Chronic subdural hematoma-incidence, complications, and financial impact.

OBJECTIVE: To examine the population-based incidence, complications, and total, direct hospital costs of chronic subdural hematoma (CSDH) treatment in a neurosurgical clinic during a 26-year period. The aim was also to estimate the necessity of planned postoperative follow-up computed tomography (CT). METHODS: A retrospective cohort (1990-2015) of adult patients living in Pirkanmaa, Finland, with a CSDH was identified using ICD codes and verified by medical records (n = 1148, median age = 76 years, men = 65%). Data collection was performed from medical records. To estimate the total, direct hospital costs, all costs from hospital admission until the last neurosurgical follow-up visit were calculated. All patients were followed until death or the end of 2017. The annual number of inhabitants in the Pirkanmaa Region was obtained from the Statistics Finland (Helsinki, Finland). RESULTS: The incidence of CSDH among the population 80 years or older has increased among both operatively (from 36.6 to 91/100,000/year) and non-operatively (from 4.7 to 36.9/100,000/year) treated cases. Eighty-five percent (n = 978) underwent surgery. Routine 4-6 weeks' postoperative follow-up CT increased the number of re-operations by 18% (n = 49). Most of the re-operations (92%) took place within 2 months from the primary operation. Patients undergoing re-operations suffered more often from seizures (10%, n = 28 vs 3.9%, n = 27; p < 0.001), empyema (4.3%, n = 12 vs 1.1%, n = 8; p = 0.002), and pneumonia (4.7%, n = 13 vs 1.4%, n = 12; p = 0.008) compared with patients with no recurrence. The treatment cost for recurrent CSDHs was 132% higher than the treatment cost of non-recurrent CSDHs, most likely because of longer hospital stay for re-admissions and more frequent outpatient follow-up with CT. The oldest group of patients, 80 years or older, was not more expensive than the others, nor did this group have more frequent complications, besides pneumonia. CONCLUSIONS: Based on our population-based study, the number of CSDH patients has increased markedly during the study period (1990-2015). Reducing recurrences is crucial for reducing both complications and costs. Greater age was not associated with greater hospital costs related to CSDH. A 2-month follow-up period after CSDH seems sufficient for most, and CT controls are advocated only for symptomatic patients.

Cranioplasty with Adipose-Derived Stem Cells, Beta-Tricalcium Phosphate Granules and Supporting Mesh: Six-Year Clinical Follow-Up Results.

Several alternative techniques exist to reconstruct skull defects. The complication rate of the cranioplasty procedure is high and the search for optimal materials and techniques continues. To report long-term results of patients who have received a cranioplasty using autologous adipose-derived stem cells (ASCs) seeded on beta-tricalcium phosphate (betaTCP) granules. Between 10/2008 and 3/2010, five cranioplasties were performed (four females, one male; average age 62.0 years) using ASCs, betaTCP granules and titanium or resorbable meshes. The average defect size was 8.1 × 6.7 cm2 . Patients were followed both clinically and radiologically. The initial results were promising, with no serious complications. Nevertheless, in the long-term follow-up, three of the five patients were re-operated due to graft related problems. Two patients showed marked resorption of the graft, which led to revision surgery. One patient developed a late infection (7.3 years post-operative) that required revision surgery and removal of the graft. One patient had a successfully ossified graft, but was re-operated due to recurrence of the meningioma 2.2 years post-operatively. One patient had an uneventful clinical follow-up, and the cosmetic result is satisfactory, even though skull x-rays show hypodensity in the borders of the graft. Albeit no serious adverse events occurred, the 6-year follow-up results of the five cases are unsatisfactory. The clinical results are not superior to results achieved by conventional cranial repair methods. The use of stem cells in combination with betaTCP granules and supporting meshes in cranial defect reconstruction need to be studied further before continuing with clinical trials. Stem Cells Translational Medicine 2017;6:1576-1582.

Imaging of Anterior Nucleus of Thalamus Using 1.5T MRI for Deep Brain Stimulation Targeting in Refractory Epilepsy.

BACKGROUND: Deep brain stimulation (DBS) of the anterior nucleus of thalamus (ANT) is an evolving treatment option in refractory focal epilepsy. Due to poor visualization of ANT in traditional MRI sequences used for movement disorder surgery, targeting of ANT is mainly based on stereotactic atlas information. Sophisticated 3T MRI methods enable visualization of ANT, but 1.5T MRI is still preferred or more readily available in a large number of centers performing DBS. OBJECTIVE: In the present study, we sought to determine whether ANT could be adequately visualized at 1.5T MRI pre- and postoperatively using imaging techniques similar to the ones visualizing ANT in 3T MRI. A total of 15 MRI examinations with short tau inversion recovery (STIR) and T1-weighted magnetization prepared gradient echo (MPRAGE) images were performed to visualize ANT in nonepileptic subjects (n = 2), patients with vagus nerve stimulator (VNS) (n = 3), stereotactic MRI (n = 3), patients with ANT-DBS (n = 7). RESULTS: ANT was distinctly visualized in STIR and T1-weighted MPRAGE images in patients without implanted stimulators, with Leksell stereotactic frame and with fully implanted VNS. Postoperative 1.5T MRI was able to demonstrate some of the anatomical landmarks around ANT enabling assessment of electrode contact locations. CONCLUSIONS: The visualization of ANT is possible in preoperative 1.5T MRI enabling direct targeting of ANT all examined situations. The use of indirect targeting and its inherent potential for lead misplacement due to anatomical variation may be avoided using these MRI methods. Furthermore, postoperative MRI with STIR and T1-weighted MPRAGE images enable detailed postoperative assessment of contact locations.

The Correlation between Intraoperative Microelectrode Recording and 3-Tesla MRI in Patients Undergoing ANT-DBS for Refractory Epilepsy.

BACKGROUND: Deep brain stimulation (DBS) of the anterior nucleus of the thalamus) (ANT) has been suggested as a treatment option in refractory epilepsy. The targeting of ANT is especially challenging due to its poor visualization in commonly used MRI sequences, lack of easily observable symptom relief during surgery and high degree of anatomical variation between individuals. OBJECTIVES: To study whether intraoperative microelectrode recording (MER), a method widely used in movement disorder surgery, provides clinically relevant information during the ANT-DBS implantation procedure. METHODS: A total of 186 MER samples from 5 patients and 10 thalami obtained from ANT-DBS surgery for refractory epilepsy were analyzed with respect to the signal characteristics and location in 3-tesla (3T) MRI STIR (short T1 inversion recovery) images. The location of each MER sample was calculated relative to visible borders of the ANT after correction of the sample locations according to the position of the final DBS electrode in postoperative CT-MRI fusion images. RESULTS: We found that the lateral aspect of the ANT lacked spiking activity consistent with the presence of white matter. The spike frequency in samples correlating with location at the ANT showed significantly lower spike frequency compared to samples correlating with location at the ventral anterior nucleus (median 3.0 and 7.0 spikes/2 s; p < 0.05), but spike bursts were morphologically similar in appearance. Trajectories entering the dorsomedial nucleus according to 3T MRI STIR images showed a yet different firing pattern with more low-amplitude regular activity. CONCLUSIONS: Our data suggest that MER provides clinically relevant information during implantation surgery by demonstrating both nucleus-specific neuronal firing patterns and white matter laminae between different nuclear groups.

Possible confounding factors on cerebral diffusion tensor imaging measurements.

BACKGROUND: Diffusion tensor imaging (DTI) is prone to numerous systemic confounding factors that should be acknowledged to avoid false conclusions. PURPOSE: To investigate the possible effects of age, gender, smoking, alcohol consumption, and education on cerebral DTI parameters in a generally healthy homogenous sample with no neurological or psychiatric diseases. MATERIAL AND METHODS: Forty (n = 40) subjects (mean age, 40.3 years; SD, 12.3) underwent brain DTI with 3 T magnetic resonance imaging (MRI). At enrolment, all the subjects were interviewed with respect to general health, education, history of smoking, and alcohol consumption. Studied DTI parameters included: (i) fractional anisotropy (FA); and (ii) apparent diffusion coefficient (ADC). Region-of-interest (ROI)-based measurements were estimated at 13 anatomical locations bilaterally on the axial images, except for the corpus callosum in which the ROIs were placed on the sagittal images. Circular ROI measurements were mainly used. Freehand ROI method was used with the forceps minor, uncinate fasciculus, and thalamus. Intra-observer variability and repeatability were assessed. RESULTS: The most consistent finding was that aging decreased FA values in the frontal brain regions. Regarding the other confounding factors, the results were discontinuous and no concrete conclusions could be drawn from these findings. In general, intra-observer repeatability of the DTI measurement was considered relatively good. CONCLUSION: Age should be noted as considerable confounding factors in ROI-based DTI analysis. More research on the effects of gender, smoking, alcohol consumption, and education is needed.

A multicentre, prospective, randomized, controlled study to evaluate the use of a fibrin sealant as an adjunct to sutured dural repair.

BACKGROUND: Obtaining intra-operative watertight closure of the dura is considered important in reducing post-operative cerebrospinal fluid (CSF) leak. The purpose of this study was to evaluate a fibrin sealant as an adjunct to sutured dural repair to obtain intra-operative watertight closure in cranial neurosurgery. METHODS: This randomized, controlled multicenter study compared a fibrin sealant (EVICEL® Fibrin Sealant [Human]) to sutured dural closure (Control). Subjects underwent supratentorial or posterior fossa procedures. Following primary dural repair by sutures, the closure was evaluated for intra-operative CSF leak by moderately increasing the intracranial pressure. If present, subjects were randomized to EVICEL® or additional sutures (2:1 ratio), stratified by surgical approach. Following treatment, subjects were successful if no CSF leaks were present during provocative challenge. Safety was assessed to 30 days post-surgery, including incidence of CSF leakage. RESULTS: One hundred and thirty-nine subjects were randomized: 89 to EVICEL® and 50 to Control. Intra-operative watertight closure was achieved in 92.1% EVICEL®-treated subjects versus 38.0% controls; a treatment difference of 54.1% (p < 0.001). The treatment differences in the supratentorial and posterior fossa strata were 49.1% and 75.7%, respectively (p < 0.001). The incidence of adverse events was similar between treatment groups. No deaths or unexpected serious adverse drug reactions were reported. CSF leakage within 30 days post-operatively was 2.2% and 2.0% in EVICEL® and control groups, respectively. In addition, 2 cases of CSF rhinorrhoea were observed in the EVICEL® group. Although not associated with the suture line where EVICEL® was applied, when combined with the other CSF leaks, the observed leak rate in the EVICEL® group was 4.5%. CONCLUSIONS: These results indicate that EVICEL® is effective as an adjunct to dural sutures to provide watertight closure of the dura mater in cranial surgery. The study confirmed the safety profile of EVICEL®.

Adipose stem cells used to reconstruct 13 cases with cranio-maxillofacial hard-tissue defects.

Although isolated reports of hard-tissue reconstruction in the cranio-maxillofacial skeleton exist, multipatient case series are lacking. This study aimed to review the experience with 13 consecutive cases of cranio-maxillofacial hard-tissue defects at four anatomically different sites, namely frontal sinus (3 cases), cranial bone (5 cases), mandible (3 cases), and nasal septum (2 cases). Autologous adipose tissue was harvested from the anterior abdominal wall, and adipose-derived stem cells were cultured, expanded, and then seeded onto resorbable scaffold materials for subsequent reimplantation into hard-tissue defects. The defects were reconstructed with either bioactive glass or ß-tricalcium phosphate scaffolds seeded with adipose-derived stem cells (ASCs), and in some cases with the addition of recombinant human bone morphogenetic protein-2. Production and use of ASCs were done according to good manufacturing practice guidelines. Follow-up time ranged from 12 to 52 months. Successful integration of the construct to the surrounding skeleton was noted in 10 of the 13 cases. Two cranial defect cases in which nonrigid resorbable containment meshes were used sustained bone resorption to the point that they required the procedure to be redone. One septal perforation case failed outright at 1 year because of the postsurgical resumption of the patient's uncontrolled nasal picking habit.

The developing management of esthesioneuroblastoma: a single institution experience.

Esthesioneuroblastoma remains a challenging disease because of its rarity, the complexity of surrounding structures, missing opinions of optimal treatment protocol, and complications associated with necessary surgery. Our objective was to analyse the management and outcome of a cohort of patients with esthesioneuroblastoma from 1990 to 2009 in a tertiary medical centre. There were 17 eligible patients (8 males and 9 females) with the median age of 53 years (range 20-75 years). An obvious inconsistency was noted in the management of the various tumours of the present series during the two decades due to a lack of a uniform treatment protocol. The median follow-up time was 57.5 months (range 3-158 months). Nine patients (seven with curative treatment intent) died of the disease with the median time from diagnosis to death of 60 months (range 3-161 months). Eight patients had no evidence of the disease at last follow-up visit (median 76 months, range 24-119 months). Recurrences were documented in seven of the patients. The median time from end of primary treatment to a recurrence was 57 months (range 6-110 months). The 5-year overall survival and disease-free survival was 68 and 62%, respectively. The management of ENB should be planned by an experienced head and neck surgeon as part of a multidisciplinary team in a tertiary referral setting. Multimodality therapy with long-term follow-up is preferable and should be set based on the available disease-specific classifications for clinical staging and histopathological grading.

Microvascular free flap reconstruction of skull base penetrating tumors.

This is a follow-up study of 31 consecutive patients who underwent skull base tumor resection and microvascular tissue reconstruction in anterior and middle cranial fossa. Parameters recorded included factors related to operation, hospital stay, and outcome. All patients had a minimum follow-up of 5 years. There were no flap losses and no reoperations due to anastomoses-related complications. Five of 30 patients had cerebrospinal fluid leak that resolved with spinal drain except in one case, where the flap was placed incorrectly and the patient died of meningitis. Two other patients died due to early complications of the surgery. Although the complication rate was quite high, we consider this type of surgery worth performing, and even palliative surgery is to be considered in selective cases. Rectus abdominis flap due to its pliability and long pedicle proved to be most suitable flap together with superficial temporal artery and vein as recipient vessels.

Cranioplasty with adipose-derived stem cells and biomaterial: a novel method for cranial reconstruction.

BACKGROUND: There is no optimal method for reconstruction of large calvarial defects. Because of the limitations of autologous bone grafts and alloplastic materials, new methods for performing cranioplasties are needed. OBJECTIVE: To create autologous bone to repair cranial defects. METHODS: We performed a cranioplasty procedure with this new method in 4 patients who had large calvarial defects of different etiologies. We used autologous adipose-derived stem cells seeded in beta-tricalcium phosphate granules. For 2 patients, we used a bilaminate technique with resorbable mesh. RESULTS: During follow-up, there were no clinically relevant postoperative complications. The computed tomography scans revealed satisfactory outcome in ossification, and in the clinical examinations, the outcomes were good. The cranioplasty was measured in Hounsfield units from each computed tomography scan. The Hounsfield units increased gradually to equal the value of bone. CONCLUSION: The combination of scaffold material such as beta-tricalcium phosphate and autologous adipose-derived stem cells constitutes a promising model for reconstruction of human large cranial defects. The success of these clinical cases paves way for further studies and clinical applications to turn this method into a reliable treatment regimen.

Cost-utility analysis of routine neurosurgical spinal surgery.

OBJECT: Cost-utility analysis is currently the preferred method with which to compare the cost-effectiveness of various interventions. The authors conducted a study to establish the cost-utility results of routine neurosurgery-based spinal interventions by examining patient-derived values. METHODS: Two hundred seventy patients undergoing surgery for cervical or lumbar radicular pain filled in the 15-dimensional health-related quality of life (HRQOL) questionnaire before and 3 months after surgery. Quality-adjusted life years (QALYs) were calculated using the utility data and the expected remaining life years of the patients. The mean HRQOL score (scale, 0-1) increased after cervical surgery (169 patients, mean age 52 years, 40% women) from 0.81 +/- 0.11 preoperatively, to 0.85 +/- 0.11 at 3 months, and after lumbar surgery (101 patients, mean age 54 years, 59% women) from 0.79 +/- 0.10 preoperatively, to 0.85 +/- 0.12 at 3 months (p < 0.001). Of the 15 dimensions of health, improvement in the following was documented in both groups: sleeping, usual activities, discomfort and symptoms, depression, distress, vitality, and sexual activity (p < 0.05). The cost per QALY gained was Euro 2774 and 1738 for cervical and lumbar operations, respectively. In cases in which surgery was delayed the cost per QALY was doubled. CONCLUSIONS: Spinal surgery led to a statistically significant and clinically important improvement in HRQOL. The cost per QALY gained was reasonable, less than half of that observed, for example, for hip replacement surgery or angioplasty treatment of coronary artery disease; however, a prolonged delay in surgical intervention led to an approximate doubling of the cost per QALY gained by the treatment.

Routine cerebral angiography after surgery for saccular aneurysms: is it worth it?

OBJECTIVE: The objective of this study was to determine whether an angiographically proven rate of saccular intracranial aneurysm occlusion after surgical clipping suggests that postoperative angiography should continue to be used routinely or should be supplanted by intraoperative angiography. These data also should establish a basis for comparing surgery with new endovascular methods of treatment. METHODS: During a 3.5-year period, a consecutive series of 622 patients (955 aneurysms, 808 of which were surgically clipped) who underwent postoperative angiography were studied retrospectively. This series comprised 493 ruptured and 315 unruptured aneurysms. RESULTS: Complete aneurysm closure was achieved in 88% of aneurysms, a neck remnant was discovered in 9%, and a fundus remnant was revealed in 3%. Of 493 ruptured aneurysms, 86% were completely occluded. Of 315 unruptured aneurysms, 91% were completely occluded. The results for clipping of complex aneurysms, i.e., posterior circulation or large to giant aneurysms, were significantly inferior to those for small and anterior circulation aneurysms. In one-third of the large and giant aneurysms, a part of the base was left intentionally because of calcifications or strong wall or to prevent occlusion of any branches. In the series, a significant 5% complication rate of major vessel occlusion was detected. CONCLUSION: Our retrospective analysis revealed that ruptured, posterior circulation, and large/giant aneurysms are more prone to incomplete clipping. Therefore, these aneurysms require postoperative if not intraoperative evaluation with angiography. Many clippings of anterior circulation aneurysms experience unexpected failures, which suggests that intraoperative angiography could be beneficial. This series, which has no selection bias, can be used as a basis to compare the results of other series reporting surgical or endovascular treatment.