[A Case of Primary Intrasellar Chondroid Chordoma].

OBJECTIVES: Intracranial chordomas are thought to arise from remnants of the notochord and usually occur at the parasellar region. We present a case of a primary intrasellar chondroid chordoma in a patient who was initially diagnosed with a pituitary adenoma. CASE: A 77-year-old woman had a history of two surgeries for a tumor in the sella turcica(17 months after the 1st surgery). On initial MRI, the intrasellar mass showed low signal intensity on T1WI, very high signal intensity on T2WI, and inhomogeneous enhancement. On bone reconstructive CT, the sellar floor was thin, and no abnormalities were observed at the top of the clivus. Transsphenoidal surgery was performed. The pathological diagnosis was pituitary adenoma in both cases. Seventy-two months after the 1st(31 months after the 2nd)surgery, she developed right-sided oculomotor and abducent nerve palsies again. Since recurrence occurred during the relatively short period, the surgical specimens obtained from the 1st and 2nd surgeries were reexamined. Reexamination of the previously obtained specimen demonstrated areas of chondroid tissue that were embedded in a mucoid stroma and tumor cells that were composed of round or pleomorphic nuclei with vacuolated cytoplasm(physaliphorus cells)that were compatible with chondroid chordoma. The third surgery was performed. Postoperatively, her symptoms improved, and cyber knife therapy was administered for the residual part of the tumor. CONCLUSIONS: Although intrasellar chondroid chordomas are extremely rare, they should be considered in the differential diagnosis of tumors located in the sella turcica.

Surgical removal of an arteriovenous malformation in the anterior perforated substance in a pregnant woman.

BACKGROUND: A tailor-made treatment is often required in arteriovenous malformations (AVMs) depending on the individual situation. In most cases, treatment strategy is usually determined according to the patient's Spetzler-Martin grade. However, in the present case, we were not able to treat the patient following the usual guidelines because of neurological symptoms and pregnancy. CASE DESCRIPTION: We describe a rare case of a 31-year-old woman in the 15th week of gestation who presented with an AVM in the anterior perforated substance (APS). She suffered a sudden coma and hemiplegia. A computed tomographic scan showed an enhanced mass and a huge hematoma in the basal ganglia and temporal lobe. The hematoma was successfully evacuated in an endoscopic procedure. Angiography showed that a 25-mm nidus in the APS was fed by the anterior choroidal arteries (AChAs) and the lenticulostriate arteries (LSAs). Therefore, we attempted to remove the nidus because the patient became alert with mild aphasia and hemiparesis 10 days after hemorrhage. The feeding arteries were cut under motor evoked potential (MEP) monitoring, and the nidus was totally resected leaving two of four AChAs and a single artery with several LSAs. The postoperative course was uneventful, and she gave birth to a healthy baby by caesarian delivery 122 days after the hemorrhage with only minor sequelae. CONCLUSIONS: Surgical strategy with a device-administered anesthesia are suitable for removing large AVMs even in pregnant women and for the successful outcome of their pregnancies. Even after recovering from a coma and hemiplegia, MEP monitoring is effective for removing large AVMs even when located in the APS.

[A Case of Primary Extradural Meningioma Located at the High Convexity:A Case Report and Review of the Literature].

OBJECTIVES: Primary meningiomas arising outside the intracranial component are rather rare and have been termed primary extradural meningiomas(PEMs). We present a case of an intraosseous-type PEM occurring at a high convexity location and discuss the clinical characteristics of PEMs. CASE: An 80-year-old woman presented with a soft and painless subcutaneous mass of approximately 10 cm in diameter in the right parietal region, which had appeared 1 year previously. Mild cognitive dysfunction and left hemiparesis were observed upon admission. A skull radiograph and a bone window computed tomography scan revealed an osteolytic lesion at the above-mentioned site. Magnetic resonance imaging indicated that the mass was inhomogeneously enhanced and seemed to extend through the skull defect both intra- and extra-cranially. The preoperative diagnosis was a metastatic skull bone tumor due to the patient's history of breast cancer. During surgery, the tumor was found to be solid and had expanded through both the inner and outer tables of the skull, destroyed the inner table at one location, and perforated into the subdural space via the thinned, but not infiltrated, dura mater. The tumor was removed along with a wide margin of surrounding healthy bone and a cranioplasty was performed using a titanium plate. The histopathological diagnosis was atypical meningioma(World Health Organization grade II). Postoperatively, no adjuvant therapies(radiation and/or chemotherapy)were administered and the patient was reported to be well at 8 months post-surgery with no evidence of tumor recurrence. CONCLUSIONS: Although PEMs are rather rare, clinicians should consider the differential diagnosis of osteolytic skull vault tumors.

Risk Factors of Contralateral Microembolic Infarctions Related to Carotid Artery Stenting.

This study sought to analyze the incidence of contralateral microembolic infarctions (MIs) on diffusion-weighted imaging (DWI) following protected carotid artery stenting (CAS) and compared the difference of risk factors between ipsilateral and contralateral lesions. From April 2010 to March 2017, 147 CASs in 140 patients were performed. All the patients underwent DWI within 1 week before and 24 hrs after the procedures. CAS was successfully completed in 145 (98.6%) of the 147 procedures. Forty-nine (33.8%) patients with new MIs revealed on postprocedural DWI were enrolled. They were divided into ipsilateral and contralateral groups based on the side of the CAS and MIs. The ipsilateral group indicates patients with MIs exclusively on the side of CAS. The contralateral group includes patients with MIs on the opposite side of the CAS or both sides. Patients with MIs at vertebrobasilar territory were excluded. Patient characteristics, morphology of the carotid artery and aortic arch, and procedural data were retrospectively assessed and compared between the two groups. Twenty-two (15.2%) and 14 (9.7%) patients were assigned to the ipsilateral and contralateral groups, respectively. Advanced age, left-sided stenosis, severe aortic arch calcification (AAC) on chest X-ray and contralateral carotid occlusion significantly increased the occurrence of contralateral MIs. On multivariable logistic regression analysis, severe AAC was statistically more frequent in the contralateral group. In the present study, the incidences of contralateral MIs after CAS is relatively not low. Advanced aortic atherosclerosis is statistically predictive for contralateral MIs. AAC on chest X-ray is a useful finding for estimating aortic atherosclerosis in candidates for CAS.

[A Case of Multiple Atherosclerotic Fusiform Cerebral Aneurysms with Repeated Subarachnoid Hemorrhage].

Pure fusiform aneurysms without dissection are considered to have a low risk of rupture. Furthermore, aneurysm wall with atherosclerotic change tends to be less susceptible to rupture. We present a rare case of multiple atherosclerotic fusiform aneurysms associated with repeated subarachnoid hemorrhage(SAH)during a 9-year observation period. A 34-year-old woman was admitted to our hospital because of SAH. SAH with a temporal hematoma due to a fusiform aneurysm of the right middle cerebral artery(MCA)was detected using computed tomography(CT). Associated fusiform aneurysms were observed in the left posterior cerebral artery(PCA)and the left MCA. The right MCA aneurysm was occluded with angioplastic clipping. Eight years after the first onset, angioplastic clipping was performed on the other two fusiform aneurysms because of their growth. Intraoperative findings showed atherosclerotic change in the parent artery wall, similar to the right MCA aneurysms. The right MCA aneurysm ruptured again 1 year later. The aneurysm was treated with proximal occlusion combined with a bypass from the occipital artery to the distal MCA. The patient was in a stable state, although, she was disabled because of SAH damage. The effects of atherosclerotic fusiform aneurysms, which are rarely encountered, are not well known. Some studies have reported the risk of hemorrhage from these aneurysms. This case suggests the necessity of long-term follow-up for the prediction of aneurysm growth and bleeding. Moreover, proximal occlusion combined with an external bypass is better for the treatment of this type of aneurysm because angioplastic clipping is not curative.

Steroid-resistant Tolosa-Hunt syndrome with a de novo intracavernous aneurysm: A case report.

BACKGROUND: We report a case of steroid-resistant Tolosa-Hunt syndrome (THS) with recurrent bilateral painful ophthalmoplegia, accompanied with sphenoid sinusitis, pituitary abscess, and an aneurysm arising from the cavernous portion of the internal carotid artery. CASE DESCRIPTION: A 53-year-old woman suffered severe left painful ophthalmoplegia. A magnetic resonance image (MRI) revealed thickness of the left cavernous sinus (CS). Steroid was administrated under the diagnosis of THS, and the symptom transiently diminished. However, painful ophthalmoplegia fluctuated bilaterally after tapering the steroid. An MRI showed development of bilateral cavernous lesions associated with sphenoid sinusitis, pituitary abscess, and an aneurysm in the left C4 segment. Biopsy and drainage of the lesions were performed with an endoscopic transsphenoidal procedure. The histological examination showed nonspecific granulomatous inflammation. The methotrexate (MTX) was effective to reduce the CS and pituitary lesions; however, the aneurysm slightly increased and remained unchanged in size thereafter. CONCLUSIONS: To our knowledge, this is the first report of a growing de novo C4 aneurysm in THS. Surgical intervention and administration of MTX should be attempted in steroid-resistant THS. Careful observation with serial MRI and MR angiography is important to manage the complicated THS.

[Coil Embolization of a Ruptured Anterior Communicating Artery Aneurysm Forming a Pseudoaneurysm: Report of Three Cases].

The formation of an intracranial pseudoaneurysm due to a ruptured saccular aneurysm is a rare condition that exhibits characteristic angiographic findings referred to as "ghost aneurysm" or "snowman's head". Currently, no detailed information about the treatment of this condition is available. Clipping has been reported to be more effective and better for removing massive hematomas than endovascular intervention. Moreover, endovascular coil embolization during the acute phase carries a high risk of repeated aneurysm rupture due to the fragility of the pseudoaneurysmal blood clot. Here, we describe three cases of pseudoaneurysm formation following the rupture of an anterior communicating artery aneurysm, and suggest the possibility that ruptured saccular aneurysms with pseudoaneurysm formation can be treated safely and effectively with endovascular coil embolization.

Outflow occlusion with A3-A3 anastomosis for a doughnut-shaped partially thrombosed giant A2 aneurysm.

BACKGROUND: A doughnut-shaped aneurysm, which is defined as a round-shaped aneurysm composed of an intraluminar thrombus and marginal parent artery, is an extremely uncommon subtype of partially thrombosed giant aneurysms. Surgical treatment of this characteristic aneurysm is technically challenging. CASE DESCRIPTION: We report a rare case of a 79-year-old man with a symptomatic doughnut-shaped giant aneurysm at the A2 portion, which was successfully treated by outflow occlusion with an A3-A3 side-to-side anastomosis. Postoperative angiograms demonstrated no filling of the doughnut-shaped aneurysm and perfusion in the distal right anterior cerebral artery territory via the anastomosis. Follow-up magnetic resonance imaging 1 year after the surgery demonstrated significant diminution of the aneurysm. CONCLUSIONS: Outflow occlusion with distal revascularization could be an effective surgical option for such a unique aneurysm. To the best of our knowledge, this is the first report of outflow occlusion as a therapy for doughnut-shaped aneurysms.

Impact of Aneurysmal Neck Position in Endovascular Therapy for Anterior Communicating Artery Aneurysms.

Anterior communicating artery (ACoA) aneurysms have a complex architecture and many variations, making endovascular therapy more difficult in some cases. The aim of this study was to investigate whether the neck position of an aneurysm was identifiable for determining the immediate angiographic success and procedural complications in the coiling of the ACoA aneurysms. We conducted a retrospective case review of 40 patients with ACoA aneurysms treated by endovascular therapy from 2008 to 2015. The mean age was 66.8 years. Thirty-five aneurysms were ruptured; five were unruptured. For the analysis, the patients were divided into two groups according to the neck position of aneurysms: the true ACoA group, 9 patients with the neck located on the ACoA itself; and the other ACoA group, 31 patients with the neck at the junction of the A1 and A2 portions of an anterior cerebral artery. Morphological characteristics (dome size, dome direction, rate of wide neck, and angulation of aneurysms in relation to the parent artery) were analyzed along with immediate angiographic results, volume embolization ratio (VER), and procedural complications. Small aneurysms with superior dome projection and acute angulation of the aneurysm direction occurred more often in the true ACoA group. The rates of complete obliteration, VER, and procedural complications were 33.3%, 32.3%, and 22.2% in the true ACoA group and 54.8%, 36.3%, and 6.5% in the other ACoA group, respectively. True ACoA aneurysms could present an anatomical difficulty in endovascular coiling. Aneurysmal neck position should be accurately assessed to achieve successful embolization of the ACoA aneurysms.

The "temporary caging" technique for catheter navigation in patients with intracranial wide-necked aneurysms.

Endovascular treatment of wide-necked aneurysms with preservation of the parent artery remains a challenge. The authors describe a novel and simple technique to navigate a balloon or stent-delivery catheter across a wide-necked aneurysm in which previously existing methods could have failed to pass the catheter across the neck of the aneurysm, which we have named "temporary caging" technique. The technical results using this method are presented in 6 cases.

[Dural cavernous angioma:a case report and review of the literature].

Here, we report a case of dural cavernous angioma. A 54-year-old man presented with headache in his right frontal area for the previous few weeks. Computed tomography (CT) and magnetic resonance imaging revealed a well-demarcated extramedullary mass, 3 x 2.5cm in size, within the subdural space at the right frontal region. The mass was not enhanced on a contrast-enhanced CT scan, and heterogeneously enhanced after administration of Gd-DTPA on magnetic resonance images. Cerebral angiography revealed an avascular mass. Right frontal craniotomy was performed. On surgery, the mass was found to be mainly extramedullar, and partially intramedullar. No adhesion between the mass and the overlying dura was observed. It was removed in an en bloc fashion. The pathological diagnosis was cavernous angioma. The patient's headache was resolved soon after surgery. Cavernous angiomas are usually intramedullar in the subcortical white matter of the cerebral hemispheres;extramedullary cavernous angiomas are rare. Extramedullary dural cavernous angiomas located in the subdural space at the cerebral convexity are extremely rare. They usually present with headache or mass signs, and resemble meningioma radiologically. During surgery they are easily resected with minimal blood loss. Dural cavernous angiomas should be considered in the differential diagnosis of intradural extramedullary mass at the cerebral convexity.

Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm.

A 79-year-old woman presented with a subarachnoid hemorrhage. Angiography revealed pseudoaneurysm formation due to rupture of a true saccular anterior communicating artery aneurysm. Coil embolization, limited to the true aneurysm, was performed successfully with a favorable clinical outcome. This procedure can be considered as an alternative treatment option for similar aneurysms in cases where surgical clipping is contraindicated.

Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm.

A 79-year-old woman presented with a subarachnoid hemorrhage. Angiography revealed pseudoaneurysm formation due to rupture of a true saccular anterior communicating artery aneurysm. Coil embolization, limited to the true aneurysm, was performed successfully with a favorable clinical outcome. This procedure can be considered as an alternative treatment option for similar aneurysms in cases where surgical clipping is contraindicated.

Cerebral and subdural abscess with spatio-temporal multiplicity 12 years after initial craniotomy for acute subdural hematoma. Case report.

A 34-year-old man presented with a case of subdural empyema and cerebral abscess that developed 12 years after initial neurosurgical intervention for a traffic accident in 1998. Under a diagnosis of acute subdural hematoma and cerebral contusion, several neurosurgical procedures were performed at another hospital, including hematoma removal by craniotomy, external decompression, duraplasty, and cranioplasty. The patient experienced an epileptic seizure, and was referred to our hospital in March 2010. Magnetic resonance imaging revealed a cerebral abscess extending to the subdural space just under the previous surgical field. Surgical intervention was refused and antimicrobial treatment was initiated, but proved ineffective. Surgical removal of artificial dura and cranium with subdural empyema, and resection of a cerebral abscess were performed on May 12, 2010. No organism was recovered from the surgical samples. Meropenem and vancomycin were selected as perioperative antimicrobial agents. No recurrence of infection has been observed. Postneurosurgical subdural empyema and cerebral abscess are recently emerging problems. Infections of neurosurgical sites containing implanted materials occur in 6% of cases, usually within several months of the surgery. Subdural empyema and cerebral abscess developing 12 years after neurosurgical interventions are extremely rare. The long-term clinical course suggests less pathogenic organisms as a cause of infection, and further investigations to develop appropriate antimicrobial selection and adequate duration of antimicrobial administration for these cases are needed.

[A case of post-operative cerebral abscess caused by multidrug-resistant Acinetobacter baumannii-possibly originating abroad, and poorly susceptible to colistin].

We report a case of post-neurosurgical meningitis, subdural empyema, and cerebral abscess caused by multidrug-resistant Acinetobacter baumannii (MRAB) poorly susceptible to colistin. A 49-year-old man was transferred to our hospital after surgical treatment for putaminal hemorrhage in a foreign country hospital. Several examinations revealed surgical site infection (SSI). From cerebro-spinal fluid examination via ventricular drainage, MRAB was recovered. The minimum inhibitory concentration (MIC) of colistin was 2 µg/mL. Intravenous administration of colistin with ceftazidime and rifampicin was started, with intrathecal colistin administration, based on the results of a Break-point Checkerboard examination, and resulted in effective infection control. Nosocomial infection by MRAB has become an emergent problem in many countries. In Japan, several outbreak accidents caused by MRAB have been reported so far. In this case, genetic analysis revealed that the pathogen had originated from a foreign country, and the prevalence of colistin-resistant pathogens has also increased in these countries. Besides adequate isolation precautions, strategies for post-neurosurgical SSI management and establishment of effective treatments are necessary against neurosurgical SSIs caused by colistin-resistant MRAB.

A case of meningitis due to Neisseria subflava after ventriculostomy.

Surgical site infection (SSI) is an emerging problem in all fields of surgery, as well as in neurosurgery, with numerous strategies against SSI initiated in many countries. In this report, we describe a case of SSI caused by Neisseria subflava a month after ventriculostomy placement for acute hydrocephalus. A 53-year old man was referred to our hospital, and was diagnosed with a thalamic hemorrhage with ventricular rupture. Bilateral ventriculostomies were performed on the day of presentation. After intensive care for the acute stage, an SSI at the left ventriculostomy site was recognized on the 39th hospital day. The installed reservoir and ventricular tube was removed on the 40th hospital day. The CSF cell count was 2064/3, and N. subflava was recovered from the CSF culture. N. subflava is a common inhabitant found in the human upper respiratory tract, and is reported to be a rare cause of meningitis. There is one case report of meningitis caused by N. subflava transmitted during myelography from medical staff who did not wear facemasks during the procedure. Meningitis caused by N. subflava is rare, and transmission via a medical procedure is extremely rare. Although reported to be only rarely pathogenic, we must recognize that N. subflava can indeed be pathogenic, and can in rare cases be the cause of postoperative meningitis.

[A complicated case of Nocardia brain abscess for differential diagnosis].

BACKGROUND: Nocardia brain abscess is rare and has uncertain clinical features. Radiological differential diagnosis based on the metabolic feature of Nocardia is discussed. CASE DESCRIPTION: A 73-year-old man presented with a history of otitis media and was treated with antibiotics for 2 weeks. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated an irregular ring-enhancement mass in the left cerebellar hemisphere. This lesion presented as a homogeneous high-intensity area in diffusion-weighted MRI. We also found decreased N-acetyl-aspartate (NAA) peak and increased choline and lipid peaks in proton MR spectroscopy (1H-MRS). We performed an aspiration. Nocardia asiatica in the mass lesion was found by genetic analysis. The patient was treated with a sulfamethoxazole/trimethoprim (ST) mixture and minocycline (MINO) intravenously for 6 months. There has been no recurrence for 2 years. CONCLUSIONS: To our knowledge, this case is the first case of Nocardia asiatica brain abscess in Japan. We considered these MRS findings to be compatible with Nocardia brain abscess as mainly observed in aerobic metabolism. But we also detected a lactate peak in the abscess. Further research is required.