Chinese Cerebrovascular Neurosurgery Society and Chinese Interventional & Hybrid Operation Society, of Chinese Stroke Association Clinical Practice Guidelines for Management of Brain Arteriovenous Malformations in Eloquent Areas.

Aim: The aim of this guideline is to present current and comprehensive recommendations for the management of brain arteriovenous malformations (bAVMs) located in eloquent areas. Methods: An extended literature search on MEDLINE was performed between Jan 1970 and May 2020. Eloquence-related literature was further screened and interpreted in different subcategories of this guideline. The writing group discussed narrative text and recommendations through group meetings and online video conferences. Recommendations followed the Applying Classification of Recommendations and Level of Evidence proposed by the American Heart Association/American Stroke Association. Prerelease review of the draft guideline was performed by four expert peer reviewers and by the members of Chinese Stroke Association. Results: In total, 809 out of 2,493 publications were identified to be related to eloquent structure or neurological functions of bAVMs. Three-hundred and forty-one publications were comprehensively interpreted and cited by this guideline. Evidence-based guidelines were presented for the clinical evaluation and treatment of bAVMs with eloquence involved. Topics focused on neuroanatomy of activated eloquent structure, functional neuroimaging, neurological assessment, indication, and recommendations of different therapeutic managements. Fifty-nine recommendations were summarized, including 20 in Class I, 30 in Class IIa, 9 in Class IIb, and 2 in Class III. Conclusions: The management of eloquent bAVMs remains challenging. With the evolutionary understanding of eloquent areas, the guideline highlights the assessment of eloquent bAVMs, and a strategy for decision-making in the management of eloquent bAVMs.

Evaluation of a simple off-the-shelf bi-layered vascular scaffold based on poly(L-lactide-co-ε-caprolactone)/silk fibroin in vitro and in vivo.

Purpose: In the field of small-caliber vascular scaffold research, excellent vascular remodeling is the key to ensuring anticoagulant function. We prepared an off-the-shelf bi-layered vascular scaffold with a dense inner layer and a loose outer layer and evaluated its remodeling capabilities by in vivo transplantation. Materials and Methods: Based on poly(L-lactide-co-ε-caprolactone) (PLCL), silk fibroin(SF), and heparin (Hep), PLCL/SF/Hep bi-layered scaffolds and PLCL/Hep bi-layered scaffolds were prepared by electrospinning. The inner layer was a PLCL/SF/Hep or PLCL/Hep nanofiber membrane, and the outer layer was PLCL/SF nano yarn. The in vitro tests included a hydrophilicity test, mechanical properties test, and blood and cell compatibility evaluation. The in vivo evaluation was conducted via single rabbit carotid artery replacement and subsequent examinations, including ultrasound imaging, immunoglobulin assays, and tissue section staining. Results: Compared to the PLCL/Hep nanofiber membrane, the hydrophilicity of the PLCL/SF/Hep nanofiber membrane was significantly improved. The mechanical strength met application requirements. Both the blood and cell compatibility were optimal. Most importantly, the PLCL/SF/Hep scaffolds maintained lumen patency for 3 months after carotid artery transplantation in live rabbits. At the same time, CD31 and α-SMA immunofluorescence staining confirmed bionic endothelial and smooth muscle layers remodeling. Conclusion: Using this hybrid strategy, PLCL and SF were combined to manufacture bi-layered small-caliber vascular scaffolds; these PLCL/SF/Hep scaffolds showed satisfactory vascular remodeling.

Gamma knife radiosurgery for skull base malignancies.

BACKGROUND: Skull base malignancies are problematic. We evaluated the efficacy and toxicity of gamma knife radiosurgery (GKRS) in the treatment of patients with primary and secondary malignancies in the skull base. METHODS: The data of 43 patients were retrospectively analyzed. Sixteen of these patients had a primary skull base malignancy, and 27 patients had skull base metastasis or an invasion from other cancers. The median tumor volume was 7.2 cm(3) (range, 0.6-33.4). The median prescription margin dose was 14.0 Gy (range, 10-16). Nine patients with tumor regrowth after initial reduction received another treatment. RESULTS: The median follow-up time was 14 months (range, 1-60). Following GKRS, the progression-free survival was 89% and 62% at 1 and 2 years, respectively, and the overall survival rate was 74% and 45% at 1 and 2 years, respectively. Nineteen (44%) patients reported an improvement following GKRS. One patient (2%) reported decreased vision, which was considered to be a side effect from cumulative GKRS doses. CONCLUSION: Gamma knife radiosurgery is an effective treatment for primary and secondary malignant tumors in the skull base as initial monotherapy or as an adjunct therapy to surgery or radiotherapy.

Gamma knife radiosurgery for residual skull base chordomas.

OBJECTIVE: The location of chordomas within the base of the skull and cervical junction prevents complete resection from being achieved. Previous series have shown that stereotactic radiosurgery can be used as a treatment for residual chordomas with good overall results. In the present study, we reviewed our experience in using gamma knife surgery (GKS) to treat patients with residual skull base chordomas. METHODS: Thirty-one patients with residual skull base chordomas underwent gamma knife radiosurgery from June 1996 to December 2004. The mean age of patients was 40.2 years (range: 8-70 years). There were 20 male and 11 females. The post-operative tumor volume treated with GKS ranged from 0.47 to 27.6 cm3, with a mean of 11.4+/-7.4 cm3. The mean tumor margin radiation dose was 12.7 Gy (range: 10-16 Gy), and the mean maximum dose was 29.2 Gy (range: 20.8-40 Gy). Twenty-eight patients were available for follow-up reviews, ranging from 6 to 102 months (mean: 30.2 months) and from 6 to 78 months (mean: 28 months), for clinical and image assessments, respectively. RESULTS: Kaplan-Meier survival analysis showed a survival of 90.9 and 75.8% after 3 and 5 years, respectively. Most tumors were smaller in size 1 year after treatment, which paralleled an alleviation of clinical symptoms. However, nine chordomas progressed, and seven recurred over the course of follow-up. The actuarial tumor control rate was 64.2 and 21.4% after 3 and 5 years, respectively. No serious radiation-related complication was found in any of the patients with GKS alone. CONCLUSIONS: Gamma knife radiosurgery can be effectively used for residual chordomas beside surgical resection with efficacious tumor control rates.

Gamma knife radiosurgery for tumors involving the cavernous sinus.

OBJECTIVE: To study the features of diagnosis and radiosurgery of tumors involving the cavernous sinus. METHODS: From December 1994 to the end of 2000, 175 patients with cavernous sinus lesions were treated by Leksell gamma knife (GK) in our Institute. Ninety patients (51.4%) had had open surgery previously. Our experience of treating cavernous sinus tumors by GK was analyzed retrospectively. RESULTS: A Hundred and forty-four (82.3%) patients were followed from 1 to 84 months (median 32.5 months); total tumor control rate was 94%. Surgery was performed after radiosurgery in 3 patients because of tumor enlargement. Metastatic tumor in the cavernous sinus was highly sensitive to irradiation. These lesions shrunk markedly on MRI 2-3 months after GK surgery. The median survival time was 12.2 months, and patients died of noncavernous sinus lesions. CONCLUSION: With high tumor control rate and few complications, GK surgery could become a main option for small benign or residual tumors involving the cavernous sinus. It is also very useful as part of comprehensive therapy for metastatic tumors in the cavernous sinus.

[Surgical management of brain-stem gliomas: a retrospective analysis of 311 cases].

OBJECTIVE: To further study the clinical features, diagnosis, and surgery outcome of brain-stem gliomas. METHODS: Totally 311 patients with brain-stem gliomas received surgery operations in our hospital from 1980 to the end of 2001. The clinical data, neuroimages, growth patterns, and operative feasibility were analyzed. RESULTS: Different brain-stem gliomas showed different growth patterns. In this series, total excision rate of the tumor was 40.5%, subtotal 29.9%, partial 29.6%, and operative mortality 1.3%. Among 311 patients, 72.4% patients had been improved and stable in their symptoms after operation, and 27.6% deteriorated or having transitory new signs. Five years survival rate is 67% in ependymoma patients, 42% in astrocytoma patients. None of brain-stem glioblastoma patients survived up to 5 years. CONCLUSIONS: The histology and growth pattern of brainstem gliomas varies. The patients with well-differentiated gliomas of brain-stem may be cured by microsurgical removal. For malignant ones, partial removal may prolong survival and facilitate the following combined therapy.

[Gamma knife radiosurgery for cavernous malformations].

OBJECTIVE: To evaluate the efficacy of Gamma knife surgery (GKS) in treating cavernous malformation (CM). METHODS: From 1994 to 2001, 92 patients with 114 CMs were treated by GKS and then followed up for 2-8 years (mean 4.1+/-1.9). We analyzed the MRI features of CMs bleeding, efficacy of GKS, and the complications of treatment. Six pathological specimens after radiosurgery (1 from our group, 5 from other centers) were also assayed. RESULTS: Among 43 patients who were treated by GKS to control their epilepsy, epileptic paroxysm was alleviated in 36 patients (83.7%), including 12 (27.9%) seizure-free. Rebleeding was confirmed in 9 patients (9.8%) by neuroimage, one of whom died. Transient symptomatic radiation edema occurred in 7 cases (7.6%) within 6-12 months after radiosurgery, and one patient underwent open surgery for cerebral decompression. The main pathological changes of cavernoma were coagulation necrosis and the vessels obliterated gradually after radiosurgery. CONCLUSIONS: It is feasible to treat small and surgically high risk CMs by radiosurgery. The treatment has to be prudent in an acute bleeding and symptomatic progression. Optimal treatment timing and dose planning are prerequisites to reduce radiation-related complications. GKS is safe and effective to control the epilepsy caused by CMs, and also to bring down the rebleeding rate after a latency interval of several years.

[Efficacy of gamma knife radiosurgery in treatment of growth hormone-secreting pituitary adenoma].

OBJECTIVE: To evaluate the efficacy of gamma knife radiosurgery (GKS) in treatment of growth hormone (GH)-secreting pituitary adenoma. METHODS: 149 patients with GH-secreting pituitary adenoma, 97 males and 52 females, aged 42.8 (12-72 years), with a course of 6-240 months (72.5 months) and with the mean volume of tumor of 2.36 cm(3) (0.11-12.7 cm(3)) were treated by GKS. The mean dose to tumor margin was 20.87 Gy (10-30 Gy). 124 of them were followed up for 30 months (6-72 months). RESULTS: The serum GH returned normal in 74 patients (64.9%) and declined in comparison with the level before radiosurgery in 23 patients (18.5%). The tumor volume was reduced in 84 patients (67.7%) and remained unchanged in 124 patients (32.4%). Ambiopia appeared in one patient. No other complication was found during the follow-up. CONCLUSION: GKS is safe and effective on the treatment of GH-secreting pituitary adenoma.