Soichi Oya

Analysis of risk factors for chronic subdural haematoma recurrence after burr hole surgery: optimal management of patients on antiplatelet therapy.

Abstract Objective. Not much is known about surgical management of patients with chronic subdural haematoma (CSDH) treated with antiplatelet or anticoagulant therapy. The aims of this study were to review the surgical outcomes of patients with CSDH and assess the risks of antiplatelet in their surgical management. Methods. We retrospectively analysed 448 consecutive patients with CSDH treated by one burr hole surgery at our institution. Among them, 58 patients had been on antiplatelet therapy. We discontinued the antiplatelet agents before surgery for all 58 patients. For 51 of these 58 patients (87.9%), early surgery was performed within 0–2 days from admission. We analysed the association between recurrence and patient characteristics, including history of antiplatelet or anticoagulant therapy; age (< 70 years or ≥ 70 years); side; history of angiotensin receptor II blocker, angiotensin converting enzyme blocker, or statin therapy; and previous medical history of head trauma, infarction, hypertension, diabetes mellitus, haemodialysis, seizure, cancer, or liver cirrhosis. Results. Recurrence occurred in 40 patients (8.9%), which was one of the lowest rates in the literature. Univariate analysis showed that only the presence of bilateral haematomas was associated with increased recurrence rate while antiplatelet or anticoagulant therapy did not significantly increase recurrence risk. Also, the recurrence rate from early surgery (0–2 days from drug cessation) for patients on antiplatelet therapy was not significantly higher than that from elective surgery (5 days or more after drug cessation). However, multivariate analysis revealed that previous history of cerebral infarction was an independent risk factor for CSDH recurrence. Conclusions. Our overall data support the safety of early surgery for patients on the preoperative antiplatelet therapy without drug cessation or platelet infusion. Patients with a previous history of infarction may need to be closely followed regardless of antiplatelet or anticoagulant therapy.

Beneficial Effect of Selective Intra-arterial Infusion of Fasudil Hydrochloride as a Treatment of Symptomatic Vasospasm Following SAH

INTRODUCTION We envisage the efficacy and safety of intra-arterial infusion of fasudil hydrochloride (IAF) for symptomatic vasospasm (SVS) after subarachnoid hemorrhage (SAH). We compared results obtained from the groups that received selective IAF (a microcatheter inserted in intracranial arteries) and nonselective IAF (a microcatheter inserted in the cervical arteries). Glasgow Outcome Scale (GOS) value and computed tomographic (CT) score were used to evaluate clinical outcome and the extent of infarction due to delayed vasospasm. MATERIAL AND METHODS Over 2 years, 113 patients with SAH underwent clipping or coiling. Among them, 31 patients (27.4%) developed SVS. We performed nonselective IAF in 10 patients and selective IAF in 10 other patients. Eleven patients with SVS were treated without IAF. The data were statistically analyzed. RESULT By univariate linear regression analysis, IAF negatively correlated with CT score (p = 0.016), but IAF was significantly correlated with GOS (p = 0.035). By multiple regression analysis, Hunt and Kosnik grade and CT score significantly correlated with GOS. DISCUSSION CT score significantly correlated with functional outcome. Although IAF, both selective and nonselective, was significantly effective for the treatment of delayed vasospasm, the former seemed to be more beneficial.

Solitary Osteochondroma of the Skull Base: A Case Report and Literature Review

We report a case of an osteochondroma in the posterior clinoid process that occurred in a 43-year-old man with trochlear nerve palsy. Although the potential preoperative diagnoses based on computed tomography and magnetic resonance imaging included other intracranial tumors such as calcified meningioma, thallium-201 single-photon emission computed tomography effectively differentiated osteochondroma from those possibilities. Via an orbitozygomatic approach, a subtotal resection was achieved with a good relief of symptoms. Twenty-two cases of solitary osteochondromas in the skull base have been reported that have demonstrated little risk of recurrence or malignant transformation. However, surgery for skull base osteochondromas does carry a significant risk with a reported mortality > 10%. Although some previous reports advocate complete resection as the only curative method for skull base osteochondromas, the risks of total resection should be weighed against the chance for recurrence; our review of the literature demonstrated a relatively high mortality and an extremely low incidence of recurrence.

Syringomyelia associated with arachnoid septum at the craniovertebral junction, contradicting the currently prevailing theory of syringomyelia formation

Despite a number of various hypotheses in the literature, the pathophysiology of syringomyelia is still not well understood. In this article, we report two cases of cervical syringomyelia not associated with Chiari I malformation. Both cases had a septum-like structure in the subarachnoid space on the dorsal side of the cord at the craniovertebral junction. Cardiac-gated phase-contrast cine-mode magnetic resonance imaging (MRI) demonstrated decreased cerebrospinal fluid (CSF) flow on the dorsal side of the spinal cord. Surgical excision of this septum, restoring the CSF flow, resulted in a prompt reduction of the syrinx size in both cases. Findings in these cases contradict the currently prevailing hypothesis of syrinx formation that postulate that the piston-like movement of the cerebellar tonsils enhance the pulsatile CSF flow in the spinal subarachnoid space, driving the CSF into the syrinx through the perivascular space of Virchow and Robin. The authors propose that a mechanism based on the decreased pulsatile CSF flow in the spinal subarachnoid space will be more suitable as a hypothesis in studying the pathophyisiology of syringomyelia. These cases also provide an important lesson in managing the patients with syringomyelia not associated with Chiari I malformation.

Ruptured Basilar Tip Aneurysm in a Patient with Bilateral Internal Carotid Artery Occlusion Successfully Treated with Bilateral Superficial Temporal Artery–Middle Cerebral Artery Anastomoses: Case Report

BACKGROUND Some ruptured intracranial aneurysms concomitant with major artery occlusion may not be amenable for standard clipping or coiling due to the specific hemodynamic conditions. The long-term effect of flow reduction therapy for such aneurysms is largely unknown. CASE PRESENTATION A 45-year-old woman presented with subarachnoid hemorrhage due to a ruptured basilar tip aneurysm. Angiography revealed that the bilateral internal carotid arteries were hypoplastic and that the anterior circulation was fed by the collateral flow through the bilateral posterior communicating arteries and the posterior choroidal arteries. Endovascular treatment failed because it was extremely difficult to secure the catheter at the neck of the aneurysm and insert the coil safely because it was a small aneurysm with a wide neck. In addition, direct clipping was risky due to the location and projection of the aneurysm. We therefore adopted the 2-stage bilateral superficial temporal artery-middle cerebral artery bypass to alleviate the vascular demand on the anterior circulation, with the aim of reducing the hemodynamic stress to the basilar bifurcation. The patient had no rebleeding for 4 years after surgery, with gradual shrinkage of the aneurysm. CONCLUSION All the possible treatment options should be carefully assessed because the long-term effect of the flow alternation method to prevent rebleeding has not been proved. However, our case suggests that the strategy of reducing the hemodynamic stress at the parent artery may be effective even in selected cases of ruptured aneurysms for which standard clipping or coiling is not feasible.

Limitations of Routine Verification of Nasogastric Tube Insertion Using X-ray and Auscultation Two Case Reports of Life-Threatening Complications

Several bedside approaches used in combination with thoracoabdominal X-ray are widely used to avoid severe complications that have been reported during nasogastric tube management. Although confirmation by X-ray is considered the gold standard, it is not yet perfect. We present 2 cases of rare complications in which the routine verification methods could not detect all the complications related to the nasogastric tube placement. Case 1 was a 17-year-old male who presented with a brain tumor and repeatedly required nasogastric tube placement. Despite normal auscultatory and X-ray findings, the patients condition deteriorated rapidly after resuming the enteral nutrition (EN). Computed tomography images showed the presence of hepatic portal venous gas (HPVG). Urgent upper gastrointestinal endoscopy showed esophagogastric submucosal tunneling of the tube that required an emergency open total gastrectomy. Case 2 was a 76-year-old man with long-term EN after stroke. While the last auscultatory verification was normal, he suddenly developed extensive HPVG due to gastric mucosal injury following EN, which resulted in progressive intestinal necrosis, general peritonitis, and death. These 2 cases indicated that routine verification methods consisting of auscultation and X-ray may not be completely reliable, and the awareness of the limitations of these methods should be reaffirmed because expeditious examinations and necessary interventions are critical in preventing life-threatening complications.

Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids with a Significant Elevation of β-2 Microglobulin Levels

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a relapsing-remitting disorder for which steroid administration is a key to control the progression. CLIPPERS can exhibit radiological features similar to malignant lymphoma, whose diagnosis is confounded by prior steroid administration. We report a case of CLIPPERS accompanied by abnormal elevation of β-2 microglobulin in the cerebrospinal fluid (CSF). A 62-year-old man started to experience numbness in all fingers of his left hand one year ago, which gradually extended to his body trunk and legs on both sides. Magnetic resonance imaging demonstrated numerous small enhancing spots scattered in his brain and spinal cord. CSF levels of β-2 microglobulin were elevated; although this often indicates central nervous system involvement in leukemia and lymphoma, the lesions were diagnosed as CLIPPERS based on the pathological findings from a biopsy specimen. We emphasize the importance of biopsy to differentiate between CLIPPERS and malignant lymphoma because the temporary radiological response to steroid might be the same in both diseases but the treatment strategies regarding the use of steroid are quite different.

Pearls & Oy-sters: Anorexia and emaciation in patients with cerebellar hemangioblastoma

Anorexia and emaciation result from various conditions, including digestive diseases, metabolic disorders, chronic inflammation, chronic infections, malignancies, and psychiatric problems. Intracranial tumors can also cause a reduction in food intake, thus mimicking anorexia nervosa, through various mechanisms. Fourth ventricular tumors, particularly hemangioblastomas, can cause prolonged appetite loss and extreme body weight loss, without any apparent focal neurologic deficits.

Ultra-Early Optic Nerve Decompression for the Resection of Anterior Clinoidal Meningioma

Improvement in vision is one of the main goals of surgery for anterior clinoidal meningiomas with visual deficits. Early optic nerve decompression surgery has been advocated in previous studies to achieve the best visual outcome. Through this video, the authors describe their surgical techniques to decompress the optic nerve at the very early stage of surgery. A 35-year-old patient presented with subjective blurry vision in the right eye over the last 8 months. Magnetic resonance images showed a 3.2-cm meningioma arising at the right anterior clinoid. Preoperative ophthalmological test was within the normal range, but the patient wished to have surgical resection after a detailed discussion of benefits and risks related to surgical resection. The surgical strategy consisted of the right lateral subfrontal approach that includes a standard right frontotemporal craniotomy, extradural anterior clinoidectomy, and early optic nerve decompression prior to tumor resection. The tumor was divided into compartments defined by the arteries and resected. Simpson grade II resection was achieved without complications. The patients symptoms disappeared. In anterior clinoidal meningiomas that cause visual deficits, the optic nerve is assumed very vulnerable to any further injuries related to the operative maneuver. Ultra-early optic nerve decompression can be performed in anterior clinoidal meningiomas regardless of their size by extradural unroofing of the optic canal and sectioning of the optic canal sheath, which we believe contributes to better visual improvement. The link to the video can be found at: https://youtu.be/RIFi4ecWAhQ .