Edson Bor-Seng-Shu and Manoel Jacobsen Teixeira
The purpose of this prospective study was to evaluate the cumulative incidence, duration, and time course of cerebral vasospasm after traumatic brain injury (TBI) in a cohort of 299 patients.
Transcranial Doppler (TCD) ultrasonography studies of blood flow velocity in the middle cerebral and basilar arteries (VMCA and VBA, respectively) were performed at regular intervals during the first 2 weeks posttrauma in association with 133Xe cerebral blood flow (CBF) measurements. According to current definitions of vasospasm, five different criteria were used to classify the patients: A (VMCA > 120 cm/second); B (VMCA > 120 cm/second and a Lindegaard ratio [LR] > 3); C (spasm index [SI] in the anterior circulation > 3.4); D (VBA > 90 cm/second); and E (SI in the posterior circulation > 2.5). Criteria C and E were considered to represent hemodynamically significant vasospasm. Mixed-effects spline models were used to analyze the data of multiple measurements with an inconsistent sampling rate.
Overall 45.2% of the patients demonstrated at least one criterion for vasospasm. The patients in whom vasospasm developed were significantly younger and had lower Glasgow Coma Scale scores on admission. The normalized cumulative incidences were 36.9 and 36.2% for patients with Criteria A and B, respectively. Hemodynamically significant vasospasm in the anterior circulation (Criterion C) was found in 44.6% of the patients, whereas vasospasm in the BA—Criterion D or E—was found in only 19 and 22.5% of the patients, respectively. The most common day of onset for Criteria A, B, D, and E was postinjury Day 2. The highest risk of developing hemodynamically significant vasospasm in the anterior circulation was found on Day 3. The daily prevalence of vasospasm in patients in the intensive care unit was 30% from postinjury Day 2 to Day 13. Vasospasm resolved after a duration of 5 days in 50% of the patients with Criterion A or B and after a period of 3.5 days in 50% of those patients with Criterion D or E. Hemodynamically significant vasospasm in the anterior circulation resolved after 2.5 days in 50% of the patients. The time course of that vasospasm was primarily determined by a decrease in CBF.
The incidence of vasospasm after TBI is similar to that following aneurysmal subarachnoid hemorrhage. Because vasospasm is a significant event in a high proportion of patients after severe head injury, close TCD and CBF monitoring is recommended for the treatment of such patients.
Nícollas Nunes Rabelo, Bruno Braga Sisnando da Costa, Manoel Jacobsen Teixeira, and Eberval Gadelha Figueiredo
Erich Talamoni Fonoff, William Omar Contreras Lopez, Ywzhe Sifuentes Almeida de Oliveira, and Manoel Jacobsen Teixeira
The aim of this study was to show that microendoscopic guidance using a double-channel technique could be safely applied during percutaneous cordotomy and provides clear real-time visualization of the spinal cord and surrounding structures during the entire procedure.
Twenty-four adult patients with intractable cancer pain were treated by microendoscopic-guided percutaneous radiofrequency (RF) cordotomy using the double-channel technique under local anesthesia. A percutaneous lateral puncture was performed initially under fluoroscopy guidance to localize the target. When the subarachnoid space was reached by the guiding cannula, the endoscope was inserted for visualization of the spinal cord and surrounding structures. After target visualization, a second needle was inserted to guide the RF electrode. Cordotomy was performed by a standard RF method.
The microendoscopic double-channel approach provided real-time visualization of the target in 91% of the cases. The other 9% of procedures were performed by the single-channel technique. Significant analgesia was achieved in over 90% of the cases. Two patients had transient ataxia that lasted for a few weeks until total recovery.
The use of percutaneous microendoscopic cordotomy with the double-channel technique is useful for specific manipulations of the spinal cord. It provides real-time visualization of the RF probe, thereby adding a degree of safety to the procedure.
Sergio Brasil, Marcelo de-Lima-Oliveira, Edson Bor-Seng-Shu, and Manoel Jacobsen Teixeira
Manoel Jacobsen Teixeira, Fabrício Freitas de Almeida, Ywzhe Sifuentes Almeida de Oliveira, and Erich Talamoni Fonoff
Over the past few decades, various authors have performed open or stereotactic trigeminal nucleotractotomy for the treatment of neuropathic facial pain resistant to medical treatment. Stereotactic procedures can be performed percutaneously under local anesthesia, allowing intraoperative neurological examination as a method for target refinement. However, blind percutaneous procedures in the region of the atlantooccipital transition carry a considerably high risk of vascular injuries that may bring prohibitive neurological deficit or even death. To avoid such complications, the authors present the first clinical use of microendoscopy to assist percutaneous radiofrequency trigeminal nucleotractotomy. The aim of this article is to demonstrate intradural microendoscopic visualization of the medulla oblongata through an atlantooccipital percutaneous approach.
The authors present a case of severe postherpetic facial neuralgia in a patient who underwent the procedure and had satisfactory results. Stereotactic computational image planning for targeting the spinal trigeminal tract and nucleus in the posterolateral medulla was performed, allowing for an accurate percutaneous approach. Immediately before radiofrequency electrode insertion, a fine endoscope was introduced to visualize the structures in the cisterna magna.
Microendoscopic visualization offered clear identification of the pial surface of the medulla oblongata and its blood vessels, the arachnoid membrane, cranial nerve rootlets and their entry zone, and larger vessels such as the vertebral arteries and the branches of the posterior inferior cerebellar artery.
The initial application of this technique suggests that percutaneous microendoscopy may be useful for particular manipulation of the medulla oblongata, increasing the safety of the procedure and likely improving its effectiveness.
Giselle Coelho, Eberval Gadelha Figueiredo, Nícollas Nunes Rabelo, Manoel Jacobsen Teixeira, and Nelci Zanon
Craniosynostosis is a premature cranial suture junction and requires a craniectomy to decrease cranial compression and remodel the affected areas of the skull. However, mastering these neurosurgical procedures requires many years of supervised training. The use of surgical simulation can reduce the risk of intraoperative error. The authors propose a new instrument for neurosurgical education, which mixes reality with virtual and realistic simulation for repair of craniosynostosis (scaphocephaly type).
This study tested reality simulators with a synthetic thermo-retractile/thermosensitive rubber joined with different polymers. To validate the model, 18 experienced surgeons participated in this study using 3D videos developed using 3DS Max software. Renier’s “H” technique for craniosynostosis correction was applied during the simulation. All participants completed questionnaires to evaluate the simulator.
An expert surgical team approved the craniosynostosis reality and virtual simulators. More than 94% of participants found the simulator relevant, considering aspects such as weight, surgical positioning, dissection by planes, and cranial reconstruction. The consistency and material resistance were also approved on average by more than 60% of the surgeons.
The virtual simulator demands a high degree of effectiveness with 3D perception in anatomy and operative strategies in neurosurgical training. Physical and virtual simulation with mixed reality required psychomotor and cognitive abilities otherwise acquired only during practical surgical training with supervision.
Weston Northam, Kristi Hildebrand, Scott Elton, and Carolyn Quinsey
Jose Weber Vieira de Faria, Manoel Jacobsen Teixeira, Leonardo de Moura Sousa Júnior, Jose Pinhata Otoch, and Eberval Gadelha Figueiredo
The authors sought to construct, implement, and evaluate an interactive and stereoscopic resource for teaching neuroanatomy, accessible from personal computers.
Forty fresh brains (80 hemispheres) were dissected. Images of areas of interest were captured using a manual turntable and processed and stored in a 5337-image database. Pedagogic evaluation was performed in 84 graduate medical students, divided into 3 groups: 1 (conventional method), 2 (interactive nonstereoscopic), and 3 (interactive and stereoscopic). The method was evaluated through a written theory test and a lab practicum.
Groups 2 and 3 showed the highest mean scores in pedagogic evaluations and differed significantly from Group 1 (p < 0.05). Group 2 did not differ statistically from Group 3 (p > 0.05). Size effects, measured as differences in scores before and after lectures, indicate the effectiveness of the method. ANOVA results showed significant difference (p < 0.05) between groups, and the Tukey test showed statistical differences between Group 1 and the other 2 groups (p < 0.05). No statistical differences between Groups 2 and 3 were found in the practicum. However, there were significant differences when Groups 2 and 3 were compared with Group 1 (p < 0.05).
The authors conclude that this method promoted further improvement in knowledge for students and fostered significantly higher learning when compared with traditional teaching resources.
Davi J. Fontoura Solla, Manoel Jacobsen Teixeira, and Wellingson Silva Paiva
Nícollas Nunes Rabelo, Renan Salomão Rodrigues, Arthur Araújo Massoud Salame, Paulo Henrique Braz-Silva, Manoel Jacobsen Teixeira, and Eberval Gadelha Figueiredo