10-year follow-up after implantation of the Bryan Cervical Disc Prosthesis.

PURPOSE: Cervical arthroplasty is being used as an alternative for cervical fusion, but long-term follow-up results have rarely been reported. In this paper, we present 10-year follow-up results after implantation of the Bryan Cervical Disc Prosthesis in a single center. METHODS: 89 patients underwent implantation of a single-level Bryan Cervical Disc Prosthesis to treat radiculopathy and/or myelopathy. Clinical (Neurological Success, Neck Disability Index (NDI), Neck- and Arm-Pain, and SF-36) and radiological follow-up was prospectively organized up to 10 years after surgery. Adverse events and second surgeries were recorded and evaluated. RESULTS: Ten-year follow-up data were available for 72 (81%) patients. Maintenance or improvement of the neurological state was seen in 89% of patients after 10-year follow-up. SF-36 PCS scores improved significantly at all follow-up points. SF-36 MCS improvement was significant at 4 and 6 year, but not at 8- and 10-year follow-up. Significant improvement for NDI, and Neck- and Arm-Pain scores was found for the subgroup of patients in whom these data were available. Mean angular motion of the prosthesis at 10-year follow-up was 8.6°. Mobility of the device, defined as >2° of angular motion, was reached in 81% of patients. During the study period, 21 patients (24%) developed new or recurrent radiculopathy or myelopathy, the majority of these being treated conservatively. Seven patients (8%) required 8 additional spine surgeries to treat persistent or recurrent symptoms. Of these, 2 patients (2%) were reoperated at the index level and at 5 (6%) an adjacent level. CONCLUSION: In this study, favorable long-term clinical outcome after implantation of the Bryan Cervical Disc Prosthesis was seen, with the majority of prostheses remaining mobile after 10-year follow-up. However, still 6% of patients required adjacent level surgery.

Meox2/Tcf15 heterodimers program the heart capillary endothelium for cardiac fatty acid uptake.

BACKGROUND: Microvascular endothelium in different organs is specialized to fulfill the particular needs of parenchymal cells. However, specific information about heart capillary endothelial cells (ECs) is lacking. METHODS AND RESULTS: Using microarray profiling on freshly isolated ECs from heart, brain, and liver, we revealed a genetic signature for microvascular heart ECs and identified Meox2/Tcf15 heterodimers as novel transcriptional determinants. This signature was largely shared with skeletal muscle and adipose tissue endothelium and was enriched in genes encoding fatty acid (FA) transport-related proteins. Using gain- and loss-of-function approaches, we showed that Meox2/Tcf15 mediate FA uptake in heart ECs, in part, by driving endothelial CD36 and lipoprotein lipase expression and facilitate FA transport across heart ECs. Combined Meox2 and Tcf15 haplodeficiency impaired FA uptake in heart ECs and reduced FA transfer to cardiomyocytes. In the long term, this combined haplodeficiency resulted in impaired cardiac contractility. CONCLUSIONS: Our findings highlight a regulatory role for ECs in FA transfer to the heart parenchyma and unveil 2 of its intrinsic regulators. Our insights could be used to develop new strategies based on endothelial Meox2/Tcf15 targeting to modulate FA transfer to the heart and remedy cardiac dysfunction resulting from altered energy substrate usage.

Selectivity for three-dimensional shape and grasping-related activity in the macaque ventral premotor cortex.

Anatomical studies indicate that area F5 in the macaque ventral premotor cortex consists of three different sectors. One of these is F5a in the posterior bank of the inferior arcuate sulcus, but no functional characterization of F5a at the single-cell level exists. We investigated the neuronal selectivity for three-dimensional (3D) shape and grasping activity in F5a. In contrast to neighboring regions F5p and 45B, the great majority of F5a neurons showed selectivity for disparity-defined curved surfaces, and most neurons preserved this selectivity across positions in depth, indicating higher-order disparity selectivity. Thus, as predicted by monkey fMRI data, F5a neurons showed robust 3D-shape selectivity in the absence of a motor response. To investigate the relationship between disparity selectivity and grasping activity, we recorded from 3D-shape-selective F5a neurons during a visually guided grasping task and during grasping in the dark. F5a neurons encoding the depth profile of curved surfaces frequently responded during grasping of real-world objects in the light, but not in the dark, whereas nearby neurons were also active in the dark. The presence of 3D-shape-selective and "visual-dominant" neurons demonstrates that the F5a sector is distinct from neighboring regions of ventral premotor cortex, in line with recent anatomical connectivity studies.

Three-dimensional shape coding in grasping circuits: a comparison between the anterior intraparietal area and ventral premotor area F5a.

Depth information is necessary for adjusting the hand to the three-dimensional (3-D) shape of an object to grasp it. The transformation of visual information into appropriate distal motor commands is critically dependent on the anterior intraparietal area (AIP) and the ventral premotor cortex (area F5), particularly the F5p sector. Recent studies have demonstrated that both AIP and the F5a sector of the ventral premotor cortex contain neurons that respond selectively to disparity-defined 3-D shape. To investigate the neural coding of 3-D shape and the behavioral role of 3-D shape-selective neurons in these two areas, we recorded single-cell activity in AIP and F5a during passive fixation of curved surfaces and during grasping of real-world objects. Similar to those in AIP, F5a neurons were either first- or second-order disparity selective, frequently showed selectivity for discrete approximations of smoothly curved surfaces that contained disparity discontinuities, and exhibited mostly monotonic tuning for the degree of disparity variation. Furthermore, in both areas, 3-D shape-selective neurons were colocalized with neurons that were active during grasping of real-world objects. Thus, area AIP and F5a contain highly similar representations of 3-D shape, which is consistent with the proposed transfer of object information from AIP to the motor system through the ventral premotor cortex.

Selectivity for three-dimensional contours and surfaces in the anterior intraparietal area.

The macaque anterior intraparietal area (AIP) is crucial for visually guided grasping. AIP neurons respond during the visual presentation of real-world objects and encode the depth profile of disparity-defined curved surfaces. We investigated the neural representation of curved surfaces in AIP using a stimulus-reduction approach. The stimuli consisted of three-dimensional (3-D) shapes curved along the horizontal axis, the vertical axis, or both the horizontal and the vertical axes of the shape. The depth profile was defined solely by binocular disparity that varied along either the boundary or the surface of the shape or along both the boundary and the surface of the shape. The majority of AIP neurons were selective for curved boundaries along the horizontal or the vertical axis, and neural selectivity emerged at short latencies. Stimuli in which disparity varied only along the surface of the shape (with zero disparity on the boundaries) evoked selectivity in a smaller proportion of AIP neurons and at considerably longer latencies. AIP neurons were not selective for 3-D surfaces composed of anticorrelated disparities. Thus the neural selectivity for object depth profile in AIP is present when only the boundary is curved in depth, but not for disparity in anticorrelated stereograms.

Stratification according to HGG-IMMUNO RPA model predicts outcome in a large group of patients with relapsed malignant glioma treated by adjuvant postoperative dendritic cell vaccination.

PURPOSE: Adult patients with relapsed high-grade glioma are a very heterogenous group with, however, an invariably dismal prognosis. We stratified patients with relapsed high-grade glioma treated with re-operation and postoperative dendritic cell (DC) vaccination according to a simple recursive partitioning analysis (RPA) model to predict outcome. PATIENTS AND METHODS: Based on age, pathology, Karnofsky performance score, and mental status, 117 adult patients with relapsed malignant glioma, undergoing re-operation, and postoperative adjuvant dendritic cell (DC) vaccination were stratified into 4 classes. Kaplan-Meier survival estimates were generated for each class of this HGG-IMMUNO RPA model. Extent of resection was documented but not included in the prognostic model. RESULTS: Kaplan-Meier overall survival estimates revealed significant (p < 0.0001) differences among the 4 HGG-IMMUNO RPA classes. Long-term survivors, surviving more than 24 months after the re-operation and vaccination, are seen in 54.5, 26.7, 11.5, and 0 % for the classes I, II, III, and IV respectively. CONCLUSION: This HGG-IMMUNO RPA classification is able to predict overall survival in a large group of adult patients with a relapsed malignant glioma, treated with re-operation and postoperative adjuvant DC vaccination in the HGG-IMMUNO-2003 cohort comparison trial. The model appears useful for prognostic patient counseling for patients participating in DC vaccination trials. A substantial number of long-term survivors after relapse are seen in class I to III, but not in class IV patients.

Integration of autologous dendritic cell-based immunotherapy in the standard of care treatment for patients with newly diagnosed glioblastoma: results of the HGG-2006 phase I/II trial.

PURPOSE: Dendritic cell (DC)-based tumor vaccination has rendered promising results in relapsed high-grade glioma patients. In the HGG-2006 trial (EudraCT 2006-002881-20), feasibility, toxicity, and clinical efficacy of the full integration of DC-based tumor vaccination into standard postoperative radiochemotherapy are studied in 77 patients with newly diagnosed glioblastoma. PATIENTS AND METHODS: Autologous DC are generated after leukapheresis, which is performed before the start of radiochemotherapy. Four weekly induction vaccines are administered after the 6-week course of concomitant radiochemotherapy. During maintenance chemotherapy, 4 boost vaccines are given. Feasibility and progression-free survival (PFS) at 6 months (6mo-PFS) are the primary end points. Overall survival (OS) and immune profiling, rather than monitoring, as assessed in patients' blood samples, are the secondary end points. Analysis has been done on intent-to-treat basis. RESULTS: The treatment was feasible without major toxicity. The 6mo-PFS was 70.1 % from inclusion. Median OS was 18.3 months. Outcome improved significantly with lower EORTC RPA classification. Median OS was 39.7, 18.3, and 10.7 months for RPA classes III, IV, and V, respectively. Patients with a methylated MGMT promoter had significantly better PFS (p = 0.0027) and OS (p = 0.0082) as compared to patients with an unmethylated status. Exploratory "immunological profiles" were built to compare to clinical outcome, but no statistical significant evidence was found for these profiles to predict clinical outcome. CONCLUSION: Full integration of autologous DC-based tumor vaccination into standard postoperative radiochemotherapy for newly diagnosed glioblastoma seems safe and possibly beneficial. These results were used to power the currently running phase IIb randomized clinical trial.

The Latest Lessons Learned from Retrieval Analyses of Ultra-High Molecular Weight Polyethylene, Metal-on-Metal, and Alternative Bearing Total Disc Replacements.

Knowledge regarding the in vivo performance and periposthetic tissue response of cervical and lumbar total disc replacements (TDRs) continues to expand. This review addresses the following four main questions: 1) What are the latest lessons learned from polyethylene in large joints and how are they relevant to current TDRs? 2) What are the latest lessons learned regarding adverse local tissue reactions from metal-on-metal, CoCr bearings in large joints and how are they relevant to current TDRs? 3) What advancements have been made in understanding the in vivo performance of alternative biomaterials, such as stainless steel and polycarbonate urethane, for TDRs in the past five years? 4) How has retrieval analysis of all these various artificial disc bearing technologies advanced the state of the art in preclinical testing of TDRs? The study of explanted artificial discs and their associated tissues can help inform bearing selection as well as the design of future generations of disc arthroplasty. Analyzing retrieved artificial discs is also essential for validating preclinical test methods.

Integration of autologous dendritic cell-based immunotherapy in the primary treatment for patients with newly diagnosed glioblastoma multiforme: a pilot study.

Despite resection, radiochemotherapy, and maintenance temozolomide chemotherapy (TMZm), the prognosis of patients with glioblastoma multiforme (GBM) remains poor. We integrated immunotherapy in the primary standard treatment for eight pilot adult patients (median age 50 years) with GBM, to assess clinical and immunological feasibility and toxicity in preparation of a phase I/II protocol HGG-2006. After maximum, safe resection, leukapheresis was performed before radiochemotherapy, and four weekly vaccinations with autologous GBM lysate-loaded monocyte-derived dendritic cells were given after radiochemotherapy. Boost vaccines with lysates were given during TMZm. During the course of vaccination, immunophenotyping showed a relative increase in CD8+CD25+ cells in six of the seven patients, complying with the prerequisites for implementation of immunotherapy in addition to postoperative radiochemotherapy. In five patients, a more than twofold increase in tumor antigen-reacting IFN-gamma-producing T cells on Elispot was seen at the fourth vaccination compared with before vaccination. In three of these five patients this more than twofold increase persisted after three cycles of TMZm. Quality of life during vaccination remained excellent. Progression-free survival at six months was 75%. Median overall survival for all patients was 24 months (range: 13-44 months). The only serious adverse event was an ischemic stroke eight months postoperatively. We conclude that tumor vaccination, fully integrated within the standard primary postoperative treatment for patients with newly diagnosed GBM, is feasible and well tolerated. The survival data were used to power a currently running phase I/II trial.

Postoperative segmental malalignment after surgery with the Bryan cervical disc prosthesis: is it related to the mechanics and design of the prosthesis?

STUDY DESIGN: In a radiographic study, postoperative segmental alignment was compared between 2 cohorts of 20 consecutive patients operated with a Bryan Cervical Disc Prosthesis. In group 2, patients with severe preoperative kyphosis were excluded for disc replacement surgery and the surgical technique was slightly altered to avoid asymmetric overdrilling of the posterior part of the cranial endplate of the caudal vertebral body. OBJECTIVE: The aim was to investigate whether this change in patient inclusion criteria and modification of the surgical technique had an influence on postoperative segmental alignment and whether postoperative kyphosis is related to the mechanical properties and/or the design of the prosthesis. SUMMARY OF BACKGROUND DATA: Several research groups reported segmental kyphosis after treatment of degenerative disc disease with the Bryan Cervical Disc Prosthesis. METHODS: On the basis of lateral radiographs, the disc insertion angle (as a postoperative estimate for the intraoperative angle of approach) and the angle of the functional spinal unit (FSU) and disc angle (both as measures for segmental alignment) were calculated. RESULTS: In group 1, 80% of the patients had a kyphotic FSU angle and 40% had a kyphotic disc angle preoperatively. At follow-up, 65% of the patients had a kyphotic FSU angle, whereas 55% had a kyphotic disc angle. In group 2, 40% of the patients had a kyphotic FSU angle and 5% had a kyphotic disc angle preoperatively. At follow-up, 40% of the patients had a kyphotic FSU angle, whereas 5% had a kyphotic disc angle. Due to the change in patient inclusion criteria, there was a significant difference in preoperative FSU angle between groups 1 and 2; however, no significant difference in preoperative disc angle was found. Owing to the change in surgical technique, the disc insertion angle was significantly different between both the groups. A difference in postoperative FSU angle, however, nonsignificant, between both the groups was observed. There was a significant difference in postoperative disc angle between both the groups; group 1 showed significantly more kyphosis of the shells, than group 2. CONCLUSIONS: This study shows that segmental malalignment with the Bryan Disc can be reduced and is therefore not device related. Proper patient selection and a modified surgical technique can prevent this adverse outcome.

Postoperative adjuvant dendritic cell-based immunotherapy in patients with relapsed glioblastoma multiforme.

PURPOSE: To investigate the therapeutic role of adjuvant vaccination with autologous mature dendritic cells (DC) loaded with tumor lysates derived from autologous, resected glioblastoma multiforme (GBM) at time of relapse. EXPERIMENTAL DESIGN: Fifty-six patients with relapsed GBM (WHO grade IV) were treated with at least three vaccinations. Children and adults were treated similarly in three consecutive cohorts, with progressively shorter vaccination intervals per cohort. Feasibility and toxicity were assessed as well as effect of age, extent of resection, Karnofsky Performance Score, and treatment cohort on the progression-free (PFS) and overall survival (OS) using univariable and multivariable analysis. RESULTS: Since the prevaccine reoperation, the median PFS and OS of the total group was 3 and 9.6 months, respectively, with a 2-year OS of 14.8%. Total resection was a predictor for better PFS both in univariable analysis and after correction for the other covariates. For OS, younger age and total resection were predictors of a better outcome in univariable analysis but not in multivariable analysis. A trend to improved PFS was observed in favor of the faster DC vaccination schedule with tumor lysate boosting. Vaccine-related edema in one patient with gross residual disease before vaccination was the only serious adverse event. CONCLUSION: Adjuvant DC-based immunotherapy for patients with relapsed GBM is safe and can induce long-term survival. A trend to PFS improvement was shown in the faster vaccination schedule. The importance of age and a minimal residual disease status at the start of the vaccination is underscored.

Qualitative and quantitative assessment of degeneration of cervical intervertebral discs and facet joints.

Degeneration of intervertebral discs and facet joints is one of the most frequently encountered spinal disorders. In order to describe and quantify degeneration and evaluate a possible relationship between degeneration and biomechanical parameters, e.g., the intervertebral range of motion and intradiscal pressure, a scoring system for degeneration is mandatory. However, few scoring systems for the assessment of degeneration of the cervical spine exist. Therefore, two separate objective scoring systems to qualitatively and quantitatively assess the degree of cervical intervertebral disc and facet joint degeneration were developed and validated. The scoring system for cervical disc degeneration consists of three variables which are individually scored on neutral lateral radiographs: "height loss" (0-4 points), "anterior osteophytes" (0-3 points) and "endplate sclerosis" (0-2 points). The scoring system for facet joint degeneration consists of four variables which are individually scored on neutral computed tomography scans: "hypertrophy" (0-2 points), "osteophytes" (0-1 point), "irregularity" on the articular surface (0-1 point) and "joint space narrowing" (0-1 point). Each variable contributes with varying importance to the overall degeneration score (max 9 points for the scoring system of cervical disc degeneration and max 5 points for facet joint degeneration). Degeneration of 20 discs and facet joints of 20 patients was blindly assessed by four raters: two neurosurgeons (one senior and one junior) and two radiologists (one senior and one junior), firstly based on first subjective impression and secondly using the scoring systems. Measurement errors and inter- and intra-rater agreement were determined. The measurement error of the scoring system for cervical disc degeneration was 11.1 versus 17.9% of the subjective impression results. This scoring system showed excellent intra-rater agreement (ICC = 0.86, 0.75-0.93) and excellent inter-rater agreement (ICC = 0.78, 0.64-0.88). Surgeons as well as radiologists and seniors as well as juniors obtained excellent inter- and intra-rater agreement. The measurement error of the scoring system for cervical facet joint degeneration was 20.1 versus 24.2% of the subjective impression results. This scoring system showed good intra-rater agreement (ICC = 0.71, 0.42-0.89) and fair inter-rater agreement (ICC = 0.49, 0.26-0.74). Both scoring systems fulfilled the criteria for recommendation proposed by Kettler and Wilke. Our scoring systems can be reliable and objective tools for assessing cervical disc and facet joint degeneration. Moreover, the scoring system of cervical disc degeneration was shown to be experience- and discipline-independent.

Albert Dereymaeker and Joseph Cyriel Mulier's description of anterior cervical discectomy with fusion in 1955.

Anterior cervical discectomy with fusion (ACDF) is a very well-known and often-performed procedure in the practice of spine surgeons. The earliest descriptions of the technique have always been attributed to Cloward, Smith, and Robinson. However, in the French literature, this procedure was also described by others during the exact same time period (in the 1950s). At a meeting in Paris in 1955, Belgians Albert Dereymaeker and Joseph Cyriel Mulier, a neurosurgeon and an orthopedic surgeon, respectively, described the technique that involved an anterior cervical discectomy and the placement of an iliac crest graft in the intervertebral disc space. In 1956, a summary of their oral presentation was published, and a subsequent paper-an illustrated description of the technique and the details of a larger case series with a 3.5-year follow-up period-followed in 1958. The list of authors who first described ACDF should be completed by adding Dereymaeker's and Mulier's names. They made an important contribution to the practice of spinal surgery that was not generally known because they published in French.

Biomechanics of frontal skull fracture.

The purpose of the present study was to investigate whether an energy failure level applies to the skull fracture mechanics in unembalmed post-mortem human heads under dynamic frontal loading conditions. A double-pendulum model was used to conduct frontal impact tests on specimens from 18 unembalmed post-mortem human subjects. The specimens were isolated at the occipital condyle level, and pre-test computed tomography images were obtained. The specimens were rigidly attached to an aluminum pendulum in an upside down position and obtained a single degree of freedom, allowing motion in the plane of impact. A steel pendulum delivered the impact and was fitted with a flat-surfaced, cylindrical aluminum impactor, which distributed the load to a force sensor. The relative displacement between the two pendulums was used as a measure for the deformation of the specimen in the plane of impact. Three impact velocity conditions were created: low (3.60+/-0.23 m/sec), intermediate (5.21+/-0.04 m/sec), and high (6.95+/-0.04 m/sec) velocity. Computed tomography and dissection techniques were used to detect pathology. If no fracture was detected, repeated tests on the same specimen were performed with higher impact energy until fracture occurred. Peak force, displacement and energy variables were used to describe the biomechanics. Our data suggests the existence of an energy failure level in the range of 22-24 J for dynamic frontal loading of an intact unembalmed head, allowed to move with one degree of freedom. Further experiments, however, are necessary to confirm that this is a definitive energy criterion for skull fracture following impact.

Lateral head impacts and protection of the temporal area by bicycle safety helmets.

BACKGROUND: The protective effectiveness of bicycle helmets has been demonstrated in several epidemiologic studies. However, the temple region is only minimally covered by most helmet models. Impact tests were performed on human cadavers to investigate whether current bicycle helmets are capable of preventing direct contact on the temporal area in side impacts. METHODS: Lateral head impacts, corresponding to a force load of 15,000 N on an nonhelmeted head, were applied on 11 helmeted cadavers by a steel pendulum with a flat impact surface, and the contact between the impactor plate and the temporal and zygomatic area was investigated by means of paint transfer. In eight tests, a common design bicycle helmet was used, whereas in three tests the helmets provided larger temporal coverage (temporal helmet edge <10 mm above Frankfort plane). The skulls were inspected for fractures. RESULTS: In seven of the eight tests with common design bicycle helmets, contact had occurred and in one of these a skull fracture was seen. The helmets with a larger temporal coverage consistently prevented such contact loading. CONCLUSIONS: The common designs of commercially available bicycle helmets do not prevent direct contact loading on the temporal and zygomatic arch region and this contact loading is potentially harmful. The present preliminary study strongly questions the effectiveness of these helmets in providing accurate protection of the temporal and zygomatic area.

Mechanics of acute subdural hematomas resulting from bridging vein rupture.

OBJECT: Based on data from primate experiments it is known that rotational acceleration in the sagittal plane and in a forward direction is most likely to produce acute subdural hematomas due to bridging vein rupture. For protection against these lesions, knowledge of rotational acceleration tolerance levels in humans is required. In the present study the authors analyze human tolerance levels for bridging vein rupture by performing head impact tests in cadavers. METHODS: Ten unembalmed cadavers were subjected to 18 occipital impacts producing head rotation in the sagittal plane with varying rotational acceleration magnitudes and pulse durations. Rotational acceleration was calculated from the linear acceleration histories recorded by three uniaxial accelerometers mounted on the side of the head. Bridging vein ruptures were detected by injecting contrast dye into the superior sagittal sinus under fluoroscopy and by autopsy procedures. Bridging vein ruptures were produced in six head impact tests: one test with a pulse duration of 5.2 msec and a peak rotational acceleration of 13,411 rad/second2; three tests with a pulse duration between 7 and 8 msec and a peak rotational acceleration of 12,558, 10,607, and 8567 rad/second2; and two tests with a pulse duration longer than 10 msec and a peak rotational acceleration as low as 5267 rad/second2. CONCLUSIONS: This is the only cadaveric study of bridging vein rupture focused on short pulse durations, which are usually associated with falls. The data suggest a tolerance level of approximately 10,000 rad/second2 for pulse durations shorter than 10 msec, which seems to decrease for longer pulse durations.

Stereopsis after anterior temporal lobectomy.

Brain areas critical for stereopsis have been investigated in non-human primates but are largely unknown in the human brain. Microelectrode recordings and functional MRI (fMRI) studies in monkeys have shown that in monkeys the inferior temporal cortex is critically involved in 3D shape categorization. Furthermore, some human fMRI studies similarly suggest an involvement of visual areas in the temporal lobe in depth perception. We aimed to investigate the role of the human anterior temporal neocortex in stereopsis by assessing stereoscopic depth perception before and after anterior temporal lobectomy. Eighteen epilepsy surgery patients were tested, pre- and postoperatively, in 3 different depth discrimination tasks. Sensitivity for local and global disparity was tested in a near-far discrimination task and sensitivity for 3D curvature was assessed in a convex-concave discrimination task, where 3D shapes were presented at different positions in depth. We found no evidence that temporal lobe epilepsy surgery has a significant effect on stereopsis. In contrast with earlier findings, we conclude that local as well as global stereopsis is maintained after unilateral resection of the temporal pole in epilepsy surgery patients. Our findings, together with previous studies, suggest that in humans more posterior visual regions underlie depth perception.

Outcome after epilepsy surgery at the University Hospitals Leuven 1998-2012.

We performed a retrospective outcome study of 199 patients who underwent resective epilepsy surgery from 1998 to 2012 and had a minimum of one-year follow-up at the University Hospitals Leuven. Our aim was to assess seizure outcome, prognostic factors for seizure outcome and complication rate. Good seizure outcome after surgery was 38 % at 5 years and 34 % at 10 years follow-up. Good seizure outcome over the previous year at last follow-up, however, was 77 %, which could be explained by the 'running-down phenomenon', i.e. seizure freedom after initial recurrent epilepsy in 32 % of the patients, mainly after temporal lobe surgery. Good seizure outcome for at least 1 year at the last visit was 82 % for temporal and 62 % for extra-temporal lobe interventions. Other variables predictive of a good seizure outcome were not identified. Permanent complications of epilepsy surgery were observed in 31 %. The most important were word finding difficulties (22 %), depression (18 %) and memory deficits (12 %). In conclusion, epilepsy surgery is an excellent treatment option for selected patients, with a good seizure outcome in around 80 % of patients and complications in about 30 %.

Creating a normative database of age-specific 3D geometrical data, bone density, and bone thickness of the developing skull: a pilot study.

OBJECT: Finite element models (FEMs) of the head are used to study the biomechanics of traumatic brain injury and depend heavily on the use of accurate material properties and head geometry. Any FEM aimed at investigating traumatic head injury in children should therefore use age-specific dimensions of the head, as well as age-specific material properties of the different tissues. In this study, the authors built a database of age-corrected skull geometry, skull thickness, and bone density of the developing skull to aid in the development of an age-specific FEM of a child's head. Such a database, containing age-corrected normative skull geometry data, can also be used for preoperative surgical planning and postoperative long-term follow-up of craniosynostosis surgery results. METHODS: Computed tomography data were processed for 187 patients (age range 0-20 years old). A 3D surface model was calculated from segmented skull surfaces. Skull models, reference points, and sutures were processed into a MATLAB-supported database. This process included automatic calculation of 2D measurements as well as 3D measurements: length of the coronal suture, length of the lambdoid suture, and the 3D anterior-posterior length, defined as the sum of the metopic and sagittal suture. Skull thickness and skull bone density calculations were included. RESULTS: Cephalic length, cephalic width, intercoronal distance, lateral orbital distance, intertemporal distance, and 3D measurements were obtained, confirming the well-established general growth pattern of the skull. Skull thickness increases rapidly in the first year of life, slowing down during the second year of life, while skull density increases with a fast but steady pace during the first 3 years of life. Both skull thickness and density continue to increase up to adulthood. CONCLUSIONS: This is the first report of normative data on 2D and 3D measurements, skull bone thickness, and skull bone density for children aged 0-20 years. This database can help build an age-specific FEM of a child's head. It can also help to tailor preoperative virtual planning in craniosynostosis surgery toward patient-specific normative target values and to perform objective long-term follow-up in craniosynostosis surgery.

Decompression and paraspinous tension band: a novel treatment method for patients with lumbar spinal stenosis and degenerative spondylolisthesis.

BACKGROUND CONTEXT: Prior studies have demonstrated the superiority of decompression and fusion over decompression alone for the treatment of lumbar degenerative spondylolisthesis with spinal stenosis. More recent studies have investigated whether nonfusion stabilization could provide durable clinical improvement after decompression and fusion. PURPOSE: To examine the clinical safety and effectiveness of decompression and implantation of a novel flexion restricting paraspinous tension band (PTB) for patients with degenerative spondylolisthesis. STUDY DESIGN: A prospective clinical study. PATIENT SAMPLE: Forty-one patients (7 men and 34 women) aged 45 to 83 years (68.2 ± 9.0) were recruited with symptomatic spinal stenosis and Meyerding Grade 1 or 2 degenerative spondylolisthesis at L3-L4 (8) or L4-L5 (33). OUTCOME MEASURES: Self-reported measures included visual analog scale (VAS) for leg, back, and hip pain and the Oswestry Disability Index (ODI). Physiologic measures included quantitative and qualitative radiographic analysis performed by an independent core laboratory. METHODS: Patients with lumbar degenerative spondylolisthesis and stenosis were prospectively enrolled at four European spine centers with independent monitoring of data. Clinical and radiographic outcome data collected preoperatively were compared with data collected at 3, 6, 12, and 24 months after surgery. This study was sponsored by the PTB manufacturer (Simpirica Spine, Inc., San Carlos, CA, USA), including institutional research support grants to the participating centers totaling approximately US $172,000. RESULTS: Statistically significant improvements and clinically important effect sizes were seen for all pain and disability measurements. At 24 months follow-up, ODI scores were reduced by an average of 25.4 points (59%) and maximum leg pain on VAS by 48.1 mm (65%). Back pain VAS scores improved from 54.1 by an average of 28.5 points (53%). There was one postoperative wound infection (2.4%) and an overall reoperation rate of 12%. Eighty-two percent patients available for 24 months follow-up with a PTB in situ had a reduction in ODI of greater than 15 points and 74% had a reduction in maximum leg pain VAS of greater than 20 mm. According to Odom criteria, most of these patients (82%) had an excellent or good outcome with all except one patient satisfied with surgery. As measured by the independent core laboratory, there was no significant increase in spondylolisthesis, segmental flexion-extension range of motion, or translation and no loss of lordosis in the patients with PTB at the 2 years follow-up. CONCLUSIONS: Patients with degenerative spondylolisthesis and spinal stenosis treated with decompression and PTB demonstrated no progressive instability at 2 years follow-up. Excellent/good outcomes and significant improvements in patient-reported pain and disability scores were still observed at 2 years, with no evidence of implant failure or migration. Further study of this treatment method is warranted to validate these findings.