Microsurgical Management Research Articles

Manejo microquirúrgico de fístula arteriovenosa dural tentorial entre arteria de Bernasconi-Cassinari y vena de Galeno guiada por angiografía intraoperatoria: reporte de caso y revisión de la literatura

Las fístulas arteriovenosas durales (FAVDs) son conexiones vasculares anómalas entre arterias durales y senos venosos ovenas corticales encefálicas. Estos cortocircuitos pueden cursar con isquemia o hemorragia intracraneanas que derivan delaumento en el drenaje de los senos venosos o de la hipertensión venosa cortical, implícitos en su fisiopatología. La técnica‘Gold standard’ para su diagnóstico es la angiografía cerebral por sustracción digital, sin embargo, existen diferentes técnicas de imagen que aportan información importante para su caracterización y clasificación. Dentro de estos sistemas de clasificación tenemos el sistema Borden-Shucart y la escala de Cognard, que son los más utilizados. Las estrategias terapéuticas para su manejo incluyen métodos endovasculares y/o quirúrgicos. En términos generales el manejo endovascular ha reemplazado al manejo quirúrgico en los últimos años, dado que se asocia a menor tasa de morbimortalidad (mortalidad < 9%) y menor tiempo de estancia hospitalaria. Las fístulas arteriovenosas durales tentoriales (FAVDTs) corresponden al 4 a 8% del total de FAVDs y son el subtipo con mayor riesgo de sangrado, que se presenta en 38 a 74% de los pacientes. En el presente artículo se describe el caso de un paciente adulto con una FAVDT entre la arteria de Bernasconi-Cassinari y la vena de Galeno asociada a hemorragia mesencefálica. El paciente fue llevado a manejo microquirúrgico guiado por angiografía intraoperatoria, obteniendo una oclusión completa del defecto fistuloso sin complicaciones y con adecuada evolución postoperatoria.

Evaluation of functional outcome of microsurgical management of lumbar canal stenosis

Evaluation of functional outcome of microsurgical management of lumbar canal stenosis - IJN- Print ISSN No: - 2581-8236 Online ISSN No:- 2581-916X Article DOI No:- 10.18231/j.ijn.2019.040, IP Indian Journal of Neurosciences-IP Indian J Neurosci

Microsurgical Management of Midbrain Cavernous Malformations: Predictors of Outcome and Lesion Classification in 72 Patients.

Due to the complex segmental organization of the brainstem, it is preferable to study midbrain cavernous malformations (MCMs) separately from pontine and medullary lesions. To evaluate clinical results after microsurgical removal of MCMs, assess predictors for outcome and introduce a topographical classification of MCMs. A retrospective study was conducted on consecutive patients who underwent MCM resection. Clinical parameters before and after surgery, morphological CM features, surgical approaches and outcomes were analyzed. MCMs were classified according to their exact location within the midbrain and their axial and sagittal extension. The authors reviewed 72 patients (35 male). Lesions varied in size between 4 and 55 mm. The vast majority of patients benefited from surgery. The mean modified Rankin Scale (mRS) decreased significantly from 1.6 at admission to 1.3 at discharge and to 0.7 at follow-up (6-247 mo postoperatively). Five patients (6.9%) suffered from delayed hypertrophic olivary degeneration as visualized on magnetic resonance imaging. One male suffered from early postoperative re-bleeding that required surgical hematoma evacuation. There were no severe long tract impairment or other disabling complications, no delayed re-bleedings, and no surgical mortality. We present a new topographic classification of MCMs that may be useful for predicting the occurrence of postoperative eye movement disorders. Other predictors of persistent oculomotor disturbances are time interval between onset of symptoms and surgery, and patient's age over 40yr. Early surgery is recommendable in patients with oculomotor disturbances. MCM size over 18 mm, patient age over 40yr, and poor mRS at admission are important predictors for the long-term outcome.

Microsurgical Management of Vestibular Schwannomas with Brainstem Compression: Surgical Challenges and Outcome

Background: Vestibular schwannomas exerting brainstem compression with or without hydrocephalus are challenging for neurosurgeons regarding the plan of surgery, operative risk and postoperative sequale. Purpose: To report our experience with the surgical challenges and outcomes for Hannover type T4a & T4b vestibular schwannomas. Methods: Retrospective case study conducted at neurosurgery department, Mansoura University between October 2016 and May 2019 of 16 patients with vestibular schwannoma compressing the brainstem. We reviewed their clinical, radiological, surgical data, incidence of complications and outcome. Results: We had 16 patients: 10 of Hanover grade T4b and 6 of grade T4a. Gross total resection was achieved in 2 cases while subtotal resection was achieved in 5 cases and in the remaining 9 cases; only partial resection was feasible. We had 4 cases of mortality. Among new onset morbidity after surgery, 3 cases had post-operative bulbar manifestation and 4 cases had brainstem dysfunction. Conclusion: Vestibular schwannomas compressing the brain stem are challenging in their clinical presentation, surgery and post-operative outcome. The outcome of patients treated with hydrocephalus prior to vestibular schwannoma surgery is better than those who did initial VS surgery. Patients presented with significant brainstem, bulbar manifestation had worse outcome and needed longer ICU stay and longer time for recovery.

Microsurgical Management of Intracranial Aneurysms in Côte d’Ivoire: A Series of 128 Cases

Introduction: The management of intracranial aneurysms in sub-Saharan Africa is essentially surgical. In this retrospective study, the authors report their experience in surgical management of intracranial aneurysm in Côte d’Ivoire. Methods: We carried out a retrospective study on patients operated for a ruptured or unruptured intracranial aneurysm between January 1st, 2012 and December 31st, 2018. Data on epidemiological characteristics of patients and aneurysms, treatments and patient outcomes were analyzed. Results: One hundred twenty eight aneurysms were operated. Sixty-six percent of the patients were female. According to the World Federation of Neurosurgical Societies (WFNS) scale, 58, 5% of patients were in grade I. Fisher scale showed 29% of Fisher 2 and 49% of Fisher 4. The aneurysms were mainly located on the internal carotid artery in 38% and anterior complex in 36%. The average size of aneurysms was 6.5 mm. In 81.4% the size of the aneurysms was less than 10 mm. Most aneurysms (90%) were treated at late stage. According to the modified Rankin Scale, 92 patients (83%) had good outcome, 7 patients (6%) had poor outcome, and the mortality rate was 11%. Conclusions: This study shows encouraging results if we refer to the overall postoperative results. However, there is a sub-diagnosis and low treatment rate of ruptured intracranial aneurysms. The improvement of intracranial aneurysms management requires improving the standard of health in the country.

Microsurgical Strategies for the Treatment of Compression Neuropathies Secondary to Vertebrobasilar Dolichoectasia: From Simple Decompression to Sling Transposition

Vertebrobasilar artery dolichoectasia may result in neural element compression anywhere along its course within the cervical region, the craniocervical junction or in the posterior fossa. The clinical syndromes most often observed include cranial neuropathy, bulbar dysfunction, myelopathy and cervical radiculopathy. When indicated, the operative techniques utilized to address vertebrobasilar artery dolichoectasia must be individually tailored, can be technically challenging, and have been rarely expounded. To share selected cases that demonstrate the variety of pathological states caused by vertebrobasilar artery dolichoectasia as well as our experience in managing this condition. Here we review examples of pathological impingement of neural elements compressed by ectasia within the vertebrobasilar arterial system throughout its anatomic course. The surgical techniques we have employed to alleviate the compression, including simple decompression as well as sling-assisted arterial transposition, are described. The evolution and refinement of our transposition technique are detailed. A wide range of pathological conditions may result from compression of neural structures throughout the course of the vertebrobasilar system. Compression of cervical nerve roots, the spinal cord, brainstem, and cranial nerves can be seen. Microsurgical management may be indicated in selected cases with gratifying results. Pathological compression of neural structures throughout the course of the vertebrobasilar system should be recognized. When indicated, microsurgical decompression must be tailored to the individual symptomology and the unique anatomic relationship in each case with the potential to prevent neurological worsening and, in many cases, improve functional outcome.

Midline Suboccipital Subtonsillar Approach with C1 Laminectomy for Resection of Foramen Magnum Meningioma: 2-Dimensional Operative Video

We present a case of a medium-sized foramen magnum meningioma that was resected through a midline suboccipital subtonsillar approach with C1 laminectomy in prone (Concorde) position. The patient is a 77-year-old woman with a 6-month history of intermittent vertigo, moderate gait instability, and slight decline of memory.On magnetic resonance imaging (MRI) an extra-axial intradural lesion was discovered that originated from the right epicondylar region just inferior to the jugular tubercle and occupied the anterolateral aspect of the foramen magnum. There was moderate transposition and compression of the medulla at the level of the cerebellar tonsils.On physical examination the patient was ambulatory independently without motor weakness but exhibited some gait instability. The function of the lower cranial nerves was preserved.A gross-total resection was achieved, histopathology confirmed a WHO grade-I meningothelial meningioma with a low-proliferation index. The patient was discharged home 5 days after surgery, her gait instability improved significantly immediately after surgery and had resolved completely after 2 weeks of inpatient rehabilitation. There was no other neurological deficit. At 3-month follow-up MRI, there was no indication of meningioma residual or recurrence.In summary, the midline suboccipital subtonsillar approach is a powerful tool with limited morbidity in the armamentarium for the microsurgical management of a variety of pathologies residing in the posterior cranial fossa and the craniocervical junction. Oftentimes the space created by the pathology opens up corridors that can be exploited for microsurgical access to avoid more extensive surgical approaches. The link to the video can be found at: https://youtu.be/0uUxs13ze7w .

Microsurgical Management of Intracranial Aneurysms After Flow Diversion Failure

Microsurgical Management of Intracranial Aneurysms After Flow Diversion Failure

Acceso minipterional interfascial simple y combinado, con peeling de fosa media y clinoidectomia anterior extradural. Serie clínica

Introducción: En las últimas dos décadas al acceso pterional clásico descrito por Yasargil se le han realizado modificacionesimportantes en búsqueda de acceder a la base del cráneo, tales como el acceso transcigomático y orbitocigomático; más recientemente, accesos mínimamente invasivos, abordajes keyhole. Es así como se ha descrito el acceso minipterionalcon disección interfascial, el que ha sido combinado con técnicas de la base del cráneo, clinoidectomía anterior extradural,peeling de fosa media y petrosectomía anterior de Kawase, por el equipo de Neurocirugía Vascular y de la base del Cráneodel Instituto de Neurocirugía (INCA), a cargo del Dr. Jorge Mura, logrando resolver patologías complejas por un acceso keyhole. Este trabajo presenta una serie clínica, multicéntrica, realizada por un mismo neurocirujano, y que tiene como objetivo demostrar que el acceso minipterional simple y combinado es reproducible en otros centros, con buenos resultados clínicos. Materiales y Métodos: El autor presenta una serie clínica, de 56 pacientes, tratados en el hospital San Pablo de Coquimbo y Clínica Elqui de La Serena, entre abril de 2017 y agosto de 2018, con un seguimiento prospectivo de los resultados clínicos, los cuales fueron evaluados con la escala de Rankin modificado. Resultados: En un total de 56 casos, predominó el sexo femenino (71%), la edad media fue de 53 años y la patología aneurismática fue lo más frecuente con 45 casos, de estos el 60% fueron aneurismas rotos; el 7% correspondieron a tumores de la base del cráneo y el 12,5% a hidrocefalias no comunicantes resueltas por la apertura de la lámina terminalis. En 9 casos se combinó el acceso minipterional con clinoidectomía anterior extradural y en 3 casos se hizo un peeling de fosa media. El mayor tiempo quirúrgico estuvo asociado al acceso minipterional combinado, ya sea por patología tumoral o aneurismas paraclinoideos. Se obtuvo un resultado neurológico favorable (ERm < 3) en el 87,5% de los pacientes. Conclusión y Discusión: actualmente la evidencia ha dejado de manifiesto que el acceso minipterional tiene ventajas sobre otros accesos keyhole, principalmente por la posibilidad de poder combinarlo con técnicas de base del cráneo, pudiendo resolver patologías que antes no era posible tratar por accesos mínimamente invasivos. El acceso pterional clásico, sin embargo, sigue teniendo indicación en casos seleccionados. Por otra parte, esta serie clínica confirma que el acceso minipterional simple y combinado, es reproducible y que, utilizándolo con un adecuado manejo microquirúrgico, logra buenos resultados en patologías complejas.

Microsurgical Management of Intracranial Aneurysms After Failed Flow Diversion

Flow diversion has become increasingly popular for treatment of cerebral aneurysms in the past few years. In an increasing number of patients with aneurysms, flow diversion (FD) has failed, with a paucity of reported data regarding salvage treatment for these challenging cases. We present a multicenter series of 13 aneurysms for which FD failed and that were subsequently treated with open surgery. We also present a review of the reported data regarding operative management of aneurysms after unsuccessful FD. Twelve patients with 13 aneurysms were included in the present study. All 12 patients had undergone surgery after FD because of persistent aneurysm filling, mass effect, or aneurysm rupture. The patients underwent aneurysm clipping and parent vessel reconstruction, decompression of the aneurysm mass, occlusion of proximal flow to the aneurysm, or aneurysm trapping with or without extracranial-intracranial artery bypass. Aneurysms for which FD fails present a variety of unique and challenging management situations that will likely be encountered with increased frequency, given the popularity of FD. Microsurgical salvage options require individualized care tailored to the underlying pathological features, patient characteristics, and surgical expertise.

Vein of Galen arteriovenous malformation: Unedited microneurosurgery

Background:Vein of Galen arteriovenous malformations (VGAVMs) are vascular malformations of the pineal region between a persistent embryological median prosencephalic vein of Markowski and the arterial choroidal system by a direct (mural type) or indirect (choroidal type) communication. Angiographic evaluation of VGAVMs usually describes a limbic arch between the anterior and posterior cerebral arteries throughout a pericallosal artery, and the classic “ε” shape configuration of the thalamostriate veins drainage into a subtemporal or a lateral mesencephalic vein due to the underdevelopment of the straight sinus, sigmoid sinus, and jugular bulbs. Moreover, falcine dural channels join the pouch of the malformation with the posterior third of the superior sagittal sinus and less frequently with the cavernous sinus, inferior petrosal sinus, and facial veins. At present, endovascular therapy is the standard management for these lesions. However, under failure of endovascular procedures such in this case, microsurgical management of VGAVMs under an experienced neurosurgical team might be paramount.Case Description:The patient with a choroidal type VGAVM and multiple failed endovascular procedures underwent sitting praying position and midline supracerebellar infratentorial approach. Strong retraction with stitches and proper hemostasis of a highly vascular dura was achieved after transverse sinus-based opening. Accurate microsurgical dissection between the superior cerebellar surface and the tentorium allowed a supracerebellar approach over the vermis and along the midline recognizing the venous pouch of the VGAVM instead of the absent straight sinus. Water dissection allowed us to differentiate the cleavage plane between the VGAVM and surrounding structures maintaining an impeccable surgical field as well. Under high microscopic magnification, arterial feeders of the malformation coming from the posterior cerebral artery were recognized. Intraoperative angiography and reevaluation of the preoperative imaging helped us to confirm a safety approach before coagulation and cut those vascular feeders. Throughout an open-close and short bursts bipolar coagulation techniques preventing attachment of conventional bipolar tips within the vascular structure and without permanent use of water irrigation, the vessels were carefully dissected, coagulated, and sectioned. Along with our experience, we believe that this standard coagulation technique applied in all vascular malformation surgeries is safe and effective. A remaining small plexiform malformation associated with the vein of Galen malformation was coagulated and isolated. A new intraoperative angiography determined complete microsurgical occlusion of the VGAVM. Careful homeostasis based on electrocoagulation and surgical was achieved. Finally, we performed a microsurgical wound closure as a conventional technique in Helsinki neurosurgery.Conclusion:This unedited video offers all detailed aspects that a neurosurgeon as the senior author JH considers essential when performing an efficient and safe surgery for a VGAVM.Videolink:http://surgicalneurologyint.com/videogallery/vein-of-galen-avm.

The microsurgical management of benign pineal cysts: Helsinki experience in 60 cases.

Background:Microsurgical resection represents a well-accepted management option for symptomatic benign pineal cysts. Symptoms such as a headache, hydrocephalus, and visual deficiency are typically associated with pineal cysts. However, more recent studies reported over the past years have characterized additional symptoms as a part of the clinical manifestation of this disease and represent additional indications for intervention.Methods:We present a retrospective review of patients with histologically confirmed benign pineal cysts that were operated on in our department between 1997 and 2015. A demographic analysis, evaluation of preoperative status, surgical treatment, as well as immediate and long-term clinical and radiological outcomes were conducted.Results:A total of 60 patients with benign pineal cysts underwent surgery between 1997 and 2015. Gross total resection was achieved in 58 cases. All patients except one improved in their clinical status or had made a full recovery at the time of the last follow-up. The key steps for surgical resection of pineal cysts are reported, based on an analysis of representative surgical videos.Conclusions:We describe in this paper one of the largest series of microsurgically treated pineal cysts. In our opinion, judicious microsurgery remains the most suitable technique to effectively deal with this disease.

Microsurgical Management of a Spinal Dural Arteriovenous Fistula With Shared Blood Supply to the Artery of Adamkiewicz: 3-Dimensional Operative Video.

The presented case is of a 65-yr-old gentleman referred for thoracic myelopathy. He developed bilateral, nondermatomal foot dysesthesia 14 mo prior to presentation, which progressed to numbness below the L3 level. He reported progressive gait instability, bilateral lower extremity weakness, and required a cane for ambulation. He subsequently developed urinary incontinence, while bowel function was spared. The neurological examination upon presentation revealed lower extremity strength was reduced to 4/5 in all major muscle groups bilaterally, while sensation and proprioception were reduced below the L3 level. Patellar and Achilles reflexes were not elicited and clonus was absent. Gait was unsteady and slow. The patient was not able to perform heel, toe and tandem gait. MRI revealed abnormal T2 hyper-intense signal and spinal cord expansion from T6 through the conus medullaris. Angiography revealed a dural arteriovenous fistula (dAVF) originating from the left T9 radicomedullary pedicle, which also supplied the Artery of Adamkiewicz (AoA). The patient underwent T8-10 laminectomies. Prior to disconnection of the fistula, an aneurysm clip was applied to the fistulous point and an indocyanine green video angiogram was completed to show that the fistula no longer opacified, but that the AoA remained patent, which was later confirmed with angiography. As of discharge, the patient's motor exam had improved substantially, though his sensory deficits persisted. This case demonstrates that surgical disconnection is requisite in the treatment of spinal dAVF that have a shared blood supply with the AoA, as embolization risks spinal cord infarction. The patient consented to presentation of this case in a de-identified fashion.

Simple assessment of the localization of posterior communicating artery aneurysms to the anterior petroclinoid ligament

The microsurgical management of posterior communicating artery (PCoA) aneurysms can be modified depending on their localization, with respect to the tentorial edge consisting of the anterior petroclinoid ligament (APCL). However, the imaging of APCL has been impractical to date. In this study, we evaluated a simple method for assessing the relationship between PCoA aneurysms and APCL, using three-dimensional computed tomographic angiography (3D-CTA). We retrospectively reviewed all surgically treated cases of PCoA aneurysms via the pterional approach in our institute from May 2013 to August 2018. To predict the localization of the aneurysms, three anatomical lines were drawn on non-subtracted volumetric 3D-CTA as follows: 1. the apex of the anterior clinoid process to the posterior border of the trigeminal depression of the petrosal bone (AACP-PBTD); 2. AACP to the superior edge of the arcuate eminence (AACP-SEAE); 3. the base of the ACP to the superior edge of the arcuate eminence (BACP-SEAE). The relative location of each line to the PCoA aneurysms was compared with actual intraoperative findings. Fifty-six aneurysms were included. The sensitivity, specificity, and positive and negative predictive values of the superior localization of the aneurysm of the AACP-TDPB line were 93.8%, 40.0%, 38.5%, and 94.1%, respectively. Those of the AACP-SEAE line were 93.8%, 42.5%, 39.5, and 94.4%, respectively. In contrast, those of the BACP-SEAE line were 93.8%, 97.5%, 93.8%, and 97.5%, respectively. The BACP-SEAE line is a simple and practical landmark in predicting APCL.

Microsurgical Management of Ruptured Blood Blister Aneurysms of the Internal Carotid Artery without Bypass: A Retrospective Single-Center Study of 36 Patients over 20 Years

Microsurgical management of blood blister aneurysms of the internal carotid artery is challenging because of the special characteristics of these aneurysms. We reviewed our diverse surgical methods with long-term clinical and radiologic follow-up. We retrospectively reviewed all patients with blood blister aneurysms presenting with subarachnoid hemorrhage that were treated with microsurgical obliteration between 1993 and 2017. Baseline characteristics of patients and aneurysms, surgical methods, and clinical and radiologic outcomes were analyzed. This study included 36 patients. The patients were treated using microsurgery with direct clipping (2 patients; 5.6%), cotton-assisted clipping (24 patients; 66.7%), wrapping-clipping (5 patients; 13.9%), or wrapping-clipping with suturing (5 patients; 13.9%). Complete occlusion of aneurysm was achieved in 34 of 36 patients (94.4%). Severe vasospasm developed in 18 of 36 patients (50%). Ischemic events occurred in 8 patients (22.2%), 2 of whom remained with severe disability. Regrowth or recurrence occurred in 1 patient (0.28%), which required additional stent-assisted coil embolization. Mean modified Rankin Scale score was 2.0 (median, 1.0; range, 0-4) at discharge and 1.3 (median, 1.0; range, 0-4) at the last follow-up. Direct clipping is ideal if possible; however, direct clipping is challenging in most blood blister aneurysms. Assisted clipping with cotton is mainly used and could be an effective technique for reinforcement of the friable wall, with good clinical outcomes in our series. Moreover, suturing followed by wrapping-clipping is also useful for managing intraoperative rupture.

The future of open vascular neurosurgery: perspectives on cavernous malformations, AVMs, and bypasses for complex aneurysms.

Despite the erosion of microsurgical case volume because of advances in endovascular and radiosurgical therapies, indications remain for open resection of pathology and highly technical vascular repairs. Treatment risk, efficacy, and durability make open microsurgery a preferred option for cerebral cavernous malformations, arteriovenous malformations (AVMs), and many aneurysms. In this paper, a 21-year experience with 7348 cases was reviewed to identify trends in microsurgical management. Brainstem cavernous malformations (227 cases), once considered inoperable and managed conservatively, are now resected in increasing numbers through elegant skull base approaches and newly defined safe entry zones, demonstrating that microsurgical techniques can be applied in ways that generate entirely new areas of practice. Despite excellent results with microsurgery for low-grade AVMs, brain AVM management (836 cases) is being challenged by endovascular embolization and radiosurgery, as well as by randomized trials that show superior results with medical management. Reviews of ARUBA-eligible AVM patients treated at high-volume centers have demonstrated that open microsurgery with AVM resection is still better than many new techniques and less invasive approaches that are occlusive or obliterative. Although the volume of open aneurysm surgery is declining (4479 cases), complex aneurysms still require open microsurgery, often with bypass techniques. Intracranial arterial reconstructions with reimplantations, reanastomoses, in situ bypasses, and intracranial interpositional bypasses (third-generation bypasses) augment conventional extracranial-intracranial techniques (first- and second-generation bypasses) and generate innovative bypasses in deep locations, such as for anterior inferior cerebellar artery aneurysms. When conventional combinations of anastomoses and suturing techniques are reshuffled, a fourth generation of bypasses results, with eight new types of bypasses. Type 4A bypasses use in situ suturing techniques within the conventional anastomosis, whereas type 4B bypasses maintain the basic construct of reimplantations or reanastomoses but use an unconventional anastomosis. Bypass surgery (605 cases) demonstrates that open microsurgery will continue to evolve. The best neurosurgeons will be needed to tackle the complex lesions that cannot be managed with other modalities. Becoming an open vascular neurosurgeon will be intensely competitive. The microvascular practice of the future will require subspecialization, collaborative team effort, an academic medical center, regional prominence, and a large catchment population, as well as a health system that funnels patients from hospital networks outside the region. Dexterity and meticulous application of microsurgical technique will remain the fundamental skills of the open vascular neurosurgeon.

Retrosigmoid Approach: A Simple and Safe Way to Resect Intrinsic Pontomedullary Lesions.

Objectives The main objective of this article is to describe a simple and safe protocol for the microsurgical management of ventrally located intrinsic pontomedullary lesions based on the retrosigmoid approach, cortectomy performed utilizing safe entry zones of the pons and medulla, and a delicate microsurgical resection. The intraoperative protocol includes redundant procedures that provide security in decision-making during surgery. Design A prospective series of 11 cases is presented. All patients were studied following the same clinical and imaging workup. A regular retrosigmoid craniotomy surgical approach was utilized. The peritrigeminal area in the pons and the olivary area in the medulla were considered as the safe entry zones. Neuronavigation of the white fiber tracts and electrophysiological monitoring were used as intraoperative aids to locate the lesions, the safe entry zones, and the placement of the cortectomy. Results Six lesions were pontine, two medullary, and the remaining six pontomedullary. Eight lesions were cavernomas, while the remaining three tumors. Overall, we obtained a postoperative functional improvement in the affected cranial nerves in 90.1% of the patients and a total or partial recovery of long ascending or descending pathway symptoms in 72.3% of the patients. All the patients were satisfied with the procedure and the results. Conclusions Radical resection of ventral intrinsic pontomedullary lesions displays a high degree of intraoperative reliability, and a good clinical result is possible using simple surgical procedures. The anatomical references are the first element in the decision-making process during surgery.

Outcomes with microsurgery of common peroneal nerve lesions

The purpose of this retrospective study is to present our results with peroneal nerve lesions, to examine the relative significance of various factors, to assess their effect on outcome, and to establish guidelines of treatment for the microsurgical management of these difficult lesions. Over a 33-year period, a total of 62 patients were treated at McGill University and the Microsurgical Research Center, Eastern Virginia Medical School. The clinical records of all patients treated for peroneal nerve lesions were reviewed for retrospective analysis. Of 62 patients, 35 had microneurolysis and nerve decompression of the common peroneal nerve (CPn) as the only surgical procedure while 27 required reconstruction with nerve grafting. Postoperatively muscle power was graded from M + 4 to M - 5 in 27 patients, from M - 4 to M4 in 26 patients, from M - 3 to M + 3 in 8 patients, and from M - 2 to M + 2 in 1 patient. The behavioral video data showed a mean preoperative ankle dorsiflexion of 6.79°±5.6 and postoperative ankle dorsiflexion of 37.9°±9.3. Overall, excellent functional results were achieved in 27 of 62 patients (43%) with peroneal palsy who underwent microsurgical reconstruction, and good results were observed in 25 patients (40%). Despite previous widespread pessimism, the surgical repair of CPn lesion is worthwhile, yielding good to excellent results in the majority of patients, after a careful preoperative consultation, establishment of a sound strategy of reconstruction and using aggressive and atraumatic microsurgery.

Microsurgical Management of Fourth Ventricle Astrocytoma via Median Suboccipital Keyhole Approach: Review of 12 Cases

To investigate the clinical effect and surgical techniques of fourth ventricle astrocytoma resection through the median suboccipital keyhole approach. Twelve patients received tumor resection through the median suboccipital keyhole approach in our department. A 4-cm median suboccipital excision starting 1 cm under the foramen magnum region and directed vertically upward was applied. The fourth ventricle was exposed through a cerebellomedullary fissure approach within a bone hole ≈2.5 cm in diameter. All clinical data (including preoperative/postoperative symptoms, magnetic resonance imaging scan, intraoperative findings, tumor resection rate, and surgical complications) were collected and analyzed. In our treatment group, the mean maximum tumor diameter was 3.48 ± 1.3 cm and the mean tumor volume was 34.79 ± 20.70 cm3. The complete resection rate was 92%. The average operative blood loss was 127.0 ± 24.6 mL; the mean craniotomy time was 26.4 ± 6.0 minutes; the mean tumor resection time was 190.3 ± 31.2 minutes; the mean cranial closure time was 42.3 ± 6.1 minutes; and the average hospitalization time was 13.6 ± 2.4 days. The mean Glasgow Outcome Scale score before discharge was 4.92. If appropriate microneurosurgical techniques are used via the median suboccipital keyhole approach, the fourth ventricle astrocytoma may be accessed and resected safely with shorter surgery time, reduced hemorrhage during operation, low incidence of postoperative complications, good recovery, and shorter hospitalization time.

Microsurgical ligation for incompletely coiled or recurrent intracranial aneurysms: a 17-year single-center experience

BackgroundIn this retrospective single-center study, we presented our experience in the microsurgical management of incompletely coiled or recurrent aneurysms after initial endovascular coiling.MethodsDuring a 17-year period, 48 patients underwent microsurgical clipping of incompletely coiled or recurrent aneurysms after coiling (Gurian group B). The clinical data, surgical technique, and postoperative outcome were recorded and analyzed.ResultsBefore coiling, 42 patients (87.5%) experienced aneurysm rupture. Most of the aneurysms (46/48, 96%) were located in the anterior circulation. After coiling, 6 patients had incompletely coiled aneurysms and 42 patients had recurrent aneurysms, with a mean time of 20.2 months from coiling to recurrence. Coil extrusion occurred in none of the incompletely coiled aneurysms and 71% (30/42) of the recurrent aneurysms. Clipping techniques are direct microsurgical clipping without coil removal in 16 patients, partial coil removal in 14 patients, and total coil removal in 18 patients. Postoperative and follow-up angiography revealed complete occlusion of the aneurysms in all patients. No patient died during postoperative follow-up period (mean, 78.9 months; range, 10–190 months). Good outcomes (GOS of 4 or 5) were achieved in 87.5% (42/48) of the patients at the final follow-up.ConclusionsMicrosurgical clipping is effective for incompletely coiled or recurrent aneurysms after initial coiling. For recurrent aneurysms that have coils in the neck, have no adequate neck for clipping, or cause mass effects on surrounding structures, partial or total removal of coiled mass can facilitate surgical clipping and lead to successful obliteration of the aneurysms.