Category: Surgical technique

Posted on

Image-guided endoscopic surgery for spontaneous supratentorial intracerebral hematoma

J Neurosurg 127:537–542, 2017

Endoscopic removal of intracerebral hematomas is becoming increasingly common, but there is no standard technique. The authors explored the use of a simple image-guided endoscopic method for removal of spontaneous supratentorial hematomas.

METHODS Virtual reality technology based on a hospital picture archiving and communications systems (PACS) was used in 3D hematoma visualization and surgical planning. Augmented reality based on an Android smartphone app, Sina neurosurgical assist, allowed a projection of the hematoma to be seen on the patient’s scalp to facilitate selection of the best trajectory to the center of the hematoma. A obturator and transparent sheath were used to establish a working channel, and an endoscope and a metal suction apparatus were used to remove the hematoma.

RESULTS A total of 25 patients were included in the study, including 18 with putamen hemorrhages and 7 with lobar cerebral hemorrhages. Virtual reality combined with augmented reality helped in achieving the desired position with the obturator and sheath. The median time from the initial surgical incision to completion of closure was 50 minutes (range 40–70 minutes). The actual endoscopic operating time was 30 (range 15–50) minutes. The median blood loss was 80 (range 40–150) ml. No patient experienced postoperative rebleeding. The average hematoma evacuation rate was 97%. The mean (± SD) preoperative Glasgow Coma Scale (GCS) score was 6.7 ± 3.2; 1 week after hematoma evacuation the mean GCS score had improved to 11.9 ± 3.1 (p < 0.01).

CONCLUSIONS Virtual reality using hospital PACS and augmented reality with a smartphone app helped precisely localize hematomas and plan the appropriate endoscopic approach. A transparent sheath helped establish a surgical channel, and an endoscope enabled observation of the hematoma’s location to achieve satisfactory hematoma removal.

Posted on

Tractography guides the approach for resection of thalamopeduncular tumors

Acta Neurochir (2017) 159:1597–1601

Thalamopeduncular tumors arise at the junction of the inferior thalamus and cerebral peduncle, and present with a common clinical syndrome of progressive spastic hemiparesis.

Method Formal preoperative magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) were performed. Postoperative MRI was obtained to evaluate the extent of tumor resection. A prospective analysis of clinical outcomes was then conducted by the senior author.

Conclusions Preoperative tractography is a useful adjunct to surgical planning in tumors that displace motor pathways. Gross total resection of pilocytic astrocytomas usually results in cure, and therefore should be entertained when developing treatment strategies for thalamopeduncular tumors of childhood.

Posted on

The Survival Advantage of “Supratotal” Resection of Glioblastoma Using Selective Cortical Mapping and the Subpial Technique

Neurosurgery 81:275–288, 2017

A substantial body of evidence suggests that cytoreductive surgery is a prerequisite to prolonging survival in patients with glioblastoma (GBM).

OBJECTIVE: To evaluate the safety and impact of “supratotal” resections beyond the zone of enhancement seen on magnetic resonance imaging scans, using a subpial technique.

METHODS: We retrospectively evaluated 86 consecutive patients with primary GBM, managed by the senior author, using a subpial resection technique with or without carmustine (BCNU) wafer implantation. Multivariate Cox proportional hazards regression was used to analyze clinical, radiological, and outcome variables. Overall impacts of extent of resection (EOR) and BCNUwafer placementwere compared using Kaplan-Meier survival analysis.

RESULTS: Mean patient age was 56 years. The median OS for the group was 18.1 months. Median OS for patients undergoing gross total, near-total, and subtotal resection were 54, 16.5, and 13.2 months, respectively. Patients undergoing near-total resection (P = .05) or gross total resection (P<.01) experienced statistically significant longer survival time than patients undergoing subtotal resection as well as patients undergoing≥95% EOR (P<.01) when compared to <95% EOR. The addition of BCNU wafers had no survival advantage.

CONCLUSIONS: The subpial technique extends the resection beyond the contrast enhancement and is associated with an overall survival beyond that seen in similar series where resection of the enhancement portion is performed. The effect of supratotal resection on survival exceeded the effects of age, Karnofsky performance score, and tumor volume. A prospective study would help to quantify the impact of the subpial technique on quality of life and survival as compared to a traditional resection limited to the enhancing tumor.

 

Posted on

Contemporary analysis of the intraoperative and perioperative complications of neurosurgical procedures performed in the sitting position

J Neurosurg 127:182–188, 2017

Historically, performing neurosurgery with the patient in the sitting position offered advantages such as improved visualization and gravity-assisted retraction. However, this position fell out of favor at many centers due to the perceived risk of venous air embolism (VAE) and other position-related complications. Some neurosurgical centers continue to perform sitting-position cases in select patients, often using modern monitoring techniques that may improve procedural safety. Therefore, this paper reports the risks associated with neurosurgical procedures performed in the sitting position in a modern series.

METHODS The authors reviewed the anesthesia records for instances of clinically significant VAE and other complications for all neurosurgical procedures performed in the sitting position between January 1, 2000, and October 8, 2013. In addition, a prospectively maintained morbidity and mortality log of these procedures was reviewed for instances of subdural or intracerebral hemorrhage, tension pneumocephalus, and quadriplegia. Both overall and specific complication rates were calculated in relation to the specific type of procedure.

RESULTS In a series of 1792 procedures, the overall complication rate related to the sitting position was 1.45%, which included clinically significant VAE, tension pneumocephalus, and subdural hemorrhage. The rate of any detected VAE was 4.7%, but the rate of VAE requiring clinical intervention was 1.06%. The risk of clinically significant VAE was highest in patients undergoing suboccipital craniotomy/craniectomy with a rate of 2.7% and an odds ratio (OR) of 2.8 relative to deep brain stimulator cases (95% confidence interval [CI] 1.2–70, p = 0.04). Sitting cervical spine cases had a comparatively lower complication rate of 0.7% and an OR of 0.28 as compared with all cranial procedures (95% CI 0.12–0.67, p < 0.01). Sitting cervical cases were further subdivided into extradural and intradural procedures. The rate of complications in intradural cases was significantly higher (OR 7.3, 95% CI 1.4–39, p = 0.02) than for extradural cases. The risk of VAE in intradural spine procedures did not differ significantly from sitting suboccipital craniotomy/craniectomy cases (OR 0.69, 95% CI 0.09–5.4, p = 0.7). Two cases (0.1%) had to be aborted intraoperatively due to complications. There were no instances of intraoperative deaths, although there was a single death within 30 days of surgery.

CONCLUSIONS In this large, modern series of cases performed in the sitting position, the complication rate was low. Suboccipital craniotomy/craniectomy was associated with the highest risk of complications. When appropriately used with modern anesthesia techniques, the sitting position provides a safe means of surgical access.

Posted on

Preoperative planning of hemangioblastoma using 3D imaging

 

J Neurosurg 127:139–147, 2017

Successful resection of hemangioblastoma depends on preoperative assessment of the precise locations of feeding arteries and draining veins. Simultaneous 3D visualization of feeding arteries, draining veins, and surrounding structures is needed.

The present study evaluated the usefulness of high-resolution 3D multifusion medical imaging (hr-3DMMI) for preoperative planning of hemangioblastoma. The hr-3DMMI combined MRI, MR angiography, thin-slice CT, and 3D rotated angiography. Surface rendering was mainly used for the creation of hr-3DMMI using multiple thresholds to create 3D models, and processing took approximately 3–5 hours. This hr-3DMMI technique was used in 5 patients for preoperative planning and the imaging findings were compared with the operative findings. Hr-3DMMI could simulate the whole 3D tumor as a unique sphere and show the precise penetration points of both feeding arteries and draining veins with the same spatial relationships as the original tumor.

All feeding arteries and draining veins were found intraoperatively at the same position as estimated preoperatively, and were occluded as planned preoperatively. This hr-3DMMI technique could demonstrate the precise locations of feeding arteries and draining veins preoperatively and estimate the appropriate route for resection of the tumor. Hr-3DMMI is expected to be a very useful support tool for surgery of hemangioblastoma.

Posted on

Anterior trans-frontal endoscopic resection of third-ventricle colloid cyst

Acta Neurochir (2017) 159:1049–1052

The endoscopic technique has been recognised as a viable and safe alternative to microsurgery for the treatment of third-ventricle colloid cyst. However, the standard precoronal endoscopic approach does not always provide an adequate visualisation of the attachment of the cyst to the velum interpositum. Using a more anterior approach, it is easier to reach the roof of the cyst and its possible adherences with the tela choroidea.

Method The authors describe step by step the anterior transfrontal endoscopic approach for management of third ventricle colloid cyst.

Conclusions The described approach has shown to be safe, quick and effective for the treatment of third-ventricle colloid cyst.

Posted on

A method for safely resecting anterior butterfly gliomas

J Neurosurg 126:1795–1811, 2017

Gliomas invading the anterior corpus callosum are commonly deemed unresectable due to an unacceptable risk/benefit ratio, including the risk of abulia. In this study, the authors investigated the anatomy of the cingulum and its connectivity within the default mode network (DMN). A technique is described involving awake subcortical mapping with higher attention tasks to preserve the cingulum and reduce the incidence of postoperative abulia for patients with so-called butterfly gliomas.

METHODS The authors reviewed clinical data on all patients undergoing glioma surgery performed by the senior author during a 4-year period at the University of Oklahoma Health Sciences Center. Forty patients were identified who underwent surgery for butterfly gliomas. Each patient was designated as having undergone surgery either with or without the use of awake subcortical mapping and preservation of the cingulum. Data recorded on these patients included the incidence of abulia/akinetic mutism. In the context of the study findings, the authors conducted a detailed anatomical study of the cingulum and its role within the DMN using postmortem fiber tract dissections of 10 cerebral hemispheres and in vivo diffusion tractography of 10 healthy subjects.

RESULTS Forty patients with butterfly gliomas were treated, 25 (62%) with standard surgical methods and 15 (38%) with awake subcortical mapping and preservation of the cingulum. One patient (1/15, 7%) experienced postoperative abulia following surgery with the cingulum-sparing technique. Greater than 90% resection was achieved in 13/15 (87%) of these patients.

CONCLUSIONS This study presents evidence that anterior butterfly gliomas can be safely removed using a novel, attention-task based, awake brain surgery technique that focuses on preserving the anatomical connectivity of the cingulum and relevant aspects of the cingulate gyrus.

 

Posted on

Contralateral supraorbital keyhole approach to medial optic nerve

J Neurosurg 126:940–944, 2017

The authors describe the supraorbital keyhole approach to the contralateral medial optic nerve and tract, both in a series of cadaveric dissections and in 2 patients. They also discuss the indications and contraindications for this procedure.

METHODS In 3 cadaver heads, bilateral supraorbital keyhole minicraniotomies were performed to expose the ipsilateral and contralateral optic nerves. The extent of exposure of the medial optic nerve was assessed. In 2 patients, a contralateral supraorbital keyhole approach was used to remove pathology of the contralateral medial optic nerve and tract.

RESULTS The supraorbital keyhole craniotomy provided better exposure of the contralateral superomedial nerve than it did of the same portion of the ipsilateral nerve. In both patients gross-total resections of the pathology was achieved.

CONCLUSIONS The authors demonstrate the suitability of the contralateral supraorbital keyhole approach for lesions involving the superomedial optic nerve.

 

Posted on

The expanded trans/supraorbital approach for large space-occupying lesions of the anterior fossa

Acta Neurochir (2017) 159:881–887

The supraorbital rim often interferes with the required upward movement of the instruments for resection of large frontal-lobe tumours through a classic supraorbital craniotomy. Here, we present the expanded trans/supraorbital approach to overcome these limitations.

Methods After an eyebrow skin incision, a one-piece bone flap was created incorporating the orbital rim and roof. Basal extension of the craniotomy allowed for a better intracranial visualisation with improved manoeuvrability and angulation of the instruments without using brain retraction.

Conclusions This approach poses a feasible alternative to large frontal craniotomies for frontal-lobe tumours, for which a regular supraorbital craniotomy is insufficient.

Posted on

Is lumbar facet fusion biomechanically equivalent to lumbar posterolateral onlay fusion?

J Neurosurg Spine 26:586–593, 2017

This study was designed with the following research objectives: 1) to determine the efficacy of facet fusion with recombinant human bone morphogenetic protein–2 (rhBMP-2) on an absorbable collagen sponge (ACS) in an ovine lumbar facet fusion model; 2) to radiographically and histologically compare the efficacy of lumbar facet fusion with rhBMP-2/ACS to facet fusion with an iliac crest bone graft (ICBG); and 3) to biomechanically compare lumbar facet fusion with rhBMP-2/ACS to lumbar posterolateral fusion (PLF) with ICBG.

METHODS The efficacies of the 3 treatments to induce fusion were evaluated in an instrumented ovine lumbar fusion model. Eight sheep had 10 cm3/side ICBG placed as an onlay graft for PLF at L2–3. At the adjacent L3–4 level, 0.5 cm3/ side ICBG was placed for facet fusion. Finally, 0.5 cm3/side rhBMP-2/ACS (0.43 mg/ml) was placed for facet fusion at L4–5. CT scans were obtained at 2, 4, and 6 months postoperatively with 2 reviewers conducting an evaluation of the 6-month results for all treated spinal levels. All 8 sheep were killed at 6 months, and all posterolateral instrumentation was removed at this time. The spines were then sectioned through L3–4 to allow for nondestructive unconstrained bio- mechanical testing of the L2–3 and L4–5 segments. All treated spinal levels were analyzed using undecalcified histology with corresponding microradiography. Statistical comparisons were made between the treatment groups.

RESULTS The PLF with ICBG (ICBG PLF group) and the rhBMP-2 facet fusion (rhBMP-2 Facet group) treatment groups demonstrated similar levels of stiffness, with the rhBMP-2 Facet group having on average slightly higher stiffness in all 6 loading directions. All 8 levels in the autograft facet fusion treatment group demonstrated CT radiographic and histological fusion. All 8 levels in the rhBMP-2 Facet group showed bilateral CT radiographic and histological fusion. Six of 16 rhBMP-2/ACS-treated facet defects demonstrated small intraosseous hematomas or seromas. Four of the 8 levels (50%) in the ICBG PLF treatment group demonstrated bilateral histological fusion. Three of 8 levels in the ICBG PLF treatment group showed unilateral fusion. One of the 8 levels in the ICBG PLF treatment group demonstrated bilateral histological nonfusion.

CONCLUSIONS Both rhBMP-2/ACS and autograft demonstrated 100% efficacy when used for facet fusion in the instrumented ovine model. However, the ICBG PLF treatment group only demonstrated a 50% bilateral fusion rate. Biomechanically, the ICBG PLF and rhBMP-2 Facet groups demonstrated similar stiffness in all 6 loading directions, with the rhBMP-2 Facet group having on average slightly higher stiffness in all directions.

Posted on

Transtentorial transcollateral sulcus approach to the ventricular atrium

J Neurosurg 126:1246–1252, 2017

Conventional approaches to the atrium of the lateral ventricle may be associated with complications related to direct cortical injury or brain retraction. The authors describe a novel approach to the atrium through a retrosigmoid transtentorial transcollateral sulcus corridor.

METHODS: Bilateral retrosigmoid craniotomies were performed on 4 formalin-fixed, colored latex–injected human cadaver heads (a total of 8 approaches). Microsurgical dissections were performed under 3× to 24× magnification, and endoscopic visualization was provided by 0° and 30° rigid endoscope lens systems. Image guidance was provided by coupling an electromagnetic tracking system with an open source software platform. Objective measurements on cortical thickness traversed and total depth of exposure were recorded. Additionally, the basal occipitotemporal surfaces of 10 separate cerebral hemisphere specimens were examined to define the surface topography of sulci and gyri, with attention to the appearance and anatomical patterns and variations of the collateral sulcus and the surrounding gyri.

RESULTS: The retrosigmoid approach allowed for clear visualization of the basal occipitotemporal surface. The collateral sulcus was identified and permitted easy endoscopic access to the ventricular atrium. The conical corridor thus obtained provided an average base working area of 3.9 cm2 at an average depth of 4.5 cm. The mean cortical thickness traversed to enter the ventricle was 1.4 cm. The intraventricular anatomy of the ipsilateral ventricle was defined clearly in all 8 exposures in this manner. The anatomy of the basal occipitotemporal surface, observed in a total of 18 hemispheres, showed a consistent pattern, with the collateral sulcus abutted by the parahippocampal gyrus medially, and the fusiform and lingual gyrus laterally. The collateral sulcus was found to be caudally bifurcated in 14 of the 18 specimens.

CONCLUSIONS: The retrosigmoid supracerebellar transtentorial transcollateral sulcus approach is technically feasible. This approach has the potential advantage of providing a short and direct path to the atrium, hence avoiding violation of deep neurovascular structures and preserving eloquent areas. Although this approach appears unconventional, it may provide a minimally invasive option for the surgical management of selected lesions within the atrium of the lateral ventricle.

 

Posted on

The Safety and Feasibility of Image-Guided BrainPath-Mediated Transsulcul Hematoma Evacuation: A Multicenter Study

Neurosurgery 80:515–524, 2017

Subcortical injury resulting from conventional surgical management of intracranial hemorrhage may counteract the potential benefits of hematoma evacuation.

OBJECTIVE: To evaluate the safety and potential benefits of a novel, minimally invasive approach for clot evacuation in a multicenter study.

METHODS: The integrated approach incorporates 5 competencies: (1) image interpretation and trajectory planning, (2) dynamic navigation, (3) atraumatic access system (BrainPath, NICO Corp, Indianapolis, Indiana), (4) extracorporeal optics, and (5) automated atraumatic resection. Twelve neurosurgeons from 11 centers were trained to use this approach through a continuing medical education–accredited course. Demographical, clinical,andradiologicaldataofpatientstreatedover2yearswereanalyzedretrospectively.

RESULTS: Thirty-nine consecutive patients were identified. The median Glasgow Coma Scale (GCS) score at presentation was 10 (range, 5-15). The thalamus/basal ganglion regions were involved in 46% of the cases. The median hematoma volume and depth were 36 mL (interquartile range [IQR], 27-65 mL) and 1.4 cm (IQR, 0.3-2.9 cm), respectively. The median time from ictus to surgery was 24.5 hours (IQR, 16-66 hours). The degree of hematoma evacuation was ≥90%, 75% to 89%, and 50% to 74% in 72%, 23%, and 5.0% of the patients, respectively. The median GCS score at discharge was 14 (range, 8-15). The improvement in GCS score was statistically significant (P < .001). Modified Rankin Scale data were available for 35 patients. Fifty-two percent of those patients had a modified Rankin Scale score of ≤2. There were no mortalities.

CONCLUSION: The approach was safely performed in all patients with a relatively high rate of clot evacuation and functional independence.

 

Posted on

Lateral Orbitotomy Approach for Lesions Involving the Middle Fossa

Neurosurgery 80:309–322, 2017

Classically used for treatment of orbital lesions,the lateral orbitotomy with cantholysis can be combined with a temporal craniectomy for lesions involving the middle cranial fossa.

OBJECTIVE: To present a single-center experience with the lateral orbitotomy approach for lesions involving the middle fossa.

METHODS: Twenty-five patients underwent lateral orbitotomies from April 2012 to July 2015. Excluding patients with solely intraorbital pathologies, 13 patients’clinical and radio- graphic records were retrospectively reviewed.

RESULTS: Signs/symptoms in the 13 patients (ages 28-81) included proptosis (69%), decreased visual acuity (31%), diplopia (54%), and afferent pupillary defect (69%). Pathologies were meningioma (8), esthesioneuroblastoma, lymphoma, chordoma, Ewing’s sarcoma, and squamous cell carcinoma. Surgical goals were maximal safe resection in 8 patients, palliative debulking in 3 patients, and cavernous sinus biopsy in 2 patients. In 8 patients for whom maximal resection was the goal, 2 had gross total resection, while 6 had near-total resection. All patients (3) for whom palliation was the goal had symptomatic improvement. Both cavernous sinus biopsies obtained diagnostic tissue without complications. All patients with proptosis (n = 9) and diplopia (n = 7), and 2 of 4 patients with decreased visual acuity had improvement in their symptoms. No patient reported worsening of their symptoms. Mean follow-up was 12 mo (2-30 mo). Complica- tions included oculorrhea (1), pseudomeningocele (2), transient ptosis (2), and forehead numbness (1).

CONCLUSION: The lateral orbitotomy is a promising approach for carefully selected lesions with involvement of both the lateral orbit and middle cranial fossa. It provides minimally invasive access for biopsy, decompression, or resection.

Posted on

Venous air embolism in the sitting position in cranial neurosurgery

Acta Neurochir (2017) 159:339–346

There is an ongoing debate about the sitting position (SP) in neurosurgical patients. The SP provides a number of advantages as well as severe complications such as commonly concerning venous air embolism (VAE). The best monitoring system for the detection of VAE is still controversial.

Methods: In this retrospective analysis we compared 208 patients. Transesophageal echocardiography (TEE) or transthoracic Doppler (TTD) were used as monitoring devices to detect VAE; 101 cases were monitored with TEE and 107 with TTD.

Results: The overall incidence of VAE was 23% (TTD: 10%; TEE: 37%), but the incidence of clinically relevant VAE (drop in end-tidal carbon dioxide above 3 mmHg) was higher in the TTD group (9 out of 17 VAE, 53%) compared to the TEE group (19 out of 62 VAE, 31%). None of the patients with recorded VAE had clinically significant sequelae.

Conclusions: In this small sample we found more VAE events in the TEE group, but the incidence of clinically relevant VAE was rare and comparable to other data. There is no consensus in the definition of clinically relevant VAE.

 

Posted on

Efficacy of the transtemporal approach with awake brain mapping to reach the dominant posteromedial temporal lesions

Acta Neurochir (2017) 159: 177

Surgeries for lesions in the dominant hippocampal and parahippocampal gyrus involving the posteromedial temporal regions are challenging to perform because they are located close to Wernicke’s area; white matter fibers related with language; the optic radiations; and critical neurovascular structures. We performed a transtemporal approach with awake functional mapping for lesions affecting the dominant posteromedial temporal regions. The aim of this study was to assess the feasibility, safety, and efficacy of awake craniotomy for these lesions.

Methods: We retrospectively reviewed four consecutive patients with tumors or cavernous angiomas located in the left hippocampal and parahippocampal gyrus, which further extended to the posteromedial temporal regions, who underwent awake surgery between December 2014 and January 2016.

Results: Four patients with lesions associated with the left hippocampal and parahippocampal gyrus, including the posteromedial temporal area, who underwent awake surgery were registered in the study. In all four patients, cortical and subcortical eloquent areas were identified via direct electrical stimulation. This allowed determination of the optimal surgical route to the angioma or tumor, even in the language-dominant hippocampal and parahippocampal gyrus. In particular, this approach enabled access to the upper part of posteromedial temporal lesions, while protecting the subcortical language-related fibers, such as the superior longitudinal fasciculus.

Conclusions: This study revealed that awake brain mapping can enable the safe resection of dominant posteromedial temporal lesions, while protecting cortical and subcortical eloquent areas. Furthermore, our experience with four patients demonstrates the feasibility, safety, and efficacy of awake surgery for these lesions.

Posted on

A randomized controlled trial comparing autologous cranioplasty with custom-made titanium cranioplasty

J Neurosurg 126:81–90, 2017

Autologous bone is usually used to reconstruct skull defects following decompressive surgery. However, it is associated with a high failure rate due to infection and resorption. The aim of this study was to see whether it would be cost-effective to use titanium as a primary reconstructive material.

Methods Sixty-four patients were enrolled and randomized to receive either their own bone or a primary titanium cranioplasty. All surgical procedures were performed by the senior surgeon. Primary and secondary outcome measures were assessed at 1 year after cranioplasty.

Results There were no primary infections in either arm of the trial. There was one secondary infection of a titanium cranioplasty that had replaced a resorbed autologous cranioplasty. In the titanium group, no patient was considered to have partial or complete cranioplasty failure at 12 months of follow-up (p = 0.002) and none needed revision (p = 0.053). There were 2 deaths unrelated to the cranioplasty, one in each arm of the trial. Among the 31 patients who had an autologous cranioplasty, 7 patients (22%) had complete resorption of the autologous bone such that it was deemed a complete failure. Partial or complete autologous bone resorption appeared to be more common among young patients than older patients (32 vs 45 years old, p = 0.013). The total cumulative cost between the 2 groups was not significantly different (mean difference A$3281, 95% CI $-9869 to $3308; p = 0.327).

Conclusions Primary titanium cranioplasty should be seriously considered for young patients who require reconstruction of the skull vault following decompressive craniectomy. Clinical trial registration no.: ACTRN12612000353897 (anzctr.org.au)

Posted on

Transulcal parafascicular minimally invasive approach to deep and subcortical cavernomas

J Neurosurg 125:1360–1366, 2016

Cavernomas comprise 8%–15% of intracranial vascular lesions, usually supratentorial in location and superficial. Cavernomas in the thalamus or subcortical white matter represent a unique challenge for surgeons in trying to identify and then use a safe corridor to access and resect the pathology.

Previous authors have described specific open microsurgical corridors based on pathology location, often with technical difficulty and morbidity.

This series presents 2 cavernomas that were resected using a minimally invasive approach that is less technically demanding and has a good safety profile. The authors report 2 cases of cavernoma: one in the thalamus and brainstem with multiple hemorrhages and the other in eloquent subcortical white matter. These lesions were resected through a transulcal parafascicular approach with a port-based minimally invasive technique.

In this series there was complete resection with no neurological complications. The transulcal parafascicular minimally invasive approach relies on image interpretation and trajectory planning, intraoperative navigation, cortical cannulation and subcortical space access, high-quality optics, and resection as key elements to minimize exposure and retraction and maximize tissue preservation. The authors applied this technique to 2 patients with cavernomas in eloquent locations with excellent outcomes.

 

Posted on

Microscopic versus endoscopic approaches for craniopharyngiomas

microscopic-versus-endoscopic-approaches-for-craniopharyngiomas

Neurosurg Focus 41 (6):E5, 2016

Resection remains the mainstay of treatment for craniopharyngiomas with the goal of radical resection, if safely possible, to minimize the rate of recurrence. Endoscopic endonasal and microscopic transcranial surgical approaches have both become standard methods for the treatment for craniopharyngiomas. However, the approach selection paradigm for craniopharyngiomas is still a point of discussion. Choosing the optimal surgical approach can play a significant role in maximizing the extent of resection and surgical outcome while minimizing the risks of potential complications.

Craniopharyngiomas can present with a variety of different sizes, locations, and tumor consistencies, and each individual tumor has distinct features that favor one specific approach over another.

The authors review standard cranial base techniques applied to craniopharyngioma surgery, using both the endoscopic endonasal approach and traditional open microsurgical approaches, and analyze factors involved in approach selection. They discuss their philosophy of approach selection based on the location and extent of the tumor on preoperative imaging as well as the advantages and limitations of each surgical corridor, and they describe the operative nuances of each technique, using a personalized, tailored approach to the individual patient with illustrative cases and videos.

Posted on

Laser interstitial thermal therapy followed by minimal-access transsulcal resection for the treatment of large and dif cult to access brain tumors

litt

Neurosurg Focus 41 (4):E14, 2016

Laser interstitial thermal therapy (LITT), sometimes referred to as “stereotactic laser ablation,” has demonstrated utility in a subset of high-risk surgical patients with dificult to access (DTA) intracranial neoplasms. However, the treatment of tumors larger than 10 cm3 is associated with suboptimal outcomes and morbidity. This may limit the utility of LITT in dealing with precisely those large or deep tumors that are most dif cult to treat with conventional approaches. Recently, several groups have reported on minimally invasive transsulcal approaches utilizing tubular retracting systems. However, these approaches have been primarily used for intraventricular or paraventricular lesions, and subtotal resections have been reported for intraparenchymal lesions. Here, the authors describe a combined approach of LITT followed by minimally invasive transsulcal resection for large and DTA tumors.

Methoss The authors retrospectively reviewed the results of LITT immediately followed by minimally invasive, trans-sulcal, transportal resection in 10 consecutive patients with unilateral, DTA malignant tumors > 10 cm3. The patients, 5 males and 5 females, had a median age of 65 years. Eight patients had glioblastoma multiforme (GBM), 1 had a previously treated GBM with radiation necrosis, and 1 had a melanoma brain metastasis. The median tumor volume treated was 38.0 cm3.

Results The median tumor volume treated to the yellow thermal dose threshold (TDT) line was 83% (range 76%– 92%), the median tumor volume treated to the blue TDT line was 73% (range 60%–87%), and the median extent of resection was 93% (range 84%–100%). Two patients suffered mild postoperative neurological de cits, one transiently. Four patients have died since this analysis and 6 remain alive. Median progression-free survival was 280 days, and median overall survival was 482 days.

Conclusions Laser interstitial thermal therapy followed by minimally invasive transsulcal resection, reported here for the first time, is a novel option for patients with large, DTA, malignant brain neoplasms. There were no unexpected neurological complications in this series, and operative characteristics improved as surgeon experience increased. Further studies are needed to elucidate any differences in survival or quality of life metrics.

Posted on

Unilateral endonasal transcribriform approach with septal transposition for olfactory groove meningioma: can olfaction be preserved?

unilateral-endonasal-transcribriform-approach-with-septal-transposition-for-olfactory-groove-meningioma-can-olfaction-be-preserved

Acta Neurochir (2016) 158:1965–1972

Loss of olfaction has been considered inevitable in endoscopic endonasal resection of olfactory groove meningiomas. Olfaction preservation may be feasible through an endonasal unilateral transcribriform approach, with the option for expansion using septal transposition and contralateral preservation of the olfactory apparatus.

Methods An expanded unilateral endonasal transcribriform approach with septal transposition was performed in five cadaver heads. The approach was applied in a surgical case of a 24 × 26-mm olfactory groove meningioma originating from the right cribriform plate with partially intact olfaction.

Results The surgical approach offered adequate exposure to the anterior skull base bilaterally. The nasal/septal mucosa was preserved on the contralateral side. Gross total resection of the meningioma was achieved with the successful preservation of the contralateral olfactory apparatus and preoperative olfaction. Six months later, the left nasal cavity showed no disruption of the mucosal lining and the right side was at the appropriate stage of healing for a harvested nasoseptal flap. One year later, the preoperative olfactory function was intact and favorably viewed by the patient. Objective testing of olfaction showed microsomia.

Conclusions Olfaction preservation may be feasible in the endoscopic endonasal resection of a unilateral olfactory groove meningioma through a unilateral transcribriform approach with septal transposition and preservation of the contralateral olfactory apparatus.

Proudly powered by WordPress