A case of facial nerve palsy caused by severe head injury treated by translabyrinthine approach.

Background: Several treatments for traumatic facial paralysis have been reported, but the role of surgery is still controversial. Case Description: A 57-year-old man was admitted to our hospital with head trauma due to a fall injury. A total body computed tomography (CT) scan showed a left frontal acute epidural hematoma associated with a left optic canal and petrous bone fractures with the disappearance of the light reflex. Hematoma removal and optic nerve decompression were performed immediately. The initial treatment was successful with complete recovery of consciousness and vision. The facial nerve paralysis (House and Brackmann scale grade 6) did not improve after medical therapy, and thus, surgical reconstruction was performed 3 months after the injury. The left hearing was lost entirely, and the facial nerve was surgically exposed from the internal auditory canal to the stylomastoid foramen through the translabyrinthine approach. The facial nerve's fracture line and damaged portion were recognized intraoperatively near the geniculate ganglion. The facial nerve was reconstructed using a greater auricular nerve graft. Functional recovery was observed at the 6-months follow-up (House and Brackmann grade 4), with significant recovery in the orbicularis oris muscle. Conclusion: Interventions tend to be delayed, but it is possible to select a treatment method of the translabyrinthine approach.

Cortical Blood Flow Insufficiency Scores with Computed Tomography Perfusion can Predict Outcomes in Aneurysmal Subarachnoid Hemorrhage Patients: A Cohort Study.

BACKGROUND: The World Federation of Neurosurgical Societies (WFNS) scale is widely accepted for predicting outcomes for subarachnoid hemorrhage (SAH) patients. However, it is difficult to definitely predict outcomes for the most poor grade, WFNS grade 5. The present study aimed to investigate the prognostic ability of a novel classification using computed tomography perfusion (CTP) findings, called the cortical blood flow insufficiency (CBFI) scores. METHODS: CTP was performed on admission for aneurysmal SAH followed by radical treatments within 72 hours of onset. Twenty-four cerebral cortex regions of interest (ROIs) were defined. CBFI was defined as Tmax > 4 s in each ROI, and CBFI scores were calculated based on the total number of ROIs with CBFI. Using the optimal cutoff value based on receiver operating characteristics (ROC) analysis to predict patient functional outcomes, CBFI scores were divided into "high" or "low" CBFI scores. Patient functional outcomes at 90 days were categorized based on modified Rankin Scale scores (0-3, favorable group; 4-6 unfavorable group) (0-4, non-catastrophic group; 5-6, catastrophic group). RESULTS: Fifty-seven patients were included in this study, of whom 21 (36.8%) and 13 (22.8%) were in the unfavorable and the catastrophic groups, respectively. A factor predicting unfavorable and catastrophic outcomes was CBFI score cutoff value of 7 points (area under the curve, 0.73 and 0.81, respectively). In multivariable logistic regression analysis for unfavorable outcome, high CBFI scores (odds ratio (OR), 8.6; 95% confidence interval (CI), 1.1-65.4; P = 0.04) and WFNS grade 5 (OR, 30.0; 95% CI, 4.5-201.0; P < 0.001) remained as independent predictors, while for catastrophic outcome, high CBFI scores (OR, 25.3; 95% CI, 3.3-194.0; P = 0.002) and age (OR, 1.1; 95% CI, 1.0-1.2; P = 0.02) remained as independent predictors. Conversely, WFNS grade 5 was not an independent predictor of catastrophic outcomes (OR, 3.8; 95% CI, 0.6-24.0; P = 0.15). In high CBFI scores, the OR of the delayed cerebral ischemia (DCI) occurrence was 9.6 (95% CI, 1.5-61.4; P = 0.02) after adjusting for age. CONCLUSION: High CBFI scores could predict unfavorable and catastrophic outcomes for aneurysmal SAH patients and DCI occurrence.

Experimental Analysis of Intra-luminal Pressure by Contrast Injection during Mechanical Thrombectomy: Simulation of Rupture Risk of Hidden Cerebral Aneurysm in Tandem Occlusion with Blind Alley.

Mechanical thrombectomy using a retrograde approach is performed for tandem occlusion of the internal carotid artery (ICA). In our patient, a guiding catheter was easily passed by the stenosed lesion despite severe stenosis at the ICA origin. Therefore, we aimed to recanalize the occlusion of the terminal ICA without angioplasty for the stenosed lesion. When contrast was injected, a massive extravasation of contrast from the C2 portion of the ICA was observed. It was speculated that the bleeding was caused by rupture of an aneurysm at that site due to increased intra-arterial pressure caused by the contrast injection to a blind alley, which was created by a wedged guiding catheter at severe stenosis at the ICA origin and the occlusion of the terminal ICA. Our simulation experiment using a silicon vascular model in this situation demonstrated that the elevation of intra-arterial pressure in such blind alley reached over 50, 100, and 200 mmHg by injection of contrast from a microcatheter, a 4-Fr inner catheter, and a 9-Fr balloon-guiding catheter, respectively. When a retrograde approach is planned for tandem occlusion of the ICA, even when the proximal lesion is easily passed, prior angioplasty for the proximal lesion should be considered to avoid wedging by catheter.

Radical treatment for bilateral vertebral artery dissecting aneurysms by reconstruction of the vertebral artery.

OBJECTIVE Bilateral vertebral artery dissecting aneurysms (VADAs) have a poor prognosis because progressive enlargement of the aneurysms compresses the brainstem or causes subarachnoid hemorrhage. The trapping of 1 vertebral artery (VA) places increased hemodynamic stress on the contralateral VA and may lead to enlargement and rupture. Therefore, management strategies are controversial. This study describes a radical treatment for bilateral VADAs using bypass surgery. METHODS Seven patients with bilateral VADAs were included. Three patients were treated by trapping of 1 VA via coiling or clipping at another hospital; the previously treated VA in 1 patient and the contralateral untreated VA in 2 patients subsequently enlarged. The other 4 patients presented without previous intervention and progressive enlargement of the aneurysms. RESULTS The post-coil embolization patients underwent V3-posterior cerebral artery (PCA) bypass and trapping. The other 4 patients underwent VA reconstruction via V3-V4 or V4-V4 bypass, with contralateral trapping on a separate day in 3 patients and observation in 1 patient. Perioperative complications included 1 case of cerebrospinal fluid leakage for which the patient required an additional operation, 1 case of dysphagia and facial palsy due to sigmoid sinus thrombosis, and 1 case of dysphagia. The long-term outcomes of these patients were favorable. CONCLUSIONS Patients with bilateral VADAs require treatment on both sides. If VA trapping is performed first, the treatment options for the other side are limited to V3-PCA bypass and trapping. This procedure is effective; however, it is also invasive and technically difficult. In cases of bilateral VADAs in which it is feasible to reconstruct 1 side, the best approach is to begin by reconstructing the VA that appears technically easiest, followed by trapping of the contralateral VADA. This strategy allows enough time to suture vessels because contralateral reverse flow is maintained.

Risk factors for neurological worsening and symptomatic watershed infarction in internal carotid artery aneurysm treated by extracranial-intracranial bypass using radial artery graft.

OBJECT The revascularization technique, including bypass created using the external carotid artery (ECA), radial artery (RA), and M2 portion of middle cerebral artery (MCA), has remained indispensable for treatment of complex aneurysms. To date, it remains unknown whether diameters of the RA, superficial temporal artery (STA), and C2 portion of the internal carotid artery (ICA) and intraoperative MCA blood pressure have influences on the outcome and the symptomatic watershed infarction (WI). The aim of the present study was to evaluate the factors for the symptomatic WI and neurological worsening in patients treated by ECA-RA-M2 bypass for complex ICA aneurysm with therapeutic ICA occlusion. METHODS The authors measured the sizes of vessels (RA, C2, M2, and STA) and intraoperative MCA blood pressure (initial, after ICA occlusion, and after releasing the RA graft bypass) in 37 patients. Symptomatic WI was defined as presence of the following: postoperative new neurological deficits, WI on postoperative diffusion-weighted imaging, and ipsilateral cerebral blood flow reduction on SPECT. Neurological worsening was defined as the increase in 1 or more modified Rankin Scale scores. First, the authors performed receiver operating characteristic curve analysis for continuous variables and the binary end point of the symptomatic WI. The clinical, radiological, and physiological characteristics of patients with and without the symptomatic WI were compared using the log-rank test. Then, the authors compared the variables between patients with and without neurological worsening at discharge and at the 12-month follow-up examination or last hospital visit. RESULTS Symptomatic WI was observed in 2 (5.4%) patients. The mean MCA pressure after releasing the RA graft (< 55 mm Hg; p = 0.017), mean (MCA pressure after releasing the RA graft)/(initial MCA pressure) (< 0.70 mm Hg; p = 0.032), and mean cross-sectional area ratio ([RA/C2 diameter](2) < 0.40 mm [p < 0.0001] and [STA/C2 diameter](2) < 0.044 mm [p < 0.0001]) were related to the symptomatic WI. All preoperatively independent patients remained independent (modified Rankin Scale score < 3). After adjusting for age and sex, left operative side (p = 0.0090 and 0.038) and perforating artery ischemia (p = 0.0050 and 0.022) were related to neurological worsening at discharge (11 [29%] patients) and at the 12-month follow-up or last hospital visit (8 [22%] patients). CONCLUSIONS Results of the present study showed that the vessel diameter and intraoperative MCA pressure had impacts on the symptomatic WI and that operative side and perforating artery ischemia were related to neurological worsening in patients with complex ICA aneurysms treated by ECA-RA-M2 bypass.

Surgical microanatomy of the anterior clinoid process for paraclinoid aneurysm surgery and efficient modification of extradural anterior clinoidectomy.

BACKGROUND: Anatomic variations of the anterior clinoid process (ACP) should be recognized before clinoidectomy to ensure a safe approach. This study describes the incidence of caroticoclinoid foramen (CCF), interclinoid osseous bridge, and pneumatization of the ACP during extradural anterior clinoidectomy. The problems and technical issues encountered in such cases are described. METHODS: Using multidetector-row computed tomography, 144 sides in 72 cases of paraclinoid aneurysm treated by extradural anterior clinoidectomy were analyzed preoperatively. RESULTS: CCF, interclinoid osseous bridge, and pneumatization of the ACP were observed in 16.6%, 2.77%, and 27.7% of cases. Pneumatized patterns were divided into 3 groups according to route: pneumatization via the optic strut (in 74.1%), pneumatization via the anterior root (in 14.8%), and pneumatization via optic strut and anterior root (in 11.1%). CCF and interclinoid osseous bridge represent obstacles to complete extradural removal of the ACP. The ACP should not be moved even after drilling the lateral wall of the ACP, orbital roof, and optic strut, so an intradural approach is sometimes needed. A CCF warrants careful removal to open the distal dural ring. Awareness of the routes of pneumatization for the ACP should reduce the risk of tears in the paranasal mucosa. If tears arise in the mucosa, suturing and closure are needed to prevent liquorrhea. CONCLUSIONS: Preoperative computed tomography is useful to detect variations in the anatomy around the ACP. When performing extradural anterior clinoidectomy in such anomalous cases, appropriate modifications are needed to ensure a safe approach.

Contralateral approach to unruptured superior hypophyseal artery aneurysms.

OBJECTIVE: To evaluate the feasibility and limitations of the contralateral approach to unruptured superior hypophyseal artery (SHA) aneurysms. METHODS: Data regarding eight cases of superior hypophyseal artery aneurysms operated on by a contralateral pterional approach at our center from January 2008 to September 2010 were collected and evaluated retrospectively. Of these eight cases, six were male and two were female. The mean age was 57.1 years (range 28 years to 77 years). All the aneurysms were unruptured; five were on right side and three were on left side. The surgical technique and outcome of patients were reviewed. RESULTS: All aneurysms were successfully clipped without complication and patency of all superior hypophyseal arteries was preserved. Postoperative three-dimensional computed tomography angiography revealed residual aneurysm in only one case. None of the patients had deterioration of visual acuity or field after surgery. The contralateral pterional approach was found to be appropriate for fully exposing the aneurysmal dome and neck without retraction of the optic nerve or the carotid artery in five cases. Slight retraction of the optic nerve was required in two cases, and significant manipulation of the optic nerve was required in one case. CONCLUSIONS: The contralateral pterional approach for clipping of unruptured superior hypophyseal artery aneurysms is technically feasible and safe in a select group of patients where optimal results can be achieved without significant retraction of near by neurovascular structures.

Intraoperative near-infrared indocyanine green-videoangiography (ICG-VA) and graphic analysis of fluorescence intensity in cerebral aneurysm surgery.

We present our preliminary experience with intraoperative near-infrared indocyanine green-videoangiography (ICG-VA) and analysis of blood flow dynamics using fluorescence intensity assessment in cerebral aneurysm clipping surgery. Thirty-nine patients with 43 intracranial aneurysms underwent microsurgical clipping. Intraoperative ICG-VA was performed before and after clip application. An infrared fluorescence module integrated into a surgical microscope was used to visualize fluorescence in the surgical field and we recorded the emitted fluorescent light. An integrated analytical visualization tool simultaneously analyzed the video sequence and converted it into an intensity diagram, which allowed an objective evaluation of the results rather than the subjective assessment of fluorescence using ICG-VA. Overall, ICG-VA was performed 137 times. Incomplete clipping was detected in four patients, which allowed suitable adjustment to completely obliterate the aneurysm. In 12 patients, perforators arising close to, or from, the aneurysmal neck were identified in the surgical field. In three patients, the ICG-VA intensity diagram provided valuable information leading to modification of the primary surgical maneuver. ICG-VA provides high resolution images allowing real-time assessment of the blood flow in the parent artery and arterial branches, including the perforators. The intensity diagram is useful for providing a more objective record of the hemodynamics than the traditional ICG-VA, which relies more on subjective assessment and may allow interobserver variability. We conclude that ICG-VA, combined with the intensity diagram, can reduce the morbidity and complications associated with aneurysm clipping and improve patient outcomes.

Neuroprotective effect of exogenous microglia in global brain ischemia.

Exogenous microglia pass through the blood-brain barrier and migrate to ischemic hippocampal lesions when injected into the circulation. We investigated the effect of exogenous microglia on ischemic CA1 pyramidal neurons. Microglia were isolated from neonatal mixed brain cultures, labeled with the fluorescent dye PKH26, and injected into the subclavian artery of Mongolian gerbils subjected to ischemia reperfusion neuronal injury. PKH26-labeled microglia migrated to the ischemic hippocampal lesion, resulting in increased numbers of surviving neurons compared with control animals, even when injected 24 h after ischemia. Interferon-gamma stimulation of isolated microglia enhanced the neuroprotective effect. Administration of exogenous microglia resulted in normal performance in a passive avoidance-learning task. Additionally, administration of exogenous microglia increased the expression of brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor in the ischemic hippocampus, and thus might have induced neurotrophin-dependent protective activity in damaged neurons. Peripherally injected microglia exhibited a specific affinity for ischemic brain lesions, and protected against ischemic neuronal injury in vivo. It is possible that administration of exogenous microglia can be developed as a potential candidate therapy for central nervous system repair after transitory global ischemia.