Thin-slice reverse encoding distortion correction DWI facilitates visualization of non-functioning pituitary neuroendocrine tumor (PitNET)/pituitary adenoma and surrounding normal structures.

BACKGROUND: To evaluate the clinical usefulness of thin-slice echo-planar imaging (EPI)-based diffusion-weighted imaging (DWI) with an on-console distortion correction technique, termed reverse encoding distortion correction DWI (RDC-DWI), in patients with non-functioning pituitary neuroendocrine tumor (PitNET)/pituitary adenoma. METHODS: Patients with non-functioning PitNET/pituitary adenoma who underwent 3-T RDC-DWI between December 2021 and September 2022 were retrospectively enrolled. Image quality was compared among RDC-DWI, DWI with correction for distortion induced by B0 inhomogeneity alone (B0-corrected-DWI), and original EPI-based DWI with anterior-posterior phase-encoding direction (AP-DWI). Susceptibility artifact, anatomical visualization of cranial nerves, overall tumor visualization, and visualization of cavernous sinus invasion were assessed qualitatively. Quantitative assessment of geometric distortion was performed by evaluation of anterior and posterior displacement between each DWI and the corresponding three-dimensional T2-weighted imaging. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient values were measured. RESULTS: Sixty-four patients (age 70.8 ± 9.9 years [mean ± standard deviation]; 33 females) with non-functioning PitNET/pituitary adenoma were evaluated. In terms of susceptibility artifacts in the frontal and temporal lobes, visualization of left trigeminal nerve, overall tumor visualization, and anterior displacement, RDC-DWI performed the best and B0-corrected-DWI performed better than AP-DWI. The right oculomotor and right trigeminal nerves were better visualized by RDC-DWI than by B0-corrected-DWI and AP-DWI. Visualization of cavernous sinus invasion and posterior displacement were better by RDC-DWI and B0-corrected-DWI than by AP-DWI. SNR and CNR were the highest for RDC-DWI. CONCLUSIONS: RDC-DWI achieved excellent image quality regarding susceptibility artifact, geometric distortion, and tumor visualization in patients with non-functioning PitNET/pituitary adenoma. RELEVANCE STATEMENT: RDC-DWI facilitates excellent visualization of the pituitary region and surrounding normal structures, and its on-console distortion correction technique is convenient. RDC-DWI can clearly depict cavernous sinus invasion of PitNET/pituitary adenoma even without contrast medium. KEY POINTS: • RDC-DWI is an EPI-based DWI technique with a novel on-console distortion correction technique. • RDC-DWI corrects distortion due to B0 field inhomogeneity and eddy current. • We evaluated the usefulness of thin-slice RDC-DWI in non-functioning PitNET/pituitary adenoma. • RDC-DWI exhibited excellent visualization in the pituitary region and surrounding structures. • In addition, the on-console distortion correction of RDC-DWI is clinically convenient.

Impact of collagen matrix on reconstructive material selection and postoperative complications in endoscopic endonasal skull base surgery.

OBJECTIVE: The aim of this study was to investigate the impact of collagen matrix on reconstructive material selection and postoperative complications in endoscopic endonasal skull base surgery. METHODS: The authors retrospectively reviewed the data of consecutive patients who underwent purely endoscopic endonasal skull base surgery from January 2015 to March 2023. Intraoperative CSF leakage was classified according to the Esposito grade, and skull base repair was tailored to the leakage grade. The patients were divided into two groups: before (group A) and after (group B) collagen matrix implementation. The rates of autologous graft harvesting (fat, fascia, and nasoseptal flap), postoperative CSF leakage, and donor-site complications were compared between the two groups. RESULTS: In total, 270 patients were included. Group A included 159 patients and group B included 111 patients. There were no differences in patient characteristics, including age, pathology, and Esposito grade, between the two groups. The overall fat usage rate was significantly higher in group A (63.5%) than in group B (39.6%) (p = 0.0001), and the fascia usage rate was also significantly higher in group A (25.8%) than in group B (4.5%) (p < 0.0001). The nasoseptal flap usage rate did not differ between group A (32.7%) and group B (30.6%) (p = 0.79). Postoperative CSF leakage was similar between the two groups (0.63% in group A vs 1.8% in group B, p = 0.57), and the overall rate of CSF leakage was 1.1%. Donor-site complications occurred in 3 patients in group A, including 1 abdominal hematoma, 1 delayed abdominal infection, and 1 fluid collection after fascia lata harvesting. CONCLUSIONS: Collagen matrix implementation significantly decreased autologous graft harvesting without increasing postoperative CSF leakage, contributing to less invasive surgery.

High intratumoral susceptibility signal grade on susceptibility-weighted imaging: a risk factor for hemorrhage after stereotactic biopsy.

OBJECTIVE: This study aimed to examine the association of preoperative intratumoral susceptibility signal (ITSS) grade with hemorrhage after stereotactic biopsy (STB). METHODS: The authors retrospectively reviewed 66 patients who underwent STB in their institution. Preoperative factors including age, sex, platelet count, prothrombin time-international normalized ratio, activated thromboplastin time, antiplatelet agent use, history of diabetes mellitus and hypertension, target location, anesthesia type, and ITSS data were recorded. ITSS was defined as a dot-like or fine linear low signal within a tumor on susceptibility-weighted imaging (SWI) and was graded using a 3-point scale: grade 1, no ITSS within the lesion; grade 2, 1-10 ITSSs; and grade 3, ≥ 11 ITSSs. Postoperative final tumor pathology was also reviewed. The association between preoperative variables and the size of postoperative hemorrhage was examined. RESULTS: Thirty-four patients were men and 32 were women. The mean age was 66.6 years. The most common tumor location was the frontal lobe (27.3%, n = 18). The diagnostic yield of STB was 93.9%. The most common pathology was lymphoma (36.4%, n = 24). The ITSS was grade 1 in 37 patients (56.1%), grade 2 in 14 patients (21.2%), and grade 3 in 15 patients (22.7%). Interobserver agreement for ITSS was almost perfect (weighted kappa = 0.87; 95% CI 0.77-0.98). Age was significantly associated with ITSS (p = 0.0075). Postoperative hemorrhage occurred in 17 patients (25.8%). Maximum hemorrhage diameter (mean ± SD) was 1.78 ± 1.35 mm in grade 1 lesions, 2.98 ± 2.2 mm in grade 2 lesions, and 9.51 ± 2.11 mm in grade 3 lesions (p = 0.01). Hemorrhage > 10 mm in diameter occurred in 10 patients (15.2%), being symptomatic in 3 of them. Four of 6 patients with grade 3 ITSS glioblastomas (66.7%) had postoperative hemorrhages > 10 mm in diameter. After adjusting for age, ITSS grade was the only factor significantly associated with hemorrhage > 10 mm (p = 0.029). Compared with patients with grade 1 ITSS, the odds of postoperative hemorrhage > 10 mm in diameter were 2.57 times higher in patients with grade 2 ITSS (95% CI 0.31-21.1) and 9.73 times higher in patients with grade 3 ITSS (95% CI 1.57-60.5). CONCLUSIONS: ITSS grade on SWI is associated with size of postoperative hemorrhage after STB.

Ruptured fungal mycotic internal carotid artery aneurysm successfully treated with stent-assisted coil embolization: A case report.

Background: Ruptured intracranial fungal mycotic aneurysms have a high mortality rate. It has been reported that the number of opportunistic infections has increased. Here, we report the first case of a patient in which a ruptured fungal carotid artery aneurysm was successfully treated by stent-assisted coil embolization. Case Description: A 76-year-old male receiving dual antiplatelet therapy due to a recent percutaneous transluminal angioplasty presented with blurred vision of the right eye and diplopia. Magnetic resonance imaging revealed a fungal mass in the sphenoid sinus, and the patient was pathologically diagnosed with invasive aspergillosis. After receiving oral voriconazole for 4 weeks, he was admitted to the hospital with hemorrhagic shock from epistaxis. The right internal carotid artery angiography revealed a de novo irregularly shaped aneurysm at the cavernous portion, projecting into the sphenoid sinus, which was considered to be the source of bleeding. Due to the lack of ischemic tolerance and urgent demand for hemostasis, we performed a stent-assisted coil embolization of the aneurysm without interrupting the blood flow. Postoperatively, the patient had no neurological deficit, and treatment with voriconazole was continued for 12 months without rebleeding. Conclusion: Stent-assisted coil embolization without parent artery occlusion might be a promising option for the urgent treatment of ruptured fungal mycotic aneurysms. Long-term administration of voriconazole might be continued for 12 months for such patients.

Diagnosis of spinal dural defect using three-dimensional fast steady-state MR in patient with superficial siderosis: A case report.

Background: Spinal dural defects can result in superficial siderosis (SS) of the central nervous system. Closure of the defect can stop or slow the progression of the disease. Here, we evaluated, whether preoperative three-dimensional fast steady-state acquisition MR could adequately detect these defects and, thus, facilitate their closure and resolution. Case Description: A 65-year-old right-handed male presented with a 33-year history of the left C8 root avulsion and a 3-year history of slowly progressive gait difficulties and hearing loss. The T2*-weighted imaging revealed symmetrical hemosiderin deposition throughout his central nervous system. A left C6-C7 dural defect involving only inner layer was identified using a three-dimensional MR (3D-FIESTA). It was treated through a left C6-7 hemilaminectomy and successfully sealed with adipose tissue and fibrin glue. Subsequently, the progression of cerebellar ataxia was halted, nevertheless the sensorineural hearing loss worsened even over the next 2 years. Conclusion: 3D-FIESTA reconstruction was approved to be useful tool for identifying the tiny hole of the inner dural layer responsible for SS.

Case of a Stuck Coil in the Final Stage of Stent-Assisted Coil Embolization.

Objective: We report a case in which two coils became stuck in a microcatheter at the end of coil embolization for a cerebral aneurysm. Case Presentation: Two coils became stuck in the microcatheter at the final stage of stent-assisted coil embolization for an unruptured anterior communicating artery aneurysm. The rear end of a detached coil was near the tip of the microcatheter. The coil inserted next was pushed out of the microcatheter and pulled back into the microcatheter. Then, the rear end of the detached coil and the retracted coil meshed into the microcatheter, and became immobile. The microcatheter and these two coils were removed simultaneously, and coil embolization was finished. Conclusion: At the end of coil embolization, the filling rate is relatively high. Insertion of another coil and traction may cause the coils to become stuck in the microcatheter.

Effects of acute angle, proximal bending, and distal bending in the deployment vessels on incomplete low-profile visualized intraluminal support (LVIS) expansion: an in vitro study.

BACKGROUND: A low-profile visualized intraluminal support (LVIS) device may incompletely expand during stent deployment in tortuous vessels. However, the cause of incomplete expansion remains uninvestigated. We aimed to examine in vitro the factors causing incomplete expansion in LVIS deployment by using various vessel models. METHODS: A linear model group was created by connecting linear silicone tubes (inner diameter 4 mm) at both sides of the LVIS deployment vessel (inner diameter 4 mm) with different curvature angles of 10-140° at 10° intervals. For comparison, proximal and distal bending model groups were created, both with 90° bending on the proximal/distal larger curvature side of the deployment vessel. A single operator macroscopically deployed an LVIS (4.5×32 mm) four times in each model and 56 times in each group. RESULTS: In each model group the LVIS deployment vessel with a narrow curvature angle incompletely expanded. Incomplete expansion occurred significantly more frequently in the distal bending model group (34%, 19/56) compared with that in the linear model group (14.3%, 8/56; p<0.001), as well as in the proximal bending model group (59%, 33/56) compared with that in the distal bending model group (p<0.05). Compared with the linear model group, the proximal bending model group had a significantly reduced angle between the LVIS and the direction of the LVIS pushing force, but no significant change was found in the distal bending model group compared with that in the linear model group. CONCLUSIONS: Factors such as acute angle, distal bending, and proximal bending of the deployment vessel can cause incomplete LVIS expansion.

Dissection of the Vertebral Artery Fenestration Limb Presenting with Occlusion After Rupture.

BACKGROUND: Dissection of a vertebral artery (VA) fenestration is extremely rare. We herein present the first case of a patient who presented with the dissection of a VA fenestration limb accompanied by occlusion after rupture, who was treated with internal trapping of the dissected limb and the parent artery proximal to the fenestration. CASE DESCRIPTION: A 55-year-old man presented with sudden headache and altered consciousness. Computed tomography at admission showed subarachnoid hemorrhage. Angiography showed occlusion of the inner limb of the vertebrobasilar junction fenestration, and the occluded ends had a tapered shape, suggesting the occlusion of the dissection of the inner limb after rupture. Angiography immediately before embolization revealed inner limb recanalization with an irregular string sign; thus only the inner limb was embolized. Angiography after embolization showed near-complete suppression of the blood flow in the inner limb; however, a slight antegrade flow through the coil mass was observed in the late phase. The procedure was finished with the expectation of complete occlusion over time with natural heparin reversal. Angiography 8 days after embolization revealed a significant increase in antegrade blood flow through the coil mass within the inner limb. Therefore additional embolization of the parent artery proximal to the fenestration was performed, which achieved complete occlusion. CONCLUSIONS: The embolization length was limited and the antegrade blood flow through the other limb remained during internal trapping for the dissected VA fenestration limb; therefore careful observation of the blood flow to the dissected segment after embolization is necessary.

Two Patients Who Underwent Emergency Stenting for Iatrogenic Cervical Internal Carotid Artery Dissection during Thrombectomy.

Objective: Iatrogenic artery dissection during reperfusion therapy is one of the complications causing a poor prognosis. We report two cases of emergent stent placement for iatrogenic cervical carotid artery dissection during reperfusion therapy for acute ischemic stroke. Case Presentation: Two patients, a 77-year-old woman and a 77-year-old man, were diagnosed with acute major cerebral artery occlusion, and underwent reperfusion therapy. The iatrogenic internal carotid artery dissection was caused by derivation of a 6-Fr catheter and 0.014-inch wire in the tortuous cervical internal carotid artery, and emergent stent placement was performed. Recanalization was confirmed and no deterioration caused by the iatrogenic dissection was found. Conclusion: In patients in whom cerebral infarction is localized on MRI, additional stent placement may be effective for preventing adverse events caused by iatrogenic cervical internal carotid artery dissection during reperfusion therapy for intracranial cerebral artery occlusion related to atherosclerotic change.

A Patient with a Large Basilar Artery Aneurysm in Whom Coil Embolization Was Performed by Protruding an LVIS into the Aneurysmal Neck in a Barrel-like Shape and Preserving a Branch Vessel.

Objective: We report a case of a low-profile visualized intraluminal support device (LVIS) being deployed and protruded into an aneurysmal neck in a barrel-like shape to perform dense coil embolization while preserving the branch vessel from the aneurysmal dome in order to prevent aneurysmal enlargement. Case Presentation: A 74-year-old woman had a recurrent large cerebral aneurysm at the bifurcation of the basilar artery and the left superior cerebellar artery (SCA). Therefore, an LVIS was deployed from the left posterior cerebral artery to the basilar artery and protruded into the aneurysmal neck in a barrel-like shape to increase its metal coverage ratio. As the barrel-shaped protruding LVIS served as a scaffold to support the coils, dense coil embolization was performed while preserving the SCA branching from the aneurysmal dome. Images obtained at 6 months and 1 year after the embolization confirmed preservation of the SCA and prevention of aneurysmal enlargement. Conclusion: Protruding the LVIS into an aneurysmal neck in a barrel-like shape is a technique that may help preserve the branch vessel and facilitate dense coil embolization.

A Survived Case of Acute Bilateral Internal Carotid Artery Occlusion Treated by Mechanical Thrombectomy.

Objective: We report a survived case of acute bilateral internal carotid artery occlusion successfully treated by mechanical thrombectomy. Case Presentation: The patient was an 82-year-old right-handed man. Sudden consciousness disturbance and aphasia appeared, and cranial magnetic resonance angiography (MRA) revealed bilateral internal carotid artery occlusion. Cerebral angiography demonstrated occlusion between the cervical and cavernous portions of the bilateral internal carotid artery, and the growth of collateral circulation to the areas where the bilateral internal carotid artery perfused. We performed mechanical thrombectomy first on the left side, which was the main cause of his symptoms and relatively wide ischemic penumbra, and achieved recanalization of the bilateral internal carotid artery and suppressed extensive enlargement of the infarction. Conclusion: Acute bilateral internal carotid artery occlusion requires an optimal treatment strategy based on the clinical symptoms and preoperative imaging.

Occipital Sinus Dural Arteriovenous Fistula Presenting with Cerebellar Hemorrhage.

BACKGROUND: Occipital sinus (OS) dural arteriovenous fistula (DAVF) is extremely rare, and we are aware of no case accompanied by cerebral hemorrhage. We present a case of OS DAVF presenting with cerebellar hemorrhage, treated successfully by transvenous embolization. CASE DESCRIPTION: A 62-year-old female presented with headache and nausea of recent onset. Computed tomography revealed left cerebellar hemorrhage with perihematomal edema. Angiography showed OS DAVF fed by bilateral occipital and posterior meningeal arteries, with drainage into the left inferior hemispheric vein and right transverse sinus receiving the shunt flow from OS. The caudal side of the OS was occluded. The inferior hemispheric vein was dilated with 2 varices, and the junction between the OS and right transverse sinus was narrowed. Because the OS was not involved in normal cerebellar drainage, transvenous embolization of the OS was performed. The microcatheter was advanced to the OS from the transverse sinus during balloon occlusion at the confluence of sinuses. Coils were placed in the OS from the caudal to cranial side, and complete occlusion of the shunt was obtained. CONCLUSIONS: This is the first report of OS DAVF presenting with cerebellar hemorrhage. Transvenous embolization of the affected OS appears ideal when transvenous access is feasible, and the OS is not involved in normal venous drainage of the cerebellum.

Breakage and Retrieval of an Aspiration Catheter Coil with a Stent Retriever During Mechanical Thrombectomy.

BACKGROUND: Some mechanical thrombectomy techniques for acute ischemic stroke use a combination of an aspiration catheter and stent retriever. We experienced a rare case of aspiration catheter coil breakage and subsequent retrieval using a stent retriever. CASE DESCRIPTION: A 79-year-old man suddenly developed somnolence, global aphasia, and right hemiplegia. Magnetic resonance imaging revealed acute infarction of the left frontal lobe and occlusion of the left common carotid artery. Thus, using an aspiration catheter and a stent retriever, mechanical thrombectomy was performed. The stent retriever was deployed from the middle cerebral artery to the internal carotid artery and retracted into the aspiration catheter placed in the internal carotid artery proximal to the thrombus. The catheter was bent during retraction of the stent retriever. After thrombus aspiration, the internal carotid and anterior and middle cerebral arteries were successfully reperfused; however, the stent retriever captured a broken section of the winding coil of the aspiration catheter. We suspected that an X-ray marker on the stent retriever broke the winding coil at the bent segment of the aspiration catheter and the stent captured the broken coil. CONCLUSIONS: The combined use of an aspiration catheter and a stent retriever may cause unexpected device breakage, especially when the catheter is bent.

Therapeutic effects of combined cell transplantation and locomotor training in rats with brain injury.

Cell-based therapies are attracting attention as alternative therapeutic options for brain damage. In this study, we investigated the therapeutic effect of a combined therapy of cell transplantation and locomotor training by evaluating the neuronal connectivity. We transplanted neural cells derived from the frontal cortex of E14.5 GFP-expressing mice into the frontal lobe of 3-week-old rats with brain injury, followed by treadmill training (TMT) for 14 days. In the TMT(-) group, graft-derived neurites were observed only in the striatum and internal capsule. In contrast, in the TMT(+) group, they were observed in the striatum, internal capsule, and the cerebral peduncle and spinal cord. The length of the longest neurite was significantly longer in the TMT(+) group than in the TMT(-) group. In the TMT(+) group, Synaptophysin+ vesicles on the neuronal fibers around the ipsilateral red nucleus were found, suggesting that neuronal fibers from the grafted cells formed synapses with the host neurons. A functional analysis of motor recovery using the foot fault test showed that, 1 week after the transplantation, the recovery was significantly better in the cell transplantation and TMT group than the cell transplantation only group. The percentage of cells expressing C-FOS was increased in the grafts in the TMT(+) group. In conclusion, TMT promoted neurite extensions from the grafted neural cells, and the combined therapy of cell transplantation and locomotor training might have the potential to promote the functional recovery of rats with brain injury compared to cell transplantation alone.

[Risk Factors for Early Progression of Carotid Stenosis after Cervical Radiation Therapy].

OBJECTIVE: Carotid stenosis may occur as a late complication following cervical radiation therapy(RT);however, it may also progress in the early post-RT period. This study aimed to characterize the clinical features associated with the early progression of post-RT carotid stenosis. METHODS: We retrospectively reviewed clinical records of 30 patients who had undergone unilateral or bilateral cervical RT between January 2010 and November 2014. We analyzed the pre- and post-RT stenosis of their carotid arteries using contrast-enhanced computed tomography images. The arteries were classified as progressive or non-progressive according to the presence or absence of stenosis progression within five years after RT. Using univariate and multivariate analyses, we evaluated the following potential clinical risk factors:age;gender;history of hypertension, hyperlipidemia, diabetes mellitus, coronary artery disease, or smoking habit;antiplatelet or statin use;radiation dose;and prior presence of carotid stenosis before RT. RESULTS: In total, we reviewed 57 irradiated carotid arteries and identified 9 with early post-RT progression. Carotid stenosis before RT was observed in 88.9% of arteries in the progressive group but only 2% of arteries in the non-progressive group and it predicted progression(univariate and multiple logistic regression analyses, p<0.0001). No other clinical characteristics had a significant association with the progression of carotid stenosis. CONCLUSION: Prior presence of carotid stenosis may be a risk factor for its early progression after RT. Pre-RT screening of cervical arteries may be useful, and strict management of carotid stenosis is critical in patients with cervical radiation therapy.

[Therapeutic Effects of Low-Dose Bevacizumab for the Treatment of Recurrent Brain Metastases].

OBJECTIVE: Molecularly targeted therapy has been adopted to treat a number of cancers. Bevacizumab, a recombinant humanized monoclonal antibody against vascular endothelial growth factor, is a representative agent used in molecularly targeted therapeutic regimens. However, the therapeutic effect of bevacizumab for the treatment of brain metastases remains unknown. We report the clinical effects of low dose bevacizumab(≤2.5mg/kg/week)to treat recurrent brain metastases. METHODS: We retrospectively analyzed patients with brain metastases who had been treated with bevacizumab between 2012 and 2016 at our institution. We identified clinical characteristics, including age, gender, primary tumor site, dose of bevacizumab, therapeutic and adverse effects, and magnetic resonance imaging results. The lesions were assessed with the RECIST criteria based on gadolinium-enhanced T1-weighted, T2-weighted, and FLAIR images. Statistical analysis was performed using t-test and Fisher's exact test. RESULTS: The cohort comprised 26 patients(8 men, 18 women)with a median age of 61 years(range 39-82 years). There were no significant clinical differences between the low dose and non-low dose groups. Patients in the low dose group did not report any adverse effects from bevacizumab. Three patients with brain metastases from colon cancer are illustrated to report the clinical course of low dose bevacizumab. CONCLUSION: Low dose bevacizumab may be a safe and effective therapeutic option to treat recurrent brain metastases from bevacizumab-sensitive cancers.

Enhanced Axonal Extension of Subcortical Projection Neurons Isolated from Murine Embryonic Cortex using Neuropilin-1.

The cerebral cortical tissue of murine embryo and pluripotent stem cell (PSC)-derived neurons can survive in the brain and extend axons to the spinal cord. For efficient cell integration to the corticospinal tract (CST) after transplantation, the induction or selection of cortical motor neurons is important. However, precise information about the appropriate cell population remains unclear. To address this issue, we isolated cells expressing Neuropilin-1 (NRP1), a major axon guidance molecule receptor during the early developmental stage, from E14.5 mouse embryonic frontal cortex by fluorescence-activated cell sorting. Aggregates of NRP1+ cells gradually expressed subcortical projection neuron markers, Ctip2 and VGluT1, and axon guidance molecule receptors, Robo1 and deleted in colorectal calcinoma (Dcc), in vitro, suggesting that they contained early-stage subcortical projection neurons. We transplanted NRP1+ cells into the frontal cortex of P2 neonatal mice. Compared with grafts derived from NRP1- or unsorted cells, those derived from NRP1+ cells extended a larger number of axons to the spinal cord along the CST. Our data suggest that sorting NRP1+ cells from the embryonic cerebral cortex enriches subcortical projection neurons to reconstruct the CST.

Extracranial internal carotid artery dissection caused by compression from a giant osteophyte due to atlantoaxial osteoarthritis: case report.

Deformed osseous structures have been reported as rare causes of extracranial internal carotid artery (ICA) dissection, including the styloid process and the hyoid bone. Here, the authors describe the first known case of symptomatic ICA dissection caused by a giant osteophyte due to atlantoaxial osteoarthritis. The left ICA was fixed at the skull base and at the ICA portion compressed by the osteophyte, and it was highly stretched and injured between the two portions during neck rotation. The patient was successfully treated with ligation of the affected ICA following balloon test occlusion. Atlantoaxial osteoarthritis should be considered in the differential diagnosis of ICA dissection in patients with a severely deformed cervical spine.

Intraoperative Transcranial Motor-Evoked Potentials Predict Motor Function Outcome in Intracerebral Hemorrhage Surgery.

OBJECTIVE: Prediction of motor function after intracerebral hemorrhage (ICH) often poses a diagnostic challenge. This study was performed to investigate whether intraoperative monitoring of motor-evoked potentials (MEPs) could predict postoperative motor function recovery. METHODS: We reviewed 16 consecutive patients undergoing evacuation of supratentorial ICH with hemiplegia between June 2011 and October 2014. Patients were categorized according to the results of MEPs before and after evacuation of hematoma. The correlation between detection of MEPs and prognosis of motor function was analyzed. RESULTS: In 10 of 16 cases (62%), stable MEPs were detected before and after evacuation of hematoma, and postoperative motor function was improved in all cases, including 3 cases with severe preoperative motor impairment on manual muscle test (1-2). In 3 cases (19%) in which MEPs were not detected throughout the procedure, motor function was not improved. In the other 3 cases (19%), MEPs were not measured before evacuation of ICH but were detected after evacuation despite poor prognosis of motor function. The results of postevacuation MEPs were considered false-negative results. Predictions using pre-evacuation MEP results were completely consistent with prognosis for recovery, whereas MEPs obtained during and after evaluation were useful for monitoring. CONCLUSIONS: Intraoperative MEPs may indicate preservation of pyramidal tracts, and pre-evacuation MEPs can predict motor function outcome after ICH surgery.

Relationship between histologic features and outcomes of carotid revascularization for radiation-induced stenosis.

OBJECTIVE: This study aimed to elucidate the relationships between preoperative carotid imaging results, histologic characteristics, and surgical treatment outcomes of radiation-induced carotid stenosis (RICS), using control subjects without RICS for comparison. METHODS: We retrospectively reviewed records of 17 patients who underwent carotid revascularization for 22 instances of RICS, including 10 cases of carotid artery stenting (CAS), 11 cases of carotid endarterectomy (CEA), and 1 case of CEA with retrograde CAS, between July 2004 and April 2013. The controls were 475 patients with no history of radiation therapy who underwent carotid revascularization in a similar period. Preoperative magnetic resonance imaging (MRI), ultrasonography (US), and computed tomography angiography results were correlated with outcomes of histologic analysis of CEA specimens. End points included ipsilateral and contralateral stroke, myocardial infarction, restenosis, in-stent thrombosis, and target lesion revascularization. RESULTS: Vulnerable plaques on carotid MRI (86% vs 64.2%; P = .010) and mobile (27% vs 8.0%; P = .008) and ulcerative (50% vs 15.8%; P < .001) plaques on US were more frequent in the RICS group. All revascularization procedures were successful, and no occlusion occurred. Adverse events in the CAS group, including one minor stroke and one transient ischemic attack within 30 days as well as five ipsilateral neurologic events after 30 days, including three minor strokes and two transient ischemic attacks, were significantly more frequent than in the CEA group. All three cases of late ipsilateral stroke displayed vulnerable plaque on preoperative MRI and late in-stent thrombosis or restenosis on US. CONCLUSIONS: Our radiologic and histologic analyses revealed that advanced RICS is often accompanied by formation of vulnerable plaque. CEA can prevent undesirable late outcomes in such cases.