Risk factors for recurrence and retreatment after endovascular treatment of intracranial saccular aneurysm larger than 8 mm.

BACKGROUND: Large intracranial aneurysm is challenging for both surgical and endovascular treatment. High recurrence and retreatment rates are still limitations for endovascular treatment. Analysing risk factors of recurrence after endovascular treatment can be useful for planning future treatment strategies. METHOD: We retrospectively reviewed patients with intracranial saccular aneurysm (≥ 8 mm) who underwent endovascular treatment from 2008 to 2017 at our institution. The demographic features, clinical information and angiographic results were analysed to reveal the risk factors for recurrence and retreatment. Subgroup analysis was performed according to packing density (PD) and stent insertion status. RESULTS: The total recurrence and retreatment rates were 25.7% (44/171) and 10.5% (18/171), respectively. Independent risk factors for recurrence after endovascular treatment were larger aneurysm size (OR 1.32; 95% CI 1.17-1.51; p < 0.001), ruptured status (OR 3.91; 95%CI 1.44-10.90; p = 0.008), initial incomplete occlusion (OR 2.72; 95%CI 1.18-6.41; p = 0.020), and low dome-to-neck ratio (OR 0.61; 95%CI 0.36-0.97; p = 0.047). The recurrence rate for the no-stent with low PD (< 17.5%) group was 50% (14/28); 37.5% (6/16) for stent-assisted coil (SAC) with low PD group, 22.0% (20/91) for no-stent with high PD group and 11.1% (4/36) for SAC with high PD group. CONCLUSION: The independent risk factors for recurrence after endovascular treatment in large (≥ 8 mm) intracranial saccular aneurysm were larger aneurysm size, ruptured status, low dome-to-neck ratio and initial incomplete occlusion state. SAC is a useful method for lowering recurrence after endovascular treatment for relatively large (≥ 8 mm) cerebral aneurysm.

Immediate Postoperative Angiographic Stagnation of Contrast Media and T2-Weighted Magnetic Resonance Imaging Features within Aneurysmal Sac Are Associated with Early Regression of Large or Giant Aneurysm After Flow Diversion Only.

BACKGROUND: We hypothesized that the immediate postoperative imaging features would be associated with early regression of flow-diverted aneurysms. We compared the imaging features from digital subtraction angiography and spin echo T2-weighted magnetic resonance imaging between those with early total regression and partial regression. METHODS: A total of 30 consecutive patients with large and giant aneurysms were treated with pipeline embolization devices and divided into 2 groups according to the follow-up angiographic findings at 3-6 months. Of the 30 patients, 20 had had total or near total regression and 10 had had partial regression of the aneurysmal sac. The baseline characteristics, percent area of stagnated iodine contrast agent on anteroposterior and lateral angiographic views just after installation of the pipeline device, and median, minimal, and 10-percentile signal intensity of the aneurysmal sac on T2-weighted spin echo images 1 day after the procedure were compared between the 2 groups. RESULTS: A comparison of the demographic data between the 2 groups showed no significant differences. The volume of the treated aneurysmal sac also did not differ significantly (2559.28 ± 3021.45 mm3 vs. 2551.76 ± 6550.58 mm3; P = 0.455). The total or near total regression group had a larger percent area of iodine stagnation on the lateral angiographic view compared with the partial regression group (52.26% vs. 23.35%; P = 0.002). The median, minimal, and 10-percentile signal intensity of the volume of interest were higher in the total or near total regression group than in the partial regression group (1.29 vs. 0.93 [P = 0.025]; 0.07 vs. 0.00 [P = 0.042]; 0.57 vs. 0.24 [P = 0.005]). CONCLUSIONS: The percent area of contrast media stagnation on lateral angiograms and the median, minimal, and 10th-percentile signal intensity of the volume of interest of treated aneurysmal sacs on T2-weighted images can be used to predict early regression of aneurysmal sacs.

Comparison of Clinical and Radiologic Outcomes of Diverse Endovascular Treatments in Vertebral Artery Dissecting Aneurysm Involving the Origin of PICA.

OBJECTIVE: To determine clinical and radiologic outcomes of vertebral artery dissecting aneurysms involving posterior inferior cerebellar artery according to different types of endovascular treatment. METHODS: This study included 18 vertebral artery dissecting aneurysms (6 ruptured and 12 unruptured) involving posterior inferior cerebellar artery treated from January 2009 to December 2016. Treatments were multiple stenting, stent-assisted coil embolization, vertebral artery trapping with vertebral artery-posterior inferior cerebellar artery stenting, and Pipeline embolization. Clinical and radiologic information were obtained from retrospective chart review and radiologic review. RESULTS: Subarachnoid hemorrhage was diagnosed initially in 6 of 18 patients, and infarction was diagnosed initially in 2 patients. Multiple stenting was performed in 4 patients, including 1 (25%) who had cerebellar infarction and 1 (25%) who had recurrence. Stent-assisted coil embolization was performed in 8 patients, including 1 (12.5%) who had postoperative cerebellar infarction and 2 (25%) who had recurrence. Vertebral artery trapping with vertebral artery-posterior inferior cerebellar artery stenting was performed in 4 patients, including 1 (25%) who had postoperative cerebellar infarction. There was no recurrence (0%). Pipeline embolization was performed in 2 patients, including 1 (50%) who had recurrence. There was no postoperative infarction (0%). No subarachnoid hemorrhage occurred during follow-up. Deterioration in modified Rankin Scale score was found only in the stent-assisted coil embolization group (1/8; 12.5%). CONCLUSIONS: Vertebral artery trapping with vertebral artery-posterior inferior cerebellar artery stenting showed the lowest rate of aneurysm recurrence with high rate of minor infarction and favorable neurologic outcome. Stent-assisted coil embolization showed high recurrence rates with possible fatal disabling infarction.

Association between morphologic subtypes of vertebral artery dissection and vertebral artery hypoplastic appearance.

OBJECTIVES: The purpose of this study was to evaluate the associations between vertebral artery hypoplasia (VAH) and the morphologic types of spontaneous vertebral artery dissection (sVAD) and to assess the chronological changes of VAH after sVAD. METHODS AND MATERIALS: In this retrospective study, we included 208 patients with 216 sVADs which were diagnosed between January 2003 and June 2017 at two tertiary hospitals. Morphologic types of sVAD were classified into aneurysmal dilatation without stenosis, pearl-and-string appearance, and steno-occlusion without aneurysmal dilatation. Baseline clinical characteristics and sVAD types were compared according to the presence of VAH on initial imaging. For 143 sVAD patients with follow-up imaging available, chronological changes of VAH and their associations with sVAD types were also evaluated. RESULT: VAH was detected in 29 (13.9%) subjects: 18 (8.7%) with ipsilateral VAH and 11 (5.3%) with contralateral VAH to the sVAD site. Primary lesion shape was statistically associated with the presence of VAH (P = 0.001); steno-occlusion without dilatation was more frequently observed in the ipsilateral VAH group (44.4%) than the no-VAH group (20.9%) or contralateral VAH group (0%). Of a total 143 sVAD patients with follow-up imaging available, VAH-like diffuse VA narrowing was newly observed in seven patients and four patients who were initially classified into the VAH group showed their VAH-like appearances resolved. CONCLUSIONS: The presence of VAH may be associated with the morphologic subtype of sVAD and the VA diameter can dynamically change, making it possible for the VAH-like appearance to be induced after a sVAD event.

Combination therapy of human bone marrow-derived mesenchymal stem cells and minocycline improves neuronal function in a rat middle cerebral artery occlusion model.

BACKGROUND: The positive effects of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) and minocycline on ischemic stroke models have been well described through numerous studies. The aim of this study was to evaluate the effectiveness of combination therapy of hBM-MSCs with minocycline in a middle cerebral artery occlusion rat model. METHODS: Forty male Sprague-Dawley rats were enrolled in this study. After right middle cerebral artery occlusion, rats were randomly assigned to one of four groups: control, minocycline, hBM-MSCs, or hBM-MSCs with minocycline. Rotarod test, adhesive-removal test, and modified neurological severity score grading were performed before and 1, 7, 14, 21, and 28 days after right middle cerebral artery occlusion. All rats were sacrificed at day 28. The volume of the infarcted area was measured with triphenyl tetrazolium chloride staining. Neuronal nuclear antigen (NeuN)- and vascular endothelial growth factor (VEGF)-positive cells in the ischemic boundary zone were assessed by immunofluorescence. RESULTS: Neurological outcome in the adhesive-removal test and rotarod test and modified neurological severity score were better in the combination therapy group than in the monotherapy and control groups. The volume of the infarcted area was smaller in the combination group compared with the others. The proportions of NeuN- and VEGF-positive cells in the ischemic boundary were highest in the combination therapy group. CONCLUSIONS: Early combination therapy of hBM-MSCs with minocycline in an ischemic stroke model may enhance neurological recovery, reduce the volume of the infarcted area, and promote the expression of NeuN and VEGF in ischemic boundary cells.

Video-assisted thoracoscopic surgery under O-arm navigation system guidance for the treatment of thoracic disk herniations: surgical techniques and early clinical results.

This study describes the surgical technique and clinical results of video-assisted thoracoscopic surgery (VATS) assisted by an O-arm-based navigation system, used for the treatment of thoracic disk herniation (TDH). The trend toward the use of minimally invasive procedures with endoscopic visualization of the thoracic cavity in thoracic spine surgery has evolved. It is difficult to develop a new set of visuomotor skills unique to endoscopic procedures and understand the three-dimensional (3D) anatomy while performing a two-dimensional (2D) imaging procedure. Adding image guidance would have a positive impact on these procedures, making them safer and more precise. We report the results of 10 patients who underwent diskectomy for TDH using VATS assisted by an O-arm-based navigation system and describe the surgical technique. The average duration of the symptoms was 2.8 years; average operation time, 326.9 minutes; and average additional time required for the image guidance surgery using the O-arm-based navigation, ∼ 29.4 minutes. No complications occurred during the surgical procedure or the immediate postoperative period. The advantages of using navigational assistance during the surgical procedure include better visualization of the operative field, more accurate surgical planning, and optimization of the surgical approach involving the establishment of the correct drilling trajectory and safe decompression of the spinal cord, as well as the possibility of intraoperative control of bone resection.

Sagittal sacropelvic morphology and balance in patients with sacroiliac joint pain following lumbar fusion surgery.

OBJECTIVE: To investigate the sagittal sacropelvic morphology and balance of the patients with SIJ pain following lumbar fusion. METHODS: Among 452 patients who underwent posterior lumbar interbody fusion between June 2009 and January 2013, patients with postoperative SIJ pain, being responded to SIJ block were enrolled. For a control group, patients matched for sex, age group, the number of fused level and fusion to sacrum were randomly selected. Patients were assessed radiologic parameters including lumbar lordosis, pelvic incidence (PI), pelvic tilt (PT) and sacral slope (SS). To evaluate the sagittal sacropelvic morphology and balance, the ratio of PT/PI, SS/PI and PT/SS were analyzed. RESULTS: A total of 28 patients with SIJ pain and 56 patients without SIJ pain were assessed. Postoperatively, SIJ pain group showed significantly greater PT (p=0.02) than non-SIJ pain group. Postoperatively, PT/PI and SS/PI in SIJ pain group was significantly greater and smaller than those in non-SIJ pain group respectively (p=0.03, 0.02, respectively) except for PT/SS (p=0.05). SIJ pain group did not show significant postoperative changes of PT/PI and SS/PI (p=0.09 and 0.08, respectively) while non-SIJ pain group showed significantly decrease of PT/PI (p=0.00) and increase of SS/PI (p=0.00). CONCLUSION: This study presents different sagittal sacropelvic morphology and balance between the patients with/without SIJ pain following lumbar fusion surgery. The patients with SIJ pain showed retroversed pelvis and vertical sacrum while the patients without SIJ pain have similar morphologic features with asymptomatic populations in the literature.

Cystic giant sacral schwannoma mimicking aneurysmal bone cyst : a case report and review of literatures.

To present a rare case of a cystic giant schwannoma of the sacrum mimicking aneurysmal bone cyst (ABC). A 54-year-old man visited our institute complaining left leg weakness and sensory change for several years. Magnetic resonance imaging revealed a large multilocular cystic mass with canal invasion and bone erosion confined to left S1 body. The lesion showed multiple septal enhancement without definite solid component. Initially the tumor was considered as ABC. The patient underwent grossly-total tumor resection with lumbosacral reconstruction via posterior approach. The tumor was proved to be a cystic schwannoma. The postoperative course was uneventful and the patient was relieved from preoperative symptoms. We present a rare case of pure cystic giant schwannoma confined to sacrum mimicking ABC. The surgical treatment is challenging due to the complex anatomy of the sacrum. Schwannoma should be considered in the differential diagnosis of osteolytic sacral cysts.