Month: April 2015

Posted on

DTI-MRI biomarkers in the search for normal pressure hydrocephalus aetiology

DTI chronic hydro

Neurosurg Rev (2015) 38:239–244

Normal pressure hydrocephalus (NPH) is a clinical syndrome characterized by gait disturbances, urinary incontinence and dementia. Clinical presentation overlaps with Alzheimer disease (AD).Early recognition thus early intervention (shunting) is important for successful treatment, but lack of a diagnostic test with sufficient sensitivity and specificity complicates the diagnosis.

We performed literature search and composed a structured review of imaging biomarkers of NPH. Morphometric studies are not sufficient to diagnose NPH. Hydrocephalus is a common finding in elderly people due to the symmetric brain atrophy and is even more pronounced in patients with AD. The key MRI biomarker seems to be diffusion tensor imaging (DTI). According to recent studies, the DTI analysis of the splenium corporis callosi, posterior limb of internal capsule, hippocampus and fornix combined with measurement of Evans index is a promising MRI biomarker of NPH and could be used for NPH diagnostics and in the differential diagnosis from AD and other dementias.

Posted on

Stereotactic Radiosurgery for Intracranial Meningiomas: Current Concepts and Future Perspectives

Stereotactic Radiosurgery for Intracranial Meningiomas- Current Concepts and Future Perspectives

Neurosurgery 76:362–371, 2015

Meningiomas are among the most common adult brain tumors. Although the optimal management of meningiomas would provide complete elimination of the lesion, this cannot always be accomplished safely through resection. Therefore, other therapeutic modalities, such as stereotactic radiosurgery (as primary or adjunctive therapy), have emerged.

In the current review, we have provided an overview of the historical outcomes of various radiosurgical modalities applied in the management of meningiomas. Furthermore, we provide a discussion on key factors (eg World Health Organization grade, lesion size, and lesion location) that affect tumor control and adverse event rates. We discuss recent changes in our understanding of meningiomas, based on molecular and genetic markers, and how these will change our perspective on the management of meningiomas.

We conclude by outlining the areas in which knowledge gaps persist and provide suggestions as to how these can be addressed.

Posted on

The role of microscope-integrated near-infrared indocyanine green videoangiography in the surgical treatment of intracranial dural arteriovenous fistulas

The role of microscope-integrated near-infrared indocyanine green videoangiography in the surgical treatment of intracranial dural arteriovenous fistulas

J Neurosurg 122:876–882, 2015

The successful treatment of an intracranial dural arteriovenous fistula (dAVF) requires complete obliteration of blood flow through the fistulous point. Surgical ligation is often used along with endovascular techniques. Digital subtraction angiography (DSA) can be used to confirm fistula obliteration; however, this technique can be cumbersome intraoperatively and difficult to correlate anatomically with the surgical field. Near-infrared indocyanine green (ICG) videoangiography has been described as a complementary tool for this purpose.

Methods The authors examined intracranial dAVF cases in which microscope-integrated intraoperative ICG videoangiography was used to identify and/or confirm obliteration of the dAVF during surgery. Retrospective evaluation of all intracranial dAVF cases treated with surgical ligation over a 10-year period at the Barrow Neurological Institute (n = 47) revealed 28 cases in which ICG videoangiography was used. The results were compared with findings on preoperative and intraoperative or postoperative DSA.

Results ICG videoangiography successfully confirmed the fistulous point intraoperatively in 96% (22/23) of the cases. It also revealed complete obliteration of fistulas, comparable to intraoperative or postoperative DSA, in 91% (21/23) of the cases. The false-negative rate of ICG was 8.7% (2/23), which is similar to the false-negative rate of intraoperative DSA alone (10.5% [2/19]).

Conclusions Microscope-based ICG videoangiography provides real-time information about the intraoperative anatomy of dAVFs. In addition, it can confirm complete obliteration of a fistula. This technique may be useful during dAVF surgery as an independent form of angiography or as an adjunct to intraoperative or postoperative DSA.

Posted on

Epidural spinal cord stimulation for neuropathic pain

Spinal_Cord_Stimulation_Devices_clip_image010

Acta Neurochir (2015) 157:739–741

Spinal cord stimulation (SCS) is a technique used worldwide to treat several types of chronic neuropathic pain refractory to any conservative treatment. The aim of this data collection is to enforce evidence of SCS effectiveness on neuropathic chronic pain reported in the literature and to speculate on the usefulness of the trial period in determining the long–term efficacy. Moreover, the very low percentage of undesired side effects and complications reported in our case series suggests that all implants should be performed by similarly well-trained and experienced professionals.

Method A multicentric data collection on a common database from 11 Italian neurosurgical departments started 3years ago. Two different types of electrodes (paddle or percutaneous leads) were used. Of 122 patients, 73 % (N=89) were submitted to a trial period, while the remaining patients underwent the immediate permanent implant (N=33). Statistical comparisons of continuous variables between groups were performed.

Results Most of the patients (80 %) had predominant pain to their lower limbs, while only 17 % of patients had prevalent axial pain. Significant reduction in pain, as measured by variation in visual analogue scale (VAS) score, was observed at least 1 year after implantation in 63.8%of the cases, 59.5%of patients who underwent a test trial and 71.4% of patients who underwent permanent implant at once. No statistical differences were found between the lower-limb pain group and the axial pain group.

Conclusions No relevant differences in long-term outcomes were observed in previously tested patients compared with patients implanted at once. Through this analysis we hope to recruit new centres, to give more scientific value to our results.

Posted on

The transmaxillary endoscopic approach to the inferior part of the orbit

The transmaxillary endoscopic approach to the inferior part

Acta Neurochir (2015) 157:625–628

Transmaxillary endoscopic approach to the inferior part of the orbit was demonstrated on cadaveric preparations; however, its clinical application has not been reported. We describe a clinically useful technique of the transmaxillary approach to the lower orbit.

Methods A four-hand technique is essential for extensive preparation within the orbit; therefore, the tools have to be introduced into the maxillary sinus through two ports: either through the canine fossa and antrostomy or through antrostomy using the bi-nostril transseptal approach.

Conclusion Intraorbital pathologies located in the inferior retrobulbar space can be successfully operated on using the transmaxillary endoscopic approach.

Posted on

Stratification of Recanalization for Patients With Endovascular Treatment of Intracranial Aneurysms

Recanalization for Patients With Endovascular Treatment of Intracranial Aneurysms

Neurosurgery 76:390–395, 2015

With the increasing use of endovascular techniques in the treatment of both ruptured and unruptured intracranial aneurysms, the issue of obliteration efficacy has become increasingly important.

OBJECTIVE: To systematically develop a comprehensive model for predicting retreatment with various types of endovascular treatment.

METHODS: We retrospectively reviewed medical records that were prospectively collected for 305 patients who received endovascular treatment for intracranial aneurysms from 2007 to 2013. Multivariable logistic regression was performed on candidate predictors identified by univariable screening analysis to detect independent predictors of retreatment. A composite risk score was constructed based on the proportional contribution of independent predictors in the multivariable model.

RESULTS: Size (.10 mm), aneurysm rupture, stent assistance, and posttreatment degree of aneurysm occlusion were independently associated with retreatment, whereas intraluminal thrombosis and flow diversion demonstrated a trend toward retreatment. The Aneurysm Recanalization Stratification Scale was constructed by assigning the following weights to statistically and clinically significant predictors: aneurysm-specific factors: size (.10 mm), 2 points; rupture, 2 points; presence of thrombus, 2 points. Treatment-related factors were stent assistance, 21 point; flow diversion, 22 points; Raymond Roy occlusion class 2, 1 point; Raymond Roy occlusion class 3, 2 points. This scale demonstrated good discrimination with a C-statistic of 0.799.

CONCLUSION: Surgical decision making and patient-centered informed consent require comprehensive and accessible information on treatment efficacy. We constructed the Aneurysm Recanalization Stratification Scale to enhance this decisionmaking process. This is the first comprehensive model that has been developed to quantitatively predict the risk of retreatment after endovascular therapy.

Posted on

Current surgical results with low-grade brain arteriovenous malformations

Low-grade brain arteriovenous malformations

J Neurosurg 122:912–920, 2015

Resection is an appealing therapy for brain arteriovenous malformations (AVMs) because of its high cure rate, low complication rate, and immediacy, and has become the first-line therapy for many AVMs. To clarify safety, efficacy, and outcomes associated with AVM resection in the aftermath of A Randomized Trial of Unruptured Brain AVMs (ARUBA), the authors reviewed their experience with low-grade AVMs—the most favorable AVMs for surgery and the ones most likely to have been selected for treatment outside of ARUBA’s randomization process.

Methods A prospective AVM registry was searched to identify patients with Spetzler-Martin Grade I and II AVMs treated using resection during a 16-year period.

Results Of the 232 surgical patients included, 120 (52%) presented with hemorrhage, 33% had Spetzler-Martin Grade I, and 67% had Grade II AVMs. Overall, 99 patients (43%) underwent preoperative embolization, with unruptured AVMs embolized more often than ruptured AVMs. AVM resection was accomplished in all patients and confirmed angiographically in 218 patients (94%). There were no deaths among patients with unruptured AVMs. Good outcomes (modified Rankin Scale [mRS] score 0–1) were found in 78% of patients, with 97% improved or unchanged from their preoperative mRS scores. Patients with unruptured AVMs had better functional outcomes (91% good outcome vs 65% in the ruptured group, p = 0.0008), while relative outcomes were equivalent (98% improved/unchanged in patients with ruptured AVMs vs 96% in patients with unruptured AVMs).

Conclusions Surgery should be regarded as the “gold standard” therapy for the majority of low-grade AVMs, utilizing conservative embolization as a preoperative adjunct. High surgical cure rates and excellent functional outcomes in patients with both ruptured and unruptured AVMs support a dominant surgical posture for low-grade AVMS, with radiosurgery reserved for risky AVMs in deep, inaccessible, and highly eloquent locations. Despite the technological advances in endovascular and radiosurgical therapy, surgery still offers the best cure rate, lowest risk profile, and greatest protection against hemorrhage for low-grade AVMs. ARUBA results are influenced by a low randomization rate, bias toward nonsurgical therapies, a shortage of surgical expertise, a lower rate of complete AVM obliteration, a higher rate of delayed hemorrhage, and short study duration. Another randomized trial is needed to reestablish the role of surgery in unruptured AVM management.

Posted on

Endoscopic endonasal resection of skull base chondrosarcomas

Endoscopic endonasal resection of skull base chondrosarcomas- technique and early results

J Neurosurg 122:735–742, 2015

The authors of this study sought to report the technique and early clinical outcomes of a purely endonasal endoscopic approach for resection of petroclival chondrosarcomas.

Methods Between 2010 and 2014, 8 patients (4 men and 4 women) underwent endonasal endoscopic operations to resect petroclival chondrosarcomas at 2 institutions. The patients’ mean age was 44.8 years (range 30–64 years). One of the patients had previously undergone radiation therapy and another a staged craniotomy. Using volumetric software, an independent neuroradiologist assessed the extent of the resections on MRI scans taken immediately after surgery and at the 3-month follow-up. Immediate complications and control of symptoms were also recorded. In addition, the authors reviewed the current literature on surgical treatment of chondrosarcoma.

Results The mean preoperative tumor diameter and volume were 3.4 cm and 9.8 cm3, respectively. Six patients presented with cranial neuropathies. Endonasal endoscopic surgery achieved > 95% resection in 5 of the 8 patients and < 95% resection in the remaining 3 patients. One of the 6 neuropathies resolved, and the remaining 5 partially improved. One instance of postoperative CSF leakage required a reoperation for repair; no other complications associated with these operations were observed. All of the patients underwent adjuvant radiotherapy.

Conclusions According to the authors’ experience, the endoscopic endonasal route is a safe and effective approach for the resection of appropriately selected petroclival chondrosarcomas.

Posted on

Sacroplasty for Cancer-Associated Insufficiency Fractures

Sacroplasty for Cancer-Associated Insufficiency Fractures

Neurosurgery 76:446–450, 2015

Tumor-associated sacral insufficiency fractures (SIF) present a significant clinical challenge. As survival increases for many malignancies, sacral fractures associated with metastases, sacral or extended pelvic radiation, and paraneoplastic osteoporosis are increasingly common and yet remain difficult to treat in the setting of the potentially significant morbidity of open sacral surgery.

OBJECTIVE: To describe our prospective experience with sacroplasty for tumor-associated lesions, including the largest series to date of radiation-induced SIF.

METHODS: Twenty-five patients with symptomatic SIF underwent 31 percutaneous fluoroscopy-guided sacroplasties with a median 5.8 mL of polymethyl methacrylate or a ceramic-resin composite under fluoroscopic guidance and with concurrent biopsy acquisition. Eighteen patients had fractures related to previous sacral or pelvic radiation; 4 had viable lytic lesions; and 2 had oncology-related osteoporosis. Postoperative pain reduction, procedural morbidity, and functional outcomes were recorded.

RESULTS: Twenty of 25 patients (80%) had reduction in their visual analog pain score at a median follow-up of 6.5 months; no patients worsened. The mean visual analog scale score decreased from 8.8 to 4.7 postprocedurally (P < .001), with significant reductions regardless of the underlying pathology (P < .001 to P < .05). Six of 13 patients with pretreatment ambulatory impairment required fewer ambulatory aids and 3 were newly ambulatory. Extravertebral cement migration was noted in 18 procedures; however, no instance was clinically relevant. Six repeat or contralateral procedures were performed. No morbidity was encountered.

CONCLUSION: Sacroplasty is a safe and effective option for the palliation of sacral fractures in the oncologic population.

Posted on

Invasion of the cavernous sinus space in pituitary adenomas: endoscopic verification and its correlation with an MRI-based classification

Invasion of the cavernous sinus space in pituitary adenomas- endoscopic verification and its correlation with an MRI-based classification

J Neurosurg 122:803–811, 2015

An important prognostic factor for the surgical outcome and recurrence of a pituitary adenoma is its invasiveness into parasellar tissue, particularly into the space of the cavernous sinus (CS). The aims of this study were to reevaluate the existing parasellar classifications using an endoscopic technique and to evaluate the clinical and radiological outcomes associated with each grade.

Methods The authors investigated 137 pituitary macroadenomas classified radiologically at least on one side as Grade 1 or higher (parasellar extension) and correlated the surgical findings using an endoscopic technique, with special reference to the invasiveness of the tumor into the CS. In each case, postoperative MRI was performed to evaluate the gross-total resection (GTR) rate and the rate of endocrinological remission (ER) in functioning adenomas.

Results The authors found a 16% rate of CS invasion during surgery for these macroadenomas. Adenomas radiologically classified as Grade 1 were found to be invasive in 1.5%, and the GTR/ER rate was 83%/88%. For Grade 2 adenomas, the rate of invasion was 9.9%, and the GTR/ER rate was 71%/60%. For Grade 3 adenomas, the rate of invasion was 37.9%, and the GTR/ER rate was 75%/33%. When the superior compartment of the CS (Grade 3A) was involved, the authors found a rate of invasion that was lower (p < 0.001) than that when the inferior compartment was involved (Grade 3B). The rate of invasion in Grade 3A adenomas was 26.5% with a GTR/ER rate of 85%/67%, whereas for Grade 3B adenomas, the rate of surgically observed invasion was 70.6% with a GTR/ER rate of 64%/0%. All of the Grade 4 adenomas were invasive, and the GTR/ER rate was 0%. A comparison of microscopic and endoscopic techniques revealed no difference in adenomas with Grade 1 or 4 parasellar extension. In Grade 2 adenomas, however, the CS was found by the endoscopic technique to be invaded in 9.9% and by microscopic evaluation to be invaded in 88% (p < 0.001); in Grade 3 adenomas, the difference was 37.9% versus 86%, respectively (p = 0.002). Grade 4 adenomas had a statistically significant lower rate of GTR than those of all the other grades. In case of ER only, Grade 1 adenomas had a statistically significant higher rate of remission than did Grade 3B and Grade 4 adenomas.

Conclusions The proposed classification proved that with increasing grades, the likelihood of surgically observed invasion rises and the chance of GTR and ER decreases. The direct endoscopic view confirmed the low rate of invasion of Grade 1 adenomas but showed significantly lower rates of invasion in Grade 2 and 3 adenomas than those previously found using the microscopic technique. In cases in which the intracavernous internal carotid artery was encased (Grade 4), all the adenomas were invasive and the GTR/ER rate was 0%/0%. The authors suggest the addition of Grades 3A and 3B to distinguish the strikingly different outcomes of adenomas invading the superior CS compartments and those invading the inferior CS compartments.

Posted on

Telo-velar approach to fourth-ventricle tumours: how I do it

Telo-velar approach to fourth-ventricle tumours_how I do it

Acta Neurochir (2015) 157:607–610

The “telo-velar” approach is an alternative to cerebellar splitting to gain access to the fourth ventricle through the so-called cerebello-medullary fissure (CMF).

Method In this approach, the CMF is exposed and access to the ventricle is obtained by incising the tela choroidea and inferior medullary velum. This approach enables the exploration of the entire ventricle cavity from the obex to the aqueduct.

Conclusions The exposure of the fourth ventricle is satisfactory and the floor of the fourth ventricle can be visualised early and protected. The extent of resection and outcome are satisfactory in most patients, including those with large tumours or lesions attached to the lateral or superolateral recesses of the ventricle. The deep rostral tumour attachment is the main limitation of the telo-velar approach

Key Points

• Early exposure of the interface lesion-floor of the fourth ventricle favours a safer tumour dissection.

• We feel that resection of tonsils is not necessary in the surgical setting.

• The posterior arch of C1 should be removed only if the tonsils are below the level of the foramen magnum.

• The improved access to the lateral recess of the ventricle makes the telo-velar approach particularly effective in lesions attached to cerebellar peduncles.

• The wide dissection of the cerebello-medullary fissure and gentle tonsils retraction may prevent from the occurrence of cerebellar mutism or other major cerebellar dysfunctions.

• Even the bilateral opening of the CMF does not result in cerebellar mutism if wide and cautious dissection, avoiding retraction and vascular injuries, is obtained.

• The exposure of the fourth ventricle was satisfactory also in patients harbouring lesions attached to the lateral or even the superolateral recesses of the ventricle.

• A deep rostral tumour attachment seems to be, at least in our experience, the main specific limitation of the telo-velar approach.

• The risk of hydrocephalus can be reduced by opening of the fissure bilaterally, exposing the aqueduct, and by cisterna magna-fourth ventricle communication augmentation.

• The EVD is taken in place for 48-72 h to prevent possible abrupt increase of the intracranial pressure and to favour wound closure.

Posted on

Endoscopy-Assisted Interhemispheric Transcallosal Hemispherotomy

Endoscopy-Assisted Interhemispheric Transcallosal Hemispherotomy

Neurosurgery 76:485–495, 2015

Various hemispherotomy techniques have been developed to reduce complication rates and achieve the best possible seizure control.

OBJECTIVE: To present a novel and minimally invasive endoscopy-assisted approach to perform this procedure.

METHODS: Endoscopy-assisted interhemispheric transcallosal hemispherotomy was performed in 5 children (April 2013-June 2014). The procedure consisted of performing a small craniotomy (4 · 3 cm) just lateral to midline using a transverse skin incision. After dural opening, the surgery was performed with the assistance of a rigid high-definition endoscope, and bayoneted self-irrigating bipolar forceps and other standard endoscopic instruments. Steps included a complete corpus callosotomy followed by the disconnection of the hemisphere at the level of the basal nuclei and thalamus. The surgeries were performed in a dedicated operating room with intraoperative magnetic resonance imaging and neuronavigation. Intraoperative magnetic resonance imaging confirmed a total disconnection.

RESULTS: The pathologies for which surgeries were performed included sequelae of middle a cerebral artery infarct (n = 2), Rasmussen syndrome (n = 1), and hemimegalencephaly (2). Four patients had an Engel class I and 1 patient had a class II outcome at a mean follow-up of 10.2 months (range, 3-14 months). The mean blood loss was 80mL, and mean operating time was 220 minutes. There were no complications in this study.

CONCLUSION: This study describes a pilot novel technique and the feasibility of performing a minimally invasive, endoscopy-assisted hemispherotomy.

Posted on

Frontal operculum gliomas: language outcome following resection

Frontal operculum gliomas- language outcome following resection

J Neurosurg 122:725–734, 2015

The dominant hemisphere frontal operculum may contain critical speech and language pathways, and due to these properties, patients with tumors of the opercular region may be at higher risk for postoperative speech dysfunction. However, the likelihood of incurring temporary or permanent language dysfunction is unknown.

Methods The authors retrospectively analyzed their cohort of patients with frontal gliomas to identify those tumors that predominantly involved the dominant frontal operculum. Each tumor was classified as involving the pars orbitalis, pars triangularis, pars opercularis, or a combination of some or all of these areas. The authors then identified and compared characteristics between those patients experiencing transient or permanent speech deficits, as opposed to those with no language dysfunction.

Results Forty-three patients were identified for inclusion in this analysis. Transient deficits occurred in 12 patients (27.9%), while 4 patients (9.8%) had persistent deficits involving language. Individuals with preoperative language deficits and patients with seizures characterized by speech dysfunction appear to be at the highest risk to develop a deficit (relative risks 3.09 and 1.75, respectively). No patient with a tumor involving the pars orbitalis experienced a persistent deficit.

Conclusions Resection of gliomas is widely recognized as a critical element of improved outcome. Given the low rate of language morbidity reported in this group of patients, resection of gliomas within the dominant frontal operculum is well-tolerated with acceptable morbidity and, in this particular location, should not be a deterrent in the overall management of these tumors.

Posted on

Fully endoscopic retrosigmoid approach for posterior petrous meningioma and trigeminal microvascular decompression

Fully endoscopic retrosigmoid approach for posterior petrous

Acta Neurochir (2015) 157:611–615

Cerebellopontine angle tumor resection and cranial nerve microvascular decompression are usually performed with the aid of the surgical microscope. The endoscope is commonly used as an adjuvant.

Method A retrosigmoid craniectomy is done. Upon dural opening, the endoscope is inserted into the operative field along the petrotentorial junction. Cerebrospinal fluid drainage provides a wider space for introduction of the endoscope and surgical instruments. Traditional microsurgical techniques are used during the entire procedure.

Conclusion A fully endoscopic retrosigmoid approach is a safe and effective procedure for cerebellopontine angle tumor resection and cranial nerve microvascular decompression.

Key points

• Careful examination of preoperative studies is needed to identify anatomical peculiarities.

• Patient positioning: the head must be gently flexed and its vertex gently tilted toward the floor.

• Neurophysiologic monitoring and intraoperative navigation.

• Craniectomy: partial exposure of the transverse and sigmoid sinuses.

• Curvilinear dural incision reflected laterally to minimize the risk of sinus injury.

• Opening the cerebellomedullary cistern for CSF drainage and cerebellar relaxation.

• Dynamic endoscopy enhances depth perception and must be performed by a team with experience in endoscopic intracranial surgery.

• Traditional microsurgical techniques have to be applied during the entire operation.

• Multilayer reconstruction, including watertight dural closure.

• Meningiomas causing brainstem shift are not suitable for endoscopic resection.

Posted on

An Experimental Feasibility Study on Robotic Endonasal Telesurgery

Robotic teleneurosurgery

Neurosurgery 76:479–484, 2015

Novel robots have recently been developed specifically for endonasal surgery. They can deliver several thin, tentacle-like surgical instruments through a single nostril. Among the many potential advantages of such a robotic system is the prospect of telesurgery over long distances.

OBJECTIVE: To describe a phantom pituitary tumor removal done by a surgeon in Nashville, Tennessee, controlling a robot located approximately 800 km away in Chapel Hill, North Carolina, the first remote telesurgery experiment involving tentacle-like concentric tube manipulators.

METHODS: A phantom pituitary tumor removal experiment was conducted twice, once locally and once remotely, with the robotic system. Robot commands and video were transmitted across the Internet. The latency of the system was evaluated quantitatively in both local and remote cases to determine the effect of the 800-km distance between the surgeon and robot.

RESULTS: We measured a control and video latency of ,100 milliseconds in the remote case. Qualitatively, the surgeon was able to carry out the experiment easily and observed no discernable difference between the remote and local cases.

CONCLUSION: Telesurgery over long distances is feasible with this robotic system. In the longer term, this may enable expert skull base surgeons to help many more patients by performing surgeries remotely over long distances.

Posted on

Solitary lesions of the clivus: what else besides chordomas?

Clivus lesions

Solitary non-chordomatous lesions of the clivus are rare pathologies, which represent a diagnostic challenge. This study provides an overview of the clinical, radiological and prognostic characteristics of non-chordomatous clival lesions, highlighting current therapeutic options.

Methods Twenty-two non-chordomatous lesions of the clivus were collected. A retrospective analysis of clinical and radiological patterns as well as survival data was conducted.

Results Clinical presentation was a result of local mass effect. Imaging features, although mainly specific, were not always diagnostic. Extent of surgery was gross total in 45.5 % of cases. Depending on the histology, biological behaviour and presence of seeding, adjuvant treatment was performed, tailoring the treatment strategy to the single patient.

Conclusions Solitary non-chordomatous lesions of the clival bone are more prevalent than expected. They should be approached with a correct differential diagnosis, considering specific epidemiological, radiological, and histopathological characteristics, to minimise diagnostic bias and allow the planning of the best treatment strategy.

Posted on

Aneurysm diameter as a risk factor for pretreatment rebleeding: a meta-analysis

MCA aneurysm

J Neurosurg 122:921–928, 2015

Aneurysmal rerupture prior to treatment is a major cause of death and morbidity in aneurysmal subarachnoid hemorrhage. Recognizing risk factors for aneurysmal rebleeding is particularly relevant and might help to identify the aneurysms that benefit from acute treatment. It is uncertain if the size of the aneurysm is related to rebleeding. This meta-analysis was performed to evaluate whether an association could be determined between aneurysm diameter and the rebleeding rate before treatment. Potentially confounding factors such age, aneurysm location, and the presence of hypertension were also evaluated.

Methods The authors systematically searched the PubMed, Embase, and Cochrane databases up to April 3, 2013, for studies of patients with aneurysmal subarachnoid hemorrhage that reported the association between aneurysm diameter and pretreatment aneurysmal rebleeding. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria were used to evaluate study quality.

Results Seven studies, representing 2121 patients, were included in the quantitative analysis. The quality of the studies was low in 2 and very low in 5. Almost all of the studies used 10 mm as the cutoff point for size among other classes, and only one used 7 mm. An analysis was performed with this best unifiable cutoff point. Overall rebleeding occurred in 360 (17.0%) of 2121 patients (incidence range, from study to study, 8.7%–28.4%). The rate of rebleeding in small and large aneurysms was 14.0% and 23.6%, respectively. The meta-analysis of the 7 studies revealed that larger size aneurysms were at a higher risk for rebleeding (OR 2.56 [95% CI 1.62–4.06]; p = 0.00; I2 = 60%). The sensitivity analysis did not alter the results. Five of the 7 studies reported data regarding age; 4 studies provided age-adjusted results and identified a persistent relationship between lesion size and the risk of rebleeding. The presence of hypertension was reported in two studies and was more prevalent in patients with rebleeding in one of these. Location (anterior vs posterior circulation) was reported in 5 studies, while in 4 there was no difference in the rebleeding rate. One study identified a lower risk of rebleeding associated with posterior location aneurysms.

Conclusions This meta-analysis showed that aneurysm size is an important risk factor for aneurysmal rebleeding and should be used in the clinical risk assessment of individual patients. The authors’ results confirmed the current guidelines and underscored the importance of acute treatment for large ruptured aneurysms.

Posted on

Impact of intraoperative magnetic resonance imaging and functional neuronavigation on surgical outcome in patients with gliomas involving language areas

Impact of intraoperative magnetic resonance imaging and functional neuronavigation on surgical outcome in patients with gliomas involving language areas

Neurosurg Rev (2015) 38:319–330

Balancing the benefit of extensive tumor resection with the consequence of potential postoperative language deficits remains a challenge in glioma surgery involving language areas. This study is designed to evaluate the impact of intraoperative magnetic resonance imaging (iMRI) and functional neuronavigation on surgical outcome in patients with gliomas involving language areas.

Two hundred seventeen patients were prospectively enrolled, 124 in the study group underwent iMRI and functional neuronavigationguided microsurgery and 93 in the control group underwent conventional navigation-guided microsurgery. Extent of tumor volume resection (EoR) and rate of gross total resection (rGTR) were calculated perioperatively. Aphasia quotient (AQ) was assessed to evaluate the change of language function perioperatively and at 6-month follow-up. Survival outcome for glioblastoma, including progression-free survival (PFS) and overall survival (OS), were recorded.

In 198 glioma patients (112 in the study group and 86 in the control group), EoR (95.50 versus 89.85 %, p<0.001) and rGTR (69.60 versus 47.70 %, p=0.002) were significantly higher in the study group, and language functions were also better at 6-month follow-up in the study group (87.47 versus 78.73, p=0.001). Furthermore, postoperative new aphasia occurred in 34.8 % of the control group, whereas it occurred only in 2.3 % of the study group (p<0.001). In addition, PFS (12.5 versus 6.6 m, p=0.003) and OS (19.6 versus 13.0 m, p<0.001) for patients with glioblastomas were dramatically prolonged in the study group than in the control group.

These results indicated that iMRI and functional neuronavigation may help maximize tumor resection, minimize language deficits in patients with gliomas involving language areas, and improve survival time for patients with glioblastomas.

Posted on

Impact of Body Mass Index on Adjacent Segment Disease After Lumbar Fusion for Degenerative Spine Disease

Impact of Body Mass Index on Adjacent Segment Disease After Lumbar Fusion for Degenerative Spine Disease

Neurosurgery 76:396–402, 2015

Adjacent segment disease is an important complication after fusion of degenerative lumbar spines. However, the role of body mass index (BMI) in adjacent segment disease has been addressed less.

OBJECTIVE: To examine the relationship between BMI and adjacent segment disease after lumbar fusion for degenerative spine diseases.

METHODS: For this retrospective study, we enrolled 190 patients undergoing lumbar fusion surgery for degeneration. BMI at admission was documented. Adjacent segment disease was defined by integration of the clinical presentations and radiographic criteria based on the morphology of the dural sac on magnetic resonance images.

RESULTS: Adjacent segment disease was identified in 13 of the 190 patients, accounting for 6.8%. The interval between surgery and diagnosis as adjacent segment disease ranged from 21 to 66 months. Five of the 13 patients required subsequent surgical intervention for clinically relevant adjacent segment disease. In the logistic regression model, BMI was a risk factor for adjacent segment disease after lumbar fusion for degenerative spine diseases (odds ratio, 1.68; 95% confidence interval, 1.27- 2.21; P < .001). Any increase of 1 mean value in BMI would increase the adjacent segment disease rate by 67.6%. The patients were subdivided into 2 groups based on BMI, and up to 11.9% of patients with BMI ≥25 kg/m2 were diagnosed as having adjacent segment disease at the last follow-up.

CONCLUSION: BMI is a risk factor for adjacent segment disease in patients undergoing lumbar fusion for degenerative spine diseases. Because BMI is clinically objective and modifiable, controlling body weight before or after surgery may provide opportunities to reduce the rate of adjacent segment disease and to improve the outcome of fusion surgery.

Posted on

Surgical results of tumor resection using tractography-integrated navigation-guided fence-post catheter techniques and motor-evoked potentials for preservation of motor function in patients with glioblastomas near the pyramidal tracts

Surgical results of tumor resection using tractography-integrated

Neurosurg Rev (2015) 38:293–307

The current optimal surgery for glioblastomas (GBMs) near the pyramidal tract (PT) is to remove as much tumor as possible and to preserve motor function. The purpose of this study is to investigate the usefulness of tractography integrated navigation-guided fence-post catheter techniques and motor-evoked potentials (MEPs) for preserving postoperative motor function after GBM surgery.

We retrospectively examined 49 patients who underwent resection for GBM near the PT. Diffusion tensor (DT) imaging-based tractography of the PT was performed preoperatively and integrated into the navigation system. When possible, silicon catheters were used as “fence-posts” and were inserted along the tumor boundaries, avoiding the PT, before tumor removal using the navigation system (fence-post catheter techniques). Cortical and subcortical MEPs were also monitored during resection of the tumor. Fence-post catheter techniques using a tractography integrated navigation system were used in 45 of 49 patients.

This technique enabled placement of the catheters, avoided the motor pathways, and allowed easier resection of the tumors. Tumors near the PT were resected using subcortical and cortical MEPs. The amplitudes of cortical MEPs after tumor removal were maintained at over 33 % of those obtained before resection.

Thirty-six patients showed obvious responses of subcortical MEPs at ≤20 mA. The degree of resection was gross total in 21 patients, subtotal in 21, and partial in seven. One month after surgery, only one patient showed worsened motor function.

Therefore, fence-post catheter techniques using a tractography-integrated navigation system and MEPs may contribute to preserving motor function after surgery for GBMs that are near the PT.

Proudly powered by WordPress