Intracranial Aneurysm Model for Detachable Coil Testing.

Intracranial aneurysm is major vascular disease which is life-threatening and challenging treatment. Detachable coil is one of the standard treatments. Because of little knowledge about it, the detachable coils were evaluated by various methods. Animal aneurysm models were also used to test this equipment. In the present study, sidewall aneurysms were created on common carotid arteries of Landrace-Yorkshire-Durocswine. External jugular vein grafts were used as aneurysm sac. End-to-side anastomosis was done. Ten aneurysms were created successfully in 5 swine. There is no perioperative death. This animal aneurysm model is appropriated for coil testing especially in the histopathology aspect.

[Case Report of Cerebellar Vermis Arteriovenous Malformation Presenting with Hydrocephalus due to Aqueductal Stenosis].

A 56-year-old man complained of gait disturbance and confused thinking. Magnetic resonance imaging(MRI)revealed an arteriovenous malformation(AVM)of the cerebellar vermis(Spetzler-Martin grade IV)causing hydrocephalus. One dilated precentral cerebellar vein was compressing the aqueduct. After feeder embolization over 3 sessions using N-butyl cyanoacrylate(NBCA), the nidus was reduced to one-third in size. However, symptoms remained unimproved, and endoscopic third ventriculostomy(ETV)was performed. The third ventricle showed thinning of the floor, with a fenestration in part of the floor. Radiological findings and clinical symptoms improved, and the patient returned home after rehabilitation. The condition of the patient remained stable as of six months later. On angiography, the draining vein showed a pressure of 20 mmHg with no change in the residual AVM. Embolization alone achieved a reduction in nidus volume, but could not reduce venous pressure, and combination therapy including ETV proved necessary. Cases with hydrocephalus due to aqueductal stenosis by AVM are extremely rare. This pathology is discussed with reference to the literature.

Evaluation for Vertebral Artery Injury with Cervical Dislocated Fracture and Optimal Treatment before Reduction.

Objective: Cervical dislocated fractures frequently cause vertebral artery injury (VAI), which, in turn, propagates the thrombus at the site of injury. Cerebral embolism due to a thrombus after the reduction of dislocation leads to a poorer neurological outcome. Therefore, we investigated the outcome of treatment for cervical dislocated fractures and the usefulness of parent artery occlusion (PAO) before reduction. Methods: Eight patients with cervical dislocated fractures with a locked facets treated at our hospital between January 2018 and December 2020 were evaluated. We retrospectively examined patient characteristics and clinical outcomes. Results: Among the eight patients, two were injured at C4/5, four at C5/6, and two at C6/7. All patients had locked facets. Four patients had bilateral dislocation, while the others had unilateral dislocation. Two patients with unilateral dislocation had ipsilateral vertebral artery occlusion (VAO), while the other six did not. Both patients with VAO underwent PAO to prevent cerebral embolism before reduction. The six patients who did not have VAI underwent reduction without preprocedural treatment. No cerebral ischemic complications were observed. One patient died due to paralysis of the respiratory muscles caused by spinal cord injury but the remaining seven recovered well. Conclusion: PAO before reduction for cervical dislocated fractures with VAO may be effective in preventing cerebral embolism after reduction.

Efficacy of Monitoring for Multiple Antiplatelet Therapy during Intracranial Stent Placement: A Preliminary Study.

Objective: During cerebral aneurysm embolization using intracranial stents, platelet aggregation increases owing to increased wall shear stress and a loss of vascular endothelial function at the stent implantation site. Preoperative multiple antiplatelet therapy was introduced to prevent severe thromboembolic complications due to increased platelet aggregation. However, specific guidelines for the administration and pharmacological evaluation of this therapy do not exist currently. We examined the benefits of perioperative platelet aggregation monitoring in a cohort of patients. Methods: We had 377 patients with unruptured intracranial aneurysms who underwent stent-assisted embolization at our hospital between December 2012 and November 2019. We ultimately included 181 patients in our final analysis. These patients were continuously administered aspirin (100 mg/day) and clopidogrel (75 mg/day) for more than 5 days before the procedure to the post-procedural period. Of these patients, 30 patients who underwent light transmission aggregometry (LTA) before procedure, post-procedure (3 days after procedure), and at first post-discharge clinic visit were included as the subjects. The following characteristics were studied: age; sex; presence/absence of hypertension, dyslipidemia, and/or diabetes mellitus; location of aneurysm; type/number of stent; technique for stent placement; duration of preoperative multiple antiplatelet therapy; perioperative platelet aggregation test results; and postoperative ischemic or hemorrhagic complications. Results: Among these 30 patients, the median duration of antiplatelet therapy prior to the preoperative platelet aggregation measurements was 7 (interquartile range [IQR]: 6-8) days, and post-discharge measurement of LTA was performed at a median period of 27 (IQR: 22-35.5) days after procedure. The preoperative, postoperative, and first post-discharge clinic visit LTA values for adenosine diphosphate (ADP)-induced platelet aggregation were 50% (IQR: 44-54%), 42.5% (IQR: 36-48%), and 36% (IQR: 32-40%), respectively. These results represented gradual decrease in LTA values and a significant difference between the preoperative and post-discharge values. The LTA values for collagen aggregation showed a significant difference evident between the preoperative and post-discharge values; preoperative 38% (IQR: 27-60%), postoperative 42% (IQR: 30-58%), post-discharge 28% (IQR: 20-42%), respectively. We had one thromboembolic complication and one hemorrhagic complication. The results indicated that appropriate platelet aggregation monitoring during multiple antiplatelet therapy prevents thromboembolic complications such as stent thrombosis. However, we also found that many patients demonstrated increased postoperative platelet aggregation inhibitory effects due to the postoperative continuation of the same multiple antiplatelet therapy that was used preoperatively. Conclusion: This study demonstrates that postoperative, continuous, oral antiplatelet therapy induces increased platelet aggregation inhibition effects, which may lead to hemorrhagic complications. Therefore, continued platelet aggregation monitoring after surgery may be important to allow for any necessary alterations to the therapeutic dose and regimen.

[Case with large abdominal abscess associated with a ventriculoperitoneal shunt].

Abdominal abscess is a rare shunt-related complication with few reported cases. A 6-year-old female presented with a large staphylococcal abdominal abscess manifesting as abdominal distension without significant clinical signs or blood and cerebrospinal fluid findings of infection. The patient had undergone repeated surgeries for craniopharyngioma at 2 years of age and had suffered central pontine and extrapontine myelinolysis during the clinical course, had severely impaired hypothalamic function, and was in a vegetative state on presentation. In addition, she had previously suffered epidural, subdural, and cerebral parenchymal abscesses, which had resolved completely. She underwent percutaneous irrigation drainage of pus and removal of the shunt coupled with intense antibiotic administration, which cured the abscess without recurrence. Culture revealed methicillin-resistant Staphylococcus aureus. We thought that preexisting intracranial infection, which had extended down into the abdominal cavity through the peritoneal tube of the shunt, coupled with the patient's impaired immune function, had probably caused the abdominal abscess. Abdominal abscess is a potential complication of ventriculoperitoneal shunting, and timely diagnosis and treatment may achieve a good outcome.

Histological and Transmission Electron Microscopy Results after Embolization with HydroSoft/HydroFrame Coils in Experimental Swine Aneurysm.

Coiling and clipping are standard treatment strategies for cerebral aneurysms. Regardless of the strategy used, recanalization may affect the patient's prognosis. The aim of this study was to histologically and morphologically compare the tissue proliferation after coil embolization using bare platinum coils versus second-generation hydrogel coils (HydroSoft/HydroFrame; MicroVention, Inc., Aliso Viejo, CA, USA). Endothelial-like cell proliferation was seen in both groups at 2 weeks after surgery. Macroscopic findings showed a tighter layer at 4 weeks in the hydrogel coil group, and histological and immunohistochemical findings revealed endothelial cell proliferation. This layer became much thicker and tighter at 4 weeks after surgery. Aneurysms treated with second-generation hydrogel coils may be more stable and have a lower incidence of recanalization than those treated with bare platinum coils because of the tight endothelial layer proliferation.

[Huge falx meningioma resected en bloc following acute brain swelling: a case report].

Surgery of a meningioma is composed of four essential consecutive steps; devascularization, detachment, debulking, and dissection. However, this is not the case with a huge meningioma in which circumferential devascularization and detachment may be difficult to complete before debulking is attempted. We report a case of a 37-year-old female presented headache, memory disturbance, and character change and sustaining a huge falx meningioma, with hypervascular appearance. Intraoperatively her blood pressure decreased to 45/30 mmHg due to profuse bleeding caused by "premature debulking" followed by significant brain swelling, which pushed out the tumor from the underlying brain after detachment of the tumor from the falx, and, consequently, yielded en bloc removal like a birth delivery. The histopathological diagnosis was angiomatous meningioma with prominent capillary proliferation without findings of celluar atypia. We thought that relative hyperemia in the brain surrounding the tumor, which was induced by the craniotomy, and acute brain ischemia caused by the intraoperative significant hypotension, might facilitate en bloc removal. We should be aware that huge meningiomas may cause intraoperative acute brain swelling as well as significant blood loss. Also we should carefully consider the indication and select proper candidates for presurgical cerebral angiography and tumor embolization because of the inherent risk that is apt to be underestimated.

Intercavernous sinus dural arteriovenous fistula treated with transvenous coil embolization: a case report.

The blood supply to the region of the cavernous sinus is provided by interconnecting branches of the internal and external carotid arteries, and it is from these vessels that dural arteriovenous fistulas (DAVFs) arise. It is very rare that DAVFs are located at the intercavernous sinuses region; in this case, a proper localization of the fistulous site is of extreme importance in order to successfully eliminate the disease. Here, we describe a case of a 65-year-old female with intercavernous sinus DAVF. A complete obliteration of the fistulous points was performed by coil embolization through a transvenous approach.

Sporadic intra-abdominal desmoid with acute abdomen.

We report a 72-year-old man with sporadic intra-abdominal desmoid tumor manifesting as acute abdomen. CT scan revealed an air-containing tumor 7 cm in diameter; three weeks later, the tumor had shrunk to 4 cm on antibiotics. At surgery, a tumor arising from the transverse colon mesentery and infiltrating the jejunum was resected. No recurrence occurred over a 1-year follow-up.

Radiological changes in infantile dissecting anterior communicating artery aneurysm treated endovascularly. A case report and five-year follow-up.

Intracranial aneurysms are extremely rare in infants, and to our knowledge only seven infants treated for ruptured spontaneous dissecting aneurysms have been reported. Good outcomes have been achieved with endovascular treatment of infantile aneurysm. We the endovascular treatment of a one-month-old girl for ruptured dissecting aneurysm located in the anterior communicating artery, and the unique radiological changes that were observed during the perioperative and follow-up periods. These changes suggest that blood coagulation and fibrinolytic response play a part in the repair and healing processes of dissecting aneurysms. Careful neuroradiological surveys are needed for pediatric dissecting aneurysms treated endovascularly.

Orbital cavernous hemangioma presenting with atypical appearance: case report.

A 25-year-old male presented with unilateral retroorbital dysesthesia persisting for 2 weeks followed by progressive palpebral ptosis without preceding trauma, paranasal sinus surgery, or infectious signs. Neuroophthalmological inspection revealed mildly increased intraocular pressure and exophthalmos on the affected side, without conjunctival chemosis, restriction of the extraocular movements, double vision, or visual impairment. These symptoms did not vary with posture, straining, and Valsalva maneuver. Neuroimaging showed an irregularly-shaped orbital mass without enhancement mainly situated in the medial compartment of the orbit and encasing the optic nerve. Bruit was not audible and abnormal vasculatures were not identified in and around the affected orbit. Transcranial surgical exploration through the surgical window formed by the superior and medial rectus muscles revealed a purplish elastic-soft mass, heterogeneous in consistency and tightly adhering to the surrounding tissue, so cryoprobe-assisted radical tumor resection could not be completed without jeopardizing the optic nerve. The mass was subtotally resected piecemeal without postoperative visual impairment. The histological diagnosis was cavernous hemangioma. Orbital cavernous hemangiomas may present with an atypical appearance which confuses pretreatment diagnosis and makes surgical extirpation more hazardous. Conservative surgery should be indicated for poorly demarcated orbital cavernous hemangiomas considering the usual benign clinical course and postoperative sequelae.

Pleural malignant mesothelioma causing cord infiltration through the nerve root. Case report.

A 61-year-old man presented with a rare pleural malignant mesothelioma of the spine manifesting as progressive weakness of the bilateral lower extremities, numbness in the body and both legs, and dysfunction of the bladder and bowel. He had previous occupational exposure to asbestos while working at a car repair shop and had undergone right panpleuropneumonectomy under a diagnosis of sarcomatous type mesothelioma in the right pleural space. Magnetic resonance imaging of the spine with gadolinium showed an enhanced intramedullary tumor at the T4 level. Operative findings disclosed the clouded and swollen right posterior nerve root, and the pial surface was covered by clouded arachnoid-like membrane. The removed part of the T4 posterior nerve root and intramedullary tumor revealed malignant mesothelioma with invasion spreading along the posterior nerve root. He died of respiratory failure 3 months after the diagnosis. This case shows that spinal metastasis must be considered if a patient with pleural malignant mesothelioma shows neurological worsening and neuroimaging shows an abnormal lesion in the thoracic spinal cord. However, the patient's neurological condition is very difficult to improve in the presence of spinal cord infiltration.

Orbital dermoid cyst with intratumoral inflammatory hemorrhage: case report.

An 85-year-old female presented with a 3-month history of worsening hyperlacrimation and blurred vision following blunt head injury. Her past medical history was unremarkable. Her blood examination identified no abnormal findings. Neuroophthalmological inspection revealed extraocular movement disorder and mild exophthalmos on the affected side. Her visual acuity was not disturbed. Neuroimaging showed a cystic mass located extraconally in the superolateral compartment of the anterior orbit, without enhancement by contrast medium. Surgical exploration resulted in escape of chocolate-colored, liquefied hematoma during dissection. No vascular lesion was found. A grayish-white cyst wall was found adhering strongly to the lateral and superior rectus muscles. The lacrimal gland was not identified. The mass was totally resected. Histological examination indicated dermoid cyst with inflammatory interstitial hemorrhage. No component of vascular malformation or atypia was found. Hyperlacrimation and extraocular movement improved postoperatively. We thought that the previous blunt head injury might have induced intratumoral hemorrhage in the preexisting dermoid cyst and that the escaped contents caused inflammatory irritation, resulting in the hyperlacrimation. Dermoid cyst may show atypical presentation with intratumoral hemorrhage and should always be included in the differential diagnosis of orbital tumor.