There has been no consensus on the efficacy of extracranial-intracranial arterial bypass (EIAB) for ischemic cerebrovascular disease. As an important factor in the pathophysiologic mechanisms of ischemic cerebrovascular disease, the changes of cerebral hemodynamics have received attention. The article expounds the clinical significance of EIAB from the point of view of cerebral hemodynamics, particularly presents its preoperative assessment, operative procedures, and efficacy criterion.

CT perfusion (CTP) has provide a novel approach for the diagnosis of ischemic cerebrovascular diseases. The evaluation indices include cerebral blood flow, cerebral blood volume, time to peak, and mean transmit time. These semi-quantitative indices used for evaluating cerebral blood perfusion have very important significance for the guidance of choosing the best treatment protocol and efficacy observation. CTP is mainly used in acute ischemic stroke to identify penumbra and infarct, as well as predicting hemorrhagic transformation in combination with other means and choosing thrombolytic candidates. In addition, CTP is also used to assess cerebrovascular reserve capacity in patients with chronic ischemic diseases and diagnose cerebral vasospasm in patients with subarachnoid hemorrhage and their efficacy evaluation.

Extracranial-intracranial arterial bypass, an elegant procedure, was first performed and developed gradually by M. Gazi Yasargil. It has been used in the management of ischemic cerebrovascular disease, moyamoya disease, intracranial aneurysms and brain tumors.This article focuses on its application in the ischemic cerebrovascular disease, and reviews it from the aspects of cerebral hemodynamics of ischemic cerebrovascular disease, indications for arterial bypass, preoperative evaluation, operating modes, intraoperative assessment,complications, postoperative care and prognosis.

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Objective To preliminarily discuss the technical points and clinical efficacy of the pressure cooker technique (PCT)for embolization of intracranial arteriovenous malformation (AVM). Methods From April 2015 to May 2015,7 patients with AVM were treated at the Department of Neurosurgery, Shanghai Deji Hospital. The AVMs of 2 patients were embolized with PCT. (both were Spetzler-Martin gradeⅡ). A sonic and an echelon microcatheter were implanted side by side into the same blood supply artery of an AVM. A coil + α-isobutyl cyanoacrylate (NBCA)plug was formed between the sonic microcatheter tip and the detachable point through the echelon microcatheter in order to prevent Onyx reflux when the glue was injected into a nidus via a sonic microcatheter,achieving the embolization effect of sustained,rapid and high efficient. Results Two patients achieved complete embolization immediately. The symptoms of the patients improved or disappeared within 1 month. The whole brain DSA showed the AVM of one patient did not have recurrence at 4 month after embolization. Two patients did not have any complications or sequelae at the follow-up study. Conclusion PCT can improve the efficiency of embolization. It is suitable for small, medium,superficial,non-major functional area,less feeding artery AVMs,and AVMs with less blood flow in nidus. Its safety and clinical effect still need to be observed with more samples.

Objective Study the diagnostic value of CT to assess the transfer of right recurrent nerve nodes(RRNN) on the thoracic esophageal squamous carcinoma,so as to provide reference for thoracic segment esophageal surgery way.Methods A retrospective analysis from January 2011 to February 2014 in the first affiliated hospital of zhengzhou university at the records of 132 cases of thoracic segment esophageal thoracic surgery with preoperative CT image data,recorded each patient's right recurrent nerve nodes in the largest length to diameter and the average CT number,and compared with postoperative pathologic results.Results With the ROC curve analysis,considering transfer when the length of RRNN' s diameter 8.5 mm or more in CT,the area under the curve is 0.911,the sensitivity is 85.7％,specificity is 78.8％.Considering transfer when the RRNN average CT number acuity 32.50 HU,the area under the curve is 0.815,the sensitivity is 85.7％,specificity is 76.9％.Whether RRNN transfer has significant correlation(P ＜ 0.05) with the length of tumor,tumor location and whether lymph node of other station transfer,doesn' t have significant correlation (P ＞ 0.05)with patients'age,sex,tumor differentiation degree and the T stage.Conclusion When the RRNN length to diameter 8.5 mm or RRNN average CT numberr acuity 32.50 HU,right recurrent nerve nodes should be considered lymph node metastasis,and choose chest conclusion laparoscopic radical prostatectomy.The upper thoracic portion esophageal tumor's length is 5 cm or more,or clinical suspected lymph node metastasis of other station is the risk factor for metastasis of RRNN.

Objective To explore the feasibility of 256-slice whole-brain CT perfusion (CTP) in evaluate graft reperfusion after surgical revascularization and hemodynamic alterations before and after surgery in Moyamoya disease. Methods Twenty-five cases with Moyamoya disease were scanned on a 256-slice CT.CTP was performed pre- and post- surgical revascularization. The wolumetric CT angiographic ( CTA ) images were generated from volumetric data acquired at the arterial phase of CTP. CBF, CBV, TTP and MTT were measured in functional maps at the operated side within middle cerebral artery perfusion areas and contralateral mirroring areas. Relative CBF( rCBF), relative CBV (rCBV), relative TTP (rTTP), relative MTT (rMTT) were also obtained. Differences in perfusion CT values pre- and post operation were assessed with the paired t test or matched-pairs signed-ranks test. Data with normal distribution was present as : (x-)± s,while those with the non-normal distribution were present as M ( P25-P75 ). Results All the direct graft patencies were displayed on volumetric CTA. No significant differences were found between volumetric CTA and conventional CTA. Postoperative CBF, rCBF and rCBV values of the operated side [ 72. 86 (55.54-112. 19) ml · 100 g-1 · min-1 , 1. 31 ( 1.05-1.73), 1.45 ±0. 62] were significantly higher than those before operation [46.72(28.57-57.67) ml · 100 g-1 · min-1, 0.53(0.33-0.82), 1.01 ±0.36](Z=- 2.72, - 2. 98, t = - 2. 85, P ＜ 0. 05 ). Postoperative MTT, TTP and rTTP values of the operated side [ (3.98 ± 2. 36 ) s, ( 17.56 ± 4. 38 ) s, 1.01 ± 0. 09 ] were significantly lower than those before operation [(5.43±2.07) s,(19.40±3.87) s,1.14±0.28] (t=2.41,2.17,2.17, respectively, P＜0.05).However, no significant differences were detected for changes of CBV and rMTT after revascularization ( P ＞0. 05). Conclusion 256-slice CT has the potential value for the non-invasive assessment of both the graft patency and cerebral hemodynamics changes in moyamoya disease after surgery with administration of one contrast medium bolus in a single examination.

Objective To compare the efficacy and cost of surgical clipping and endovascular embolization in the treatment of anterior and posterior communicating artery aneurysm and to conduct cost-effectiveness analysis. Methods The data of treatment outcomes and costs in patients with anterior or posterior communicating artery aneurysms admitted to Huashan hospital from 2002 to 2006 were analyzed using a retrospective cohort study. Results A total of 302 patients were included in the study. They were divided into surgical clipping group (n = 150; 65 males, age [48. 11 ±9. 94] years), interventional treatment group (n = 152;75 males, age [52. 56 ± 11. 09] year). The age of the former was lower than that of the latter (t = -3. 670, P =0. 000). There was no significant difference in preoperative clinical conditions (such as location of aneurysms and Hunt-Hess grade) between the two groups. The good outcome rate in the interventional treatment group was significantly higher than that in the surgical clipping group (84. 87% vs. 74. 67%, χ2 = 4. 875, P = 0. 027). There was no significant difference in hospital mortality (5. 33% vs. 3. 94%,χ2 =0. 328, P =0. 567) and complication rate (26.67% vs. 19. 74% , χ2 =2.036, P =0.154) between the surgical clipping group and the interventional treatment group, but the intraoperative aneurysm rupture (10. 67% vs. 3. 95%, χ2 =5.047, P =0.028) and the incidence of postoperative intracranial infection (6/144 vs. 0/152, χ2 = 6.203, P =0.014) in the surgical clipping group were higher than those in the interventional treatment group. The length of hospital stay in the interventional treatment group was significantly shorter than that in the surgical clipping group ([10. 0 ± 7. 0] dvs. [23.0 ± 11. 0] d, Z = -10. 35, P ＜0.001). The median cost of treatment was 95 327.63 %,yuan in the interventional treatment group, and the interquartile range (IQR) was 26 312. 98 yuan; it was significantly higher than the surgical clipping group (median 30 072. 01 yuan, IQR 11 178. 54 yuan) (Z = -14.449, P＜0.001). Compared with the surgical clipping group, while the mRS score improved in the interventional treatment group 0. 10, the cost was about 66 438 yuan, so that the surgical clipping was more cost-effective. Conclusions The efficacy of the intervention treatment of anterior and posterior communicating artery aneurysms is better than that of the surgical clipping The mortality and total complication rate are almost the same with the surgical clipping Thehospital stay is shorter, but the cost of treatment is higher. From an economic point of view, the surgical clipping is more cost-effective.

OBJECTIVETo investigate the biomechanical characters of human dura and its substitutes and to establish guidelines for selection of optimal repair materials for reconstruction of skull base defects.

METHODSA measurement of creep properties of human dura and its substitutes were conducted using biomechanical tests. The dynamic changes of biomechanical properties of canine dura obtained from skull base defects were observed as well.

RESULTSThe creep properties of human dura presented a linear-relationship between initial strain and stress, and the creep strain increased slowly with time. The creep compliance formula for human dura and its substitutes was as follows: J (t) = J(0) + Kf (t). The initial compliance of canine dura in skull base defects was reduced by 35%, 46% and 50%, respectively 1, 3 and 6 months after surgery.

CONCLUSIONThe optimal material for the repair of skull base defects can be estimated using creep compliance analysis. The less the compliance, the better the property of anti-protrusion. Fresh human dura is the least compliant and then in increasing order are lyophilized human dura, fresh human pericranium, Terylene and silicon membranes. The pattern of biomechanical characteristics of the dura mater at skull base defects shows that the strain ability of the dura mater decreases distinctly for 1 - 3 months and then remains almost unchanged for 3 - 6 months after surgery.

Animals ; Biomechanical Phenomena ; Dogs ; Dura Mater ; physiology ; Humans ; Skull Base ; surgery

OBJECTIVETo clarify whether it is necessary to reconstruct bone defects at the anterior skull base.

METHODSA long-term follow-up study of 50 patients with anterior skull-base defects in which the dura was reconstructed without bone grafts was conducted. CT and MRI examinations were taken periodically after surgery.

RESULTSThe ordinates of the bone defects averaged 3.5 cm (range, 2 - 6 cm), and the abscissas averaged 2.8 cm (range, 2 - 5 cm). The abscissas of the bone defects measured 2 - 3 cm in 38 patients, 3 - 4 cm in 10 patients, and 4 - 5 cm in 2 patients. The follow-up ranged from 3 months to 5 years (average, 2 years).

CONCLUSIONSAt normal intracranial pressure, if the dura mater is repaired properly at the skull-base defects and reinforced with a pedicled pericranial flap, encephalomeningocele and cerebrospinal fluid (CSF) leakage can be prevented. It may not be necessary to make free bone grafts when the size of the cranial base bone defect is smaller than 4 cm.

Adolescent ; Adult ; Dura Mater ; surgery ; Female ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Reconstructive Surgical Procedures ; methods ; Skull Base ; pathology ; surgery ; Time Factors ; Treatment Outcome