Learning curve and influencing factors of performing microsurgical anastomosis: a laboratory prospective study.

Despite being a critical component of any cerebrovascular procedure, acquiring skills in microsurgical anastomosis is challenging for trainees. In this context, simulation models, especially laboratory training, enable trainees to master microsurgical techniques before performing real surgeries. The objective of this study was to identify the factors influencing the learning curve of microsurgical training. A prospective observational study was conducted during a 7-month diploma in microsurgical techniques carried out in the anatomy laboratory of the school of surgery. Training focused on end-to-end (ETE) and end-to-side (ETS) anastomoses performed on the abdominal aorta, vena cava, internal carotid and jugular vein, femoral artery and vein, caudal artery, etc. of Wistar strain rats under supervision of 2 expert anatomical trainers. Objective and subjective data were collected after each training session. The 44 microsurgical trainees enrolled in the course performed 1792 anastomoses (1577 ETE, 88%, vs. 215 ETS, 12%). The patency rate of 41% was independent from the trainees' surgical background and previous experience. The dissection and the temporary clamping time both significantly decreased over the months (p < 0.001). Technical mistakes were independently associated with thrombosis of the anastomoses, as assessed by the technical mistakes score (p < 0.01). The training duration (in weeks) at time of each anastomosis was the only significant predictor of permeability (p < 0.001). Training duration and technical mistakes constituted the two major factors driving the learning curve. Future studies should try and investigate other factors (such as access to wet laboratory, dedicated fellowships, mentoring during early years as junior consultant/attending) influencing the retention of surgical skills for our difficult and challenging discipline.

Human placenta aneurysm model for training neurosurgeons in vascular microsurgery.

BACKGROUND: Neurosurgery, a demanding specialty, involves many microsurgical procedures that require complex skills, including open surgical treatment of intracranial aneurysms. Simulation or practice models may be useful for acquiring these skills before trainees perform surgery on human patients. OBJECTIVE: To describe a human placenta model for the creation and clipping of aneurysms. METHODS: Placental vessels from 40 human placentas that were dimensionally comparable to the sizes of appropriate cerebral vessels were isolated to create aneurysms of different shapes. The placentas were then prepared for vascular microsurgery exercises. Sylvian fissure--like dissection technique and clipping of large- and small-necked aneurysms were practiced on human placentas with and without pulsatile flow. A surgical field designed to resemble a real craniotomy was reproduced in the model. RESULTS: The human placenta has a plethora of vessels that are of the proper dimensions to allow the creation of aneurysms with dome and neck dimensions similar to those of human saccular and fusiform cerebral aneurysms. These anatomic scenarios allowed aneurysm inspection, manipulation, and clipping practice. Technical microsurgical procedures include simulation of sylvian fissure dissection, unruptured aneurysm clipping, ruptured aneurysm clipping, and wrapping; all were reproduced with high fidelity to the haptics of live human surgery. Skill-training exercises realistically reproduced aneurysm clipping. CONCLUSION: Human placenta provides an inexpensive, widely available, convenient biological tissue that can be used to create models of cerebral aneurysms of different morphologies. Neurosurgical trainees may benefit from the preoperative use of a realistic model to gain familiarity and practice with critical surgical techniques for treating aneurysms.

A new expansive two-open-doors laminoplasty for multilevel cervical spondylotic myelopathy: technical report and follow-up results.

UNLABELLED: The laminoplasty technique was devised by Hirabayashi in 1978 for patients diagnosed with multilevel cervical spondylotic myelopathy. OBJECTIVE: To describe an easy modification of Hirabayashi's method and present the clinical and radiological results from a five-year follow-up study. METHOD AND RESULTS: Eighty patients had 5 levels of decompression (C3-C7), 3 patients had 6 levels of decompression (C2-T1) and 3 patients had 4 levels of decompression (C3-C6). Foraminotomies were performed in 23 cases (27%). Following Nurick`s scale, 76 patients (88%) improved, 9 (11%) had the same Nurick grade, and one patient worsened and was advised to undergo another surgical procedure. No deaths were observed. The mean surgery time was 122 min. Radiographic evaluation showed an increase in the mean sagittal diameter from 11.2 mm at pretreatment to 17.3 mm post surgery. There was no significant difference between pretreatment and post-surgery C2-C7 angles. CONCLUSIONS: This two-open-doors laminoplasty technique is safe, easy and effective and can be used as an alternative treatment for cases of multilevel cervical spondylotic myelopathy without instability.

A new expansive two-open-doors laminoplasty for multilevel cervical spondylotic myelopathy: technical report and follow-up results / Nova tecnica de laminoplastia expansiva para tratamento de mielopatia espondilotica cervical: descricao tecnica e resultados de follow-up

The laminoplasty technique was devised by Hirabayashi in 1978 for patients diagnosed with multilevel cervical spondylotic myelopathy. Objective: To describe an easy modification of Hirabayashi’s method and present the clinical and radiological results from a five-year follow-up study. Method and Results: Eighty patients had 5 levels of decompression (C3-C7), 3 patients had 6 levels of decompression (C2-T1) and 3 patients had 4 levels of decompression (C3-C6). Foraminotomies were performed in 23 cases (27%). Following Nurick`s scale, 76 patients (88%) improved, 9 (11%) had the same Nurick grade, and one patient worsened and was advised to undergo another surgical procedure. No deaths were observed. The mean surgery time was 122 min. Radiographic evaluation showed an increase in the mean sagittal diameter from 11.2 mm at pretreatment to 17.3 mm post surgery. There was no significant difference between pretreatment and post-surgery C2-C7 angles. Conclusions: This two-open-doors laminoplasty technique is safe, easy and effective and can be used as an alternative treatment for cases of multilevel cervical spondylotic myelopathy without instability. .

A laminoplastia é técnica clássica descrita por Hirabayashi em 1978 para descompressão do canal cervical sem utilizar prótese. A principal indicação é o tratamento da mielopatia espondilotica cervical sem instabilidade. Objetivo: Descrever modificação simples da técnica de laminoplastia clássica de Hirabayashi com resultados clínicos e radiográficos em 5 anos de acompanhamento. Resultados e Método: Foram acompanhados 86 pacientes. Em 80, foi feita descompressão por laminoplastia em 5 níveis (C3-C7); em 3, descompressão em 6 níveis (C2-T1); em 3, descompressao em 4 níveis (C3-C6). Em 23 casos (27%), foi realizada foraminotomia associada a descompressão medular. O acompanhamento dos pacientes foi feito utilizando a escala de Nurick. Em 76 pacientes (88%) houve melhora do grau de Nurick. Não houve mortalidade associada à técnica. O tempo médio do procedimento cirúrgico foi de 122 minutos. Em relação à avaliação radiográfica, houve aumento do diâmetro sagital médio do canal cervical de 11,2mm para 17,3mm. Não houve diferença estatística do ângulo C2-C7 nas avaliações antes e após o procedimento cirúrgico. Conclusão: A nova técnica de laminoplastia descrita no presente estudo foi segura, de fácil execução, efetiva, não utiliza protese e não há instabilidade do canal cervical. .

Risk factors for infection in external ventricular drains / Fatores de risco para infecção em derivações ventriculares externas

Objective: The present study aims to define the main risk factors for infection in EVD implants performed in a public tertiary hospital in Belo Horizonte, Brazil. Method: The present study performed a retrospective review of 137 cases of EVD implants in 107 patients from January 2006 to December 2008. Of these cases, 25 patients had to be re-operated, totally 141 implanted shunts. Results: Forty-eight (45%) patients were male and 59 (55%) were female. The age ranged from 6 to 86 years of age (52.12 ± 15.51 years). The incidence of EVD-related infection was 32.7%, while the device permanence varied from 2 to 54 days (mean of 10 days). The EVDs that were maintained for more than 9.5 days, as well as the device changes proved to be statistically significant factors for cerebrospinal fluid (CSF) infection (p < 0.001). Antibiotic prophylaxis did not change the infection rate (p = 0.395). Conclusions: Risk factors for EVD infection included a continuing EVD permanence that lasted for more than 9.5 days and device changes. The present study concluded that there is no advantage for antibiotic prophylaxis regarding CSF infection with EVD implants...

Objetivo: Este estudo objetiva avaliar os fatores de risco para infecção em pacientes submetidos a derivações externas em um hospital público terciário de Belo Horizonte. Método: Revisados retrospectivamente 137 prontuários e selecionados 107 pacientes, dos quais 25 foram submetidos a mais de uma DVE, totalizando 141 DVE instaladas no período de janeiro de 2006 a dezembro de 2008. Resultados: Dos 107 pacientes selecionados, 48 (45%) eram do gênero masculino e 59 (55%), do feminino. A idade variou de 6 a 86 anos (média de 52,12 e desvio-padrão de 15,51 anos). Ocorreu infecção em 32,7% dos pacientes (24,8% das DVE ? 35 casos). O número total de dias de DVE variou de 2 a 54 (média de 10 dias) e demonstrou-se que o uso por período maior que 9,5 dias e a troca do sistema apresentaram significância estatística para o desenvolvimento de infecção (p < 0,001). O uso de antibióticos não apresentou efeito protetor (p = 0,395). Conclusões: A troca do sistema e o tempo de permanência da DVE determinaram a ocorrência de infecções, com aumento do risco após o 10º dia de uso e nos pacientes submetidos a duas ou mais DVE. O uso de antibióticos profiláticos não foi significativo para redução de infecção...

Dissector em ângulo reto para descolamento da dura-máter: nota técnica / Right angle dissector for dural dissection: technical note

Propõe-se modificação do clássico dissector para descolamentoda dura-máter que consiste de duas unidades do instrumento fabricadas com extremidades em ângulo reto e de comprimentos progressivos. Esse instrumento permite separar a dura-máter do crânio de forma eficaz e atraumática.

[Trigeminal radiofrequency rhizotomy for the treatment of trigeminal neuralgia: results and technical modification]. / Rizotomia trigeminal por radiofrequência para tratamento da neuralgia do trigêmeo: resultados e modificação técnica.

The purpose of this study was to evaluate the efficacy of radiofrequency trigeminal rhizotomy in treating 135 patients harboring trigeminal neuralgia, and to introduce a technical modification to guide the puncture of the foramen ovale. A hundred and one (74.8%) patients were treated with a single surgical procedure whereas the 34 (25.2%) remaining patients required two procedures. Follow-up ranges from 6 months to 15 years. Pain relief in the immediate postoperative was achieved in 131 (97.0%) patients. After the initial procedure, recurrence happened in 33 (24.5%) patients. The complications included decrease corneal reflex (4.4%), masseter paresis (2.2%), painful dysesthesia (1.5%) and anesthesia dolorosa (0.7%). The radiofrequency trigeminal rizhotomy is a low risk, highly effective and minimally invasive procedure. The use of the computerized tomography guided fluoroscopy turns foramen ovale's puncture easier, fast and precise.

Rizotomia trigeminal por radiofrequência para tratamento da neuralgia do trigêmeo: resultados e modificaçäo técnica / Trigeminal radiofrequency rhizotomy for the treatment of trigeminal neuralgia: results and technical modification

O objetivo deste estudo é avaliar a eficácia da rizotomia trigeminal por radiofrequência no tratamento da neuralgia essencial do trigêmeo em 135 pacientes e propor modificaçäo da técnica para guiar a punçäo do forame oval. Cento e um (74,8 por cento) pacientes foram tratados com apenas um procedimento cirúrgico e os 34 (25,2 por cento) restantes necessitaram dois procedimentos. O tempo de avaliaçäo pós-operatória variou de 6 meses a 15 anos. O alívio das crises de dor no pós-operatório imediato ocorreu em 131 (97,0 por cento) pacientes. Após a realizaçäo do primeiro procedimento, houve recorrência em 33 (24,5 por cento) pacientes. As complicações incluíram diminuiçäo do reflexo corneano (4,4 por cento), paresia do masseter (2,2 por cento), disestesia dolorosa (1,5 por cento) e anestesia dolorosa (0,7 por cento). A rizotomia trigeminal por radiofrequência constitui procedimento minimamente invasivo, de baixo risco e com alta eficácia. O uso da fluoroscopia por tomografia computadorizada torna a punçäo do forame oval mais fácil, rápida e precisa