Category: Surgical technique

Posted on

Revisiting the rules for freehand ventriculostomy: a virtual reality analysis

J Neurosurg 128:1250–1257, 2018

Frontal ventriculostomy is one of the most frequent and standardized procedures in neurosurgery. However, many first and subsequent punctures miss the target, and suboptimal placement or misplacement of the catheter is common. The authors therefore reexamined the landmarks and rules to determine the entry point and trajectory with the best hit rate (HtR).

METHODS The authors randomly selected CT scans from their institution’s DICOM pool that had been obtained in 50 patients with normal ventricular and skull anatomy and without ventricular puncture. Using a 5 × 5–cm frontal grid with 25 entry points referenced to the bregma, the authors examined trajectories 1) perpendicular to the skull, 2) toward classic facial landmarks in the coronal and sagittal planes, and 3) toward an idealized target in the middle of the ipsilateral anterior horn (ILAH). Three-dimensional virtual reality ventriculostomies were simulated for these entry points; trajectories and the HtRs were recorded, resulting in an investigation of 8000 different virtual procedures.

RESULTS The best HtR for the ILAH was 86% for an ideal trajectory, 84% for a landmark trajectory, and 83% for a 90° trajectory, but only at specific entry points. The highest HtRs were found for entry points 3 or 4 cm lateral to the midline, but only in combination with a trajectory toward the contralateral canthus; and 1 or 2 cm lateral to the midline, but only paired with a trajectory toward the nasion. The same “pairing” exists for entry points and trajectories in the sagittal plane. For perpendicular (90°) trajectories, the best entry points were at 3–5 cm lateral to the midline and 3 cm anterior to the bregma, or 4 cm lateral to the midline and 2 cm anterior to the bregma.

CONCLUSIONS Only a few entry points offer a chance of a greater than 80% rate of hitting the ILAH, and then only in combination with a specific trajectory. This “pairing” between entry point and trajectory was found both for landmark targeting and for perpendicular trajectories, with very limited variability. Surprisingly, the ipsilateral medial canthus, a commonly reported landmark, had low HtRs, and should not be recommended as a trajectory target.

 

 

Posted on

Role of electrophysiology in guiding near-total resection for preservation of facial nerve function in the surgical treatment of large vestibular schwannomas

J Neurosurg 128:903–910, 2018

In large vestibular schwannoma (VS) surgery, the facial nerve (FN) is at high risk of injury. Near-total resection has been advocated in the case of difficult facial nerve dissection, but the amount of residual tumor that should be left and when dissection should be stopped remain controversial factors. The objective of this study was to report FN outcome and radiological results in patients undergoing near-total VS resection guided by electromyographic supramaximal stimulation of the FN at the brainstem.

METHODS This study was a retrospective analysis of a prospectively maintained database. Inclusion criteria were surgical treatment of a large VS during 2014, normal preoperative FN function, and an incomplete resection due to the strong adherence of the tumor to the FN and the loss of around 50% of the response of supramaximal stimulation of the proximal FN at 2 mA. Facial nerve function and the amount and evolution of the residual tumor were evaluated by clinical examination and by MRI at a mean of 5 days postoperatively and at 1 year postoperatively.

RESULTS Twenty-five patients met the inclusion criteria and were included in the study. Good FN function (Grade I or II) was observed in 16 (64%) and 21 (84%) of the 25 patients at Day 8 and at 1 year postoperatively, respectively. At the 1-year follow-up evaluation (n = 23), 15 patients (65%) did not show growth of the residual tumor, 6 patients (26%) had regression of the residual tumor, and only 2 patients (9%) presented with tumor progression.

CONCLUSIONS Near-total resection guided by electrophysiology represents a safe option in cases of difficult dissection of the facial nerve from the tumor. This seems to offer a good compromise between the goals of preserving facial nerve function and achieving maximum safe resection.

Posted on

Selective amygdalohippocampectomy via a navigated temporobasal approach, when veins forbid elevation of the temporal lobe.jpg

Acta Neurochir (2018) 160:597–601

Selective amygdalohippocampectomy is an effective treatment option for mesial temporal lobe epilepsy associated with hippocampal sclerosis.

Methods To describe and emphasize potential pitfalls during selective amygdalohippocampectomy via a modified navigated temporobasal approach, in cases, where temporal basal veins hinder the required elevation of the temporal lobe.

Conclusions Selective amygdalohippocampectomy via navigated temporobasal approach is a safe procedure that can reduce the rate of visual field deficits by avoiding damage of optic radiation. The option of a small subpial corticotomy of the inferior temporal gyrus allows sufficient elevation of the temporal lobe in cases with difficult basal venous anatomy.

Keywords

Posted on

Risk assessment of motor function using nTMS-based tractography

J Neurosurg 128:800–810, 2018

Navigated transcranial magnetic stimulation (nTMS) and diffusion tensor imaging fiber tracking (DTI FT) based on nTMS data are increasingly used for preoperative planning and resection guidance in patients suffering from motor-eloquent brain tumors. The present study explores whether nTMS-based DTI FT can also be used for individual preoperative risk assessment regarding surgery-related motor impairment.

METHODS Data derived from preoperative nTMS motor mapping and subsequent nTMS-based tractography in 86 patients were analyzed. All patients suffered from high-grade glioma (HGG), low-grade glioma (LGG), or intracranial metastasis (MET). In this context, nTMS-based DTI FT of the corticospinal tract (CST) was performed at a range of fractional anisotropy (FA) levels based on an individualized FA threshold ([FAT]; tracking with 50%, 75%, and 100% FAT), which was defined as the highest FA value allowing for visualization of fibers (100% FAT). Minimum lesion-to-CST distances were measured, and fiber numbers of the reconstructed CST were assessed. These data were then correlated with the preoperative, postoperative, and follow-up status of motor function and the resting motor threshold (rMT).

RESULTS At certain FA levels, a statistically significant difference in lesion-to-CST distances was observed between patients with HGG who had no impairment and those who developed surgery-related transient or permanent motor deficits (75% FAT: p = 0.0149; 100% FAT: p = 0.0233). In this context, no patient with a lesion-to-CST distance ≥ 12 mm suffered from any new surgery-related permanent paresis (50% FAT and 75% FAT). Furthermore, comparatively strong negative correlations were observed between the rMT and lesion-to-CST distances of patients with surgery-related transient paresis (Spearman correlation coefficient [rs]; 50% FAT: rs = –0.8660; 75% FAT: rs = –0.8660) or surgery-related permanent paresis (50% FAT: rs = –0.7656; 75% FAT: rs = –0.6763).

CONCLUSIONS This is one of the first studies to show a direct correlation between imaging, clinical status, and neurophysiological markers for the integrity of the motor system in patients with brain tumors. The findings suggest that nTMSbased DTI FT might be suitable for individual risk assessment in patients with HGG, in addition to being a surgery-planning tool. Importantly, necessary data for risk assessment were obtained without significant additional efforts, making this approach potentially valuable for direct clinical use.

Posted on

Frontal Keyhole Craniotomy for Resection of Low- and High-Grade Gliomas

Neurosurgery 82:388–396, 2018

Minimally invasive techniques are increasingly being used to access intraaxial brain lesions.

OBJECTIVE: To describe a method of resecting frontal gliomas through a keyhole craniotomy and share the results with these techniques.

METHODS: We performed a retrospective review of data obtained on all patients undergoing resection of frontal gliomas by the senior author between 2012 and 2015.We describe our technique for resecting dominant and nondominant gliomas utilizing both awake and asleep keyhole craniotomy techniques.

RESULTS: After excluding 1 patient who received a biopsy only, 48 patients were included in the study. Twenty-nine patients (60%) had not received prior surgery. Twenty-six patients (54%) were diagnosed with WHO grade II/III tumors, and 22 patients (46%) were diagnosedwith glioblastoma. Twenty-five cases (52%)were performed awake.At least 90% of the tumor was resected in 35 cases (73%). Three of 43 patients with clinical follow-up experienced permanent deficits.

CONCLUSION: We provide our experience in using keyhole craniotomies for resecting frontal gliomas. Our data demonstrate the feasibility of using minimally invasive techniques to safely and aggressively treat these tumors.

Posted on

Fully endoscopic combined transsphenoidal and supraorbital keyhole approach for parasellar lesions

J Neurosurg 128:685–694, 2018

Parasellar tumors that extend far laterally beyond the internal carotid artery or that are fibrous and adhere firmly to critical structures are difficult to remove totally via the endoscopic transsphenoidal approach alone. In such cases, a combined transsphenoidal-transcranial approach is effective to achieve maximal resection in a single stage. In this paper, a new minimally invasive surgical technique for complicated parasellar lesions, a fully endoscopic combined transsphenoidal–supraorbital keyhole approach, is presented.

METHODS A retrospective review of patients who had been treated via a fully endoscopic combined transsphenoidal– supraorbital keyhole approach for complicated parasellar lesions was performed. The data for resection rate, perioperative mortality and morbidity, and postoperative outcomes were analyzed.

RESULTS A total of 12 fully endoscopic combined transsphenoidal–supraorbital keyhole approaches were performed from March 2013 to February 2016; 10 were for pituitary adenomas and 2 were for craniopharyngiomas. Gross-total resection or near-total resection was achieved in 7 of 12 cases. Among the 11 patients who had presented with preoperative visual disturbances, 7 had visual improvement. However, 1 patient showed deterioration in visual function. No patient experienced postoperative hemorrhage, needed additional surgical treatment, or had postoperative CSF leakage.

CONCLUSIONS In the combined transsphenoidal and transcranial approach, safe and effective cooperative manipulation with 2 surgical corridors can be performed for complicated parasellar lesions. The goal of this procedure is not to achieve gross-total resection, but to achieve safe resection. Moreover, this new surgical approach offers neurosurgeons a simpler operative field with less invasiveness than the conventional microscopic combined approach. The fully endoscopic combined endonasal–supraorbital keyhole approach is an efficacious procedure for complicated parasellar lesions with acceptable results.

 

Posted on

Fronto-orbitozygomatic approach: functional and cosmetic outcomes in a series of 169 patients

J Neurosurg 128:466–474, 2018

Advantages of the fronto-orbitozygomatic (FOZ) approach have been reported extensively in the literature; nevertheless, restoration of normal anatomy and the esthetic impact of surgery are increasingly important issues for patients and neurosurgeons. The aim of this study was to analyze functional and cosmetic outcomes in a series of 169 patients with different pathologies who underwent surgery in which the FOZ approach was used.

METHODS Between January 2000 and December 2014, 250 consecutive patients underwent surgery with an FOZ approach as the primary surgical treatment. Follow-up data were available for only 169 patients; 103 (60.9%) of these patients were female and 66 (39.1%) were male, and their ages ranged from 6 to 77 years (mean 46.9 years; SD 15.6 years). Mean follow-up time was 66 months (range 6–179 months; SD 49.5 months). Evaluation of clinical outcomes was performed with a focus on 4 main issues: surgical complications, functional outcome, cosmetic outcome, and patient satisfaction. The additional time needed to perform orbitotomy and orbital reconstruction was also evaluated.

RESULTS The permanent postoperative complications included forehead hypesthesia (41.4%) and dysesthesia (15.3%), frontal muscle weakness (10.3%), exophthalmos (1.4%), enophthalmos (4.1%), diplopia (6.6%; 2% were related to surgical approach), and persistent periorbital and eyelid swelling (3%). Approximately 90% of the patients reported subjectively that surgery did not affect their quality of life or complained of only minor problems that did not influence their quality of life significantly. The mean time needed for orbitotomy and orbital reconstruction was approximately half an hour.

CONCLUSIONS Comprehensive knowledge of the potential complications and overall clinical outcomes of the FOZ approach can be of great utility to neurosurgeons in balancing the well-known benefits of the approach with potential additional morbidities.

 

Posted on

Transcondylar approach for resection of lateral medullary cavernous malformation

Acta Neurochir (2018) 160:291–294

Resection of a medullary cavernous malformation requires aggressive exposure, but there is controversy on how much occipital condyle can be safely removed during the transcondylar approach.

Method We describe and demonstrate the use of the transcondylar approach to a medullary cavernous malformation, with emphasis on adequate surgical exposure while preserving the atlanto-occipital joint.

Conclusions Despite conservative handling of the occipital condyle, craniocervical stability may vary in patients after transcondylar surgery. A “dynamic” computer tomography, with views of the atlanto-occipital joint at each end-rotational extreme, may be the best postoperative assessment tool to evaluate the stability of the craniocervical junction.

Posted on

Surgical approach to posterior inferior cerebellar artery aneurysms

Acta Neurochir (2018) 160:295–299

The far-lateral is a standardised approach to clip aneurysms of the posterior inferior cerebellar artery (PICA). Different variants can be adopted to manage aneurysms that differ in morphology, topography, ruptured status, cerebellar swelling and surgeon preference.

Method We distinguished five paradigmatic approaches aimed to manage aneurysms that are: proximal unruptured; proximal ruptured requiring posterior fossa decompression (PFD); proximal ruptured not requiring PFD; distal unruptured; distal ruptured.

Conclusions Preoperative planning in the setting of PICA aneurysm surgery is of paramount importance to perform an effective and safe procedure, to ensure an adequate PFD and optimal proximal control before aneurysm manipulation.

Posted on

Endoscopic microvascular decompression for hemifacial spasm associated with the vertebral artery

Acta Neurochir (2018) 160:157–159

Microvascular decompression (MVD) of hemifacial spasm (HFS) associated with the vertebral artery (VA) shows higher rates of incomplete cure and complications compared to non-VA-related HFS.

Method Purely endoscopic MVD for VA-associated HFS via a retrosigmoid keyhole was performed. Neurovascular conflicts by a directly offending artery and VA around the root exit zone of the facial nerve were clearly demonstrated under 30° endoscopic view without significant cerebellar retraction. The VA and directly offending artery were safely transposed with preservation of perforators under excellent view.

Conclusion Endoscopic MVD offers reliable decompression for VA-associated HFS with minimal invasiveness.

Posted on

Anterior interhemispheric transsplenial approach to pineal region tumors

J Neurosurg 128:182–192, 2018

Pineal region tumors are challenging to access because they are centrally located within the calvaria and surrounded by critical neurovascular structures.

The goal of this work is to describe a new surgical trajectory, the anterior interhemispheric transsplenial approach, to the pineal region and falcotentorial junction area. To demonstrate this approach, the authors examined 7 adult formalin-fixed silicone-injected cadaveric heads and 2 fresh human brain specimens.

One representative case of falcotentorial meningioma treated through an anterior interhemispheric transsplenial approach is also described.

Among the interhemispheric approaches to the pineal region, the anterior interhemispheric transsplenial approach has several advantages. 1) There are few or no bridging veins at the level of the pericoronal suture. 2) The parietal and occipital lobes are not retracted, which reduces the chances of approach-related morbidity, especially in the dominant hemisphere. 3) The risk of damage to the deep venous structures is low because the tumor surface reached first is relatively vein free. 4) The internal cerebral veins can be manipulated and dissected away laterally through the anterior interhemispheric route but not via the posterior interhemispheric route. 5) Early control of medial posterior choroidal arteries is obtained.

The anterior interhemispheric transsplenial approach provides a safe and effective surgical corridor for patients with supratentorial pineal region tumors that 1) extend superiorly, involve the splenium of the corpus callosum, and push the deep venous system in a posterosuperior or an anteroinferior direction; 2) are tentorial and displace the deep venous system inferiorly; or 3) originate from the splenium of the corpus callosum.

 

Posted on

Chiari I malformation: surgical technique, indications and limits

Acta Neurochir (2018) 160:213–217

Chiari malformation type I (CM-I) is a rare disease characterised by herniation of cerebellar tonsils below the foramen magnum with associated anomalies of posterior fossa. We describe here the surgical technique, indications and limits of surgical treatment.

Method The authors describe the surgical technique, including: posterior fossa decompression, opening of the foramen of Magendie and duraplasty in case of CM-I.

Conclusions Posterior fossa decompression plus duraplasty is a safe and effective procedure for patients with CM-I malformation.

Posted on

Lumbar Disk Arthroplasty for Degenerative Disk Disease

World Neurosurg. (2018) 109:188-196.

Low back pain is the principal cause of long-term disability worldwide. We intend to address one of its main causes, degenerative disk disease, a spinal condition involving degradation of an intervertebral disk.

Following unsuccessful conservative treatment, patients may be recommended for surgery. The two main surgical treatments for lumbar degenerative disk disease are lumbar fusion: traditional standard surgical treatment and lumbar disk arthroplasty, also known as lumbar total disk replacement. Lumbar fusion aims to relieve pain by fusing vertebrae together to eliminate movement at the joint, but it has been criticized for problems involving insignificant pain relief, a reduced range of motion, and an increased risk of adjacent segment degeneration. This leads to development of the lumbar total disk replacement technique, which aims to relieve pain replacing a degenerated intervertebral disk with a moveable prosthesis, thus mimicking the functional anatomy and biomechanics of a native intervertebral disk. Over the years a large range of prosthetic disks has been developed.

The efficacy and current evidence for these prostheses are discussed in this review. The results of this study are intended to guide clinical practice and future lumbar total disk replacement device choice and design.

Posted on

Clinical and radiological results of posterior cervical foraminotomy at two or three levels: a 3-year follow-up

Acta Neurochir (2017) 159:2369–2377

Single-level unilateral posterior cervical foraminotomy is regarded as a safe method. However, the outcomes of posterior cervical foraminotomy performed on two or three levels are uncertain and debated. We aimed to analyze the long-term clinical and radiological outcomes of posterior cervical foraminotomy at two or three levels.

Methods From September 2008 to December 2011, a total of 42 patients who underwent a posterior cervical foraminotomy at two or three levels and were followed for at least 3 years were analyzed with retrospective cohort study. Clinical assessments were performed using the visual analog scale (VAS), neck disability index (NDI) and modified MacNab criteria. Radiological evaluation included the assessment of static and dynamic lateral radiographs to identify instability, postlaminectomy kyphotic deformity, adjacent segmental degeneration (ASD), and focal degeneration.

Results The mean VAS improved from preoperative score 8.5 ± 0.3 to postoperative score 1.8 ± 0.5 significantly. The mean presenting NDI score was 32.9 ± 2.0 and the mean postoperative NDI score was 14.2 ± 1.3. Improvement of radiculopathy was displayed in 39 patients (92.9%). During radiological evaluation, no significant change in disc height related to ASD and focal degeneration was noted. However, we confirmed one patient with radiological instability and one patient with radiological postlaminectomy kyphotic deformity.

Conclusions Posterior cervical foraminotomy at two or three levels is fairly effective for treating patients with cervical radiculopathy, and results in long-lasting pain relief and improved quality of life in nearly all patients. However, further studies of three levels that include more patients are needed.

Posted on

Efficacy and outcomes of facial nerve–sparing treatment approach to cerebellopontine angle meningiomas

J Neurosurg 127:1231–1241, 2017

Advanced microsurgical techniques contribute to reduced morbidity and improved surgical management of meningiomas arising within the cerebellopontine angle (CPA). However, the goal of surgery has evolved to preserve the quality of the patient’s life, even if it means leaving residual tumor. Concurrently, Gamma Knife radiosurgery (GKRS) has become an acceptable and effective treatment modality for newly diagnosed, recurrent, or progressive meningiomas of the CPA. The authors review their institutional experience with CPA meningiomas treated with GKRS, surgery, or a combination of surgery and GKRS. They specifically focus on rates of facial nerve preservation and characterize specific anatomical features of tumor location with respect to the internal auditory canal (IAC).

METHODS Medical records of 76 patients with radiographic evidence or a postoperative diagnosis of CPA meningioma, treated by a single surgeon between 1992 and 2016, were retrospectively reviewed. Patients with CPA meningiomas smaller than 2.5 cm in greatest dimension were treated with GKRS, while patients with tumors 2.5 cm or larger underwent facial nerve–sparing microsurgical resection where appropriate. Various patient, clinical, and tumor data were gathered. Anatomical features of the tumor origin as seen on preoperative imaging confirmed by intraoperative investigation were evaluated for prognostic significance. Facial nerve preservation rates were evaluated.

RESULTS According to our treatment paradigm, 51 (67.1%) patients underwent microsurgical resection and 25 (32.9%) patients underwent GKRS. Gross-total resection (GTR) was achieved in 34 (66.7%) patients, and subtotal resection (STR) in 17 (33.3%) patients. Tumors recurred in 12 (23.5%) patients initially treated surgically, requiring additional surgery and/or GKRS. Facial nerve function was unchanged or improved in 68 (89.5%) patients. Worsening facial nerve function occurred in 8 (10.5%) patients, all of whom had undergone microsurgical resection. Upfront treatment with GKRS for CPA meningiomas smaller than 2.5 cm was associated with preservation of facial nerve function in all patients over a median follow-up of 46 months, regardless of IAC invasion and tumor origin. Anatomical origin was associated with extent of resection but did not correlate with postoperative facial nerve function. Tumor size, extent of resection, and the presence of an arachnoid plane separating the tumor and the contents of the IAC were associated with postoperative facial nerve outcomes.

CONCLUSIONS CPA meningiomas remain challenging lesions to treat, given their proximity to critical neurovascular structures. GKRS is a safe and effective option for managing CPA meningiomas smaller than 2.5 cm without associated mass effect or acute neurological symptoms. Maximal safe resection with preservation of neurological function can be performed for tumors 2.5 cm or larger without significant risk of facial nerve dysfunction, and, when combined with GKRS for recurrence and/or progression, provides excellent disease control. Anatomical features of the tumor origin offer critical insights for optimizing facial nerve preservation in this cohort.

Posted on

The medial orbito-frontal approach for orbital tumors

Acta Neurochir (2017) 159:2223–2227

A variety of lesions can affect the orbit. Surgical approaches must be available to provide 360 degrees of access. For tumors occupying the superomedial intraconal quadrant, there is a rationale to selecting the medial orbito-frontal approach.

Methods This article outlines the relevant surgical anatomy and the different surgical steps of this approach.

Results The medial orbito-frontal approach offers a full exposure of the superomedial intraconal quadrant and avoids crossing the plane of the optic nerve.

Conclusion In selected intraconal tumor cases, this transcranial epidural intraorbital approach is a straightforward corridor through reliable landmarks that can be routinely performed.

Posted on

The superior fovea triangle approach: a novel safe entry zone to the brainstem

J Neurosurg 127:1134–1138, 2017

The authors describe a safe entry zone, the superior fovea triangle, on the floor of the fourth ventricle for resection of deep dorsal pontine lesions at the level of the facial colliculus.

Clinical data from a patient undergoing a suboccipital telovelar transsuperior fovea triangle approach to a deep pontine cavernous malformation were reviewed and supplemented with 6 formalin-fixed adult human brainstem and 2 silicone-injected adult human cadaveric heads using the fiber dissection technique to illustrate the utility of this novel safe entry zone.

The superior fovea has a triangular shape that is an important landmark for the motor nucleus of the trigeminal, abducens, and facial nerves. The inferior half of the superior fovea triangle may be incised to remove deep dorsal pontine lesions through the floor of the fourth ventricle.

The superior fovea triangle may be used as a safe entry zone for dorsally located lesions at the level of the facial colliculus.

Posted on

Microvascular Decompression for Trigeminal Neuralgia Using a Novel Fenestrated Clip and Tentorial Flap Technique

WORLD NEUROSURGERY 106: 775-784, 2017

Microvascular decompression (MVD) for neurovascular compression syndromes, such as trigeminal neuralgia and hemifacial spasm, has been traditionally described as an interposing technique using Teflon. Some alternative interposing materials have been proposed. In addition, transposing techniques have been increasingly reported as an alternative with a potentially lower recurrence rate and fewer complications.

OBJECTIVE: To describe our experience with a technique consisting of transposition of the superior cerebellar artery using a fenestrated clip and a tentorial flap in patients with trigeminal neuralgia.

METHODS: We describe a novel transposing technique using a fenestrated clip and a tentorial flap in patients with neurovascular compression. An illustrative case is provided of an 83-year-old female patient who complained of a 4-year history of left trigeminal neuralgia caused by compression by the superior cerebellar artery who was treated with this technique. Furthermore, a thorough review of the literature is presented. –

RESULTS: The patient underwent the procedure with the proposed technique without complication. Both the surgery and the postoperative course were uneventful. The patient remains asymptomatic 1 year after the procedure.

CONCLUSION: We propose a novel technique for the treatment of trigeminal neuralgia, eliminating the need for padding the vessel with a foreign body. This technique can be applied successfully in selected cases of neurovascular compression syndromes.

Posted on

Complex Internal Carotid Artery Aneurysm Treated by Extracranial to Intracranial Bypass Using High-Flow Grafts with Therapeutic Internal Carotid Artery Occlusion

Neurosurgery 81:672–679, 2017

Although the extracranial-to-intracranial high-flow bypass (EC-IC HFB) continues to be indispensable for complex aneurysms, the risk factors for the graft occlusion and whether the graft size changes after the bypass have not been well established.

OBJECTIVE: To evaluate the risk factors for the graft occlusion and to confirm whether graft diameters changed over time.

METHODS: The data of 75 patients who suffered from complex internal carotid artery (ICA) aneurysms and were treated by EC-IC HFB using radial artery graft (RAG) or saphenous vein graft (SVG) with therapeutic ICA occlusion were evaluated. Clinical and radiological characteristics were compared in patients with and without the graft occlusion by the logrank test. Graft diameters measured preoperatively, postoperatively, at 6 months, and at 1 year were compared by paired t-test.

RESULTS: During a follow-up period (median 26.2 months), graft occlusions were seen in 4 patients (5.3%), and these were the SVGs. Only SVG was related to graft occlusion (P<.001). There was a significant increase with time in RAG diameters (preoperative, 3.1 ± 0.41 mm; postoperative, 3.6 ± 0.65 mm; 6 months, 4.3 ± 1.0 mm; 1 year, 4.4 ± 1.0 mm), while there were no significant diameter changes in SVGs.

CONCLUSION: The present study showed that the SVG was related to the graft occlusion and RAGs gradually enlarged. Unless Allen test is negative, RAG may be better to be used as a graft in EC-IC HFB if therapeutic ICA occlusion is needed.

Posted on

Epilepsy Surgeries Requiring an Operculoinsular Cortectomy

Neurosurgery 81:602–612, 2017

Epilepsy surgeries requiring an operculoinsulectomy pose significant difficulties because the perisylvian area is highly vascular, deep, and functional.

OBJECTIVE: To report the operative technique and results of epilepsy surgeries requiring an operculoinsular cortectomy at our institution.

METHODS: The data of all consecutive patients who had undergone an epilepsy surgery requiring an operculoinsular cortectomy with a minimum follow-up of 1 yr were reviewed. Tumor and vascular malformation cases were excluded. Surgical techniques are described based on findings during surgery.

RESULTS: Twenty-five patients underwent an epilepsy surgery requiring an operculoinsular cortectomy: mean age at surgery was 35 y (9-51), mean duration of epilepsy was 19 y (5-36), 14were female, and mean duration of follow-up was 4.7 y (1-16).Magnetic resonance imaging of the operculoinsular area was normal or revealed questionable nonspecific findings in 72% of cases. Investigation with intracranial EEG electrodes was done in 17 patients. Surgery was performed on the dominant side for language in 7 patients. An opercular resectionwasperformed inallbut2patientswhoonlyhadan insulectomy.Engel class I seizure control was achieved in 80% of patients. Postoperative neurological deficits (paresis, dysphasia, alteration of taste, smell, hearing, pain, and thermal perceptions) were frequent (75%) but always transient except for 1 patient with persistent mild alteration of thermal and pain perception.

CONCLUSION: Surgical treatment of operculoinsular epilepsy is effective in achieving seizure control and is associated with an acceptable long-term complication rate.

Proudly powered by WordPress