Posts

Posted on

Deep brain stimulation for aggressiveness: long-term follow-up and tractography study of the stimulated brain areas

J Neurosurg 134:366–375, 2021

Initial studies applying deep brain stimulation (DBS) of the posteromedial hypothalamus (PMH) to patients with pathological aggressiveness have yielded encouraging results. However, the anatomical structures involved in its therapeutic effect have not been precisely identified. The authors’ objective was to describe the long-term outcome in their 7-patient series, and the tractography analysis of the volumes of tissue activated in 2 of the responders.

METHODS This was a retrospective study of 7 subjects with pathological aggressiveness. The findings on MRI with diffusion tensor imaging (DTI) in 2 of the responders were analyzed. The authors generated volumes of tissue activated according to the parameters used, and selected those volumes as regions of interest to delineate the tracts affected by stimulation.

RESULTS The series consisted of 5 men and 2 women. Of the 7 patients, 5 significantly improved with stimulation. The PMH, ventral tegmental area, dorsal longitudinal fasciculus, and medial forebrain bundle seem to be involved in the stimulation field.

CONCLUSIONS In this series, 5 of 7 medication-resistant patients with severe aggressiveness who were treated with bilateral PMH DBS showed a significant long-lasting improvement. The PMH, ventral tegmental area, dorsal longitudinal fasciculus, and medial forebrain bundle seem to be in the stimulation field and might be responsible for the therapeutic effect of DBS.

 

Posted on

A cadaveric precision and accuracy analysis of augmented reality–mediated percutaneous pedicle implant insertion

J Neurosurg Spine 34:316–324, 2021

Augmented reality–mediated spine surgery (ARMSS) is a minimally invasive novel technology that has the potential to increase the efficiency, accuracy, and safety of conventional percutaneous pedicle screw insertion methods. Visual 3D spinal anatomical and 2D navigation images are directly projected onto the operator’s retina and superimposed over the surgical field, eliminating field of vision and attention shift to a remote display. The objective of this cadaveric study was to assess the accuracy and precision of percutaneous ARMSS pedicle implant insertion.

METHODS Instrumentation was placed in 5 cadaveric torsos via ARMSS with the xvision augmented reality headmounted display (AR-HMD) platform at levels ranging from T5 to S1 for a total of 113 total implants (93 pedicle screws and 20 Jamshidi needles). Postprocedural CT scans were graded by two independent neuroradiologists using the Gertzbein- Robbins scale (grades A–E) for clinical accuracy. Technical precision was calculated using superimposition analysis employing the Medical Image Interaction Toolkit to yield angular trajectory (°) and linear screw tip (mm) deviation from the virtual pedicle screw position compared with the actual pedicle screw position on postprocedural CT imaging.

RESULTS The overall implant insertion clinical accuracy achieved was 99.1%. Lumbosacral and thoracic clinical accuracies were 100% and 98.2%, respectively. Specifically, among all implants inserted, 112 were noted to be Gertzbein- Robbins grade A or B (99.12%), with only 1 medial Gertzbein-Robbins grade C breach (> 2-mm pedicle breach) in a thoracic pedicle at T9. Precision analysis of the inserted pedicle screws yielded a mean screw tip linear deviation of 1.98 mm (99% CI 1.74–2.22 mm) and a mean angular error of 1.29° (99% CI 1.11°–1.46°) from the projected trajectory. These data compare favorably with data from existing navigation platforms and regulatory precision requirements mandating that linear and angular deviation be less than 3 mm (p < 0.01) and 3° (p < 0.01), respectively.

CONCLUSIONS Percutaneous ARMSS pedicle implant insertion is a technically feasible, accurate, and highly precise method.

 

Posted on

The Role of Prophylactic Intraventricular Antibiotics in Reducing the Incidence of Infection and Revision Surgery in Pediatric Patients Undergoing Shunt Placement

Neurosurgery 88(2)2021: 301–305

Ventriculoperitoneal shunt placement remains the primary treatment modality for children with hydrocephalus. However, morbidity and revision surgery secondary to infection remains high, even while using antibiotic-impregnated shunts.

OBJECTIVE: To determine whether intraoperative injection of antibiotics is independently associated with reduced rates of infection and revision surgery in children undergoing shunt placement.

METHODS: This is an analysis of a prospectively collected, multicenter, shunt-specific neurosurgical registry consisting of data from over 100 hospitals collected between 2016 and 2017. All patients under 18 yr of age undergoing first-time shunt placement for the definitive treatment of hydrocephaluswere included. The primary exposure of interest was injection of intraventricular antibiotics into the shunt catheter following shunt placement and prior to closure. The use of additional surgical adjuncts, such as antibiotic-impregnated shunts, stereotactic guidance, and endoscopy was collected. The primary outcome metric was the need for additional intervention because of an infection.

RESULTS: A total of 2007 pediatric patients undergoing shunt placement for hydrocephalus were identified. Postoperatively, 97 (4.8%) patients had additional intervention secondary to infection. In a multivariable regression model controlling for patient characteristics, etiology of hydrocephalus, prior temporizing measures, and placement of an antibiotic-impregnated shunt, injection of intraventricular antibiotics was associated with a significant reduction in postoperative infections (odds ratio = 0.29, 95% CI: 0.04-0.89, P=.038). Of those receiving intraventricular antibiotics, only 2 (0.38%)went on to undergo re-intervention due to infection.

CONCLUSION: These data suggest that for this select group of patients, use of intraventricular antibiotics was associated with decreased rates of re-intervention secondary to infection.

Posted on

Predicting the Extent of Resection in Low-Grade Glioma by Using Intratumoral Tractography to Detect Eloquent FasciclesWithin the Tumor

Neurosurgery 88(2) 2021: E190–E202

An early maximal safe surgical resection is the current treatment paradigm for low-grade glioma (LGG). Nevertheless, there are no reliable methods to accurately predict the axonal intratumoral eloquent areas and, consequently, to predict the extent of resection.

OBJECTIVE: To describe the functional predictive value of eloquent white matter tracts within the tumor by using a pre- and postoperative intratumoral diffusion tensor imaging (DTI) tractography protocol in patients with LGG.

METHODS: A preoperative intratumoral DTI-based tractography protocol, using the tumor segmented volume as the only seed region, was used to assess the tracts within the tumor boundaries in 22 consecutive patients with LGG. The reconstructed tracts were correlated with intraoperative electrical stimulation (IES)-based language and motor subcortical mapping findings and the extent of resection was assessed by tumor volumetrics.

RESULTS: Identification of intratumoral language and motor tracts significantly predicted eloquent areas within the tumor during the IES mapping: the positive predictive value for the pyramidal tract, the inferior fronto-occipital fasciculus, the arcuate fasciculus and the inferior longitudinal fasciculus positive was 100%, 100%, 33%, and 80%, respectively, whereas negative predictive value was 100% for all of them. The reconstruction of at least one of these tracts within the tumor was significantly associated with a lower extent of resection (67%) as opposed to the extent of resection in the cases with a negative intratumoral tractography (100%) (P< .0001).

CONCLUSION: Intratumoral DTI-based tractography is a simple and reliable method, useful in assessing glioma resectability based on the analysis of intratumoral eloquent areas associated with motor and language tracts within the tumor.

Posted on

Prepontine Shunting for Pseudotumor Cerebri in Previously Failed Shunt Patients

Neurosurgery 88(2)2021: 306–312

Shunting procedures have a high failure rate when used to treat pseudotumor cerebri (PTC) patients who have failed medical therapy. This failure is believed to be attributable to the collapsibility of the ventricular systemwhenexposed to increased differential pressure gradients in the cerebral spinal fluid compartments caused by ventriculoperitoneal shunts (VPS).

OBJECTIVE: To investigate whether prepontine/interpeduncular cistern shunting may be a reasonable alternative to VPS intervention in PTC patients with history of shunt failure. There have been no large series of cisternal-peritoneal shunt (CPS) patients in the PTC population.

METHODS: A retrospective review of 49 patients with placement of CPS for PTC with 2 failed prior shunting procedures was performed. Shunt survivability was based on shunt patency and resolution of ophthalmologic symptoms and cranial nerve deficits. All patientswere followed for aminimum of 3 yrwith serial ophthalmologic and neurosurgical evaluations.

RESULTS: At 3 yr, 44 of the 49 (88.9%) patients had working CPS. Three patients in this group had infections requiring complete shunt removal. Excluding infections, 44 of 46 (95.5%) shunts were functional at 3 yr. There were 3 small, asymptomatic hemorrhages that did not increase patient length of stay, and there were no catastrophic hemorrhages or strokes. There were also no abdominal complications related to shunt placement.

CONCLUSION: CPS is a viable alternative to VPS in PTC patients who have failed traditional shunting methods to give these patients a persistent benefit of a working shunt. The procedure provides this solution with low operative and perioperative morbidity.

Posted on

The ipsilateral interhemispheric transprecuneal approach: microsurgical anatomy, indications, and neurosurgical applications

Neurosurgical Review (2021) 44:529–541

Surgical treatment of intraventricular lesions is challenging because of their deep location, vascularization, and their complex relationships with white matter fibers. The authors undertook this study to describe the microsurgical anatomy of the white matter fibers covering the lateral wall of the atrium and temporal horn and to demonstrate how the ipsilateral interhemispheric transprecuneal approach can be safely used to remove lesions of this region sparing the anatomo-functional integrity of the fibers themselves. A detailed description of the approach including operative measurements is also given.

The Klingler’ technique with progressive identification of white matter fibers covering the lateral wall of the atrium and temporal horn was performed on ten formalin-fixed human hemispheres. Then, ten fresh, non-formalin-fixed non-silicon-injected adult cadaveric heads were analyzed for the simulation of the ipsilateral interhemispheric transprecuneal approach. Three illustrative cases are presented. The simulation of the interhemispheric transprecuneal approach on ten fresh non-formalin-fixed specimens showed that a 10 to 20 mm corticotomy perpendicular to the parieto-occipital sulcus at the junction with the cingulum allows a wide corridor for the exposure of the entire atrial cavity and the posterior third of the temporal horn.

The ipsilateral interhemispheric transprecuneus approach represents a safe and effective option for tumors involving the atrium and the posterior third of the temporal horn.

Posted on

A Retrospective Analysis in 1347 Patients Undergoing Cement Augmentation for Osteoporotic Vertebral Compression Fracture: Is the Sandwich Vertebra at a Higher Risk of Further Fracture?

Neurosurgery 88(2) 2021: 342–348

Multiple percutaneous vertebral cement augmentation may create sandwich vertebrae. Whether the sandwich vertebra is at higher risk of further fracture remains unknown.

OBJECTIVE: To compare the incidence of further fractures of sandwich vertebrae and adjacent vertebrae and to identify potential risk factors for sandwich vertebral fractures.

METHODS: Patients who underwent cement augmentation for osteoporotic vertebral compression fractures (OVCFs) in a single medical center between January 2012 and December 2015 were included. A sandwich vertebra was defined as an intact vertebra located between 2 previously cemented vertebrae. Demographic data and imaging findings were recorded. All patients were followed up for at least 24 mo postoperatively. During follow-up period, if the patient reported new-onset back pain with corresponding imaging findings, a diagnosis of sandwich vertebral fracture was made.

RESULTS: Among the 1347 patients who underwent vertebroplasty/kyphoplasty for OVCFs, 127 patients with 128 fracture levels met the criteria for sandwich vertebrae (females/males 100/27,mean age 77.8±7.7 yr old). The fracture locationwas most common in the thoraco-lumbar junction (T10-L2), 68.5% (87/127). The incidence of sandwich vertebral fracturewas 21.3%,whereas the incidence of adjacent level fracture of those with no sandwich vertebra was 16.4% (196/1194), P= .1879.

CONCLUSION: The incidence of sandwich vertebral fracture is not higher than that at the adjacent levels. The factor associated with further sandwich vertebral fracture was male gender. Once sandwich vertebral fracture occurred, patients may seek more surgical intervention than those with only adjacent fractures.

Posted on

Access to Meckel’s cave for biopsies of indeterminate lesions

Neurosurgical Review (2021) 44:249–259

Accessing Meckel’s cave (MC) is surgically challenging. Open approaches are complex and often correlated with high morbidity. Endoscopic approaches emerged in the last decade as feasible alternatives to open approaches, especially for sampling indeterminate lesions.

This article first analyses available routes to approach Meckel’s cave and presents furthermore an illustrative case. We conducted a systematic review and reported according to the guidelines for preferred reporting items for systematic reviews and meta-analyses (PRISMA). Various surgical approaches identified through the search are evaluated and discussed in detail. Additionally, we report on a case of woman with a lesion in MC, which was accessed through an endoscopic transpterygoid approach subsequently diagnosed as a diffuse large B cell lymphoma. Our search delivered 75 articles that included case reports (n = 21), cadaveric studies (n = 32), clinical articles (n = 16), review of the literatures (n = 3), as well as technical notes (n = 2) and a radiological manuscript (n = 1).

Open routes included lateral approaches with many variations, mainly intra- and extradural pterional approaches and anterior petrosal, as well as a retrosigmoid intradural suprameatal and a lateral transorbital approach.

Endoscopically, MC was reached via approaches that included transpterygoid, transorbital or infraorbital fissure routes.

Percutaneous approaches, e.g. through the foramen ovale, were also described. Multiple surgical approaches to MC are currently available.

Their different characteristics as well as individual patient factors, such as clinical history and the localization of the disease, have to be considered when choosing a surgical corridor.

Studies included in this review highlight the endonasal endoscopic transpterygoidal technique as an excellent corridor for biopsies in the ventral MC.

Posted on

Stereotactic radiosurgery as the first-line treatment for intracanalicular vestibular schwannomas

J Neurosurg February 5, 2021: 1-7

This report evaluates the outcomes of stereotactic radiosurgery (SRS) as the first-line treatment of intracanalicular vestibular schwannomas (VSs).

METHODS Between 1987 and 2017, the authors identified 209 patients who underwent SRS as the primary intervention for a unilateral intracanalicular VS. The median patient age was 54 years (range 22–85 years); 94 patients were male and 115 were female. Three patients had facial neuropathy at the time of SRS. One hundred fifty-five patients (74%) had serviceable hearing (Gardner-Robertson [GR] grades I and II) at the time of SRS. The median tumor volume was 0.17 cm3 (range 0.015–0.63 cm3). The median margin dose was 12.5 Gy (range 11.0–25.0 Gy). The median maximum dose was 24.0 Gy (range 15.7–50.0 Gy).

RESULTS The progression-free survival rates of all patients with intracanalicular VS were 97.5% at 3 years, 95.6% at 5 years, and 92.1% at 10 years. The rates of freedom from the need for any additional intervention were 99.4% at 3 years, 98.3% at 5 years, and 98.3% at 10 years. The serviceable hearing preservation rates in GR grade I and II patients at the time of SRS were 76.6% at 3 years, 63.5% at 5 years, and 27.3% at 10 years. In univariate analysis, younger age (< 55 years, p = 0.011), better initial hearing (GR grade I, p < 0.001), and smaller tumor volumes (< 0.14 cm3, p = 0.016) were significantly associated with improved hearing preservation. In multivariate analysis, better hearing (GR grade I, p = 0.001, HR 2.869, 95% CI 1.569–5.248) and smaller tumor volumes (< 0.14 cm3, p = 0.033, HR 2.071, 95% CI 1.059–4.047) at the time of SRS were significantly associated with improved hearing preservation. The hearing preservation rates of patients with GR grade I VS were 88.1% at 3 years, 77.9% at 5 years, and 38.1% at 10 years. The hearing preservation rates of patients with VSs smaller than 0.14 cm3 were 85.5% at 3 years, 77.7% at 5 years, and 42.6% at 10 years. Facial neuropathy developed in 1.4% from 6 to 156 months after SRS.

CONCLUSIONS SRS provided sustained tumor control in more than 90% of patients with intracanalicular VS at 10 years and freedom from the need for additional intervention in more than 98% at 10 years. Patients with initially better hearing and smaller VSs had enhanced serviceable hearing preservation during an observation interval up to 10 years after SRS.

Posted on

Revision and complication rates in adult shunt surgery

Acta Neurochirurgica (2021) 163:447–454

CSF diversion with shunt placement is frequently associated with need for later revisions as well as surgical complications. We sought to review revision and complication rates following ventriculoperitoneal, ventriculoatrial and cystoperitoneal shunt placement in adult patients, and to identify potential risk factors for revision surgery and postoperative complications.

Method Included patients were adults (≥ 18 years) who underwent primary shunt insertion at St. Olavs Hospital in Trondheim, Norway, from 2008 through 2017. The electronic medical records and diagnostic imaging from all hospitals in our catchment area were retrospectively reviewed. Follow-up ranged from 1 to 11 years. Complications were graded according to the Landriel Ibañez classification system.

Results Of the 227 patients included, 47 patients (20.7%) required revision surgery during the follow-up. In total, 90 revision surgeries were performed during follow-up. The most common cause for the first revision was infection (5.7%) and for all revisions proximal occlusion (30.0%). A total of 103 patients (45.4%) experienced ≥ 1 complication(s). Mild to moderate complications (grade I and II) were detected in 35.0% of all procedures. Severe or fatal complications (grade III and IV) were observed in 8.2% of all procedures. Urinary tract infections and pneumonia were common postoperatively (13.9% and 7.3%, respectively), and the most common IIb complication was shunt misplacement (proximally or distally). Two out of fourteen deaths within 30 days were directly associated with surgery. We did not find that aetiology/indication, age or gender influenced the occurrence of revision surgery or a grade III or IV complication.

Conclusions Shunt surgery continues to be a challenge both in terms of revision rates and procedure-related complications. However, the prediction of patients at risk remains difficult. A multidimensional focus is probably needed to reduce risks.

Posted on

Practical answers to frequently asked questions for shared decision-making in adult spinal deformity surgery

J Neurosurg Spine 34:218–227, 2021

The shared decision-making (SDM) process provides an opportunity to answer frequently asked questions (FAQs). The authors aimed to present a concise list of answers to FAQs to aid in SDM for adult spinal deformity (ASD) surgery.

METHODS From a prospective, multicenter ASD database, patients enrolled between 2008 and 2016 who underwent fusions of 5 or more levels with a minimum 2-year follow-up were included. All deformity types were included to provide general applicability. The authors compiled a list of FAQs from patients undergoing ASD surgery and used a retrospective analysis to provide answers. All responses are reported as either the means or the proportions reaching the minimal clinically important difference at the 2-year follow-up interval.

RESULTS Of 689 patients with ASD who were eligible for 2-year follow-up, 521 (76%) had health-related quality-of-life scores available at the time of that follow-up. The mean age at the initial surgery was 58.2 years, and 78% of patients were female. The majority (73%) underwent surgery with a posterior-only approach. The mean number of fused levels was 12.2. Revision surgery accounted for 48% of patients. The authors answered 12 FAQs as follows:

1. Will my pain improve? Back and leg pain will both be reduced by approximately 50%.

2. Will my activity level improve? Approximately 65% of patients feel improvement in their activity level.

3. Will I feel better about myself? More than 70% of patients feel improvement in their appearance.

4. Is there a chance I will get worse? 4.1% feel worse at 2 years postoperatively.

5. What is the likelihood I will have a complication? 67.8% will have a major or minor complication, with 47.8% having a major complication.

6. Will I need another surgery? 25.0% will have a reoperation within 2 years.

7. Will I regret having surgery? 6.5% would not choose the same treatment.

8. Will I get a blood transfusion? 73.7% require a blood transfusion.

9. How long will I stay in the hospital? You need to stay 8.1 days on average.

10. Will I have to go to the ICU? 76.0% will have to go to the ICU.

11. Will I be able to return to work? More than 70% will be working at 1 year postoperatively.

12. Will I be taller after surgery? You will be 1.1 cm taller on average.

CONCLUSIONS The above list provides concise, practical answers to FAQs encountered in the SDM process while counseling patients for ASD surgery.

 

Posted on

Stereotactic Radiosurgery With Versus Without Embolization for Brain ArteriovenousMalformations

Neurosurgery 88(2) 2021: 313–321

Prior comparisons of brain arteriovenous malformations (AVMs) treated using stereotactic radiosurgery (SRS) with or without embolization were inherently flawed, due to differences in the pretreatment nidus volumes.

OBJECTIVE: To compare the outcomes of embolization and SRS, vs SRS alone for AVMs using pre-embolization malformation features.

METHODS: We retrospectively reviewed International Radiosurgery Research Foundation AVM databases from 1987 to 2018. Patients were categorized into the embolization and SRS (E + SRS) or SRS alone (SRS-only) cohorts. The 2 cohorts were matched in a 1:1 ratio using propensity scores. Primary outcome was defined as AVM obliteration. Secondary outcomes were post-SRS hemorrhage, all-cause mortality, radiologic and symptomatic radiation-induced changes (RIC), and cyst formation.

RESULTS: The matched cohorts each comprised 101 patients. Crude AVM obliteration rates were similar between the matched E + SRS vs SRS-only cohorts (48.5% vs 54.5%; odds ratio = 0.788, P = .399). Cumulative probabilities of obliteration at 3, 4, 5, and 6 yr were also similar between the E + SRS (33.0%, 46.4%, 56.2%, and 60.8%, respectively) and SRSonly (32.9%, 46.2%, 56.0%, and 60.6%, respectively) cohorts (subhazard ratio (SHR)=1.005, P = .981). Cumulative probabilities of radiologic RIC at 3, 4, 5, and 6 yr were lower in the E + SRS (25.0%, 25.7%, 26.7%, and 26.7%, respectively) vs SRS-only (45.3%, 46.2%, 47.8%, and 47.8%, respectively) cohort (SHR = 0.478, P = .004). Symptomatic and asymptomatic embolization-related complication rates were 8.3% and 18.6%, respectively. Rates of post- SRS hemorrhage, all-cause mortality, symptomatic RIC, and cyst formation were similar between the matched cohorts.

CONCLUSION: This study refutes the prevalent notion that AVM embolization negatively affects the likelihood of obliteration after SRS.

Posted on

Risk factors for developing subdural hematoma: a registry-based study in 1457 patients with shunted idiopathic normal pressure hydrocephalus

J Neurosurg 134:668–677, 2021

Subdural hematomas and hygromas (SDHs) are common complications in idiopathic normal pressure hydrocephalus (iNPH) patients with shunts. In this registry-based study, patients with shunted iNPH were screened nationwide to identify perioperative variables that may increase the risk of SDH.

METHODS The Swedish Hydrocephalus Quality Registry was reviewed for iNPH patients who had undergone shunt surgery in Sweden in 2004–2014. Potential risk factors for SDH were recorded preoperatively and 3 months after surgery. Drug prescriptions were identified from a national pharmacy database. Patients who developed SDHs were compared with those without SDHs.

RESULTS The study population consisted of 1457 patients, 152 (10.4%) of whom developed an SDH. Men developed an SDH more often than women (OR 2.084, 95% CI 1.421–3.058, p < 0.001). Patients on platelet aggregation inhibitors developed an SDH more often than those who were not (OR 1.733, 95% CI 1.236–2.431, p = 0.001). At surgery, shunt opening pressures had been set 5.9 mm H2O lower in the SDH group than in the no-SDH group (109.6 ± 24.1 vs 115.5 ± 25.4 mm H2O, respectively, p = 0.009). Antisiphoning devices (ASDs) were used in 892 patients but did not prevent SDH. Mean opening pressures at surgery and the follow-up were lower with shunts with an ASD, without causing more SDHs. No other differences were seen between the groups.

CONCLUSIONS iNPH patients in this study were diagnosed and operated on in routine practice; thus, the results represent everyday care. Male sex, antiplatelet medication, and a lower opening pressure at surgery were risk factors for SDH. Physical status and comorbidity were not. ASD did not prevent SDH, but a shunt with an ASD allowed a lower opening pressure without causing more SDHs.

Posted on

Mild and Severe Obesity Reduce the Effectiveness of Lumbar Fusions

Neurosurgery 88 (2) 2021: 285–294

Elevated body mass index (BMI) is a well-known risk factor for surgical complications in lumbar surgery. However, its effect on surgical effectiveness independent of surgical complications is unclear.

OBJECTIVE: To determine increasing BMI’s effect on functional outcomes following lumbar fusion surgery, independent of surgical complications.

METHODS:We retrospectively analyzed a prospectively built, patient-reported, quality of life registry representing 75 hospital systems. We evaluated 1- to 3-level elective lumbar fusions. Patients who experienced surgical complicationswere excluded. A stepwisemultivariate regression model assessed factors independently associated with 1-yr Oswestry Disability Index (ODI), preop to 1-yr ODI change, and achievement of minimal clinically important difference (MCID).

RESULTS: A total of 8171 patients met inclusion criteria: 2435 with class I obesity (BMI 30- 35 kg/m2), 1328 with class II (35-40 kg/m2), and 760 with class III (≥40 kg/m2). Increasing BMI was independently associated with worse 12-mo ODI (t = 8.005, P < .001) and decreased likelihood of achieving MCID (odds ratio [OR] = 0.977, P < .001). One year after surgery, mean ODI, ODI change, and percentage achieving MCID worsened with class I, class II, and class III vs nonobese cohorts (P < .001) in stepwise fashion.

CONCLUSION: Increasing BMI is associated with decreased effectiveness of 1- to 3-level elective lumbar fusion, despite absence of surgical complications. BMI ≥ 30 kg/m2 is, therefore, a risk factor for both surgical complication and reduced benefit from lumbar fusion.

Posted on

Surgical anatomy and nuances of the extended endoscopic endonasal transtuberculum sellae approach: pearls and pitfalls for complications avoidance

Acta Neurochirurgica (2021) 163:399–405

Using the expanded endoscopic transtuberculum approach (EETA), the nuances of this technique have rendered a safe, direct, and feasible ventral corridor for the treatment of extending suprasellar pathologies. This study illustrates surgical landmarks and strategies of paramount importance for complications avoidance.

Methods This study presents the surgical anatomy and nuances of EETA, which can be used to remove large pituitary adenomas with suprasellar extension. Special references to cadaveric dissections highlight anatomical landmarks and surgical key points for complications avoidance.

Conclusion The EETA represents a versatile route for the treatment of sellar/suprasellar pathologies. Although, sizeable extrasellar pituitary tumors still pose a threat due to displacement/encasement of surrounding structures, necessitating accurate knowledge of correlative operative anatomy with traditional landmarks. Complete resection of extrasellar components is essential to avoid postoperative apoplexy.

Posted on

Is the Goutallier grade of multifidus fat infiltration associated with adjacent-segment degeneration after lumbar spinal fusion?

J Neurosurg Spine 34:190–195, 2021

The aim of this study was to investigate whether fat infiltration of the lumbar multifidus (LM) muscle affects revision surgery rates for adjacent-segment degeneration (ASD) after L4–5 transforaminal lumbar interbody fusion (TLIF) for degenerative spondylolisthesis.

METHODS A total of 178 patients undergoing single-level L4–5 TLIF for spondylolisthesis (2006 to 2016) were retrospectively analyzed. Inclusion criteria were a minimum 2-year follow-up, preoperative MR images and radiographs, and single-level L4–5 TLIF for degenerative spondylolisthesis. Twenty-three patients underwent revision surgery for ASD during the follow-up. Another 23 patients without ASD were matched with the patients with ASD. Demographic data, Roussouly curvature type, and spinopelvic parameter data were collected. The fat infiltration of the LM muscle (L3, L4, and L5) was evaluated on preoperative MRI using the Goutallier classification system.

RESULTS A total of 46 patients were evaluated. There were no differences in age, sex, BMI, or spinopelvic parameters with regard to patients with and those without ASD (p > 0.05). Fat infiltration of the LM was significantly greater in the patients with ASD than in those without ASD (p = 0.029). Fat infiltration was most significant at L3 in patients with ASD than in patients without ASD (p = 0.017). At L4 and L5, there was an increasing trend of fat infiltration in the patients with ASD than in those without ASD, but the difference was not statistically significant (p = 0.354 for L4 and p = 0.077 for L5).

CONCLUSIONS Fat infiltration of the LM may be associated with ASD after L4–5 TLIF for spondylolisthesis. Fat infiltration at L3 may also be associated with ASD at L3–4 after L4–5 TLIF.

Posted on

Survival, Dependency, and Health-Related Quality of Life in Patients With Ruptured Intracranial Aneurysm

Neurosurgery 88:252–260, 2021

Previous analyses of the International Subarachnoid Aneurysm Trial (ISAT) cohort have reported on clinical outcomes after treatment of a ruptured intracranial aneurysm with either neurosurgical clipping or endovascular coiling.

OBJECTIVE: To evaluate the long-term quality-adjusted life years (QALYs) gained of endovascular coiling compare to neurosurgical clipping in the UK cohort of ISAT.

METHODS: Between September 12, 1994 and May 1, 2002, patients with ruptured intracranial aneurysms who were assumed treatment equipoise were randomly allocated to either neurosurgical clipping or endovascular coiling. We followed-up 1644 patients in 22 UK neurosurgical centers for a minimum of 10 yr. Health-related quality of life (HRQoL) was collected through yearly questionnaires,measured by utilities calculated from the EQ- 5D-3L. We compared HRQoL between the 2 treatment groups over a period of 10 yr. In all, 1-yr, 5-yr, and 10-yr QALYs were estimated by combining utility and survival information.

RESULTS: Higher average utility values were found in the endovascular group throughout the follow-up period, with mean differences between groups statistically significant in most years. The 10-yr QALYs were estimated to be 6.68 (95% CI: 6.45-6.90) in the coiling group and 6.32 (95% CI: 6.10-6.55) in the clipping group, respectively, a significant mean difference of 0.36 (95% CI: 0.04-0.66). A third of this mean QALYs gain was estimated to derive solely from HRQoL differences.

CONCLUSION: HRQoL after treatment of a ruptured intracranial aneurysm was better after endovascular coiling compared to neurosurgical clipping, which contributed significantly to the QALYs gained over a 10-yr period.

Posted on

How I do it: mini invasive transforaminal lumbar interbody fusion

Acta Neurochirurgica (2021) 163:289–293

Minimally invasive approaches for lumbar fusion are aimed at reducing soft tissue injury in order to minimize surgical morbidity and facilitate recovery.

Method Applied to lumbar fusion, such an approach is described as a mini-open transforaminal lumbar interbody fusion (TLIF). Important anatomical landmarks are reviewed. Indications, advantages, and limitations are discussed, and a step-by-step description of the procedure is presented.

Results Decompression, fixation, and bone grafting can be achieved efficiently through this approach with lesser blood loss, shorter hospital stay, reduced rate of general complications, and infections as well as a lower readmission rate.

Conclusion The mini-open TLIF technique, as presented here, is a safe and efficient procedure to achieve lumbar fusion with a reduced rate of complications related to surgery.

Posted on

Corpus callosotomy performed with laser interstitial thermal therapy

J Neurosurg 134:314–322, 2021

Corpus callosotomy is a palliative procedure that is effective at reducing seizure burden in patients with medically refractory epilepsy. The procedure is traditionally performed via open craniotomy with interhemispheric microdissection to divide the corpus callosum. Concerns for morbidity associated with craniotomy can be a deterrent to patients, families, and referring physicians for surgical treatment of epilepsy. Laser interstitial thermal therapy (LITT) is a less invasive procedure that has been widely adopted in neurosurgery for the treatment of tumors. In this study, the authors investigated LITT as a less invasive approach for corpus callosotomy.

METHODS The authors retrospectively reviewed all patients treated for medically refractory epilepsy by corpus callosotomy, either partial or completion, with LITT. Chart records were analyzed to summarize procedural metrics, length of stay, adverse events, seizure outcomes, and time to follow-up. In select cases, resting-state functional MRI was performed to qualitatively support effective functional disconnection of the cerebral hemispheres.

RESULTS Ten patients underwent 11 LITT procedures. Five patients received an anterior two-thirds LITT callosotomy as their first procedure. One patient returned after LITT partial callosotomy for completion of callosotomy by LITT. The median hospital stay was 2 days (IQR 1.5–3 days), and the mean follow-up time was 1.0 year (range 1 month to 2.86 years). Functional outcomes are similar to those of open callosotomy, with the greatest effect in patients with a significant component of drop attacks in their seizure semiology. One patient achieved an Engel class II outcome after anterior two-thirds callosotomy resulting in only rare seizures at the 18-month follow-up. Four others were in Engel class III and 5 were Engel class IV. Hemorrhage occurred in 1 patient at the time of removal of the laser fiber, which was placed through the bone flap of a prior open partial callosotomy.

CONCLUSIONS LITT appears to be a safe and effective means for performing corpus callosotomy. Additional data are needed to confirm equipoise between open craniotomy and LITT for corpus callosotomy.

Posted on

Small intracranial aneurysms in the Barrow Ruptured Aneurysm Trial (BRAT)

Acta Neurochirurgica (2021) 163:123–129

Treatment of small ruptured aneurysms (SRAs) remains controversial, with literature reporting difficulty with endovascular versus microsurgical approaches. This paper analyzes outcomes after endovascular coiling and microsurgical clipping among patients with SRAs prospectively enrolled in the Barrow Ruptured Aneurysm Trial (BRAT).

Method All BRAT patients were included in this study. Patient demographics, aneurysm size, aneurysm characteristics, procedure-related complications, and outcomes at discharge and at 1-year and 6-year follow-up were evaluated. A modified Rankin scale (mRS) score > 2 was considered a poor outcome.

Results Of 73 patients with SRAs, 40 were initially randomly assigned to endovascular coiling and 33 to microsurgical clipping. The rate of treatment crossover was significantly different between coiling and clipping; 25 patients who were assigned to coiling crossed over to clipping, and no clipping patients crossed over to coiling (P < 0.001). Among SRA patients, 15 underwent coiling and 58 underwent clipping; groups did not differ significantly in demographic characteristics or aneurysm type (P ≥ 0.11). Mean aneurysm diameter was significantly greater in the endovascular group (3.0 ± 0.3 vs 2.6 ± 0.6; P = 0.02). The incidence of procedure-related complications was similar for endovascular and microsurgical treatments (odds ratio [95% confidence interval], 1.0 [0.1–10.0], P = 0.98). Both groups had comparable overall outcome (mRS score > 2) at discharge and 1-year and 6-year follow-up (P = 0.48 and 0.73, respectively).

Conclusions Most SRA patients in the BRAT underwent surgical clipping, with a high rate of crossover from endovascular approaches. Endovascular treatment was equivalent to surgical clipping with regard to procedure-related complications and neurologic outcomes.

Proudly powered by WordPress