Anatomy and clinical application of suprascapular nerve to accessory nerve transfer.

BACKGROUND: Loss of motor function in the trapezius muscle is one complication of radical neck dissection after cutting the accessory nerve (AN) during surgery. Nerve repair is an effective method to restore trapezius muscle function, and includes neurolysis, direct suture, and nerve grafting. The suprascapular nerve (SCN) and AN are next to each other in position. The function of the AN and SCN in shoulder elevation and abduction movement is synergistic. SCN might be considered by surgeons for AN reanimation. AIM: To obtain anatomical and clinical data for partial suprascapular nerve-to-AN transfer. METHODS: Ten sides of cadavers perfused with formalin were obtained from the Department of Human Anatomy, Histology and Embryology, Peking University Health Science Center. The SCN (n = 10) and AN (n = 10) were carefully dissected in the posterior triangle of the neck, and the trapezius muscle was dissected to fully display the accessory nerve. The length of the SCN from the origin of the brachial plexus (a point) to the scapular notch (b point) and the distance of the SCN from the origin point (a point) to the point (c point) where the AN entered the border of the trapezius muscle were measured. The length and branches of the AN in the trapezius muscle were measured. A female patient aged 55 years underwent surgery for partial SCN to AN transfer at Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The patient suffered from recurrent upper gingival cancer. Radical neck dissection was performed on the right side, and the right AN was removed at the intersection between the nerve and the posterior border of the SCM muscle. One-third of the diameter of the SCN was cut off, and combined epineurial and perineurial sutures were applied between the distal end of the cut-off fascicles of the SCN and the proximal end of the AN without tension. Both subjective and objective evaluations were performed before, three months after, and nine months after surgery. For the subjective evaluation, the questionnaire included the Neck Dissection Impairment Index (NDII) and the Constant Shoulder Scale. Electromyography was used for the objective examination. Data were analyzed using t tests with SPSS 19.0 software to determine the relationship between the length of the SCN and the linear distance. A P value of < 0.05 was considered as statistically significant. RESULTS: The whole length of the AN in the trapezius muscle was 16.89 cm. The average numbers of branches distributed in the descending, horizontal and ascending portions were 3.8, 2.6 and 2.2, respectively. The diameter of the AN was 1.94 mm at the anterior border of the trapezius. The length of the suprascapular nerve from the origin of the brachial plexus to the scapular notch was longer than the distance of the suprascapular nerve from the origin point to the point where the accessory nerve entered the upper edge of the trapezius muscle. The amplitude of trapezius muscle electromyography indicated that both the horizontal and ascending portions of the trapezius muscle on the right side had better function than the left side nine months after surgery. The results showed that the right-sided supraspinatus and infraspinatus muscles did not lose more function than the left side. CONCLUSION: Based on anatomical data and clinical application, partial suprascapular nerve-to-AN transfer could be achieved and may improve innervation of the affected trapezius muscle after radical neck dissection.

Evolution of transmaxillary approach to tumors in pterygopalatine fossa and infratemporal fossa: anatomic simulation and clinical practice.

BACKGROUND: The endoscopic transnasal approach has been proven to have advantages on the removal of the tumors in pterygopalatine fossa (PPF) and infratemporal fossa (ITF). Herein, this study aimed to describe a modified approach for resection of the tumors in these areas, both in cadaveric specimen and clinical patients. METHODS: The 20 adult cadaveric specimens and five patients with tumors in PPF and ITF were enrolled in this study. For the cadaveric specimens, ten were simulated anterior transmaxillary approach and ten were performed modified endoscopic transnasal transmaxillary approach. The exposure areas were compared between two groups and main anatomic structure were measured. Surgery was operated in the five patients with tumors of PPF and ITF to verify the experience from the anatomy. Perioperative management, intraoperative findings and postoperative complications were recorded and analyzed. RESULTS: The modified endoscopic transnasal transmaxillary approach provided as enough surgical exposure and high operability to the PPF and ITF as the anterior transmaxillary approach did. The diameter of maxillary artery in the PPF was 3.77 ±â€Š0.78 mm (range: 2.06-4.82 mm), the diameter of middle meningeal artery in the ITF was 2.79 ±â€Š0.61 mm (range: 1.54-3.78 mm). Four patients who suffered schwannoma got total removal and one of adenocystic carcinoma got subtotal removal. The main complications were facial numbness and pericoronitis of the wisdom tooth. No permanent complication was found. CONCLUSIONS: With the widespread use of neuroendoscopy, the modified endoscopic transnasal transmaxillary approach is feasible and effective for the resection of tumors located in PPF and ITF, which has significant advantages on less trauma and complications to the patients.

125 I interstitial brachytherapy in management of pediatric skull base tumors.

BACKGROUND: The purpose of this study was to present our preliminary assessment of the safety and efficacy of 125 I interstitial brachytherapy (IBT) in the management of pediatric skull base tumors. METHODS: Thirty pediatric patients with skull base tumors treated with 125 I IBT from April 2007 to May 2017 were included in this study. The probabilities of local control (LC) and overall survival (OS) were calculated by the Kaplan-Meier method. RESULTS: The one- and two-year LC rates were 96.7% and 74.8%, respectively. The one- and two-year OS rates were 93.3% and 72.2%, respectively. No severe acute toxicity was observed. Severe late toxicities were observed in one (3.33%) of 30 patients. CONCLUSION: 125 I IBT is effective and safe in the management of pediatric skull base tumors, with satisfactory cosmetic and functional outcomes.

[Application of superficial temporal artery to middle cerebral artery bypass in treatment of cerebral artery steno-occlusive disease].

OBJECTIVE: To explore the effect of superficial temporal artery to middle cerebral artery(STA-MCA) bypass in treatment of cerebrovascular disease. METHODS: Fifty-two patients with atherosclerotic carotid artery occlusion or middle cerebral artery occlusion or moyamoya disease were included in this study. There were both clinical ischemic manifestation and hemodynamic dysfunction detected by perfusion CT in all the patients. DSA and perfusion CT (PCT) were conducted before and after STA-MCA bypass in order to evaluate the change of hemodynamics and the state of anastomotic astium. The patients were followed-up to know if there was any complication or recurrent stroke. Modified Rankin scale (mRS) was used in assessing the state of neurological function. RESULTS: STA-MCA bypass was performed successfully in 50 patients, while anastomotic astium was found to be obstructed in 2 patients during operation and temporalis attachment was conducted immediately. Complications occurred in 4 patients, 2 with subdural hematoma, 1 with hematoma in contralateral basal ganglia, and 1 with poor wound healing. Postoperative DSA showed that anastomotic astium was opened well in 48 patients, while PCT displayed a significant improvement in both relative cerebral blood flow [rCBF,(37.79±9.76)mL/(min×100 g)vs.( 33.71±7.92)mL/(min×100 g),P<0.05] and the relative mean transmit time [rMTT,(8.49±1.97)s vs. (11.06±3.00)s,P<0.01]. mRS improved significantly in both the 3 month and 12 month follow-ups(1.37±0.66 vs. 1.58±0.64, 0.84±0.57 vs. 1.51±0.67,P<0.05). There was no ipsilateral stroke during the follow-up. CONCLUSION: STA-MCA bypass may improve the hemodynamic and neurological condition and prevent the recurrence of ischemic stroke in patients combined with occlusive cerebrovascular disease and hemodynamic disturbance.

Virtual reality system for diagnosis and therapeutic planning of cerebral aneurysms.

BACKGROUND: The virtual reality (VR) system can provide the neurosurgeon to intuitively interact with and manipulate the three dimensional (3-D) image similarly to manipulate a real object. It was seldom reported that the system was used in diagnosis and treatment of cerebral aneurysms. This study aimed to investigate the application of VR system in diagnosis and therapeutic planning of cerebral aneurysms. METHODS: A total of 24 cases of cerebral aneurysms were enrolled in this study from 2006 to 2008, which diagnosed by 3-D digital subtraction angiography (3D-DSA) or VR-based computed tomography angiographies (CTA). The VR system and 3D-DSA system were used to observe and measure aneurysms and the adjacent vessels. The data of observation and measurements were compared between VR image and 3D-DSA image. All the patients underwent surgical plan and simulated neurosurgical procedures in the VR system. RESULTS: There were 28 aneurysms detected in VR system and 3D-DSA system. The VR system generated clear and vivid 3-D virtual images which clearly displayed the location and size of the aneurysms and their precise anatomical spatial relations to the parent arteries and skull. The location, size and shape of the aneurysms and their anatomical relationship with the adjacent vessels were similar between 3-D virtual image and 3D-DSA, but the spatial relationship between aneurysms and skull only been displayed by VR system. This VR system also could simulate simple surgical procedures and surgical environments. CONCLUSIONS: The VR system can provide a highly effective way to provide precise imaging details as same as 3D-DSA system and assist the diagnosis of cerebral aneurysms with virtual 3-D data based on CTA. It significantly enhances the chosen therapeutic strategy of cerebral aneurysms.

[Genetic characteristics of HIV-1 CRF01_AE strains in four provinces, southern China].

OBJECTIVE: To analyze the genetic characteristics of HIV-1 CRF01_AE strains prevailing in the four provinces of southern China. METHODS: Plasma samples were collected from the newly diagnosed HIV-1 individuals reported in 2006 in Guangdong, Guangxi, Jiangxi and Hunan province. The gag and env gene fragments were amplified from RNA template extracted from plasma using RT and nested PCR methods. CRF01_AE sequences were analyzed by phylogenetic methods and characterized by calculating the genetic distance and Entropy analysis. RESULTS: Two main epidemic clusters were found to exist in the CRF01_AE strains from 210 HIV-1 CRF01_ AE infected individuals collected in the 4 provinces, southern China. It was found that no international reference strain was closely correlated with cluster I, which including 123 samples. The strains in cluster II, consisting 57 cases of samples, were closely related with the strains identified in Vietnam. Genetic distance analysis of gag and env genes showed that the diversity of cluster I was obviously less than that of cluster II. Data on nucleotide polymorphism showed that nucleotides compositions of 42 sites in gag and 40 sites in env were significantly different between the two clusters. When compared with cluster II, the polymorphism decreased at 61 nucleotide sites but increased at 21 sites in cluster I. CONCLUSION: This was the first report describing that two main epidemic clusters were existed in CRF01_AE strains prevailing in the 4 provinces, Southern China. The virus in cluster I was the dominant strain in this region, with shorter period of circulation and higher proportion seen in the HIV-infected population, which might belong to CRF01_AE strain with certain features facilitating the spread of the virus. The virus in cluster II was highly homology with the CRF01_AE strains from Vietnam, and seemed to have had several events of epidemics in populations in border regions of China and Vietnam.

[HIV-1 molecular epidemiological survey of drug users in Jiangxi province].

OBJECTIVE: To investigate HIV-1 molecular epidemiology of drug users in Jiangxi Province to analyze epidemic situation, subtype, origin of strain, and variation, and to provide information for prevention and control of AIDS. METHODS: Combining principles of traditional epidemiology and molecular epidemiology, the authors analyzed the epidemiologically related factors, the gene sequences and systematic mutation of HIV-1 gene in nine drug users in Jiangxi province. RESULTS: The HIV spread through the drug users in Jiangxi not only by injection but also by sexual contacts. The main epidemic strain found by sequence analysis was HIV-1 CRF01-AE that was closely related to the strain among drug users in Vietnam and Guangxi Zhuang Autonomous Region, with the average gene distance of 9.00 +/- 2.27 from the Vietnam strain. The origin of strain among drug users in the province was entirely the same. CONCLUSION: At present, HIV-1 CRF01-AE strain has spread in the whole province among the drug users. Vigorous behavioral interventions should be developed in drug users and un-safe sexual behavior population to prevent the epidemic.