascia patchwork closure with NSF. Bony reconstruction was not mandatory, and there was no postoperative bed rest or initial lumbar drainage (LD) insertion in any of the cases. Postoperative CSF leakage after EEA was mostly prevented (96.3%) by our algorithm without postoperative initial LD or bed rest. On the other hand, reconstruction surgery was required for postoperative CSF leakage in two cases-one with prior multitranssphenoidal surgery and radiotherapy and another patient with poor compliance due to communication difficulties. Both of the latter patients were obese. Greater care with regard to postoperative CSF leakage is required in patients with prior EEA with radiotherapy and obesity. In such high-risk patients, initial LD or bed rest may be required to prevent postoperative CSF leakage. It is also important to restrict activities that result in increased intracranial pressure.

Usefulness of venous catheter as an intraluminal stent for end-to-end venous anastomosis.

BACKGROUND: Venous anastomosis is one of the most difficult techniques in vascular neurosurgery. METHOD: We present a simple technique of end-to-end venous anastomosis for reconstruction of accidentally injured vein. A venous catheter was used for the stent during the end-to-end anastomosis. RESULTS: The venous catheter as the stent facilitated confirmation of the ostium of the vein. The venous end-to-end anastomosis was successfully performed. CONCLUSIONS: Accidental venous injury can be reconstructed with the present simple technique.

Transjugular tubercle-preaccessory approach for ventrocaudally located PICA aneurysm.

BACKGROUND: Posterior inferior cerebellar artery (PICA) aneurysms are often located in the ventral craniocervical junction. Such deep-seated aneurysms are usually treated with coil embolization. However, recurred and/or very small PICA aneurysms are hardly treated with an endovascular approach. METHOD: We present a modification of the transcondylar fossa approach with intradural and extradural removal of the jugular tubercle. An adequate preaccessory surgical corridor was created with this novel technique. CONCLUSION: The ventocaudal PICA aneurysm was clipped through the outside of the spinal accessory nerve without surgical manipulation of other lower cranial nerves. This approach is worthwhile to avoid dysphagia.

Clinical characteristics of pituitary adenomas with radiological calcification.

BACKGROUND: Radiographic detection of calcification in pituitary adenoma is relatively rare, and the clinical characteristics of pituitary adenoma with calcification remain unclear. Herein, the clinical characteristics of pituitary adenoma with radiological calcification were investigated. METHODS: A total of 160 patients who underwent surgical resection of pituitary adenomas between February 2004 and December 2016 were reviewed. Eighty-one patients had hormone-secreting pituitary adenomas, and 79 patients had nonfunctioning pituitary adenoma. Among these 160 patients, cases with radiological calcifications on preoperative neuroimaging were included in this study, and clinical characteristics with intraoperative findings were analyzed, retrospectively. RESULTS: Pituitary adenoma with calcification on preoperative neuroimaging was observed in only nine cases (5.6%). The study population consisted of these nine patients with nonfunctioning pituitary adenoma (n = 5), mixed growth hormone and prolactin-secreting pituitary adenomas (n = 3), and a prolactinoma (n = 1). In 89% of cases (n = 8), calcified pituitary adenoma was soft enough for suction despite the presence of a granular gritty texture intraoperatively. Besides, in a single patient (11%), evidence of hard thick capsular calcification was seen surrounding a soft tumor component; however, it did not interfere with adequate removal of the soft part, and tumor resection was possible in all cases without any complications. CONCLUSIONS: Pituitary adenoma presenting with calcification is relatively rare, but should be kept in mind to avoid making a wrong preoperative diagnosis. As not all pituitary adenomas with calcification are hard tumors, preoperative radiological calcification should not affect decision-making regarding surgical indications.

Tailor-Made Endoscopic Surgical Strategy for Severe Intraventricular Hemorrhage with Obstructive Hydrocephalus.

BACKGROUND: Severe intraventricular hemorrhage (IVH) is associated with a high mortality rate and poor functional outcome, even with recent neurosurgical developments. IVH requires emergent surgery to save the patient's life, but the optimal surgical strategy remains controversial. We assessed the results obtained with our tailor-made endoscopic surgical strategy for severe IVH with obstructive hydrocephalus. METHODS: Consecutive patients with severe IVH owing to intracerebral hemorrhage who were treated with endoscopic surgery in the acute phase were retrospectively reviewed. Both rigid and flexible endoscopes were used for removal of hematoma in the whole ventricular system. Endoscopic third ventriculostomy and septostomy were performed as appropriate in each individual case. RESULTS: Eight patients met the inclusion criteria and were included in the analysis. Sufficient IVH removal without neglecting the fourth ventricle was achieved with our technique in 6 of 8 cases (75.0%). Endoscopic third ventriculostomy and septostomy were added in 4 cases each (50.0%). Four patients (50.0%) had a marked recovery and a good outcome (modified Rankin Scale score ≤2) despite disease severity at onset. The procedure was completed successfully in all cases, and there were no surgery-related complications. CONCLUSIONS: This study showed that our tailor-made endoscopic surgical strategy for severe IVH with obstructive hydrocephalus may be beneficial.

Acromegaly in preadolescence: A case report of a 9-year-old boy with acromegaly.

BACKGROUND: Acromegaly has been reported in adolescents and young adults, but it is unusual in preadolescence. Diagnosis and management pose different challenges in this age group. Here, we present a rare case of acromegaly in preadolescence. CASE DESCRIPTION: A 9-year-old boy presented with acromegalic features and MRI revealed a pituitary tumor. He was diagnosed as having growth hormone secreting pituitary adenoma based on the multidisciplinary assessment, and underwent gross total tumor resection through an endoscopic endonasal approach (EEA) with subsequent normalization of the hormonal parameters. CONCLUSIONS: Advances in EEA have made safe removal and cure possible even in children. However, long- term follow-up is needed in such younger patients with multidisciplinary management by neurosurgeons, endocrinologists, pediatricians, and ENT surgeons.

Superficial Siderosis Associated with Craniopharyngioma.

BACKGROUND: Superficial siderosis (SS) associated with craniopharyngioma is an extremely rare occurrence. To our knowledge, only 3 cases have been reported in literature. Two of the cases occurred following resection of the tumor. Similar to the present case, 1 of the cases was discovered before surgical intervention, "pure tumor-related" SS. The clinical presentation, diagnosis, management, and outcome are discussed in this article. CASE DESCRIPTION: A 50-year-old man presented with an 11-month history of left-sided tinnitus, hearing impairment, and a 2-month history of visual disturbance. Cerebellar ataxia and gait disturbance were found on examination. Brain magnetic resonance imaging findings were consistent with SS. Cerebrospinal fluid (CSF) analysis before surgery revealed xanthochromia confirming an existing chronic sustainable subarachnoid hemorrhage. He underwent a tumor resection in endoscopic endonasal approach followed by stereotactic radiosurgery. On follow-up, the visual symptoms resulting from craniopharyngioma subsided, whereas hearing impairment, cerebellar ataxia, and gait disturbance associated with SS did not progress but were unchanged despite subsequent evidence of watery-clear CSF. CONCLUSIONS: In the present case, SS could be associated with craniopharyngioma on the basis of CSF findings and clinical symptoms. Detection and early treatment aimed at eliminating the bleeding source offer the best chance of halting the disease process.

Cystic Lymphocytic Hypophysitis Mimicking Pituitary Apoplexy: Daunting Challenge.

BACKGROUND: Inflammatory lesions of the pituitary gland including hypophysitis are poorly understood, and it is difficult to make a correct diagnosis on the basis of only clinical and radiologic findings. CASE DESCRIPTION: An otherwise healthy 68-year-old man presented with sudden onset of headache, visual impairment, and pituitary insufficiency. Magnetic resonance imaging revealed a pituitary mass with cystic component showing changing intensity on follow-up images. Also, changing density of the lesion was demonstrated on computed tomography over a short period of time. These findings suggested a hemorrhagic lesion, and a preoperative diagnosis of pituitary apoplexy associated with a preexisting pituitary adenoma was made on the basis of clinical and radiologic findings. In the endoscopic endonasal approach for tumor resection, there was neither hematoma nor adenoma. Histopathologic diagnosis was lymphocytic hypophysitis. CONCLUSIONS: To the best of our knowledge, this is the first case report of hypophysitis with radiologic signal changes over a short period. Vigilant attention regarding the clinical diagnosis of such rare entity is paramount.

Risks of Endoscopic Temporal Ventriculocisternostomy for Isolated Lateral Ventricle: Anatomic Surgical Nuances.

BACKGROUND: Entrapment of the temporal horn, known as isolated lateral ventricle (ILV), is a rare type of noncommunicating focal hydrocephalus, and standard treatment has not been established. We report 2 cases of endoscopic surgery for ILV and highlight the anatomic surgical nuances to avoid associated surgical risks. CASE DESCRIPTION: The first patient presented with recurrent ILV following initial shunt placement for ILV, owing to shunt malfunction. In the second patient, ILV recurred secondary to choroid plexus inflammation caused by cryptococcal infection. Endoscopic temporal ventriculocisternostomy was effective in both cases. However, in the second case, the choroidal fissure was fenestrated, which led to cerebral infarction in the territory of the choroidal artery zone, attributed to damage of the branches of the choroidal segment of the anterior choroidal artery. CONCLUSIONS: Although endoscopic temporal ventriculocisternostomy is considered a safe and less invasive procedure for treatment of symptomatic ILV, the technique is still associated with risks. To avoid complications, it is necessary to be familiar with the anatomy of the choroidal arteries and the pertinent endoscopic intraventricular orientation. Additionally, sufficient experience is required before it can be recommended as the treatment of choice.

Intraoperative Evaluation of Reverse Bypass Using a Naturally Formed "Bonnet" Superficial Temporal Artery: Technical Note.

BACKGROUND: In reverse bypass that used a naturally formed "bonnet" superficial temporal artery, intraoperative volume flow measurement quantifies flow augmentation after revascularization, confirms flow preservation, and identifies inadvertent vessel compromise. CASE DESCRIPTION: A 75-year-old man presented with transient ischemic attacks attributed to right internal carotid artery stenosis. He underwent successful reverse bypass via a naturally formed "bonnet" superficial temporal artery middle cerebral artery bypass. As the result of proper intraoperative volume flow evaluation, a successful reverse bypass was achieved. CONCLUSIONS: Modification of the intraoperative stroke risk and prediction of the long-term patency after reverse bypass can be achieved by meticulous intraoperative blood flow evaluation.

Evaluation of Metallic Artifacts Caused by Nonpenetrating Titanium Clips in Postoperative Neuroimaging.

BACKGROUND: Nonpenetrating titanium clips create no suture holes and thereby reduce cerebrospinal fluid leakage after dural closure. However, no data exist regarding metallic artifacts caused by these clips during postoperative neuroimaging. We aimed to evaluate clip-related artifacts on postoperative magnetic resonance (MR) images of 17 patients who underwent spinal surgery. METHODS: A phantom study evaluated the size of metallic artifacts, and a clinical study evaluated the quality of postoperative spinal MR images. Both 1.5-T studies used T1-weighted and T2-weighted fast spin echo sequences. The phantom study compared clip and artifact size for 10 clips. Artifacts were defined as signal voids surrounded by high signal amplitude that followed the clip shape. In the clinical study, 2 neurosurgeons assessed 22 images from 17 patients of the spinal cord, cauda equina, and paravertebral muscles adjacent to the nonpenetrating titanium clips, using 5-point scales. RESULTS: Mean metallic artifact sizes were 4.82 ± 0.16 mm (T1) and 4.66 ± 0.25 mm (T2; P < 0.001 vs. control). The former and latter were respectively 207% and 200% larger than the clip size. Both readers graded spinal cord and paravertebral muscles images as 3 or 4, indicating very good image quality regardless of clip-related artifacts, with excellent interobserver agreement (κ = 0.99 and 0.98, respectively). CONCLUSIONS: Metallic artifacts caused by nonpenetrating titanium clips were 200% larger than the actual clip but did not affect spinal cord and extradural tissue visualization. The use of these clips for closing the spinal dura mater does not alter postoperative radiologic evaluation quality.

Histological Analysis of Aneurysm Wall Occluded with Clip Blades. A Case Report.

Reports on histological changes of vascular wall following clipping surgery have been scarce. The authors experienced a case of unruptured cerebral aneurysm in which the tissue occluded by clip blades for 6 years was obtained and histologically examined. The aneurysmal wall following clipping showed granulomatous inflammation with necrosis, and occluded aneurysmal walls were found with collagenous fibrous tissue. Mild infiltration by lymphocytes and fibrous thickened intima occurred.

Rescue revision techniques for end-to-side anastomosis: Technical note.

BACKGROUND: Extracranial-intracranial bypass operation is an essential procedure for cerebrovascular surgeons. Proper procedure of the bypass requires special skills, selected instruments, and training in the microsurgical laboratory. In spite of the high success rate for extracranial-intracranial bypass, a potential pitfall while performing an end-to-side anastomosis is poor blood flow or occlusion at the anastomotic site during surgery. If this happens, revision procedure is necessary. METHODS: We introduce our salvage techniques for anastomosis revision with or without recipient artery occlusion. RESULTS: With this method, ischemic complication related to revision procedure minimizes ischemic complications. CONCLUSIONS: The present technique is a simple method for anastomosis revision.