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Stroke microsurgical cerebrovascular thrombectomy reports are limited, although this technique could be used in many centers as a primary treatment or a salvage intervention option. It requires great ability, so our aim is to describe and validate a stroke microsurgical thrombectomy ex vivo simulator with operative nuances analysis.Human placenta (HP) models simulated middle cerebral artery vessels with intraluminal thrombus to be microsurgically excised. Six neurosurgeons performed 1-mm and 2-mm longitudinal and transverse arteriotomy in different arteries to remove a 1.5-cm length thrombus. Validation through construct validity compared time to complete the task, complete vessel cleaning, vessel manipulation, vessel stenosis, and leakage in both techniques.All 6 HP models reproduced with fidelity stroke microsurgical thrombectomy, so participants completed 24 sessions, 4 for each neurosurgeon on the same model in different arteries. Construct validity highlighted microsurgical technical difficulties with positive results obtained by parameters variation during performance. Transverse arteriotomy with 1-mm length had best results (P0.05) allowing complete thrombus removal, less stenosis, and minor leakage in abbreviated time.A HP simulator can reproduce with high fidelity all stroke microsurgical thrombectomy part tasks. Transverse 1-mm arteriotomy followed by thrombectomy and 2 simple sutures can fulfill all quality assurance aspects in such intervention accordingly to training model, due to easier vessel opening, complete thrombus removal, no stenosis, and faster microsuture.

Computer vision (CV) feedback could be aimed as a constant tutor to guide ones proficiency during microsurgical practice in controlled environments. Five neurosurgeons with different levels of microsurgical expertise performed simulated vessel dissection and micro-suture in an ex vivo model for posterior computer analysis of recorded videos. A computer program called PRIME (Proficiency Index of Microsurgical Education) used in this research recognized color-labeled surgical instruments, from downloading videos into a platform, with a range of motion greater than 3 mm, for objective evaluation of number of right and left hand movements. A proficiency index of 0 to 1 was pre-established in order to evaluate continuous training improvement. PRIME computer program captured all hand movements executed by participants, except for small tremors or inconsistencies that have a range of motion inferior to 3 mm. Number of left and right hand movements were graphically expressed in order to guide more objective and efficacious training for each trainee, without requiring body sensors and cameras around the operating table. Participants with previous microsurgical experience showed improvement from 0.2 to 0.6 (p

Background Cerebrovascular bypass surgical procedures require highly developed dexterity and refined bimanual technical skills. To attain such a level of prowess, neurosurgeons and residents have traditionally relied on “flat” models (without depth of field), such as chicken wings, live rats, silicone vessels, and other materials that stray far from the reality of the operating room, albeit more accessible. We have explored the use of a hybrid ex vivo simulator that takes advantage of the availability of placenta vessels and retains the complexity of surgery performed on a human skull to create a more realistic method for the development of cerebrovascular bypass surgical skills. Methods Twelve ex vivo simulators were constructed using 3 human placentas and 1 synthetic human skull for each. Face, content, construct, and concurrent validity were assessed by 12 neurosurgeons (6 trained vascular surgeons and 6 general neurosurgeons) and compared with those of other bypass models. Results The fidelity grade was ranked as low (Linkert scale score, 1–2), medium (score, 3), and high (score, 4–5). The face and content validity of the model showed high fidelity to superficial temporal artery–middle cerebral artery bypass surgery. Construct validity showed that cerebrovascular neurosurgeons had better performance, and concurrent validity highlighted that all surgical steps were present. Conclusion The simulator was found to have strong face and content, construct, and concurrent validity for microsurgical cerebrovascular training, allowing for simulation of all surgical steps of the bypass procedure. The hybrid simulator seems to be a promising method for shortening the bypass surgery learning curve. However, more studies are required to evaluate the predictive validity of the model.

SUMMARY BACKGROUND The aim of this study was to perform a cross-cultural adaptation of the Objective Structured Assessment of Technical Skill (OSATS) tool into Brazilian Portuguese and to determine its reproducibility and validity in Brasil. METHODS A Brazilian Portuguese version of OSATS was created through a process of translation, back-translation, expert panel evaluation, pilot testing, and then its validation. For the construct and the concurrent validities, twelve participants were divided into a group of six experts and six novices, who had to perform tasks on a simulation model using human placentas. Each participant was filmed, and two blinded raters would then evaluate their performance using the traditional subjective method and then the Brazilian Portuguese version of OSATS. RESULTS The Brazilian Portuguese version of OSATS had the face, content, construct, and concurrent validities achieved. The average experts’ score and standard deviations were 34 and 0.894, respectively, for Judge 1 and 34.33 and 0.816 for Judge 2. In the case of novices, it was 13.33 and 2.388 for Judge 1 and 13.33 and 3.204 for Judge 2. The concordance between the judges was evident, with the Correlation Coefficient (Pearson) of 0.9944 with CI 95% between 0.9797 and 0.9985, with p < 10-10, evidencing the excellent reproducibility of the instrument. CONCLUSION This preliminary study suggests that the Brazilian Portuguese version of OSATS can reliably and validly assess surgical skills in Brasil. RESUMO OBJETIVOS Objetivou-se com este trabalho adaptar transculturalmente o instrumento Objective Structured Assessment of Technical Skill (Osats) para o português-brasileiro e validá-lo no Brasil. MÉTODOS Uma versão em português-brasileiro do Osats foi criada por meio de um processo de tradução, retrotradução, versão consensual por um comitê de especialistas e pré-teste, seguido da etapa de validação. Para validades de constructo e concorrente, foram recrutados 12 participantes da Universidade Federal de Minas Gerais, divididos em um grupo de seis especialistas e um grupo de seis novatos, que tiveram de realizar tarefas em modelos de simulação utilizando placentas humanas. Cada participante foi filmado em anonimato e dois examinadores avaliaram os seus desempenhos usando o método tradicional subjetivo e depois a versão em português-brasileiro do Osats. RESULTADOS A versão em português-brasileiro do Osats alcançou as validades de face, de conteúdo, de constructo e concorrente. A média e o desvio padrão das pontuações atribuídas aos especialistas foram, respectivamente, 34 e 0,894, para o Juiz 1 e 34,33 e 0,816 para o Juiz 2. No caso dos novatos, foram 13,33 e 2,338 para o Juiz 1 e 13,33 e 3,204 para o Juiz 2. O Coeficiente de Correlação (de Pearson) entre os dois juízes foi de 0,9944 com IC 95% entre 0,9797 e 0,9985, com p

The standard treatment for hydranencephaly and maximal hydrocephalus consists of inserting shunts, although complications frequently occur. Choroid plexus cauterization (CPC) is an alternative, but its long-term efficacy and the factors associated with the success and failure of controlling head circumference (HC) are not well defined. This study aims to evaluate the long-term efficacy and factors related to the success rate of CPC in the treatment of hydranencephaly and maximal hydrocephalus. Forty-two children with maximal hydrocephalus and hydranencephaly underwent CPC from 2006 to 2014 and were retrospectively evaluated. Children with less than 3 months of follow-up were excluded. The long-term efficacy and success rate of possible variables (i.e., sex, type of malformation, type of surgery performed, treatment hospital, age, and HC at the time of surgery and birth) were evaluated. Thirty-four children were considered for the effectiveness analysis. Treatment was successful in 24 children (70.6%), and failure occurred in 10 children (29.4%). Failure was detected soon after the endoscopic procedure (average 116 days). There was no difference in effectiveness when comparing the age at the moment of surgery (p = 0.473), type of malformation (p = 1), HC at birth (0.699), and HC at the time of surgery (p = 0.648). The surgical death rate was 7.14%. Endoscopic CPC was a valid procedure used to treat hydranencephaly and maximal hydrocephaly, and it was effective in 70.6% of cases, with an average follow-up period of 32 months. When failures occurred, they occurred early. None of the analyzed variables interfered with the success of the treatment.

Quality assurance (QA) is a way to prevent mistakes in advance. Although it has been previously reported for surgical setup, there is no effective approach for minimizing microsurgical technical errors before an operation is done. Neurosurgery resident operative errors during brain aneurysm surgery could be foreseen by practicing in an ex vivo hybrid simulator with microscopic fluorescein vessel flow image.Five vascular neurosurgeons and 8 junior/senior neurosurgical residents voluntarily joined this research initiative. The following methodology was adopted: 1) Identification of the 7 most-common resident operative performance errors during brain aneurysm surgery; 2) Design of exercises to prevent common mistakes in brain aneurysm microsurgery using a placenta simulator; and 3) Blinded staff neurosurgeon evaluation of resident performance during real brain aneurysm microsurgery.All key steps to perform such intervention were accomplished with a simulator that uses 2 placentas, a synthetic cranium, and microscopic fluorescein vessel flow image. Neurosurgery residents trained in this model had better surgical performance with fewer perioperative mistakes (P0.05). Fine microsurgical dissection of the arachnoid membrane and aneurysm sac were the most commonly improved tasks among the 7 common operative mistakes. Brain parenchyma traction with secondary bleeding was the only error not prevented after previous simulator training.There was a left-shift on the quality assurance line with residents who practiced brain aneurysm microsurgical errors in an ex vivo model. A multicentric prospective study is necessary to confirm the hypothesis that real operative error could be reduced after training in a realistic simulator.

Intracranial-intracranial (IC-IC) bypass surgery involves the use of significant technical bimanual skills. Indications for this procedure are limited, so training in a simulator with brain vessels similarity could maintain microsurgical dexterity. Our goal is to describe the human placenta vascular anatomy to guide IC-IC bypasses apprenticeship.Human placenta vascular anatomy was reported and validated with comparison to brain main vessels after studying the vascular tree of 100 placentas. Five simulated IC-IC bypasses (end to end, end to lateral, lateral to lateral, aneurysm bridge, and aneurysm exiting branch transposition) were developed and construct and concurrent validated. Statistical analysis using the t variance test was performed with a confidence interval of 0.95.A total of 1200 placenta vessels were used for test-retest validation with a reliability index of 0.95. All 100 human placentas were suitable to perform the 5 different bypasses. Construct validity showed a P0.005. Concurrent validity highlighted the technical differences among simulators.An ex vivo bypass model offers great similarity to main brain vessels with the possibility to practice a variety of IC-IC bypass techniques in a single simulator. Placenta vascular anatomy knowledge can improve laboratory microsurgical training.

Introduction Neurosurgery simulation has gained attention recently due to changes in the medical system. First-year neurosurgical residents in low-income countries usually perform their first craniotomy on a real subject. Development of high-fidelity, cheap, and largely available simulators is a challenge in residency training. An original model for the first steps of craniotomy with cerebrospinal fluid leak avoidance practice using a coconut is described. Material and Methods The coconut is a drupe from Cocos nucifera L. (coconut tree). The green coconut has 4 layers, and some similarity can be seen between these layers and the human skull. The materials used in the simulation are the same as those used in the operating room. Procedure The coconut is placed on the head holder support with the face up. The burr holes are made until endocarp is reached. The mesocarp is dissected, and the conductor is passed from one hole to the other with the Gigli saw. The hook handle for the wire saw is positioned, and the mesocarp and endocarp are cut. After sawing the 4 margins, mesocarp is detached from endocarp. Four burr holes are made from endocarp to endosperm. Careful dissection of the endosperm is done, avoiding liquid albumen leak. The Gigli saw is passed through the trephine holes. Hooks are placed, and the endocarp is cut. After cutting the 4 margins, it is dissected from the endosperm and removed. The main goal of the procedure is to remove the endocarp without fluid leakage. Discussion The coconut model for learning the first steps of craniotomy and cerebrospinal fluid leak avoidance has some limitations. It is more realistic while trying to remove the endocarp without damage to the endosperm. It is also cheap and can be widely used in low-income countries. However, the coconut does not have anatomic landmarks. The mesocarp makes the model less realistic because it has fibers that make the procedure more difficult and different from a real craniotomy. Conclusion The model has a potential pedagogic neurosurgical application for freshman residents before they perform a real craniotomy for the first time. Further validity is necessary to confirm this hypothesis.

Lesions located in the bilateral posterior incisural space are difficult to treat due to limited exposure. The classical approaches to this area are limited for lesions located bilaterally and especially when the lesion extends also below the tentorium as it may occur with meningiomas. Kawashima et al. reported, in anatomic studies, a new occipital transtentorial approach: the occipital bi-transtentorial/falcine approach, to treat such lesions. We present a patient with a large falcotentorial meningioma, located bilaterally in the posterior incisural space. The occipital bi-transtentorial/falcine approach allowed an excellent surgical exposure and complete tumor removal with an excellent patient outcome.

Objective To prospectively evaluate the results of endoscopic choroid plexus cauterization (ECPC) and ventriculoperitoneal shunts (VPSs) in infants with hydranencephaly or near hydranencephaly. Methods We prospectively collected clinical data from all untreated hydranencephalic and near hydranencephalic children from October 2006 to March 2008. All patients treated were randomly divided into 2 groups, ECPC or VPS, and submitted to either endoscopic choroid plexus cauterization or ventriculoperitoneal shunt placement. Results Seventeen patients were entered into the study. ECPC was completed in 9 patients; the procedure successfully controlled excessive head circumference and signs of increased intracranial pressure in 8 of these patients (88.8%). One endoscopic procedure in a hydranencephalic child failed after 7 months, resulting in VPS placement. Thus, of the 10 patients randomized to ECPC, 8 were treated successfully by ECPC (80%), and 2 went on to have a VPS. There were no complications related to this method of treatment. Seven children were randomized to the VPS group; and of these, 2 patients (28.5%) required shunt revisions during follow-up. There were no complications related to shunt placement. There was no difference in the success rate between patients randomized to ECPC and VPS, but the ECPC was more economical. Conclusion ECPC is an acceptable alternative to VPS for treatment of hydranencephaly and near hydranencephaly. It is a single, definitive, safe, effective, and economical treatment that may avoid the complications of shunting.

Decompressive craniectomy (DC) is a surgical technique used to treat patients with elevated intracranial pressure often found in head injury. Its indication remains a controversial issue in the pediatric population.To report seven cases managed with this technique.Retrospective study of seven patients, aged from 2 to 17 years, treated with unilateral DC due to increased intracranial pressure (ICP) as a consequence of head injury. All patients had ICP monitored post operatively and the DC classified as ultra-early (6h), early (6-12h) or late (24h) according to the time of its application. The minimum follow-up was six months.Patients were evaluated with CT scans and clinical exams, and graded according the Glasgow Outcome Scale (GOS). Three patients deceased (GOS1), one was in vegetative state (GOS2), two recovered but still requiring nursing care (GOS3 and 4), and one had a full recovery (GOS5) at hospital discharge. After six months the GOS2 and a GOS3 patients achieved full recovery (GOS5). Subdural collection (2), hydrocephalus (1) and superficial infection (1) occurred as complication. Two patients had autologous cranioplasty and the other two heterologous cranioplasty.Decompressive craniectomy remains a feasible treatment method to lower the ICP, but is not safe from complications. A multicentric study should be done for appropriate protocol treatment of pediatric patients.

Twenty-two patients harboring tumors or vascular lesions (AVMs and aneurysms) located at the posterior aspect of the parahipocampal gyrus and the pulvinar of thalamus operated by supratentorial-infraoccipital approach were analysed. Total resection was achieved in all five AVM patients as well as in six out of fifteen tumor patients. This approach was performed in five anatomical specimens (ten approaches); It results, along with the surgical results, allow this approach to be considered a good option for lesions of the pulvinar of thalamus and postero-medial temporal lobe which are evident at the transverse fissure.

Objective: The recommended treatment for solitary calvarial eosinophilic granuloma (EG) is surgical resection by curettage, craniectomy or craniotomy. The purpose of this study was to describe the spontaneous resolution of calvarial EG and discuss ‘observation only’ as an option in the management of this condition. Methods: A retrospective review was performed of children with calvarial EG seen at a tertiary care children’s hospital. Of a total of 17 such patients, four were managed without any intervention and formed the basis of this report. Results: In all four patients treated by ‘observation only’, there was a tender calvarial mass which enlarged rapidly over a few days and then resolved slowly over many weeks. The diagnosis of EG was based on the findings of plain radiographs and/or computed tomography. All masses had resolved by 8 weeks, and the underlying cranial defect filled in spontaneously in all cases. There was no recurrence at follow-up, which ranged from 2 months to 7 years. Conclusions: ‘Observation only’ should be considered as a viable option in the management of children with solitary calvarial masses that have the radiographic features of EG. Consideration should be given to delaying surgical intervention to allow time to see if spontaneous resolution occurs.