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ABSTRACT: Neuro-endocrine deficiencies have been argued to be common sequelae after aneurysmal subarachnoid hemorrhage (aSAH). As this, however, does not resemble our clinical experience, we studied the incidence of neuro-endocrine and neuropsychological deficits after aSAH. Twenty-six patients (20 females) were prospectively screened for neuro-endocrine and neuropsychological deficits 3, 6 and 12 months after aSAH. GH, IGF-1, prolactin, LH, FSH, estradiol, testosterone, ACTH as well as cortisol during ACTH-stimulation were assessed. Neuropsychological analysis covered verbal comprehension, short term and working memory, visuospatial construction, figural memory, psychomotor speed, attention, and concentration. During the study period 5 individuals demonstrated neuro-endocrine dysfunction. Hypogonadotrophic hypogonadism resolved spontaneously in 2 patients and central hypothyroidism in one of these patients during the study. After 12 months three patients presented low IGF-1 levels. 73.9% of our cohort was affected by neuropsychological deficits during follow-up. At 3, 6 and 12 months the prevalences were 56.5, 52.6 and 42.1%, respectively. Interestingly, all patients with neuro-endocrine dysfunction presented impaired clinical outcome with a GOS 4 at some time point of the study (GOS 4 vs. 5, 45.5% vs. 0, P = 0.007). We found a low prevalence of neuro-endocrine and a high prevalence of neuropsychological deficits in patients 3, 6 and 12 months after aSAH without significant interrelation. Spontaneous recovery of neuro-endocrine alterations most likely presents an adaption to or dysfunction after severe illness. This hypothesis is strengthened by the fact that only patients with inferior clinical outcome after aSAH as assessed by GOS demonstrated neuro-endocrine dysfunction.
Pituitary 10/2011; · 1.83 Impact Factor
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ABSTRACT: The kinetics of Ga-68-BZH3, a Ga-68-bombesin analog, was compared to molecular biological data obtained from gene arrays in seven patients with a recurrent glioma. The primary aim of this study was the correlation of receptor expression and tracer kinetics.
Dynamic positron emission tomography studies were performed and the data were analyzed by a volume-of-interest technique using a two-tissue compartment model as well as a non-compartment model. Gene array data were obtained from gene array analysis of tumor tissue samples.
The correlation analysis revealed a significant nonlinear correlation of r = 0.89 (p < 0.03) for k1 and BB(2) (gastrin-releasing peptide receptor). BB(1) and BB(3) were not significantly correlated with k1. vb and k3 were not significantly correlated with the expression data of the receptors on the p < 0.05 level.
The parameter k1 is correlated with the expression of BB(2) based on gene array data. The quantitative analysis of the Ga-68-BZH3 kinetics can be used to predict the receptor expression of BB(2) in gliomas based on k1 of the compartment analysis. However, this study is limited to the expression data on the mRNA level and further studies are needed to assess the correlation of gene expression on the protein level.
Molecular imaging and biology: MIB: the official publication of the Academy of Molecular Imaging 07/2011; 14(3):376-83. · 2.47 Impact Factor
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Genevieve Schindler,
David Capper,
Jochen Meyer,
Wibke Janzarik,
Heymut Omran,
Christel Herold-Mende, Kirsten Schmieder,
Pieter Wesseling,
Christian Mawrin,
Martin Hasselblatt,
David N Louis,
Andrey Korshunov,
Stefan Pfister,
Christian Hartmann,
Werner Paulus,
Guido Reifenberger,
Andreas von Deimling
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ABSTRACT: Missense mutations of the V600E type constitute the vast majority of tumor-associated somatic alterations in the v-RAF murine sarcoma viral oncogene homolog B1 (BRAF) gene. Initially described in melanoma, colon and papillary thyroid carcinoma, these alterations have also been observed in primary nervous system tumors albeit at a low frequency. We analyzed exon 15 of BRAF spanning the V600 locus by direct sequencing in 1,320 adult and pediatric tumors of the nervous system including various types of glial, embryonal, neuronal and glioneuronal, meningeal, adenohypophyseal/sellar, and peripheral nervous system tumors. A total of 96 BRAF mutations were detected; 93 of the V600E type and 3 cases with a three base pair insertion between codons 599 and 600. The highest frequencies of BRAF (V600E) mutations were found in WHO grade II pleomorphic xanthoastrocytomas (42/64; 66%) and pleomorphic xanthoastrocytomas with anaplasia (15/23; 65%), as well as WHO grade I gangliogliomas (14/77; 18%), WHO grade III anaplastic gangliogliomas (3/6) and pilocytic astrocytomas (9/97; 9%). In pilocytic astrocytomas BRAF (V600E) mutation was strongly associated with extra-cerebellar location (p = 0.009) and was most frequent in diencephalic tumors (4/12; 33%). Glioblastomas and other gliomas were characterized by a low frequency or absence of mutations. No mutations were detected in non-glial tumors, including embryonal tumors, meningiomas, nerve sheath tumors and pituitary adenomas. The high mutation frequencies in pleomorphic xanthoastrocytomas, gangliogliomas and extra-cerebellar pilocytic astrocytomas implicate BRAF (V600E) mutation as a valuable diagnostic marker for these rare tumor entities. Future clinical trials should address whether BRAF (V600E) mutant brain tumor patients will benefit from BRAF (V600E)-directed targeted therapies.
Acta Neuropathologica 03/2011; 121(3):397-405. · 9.32 Impact Factor
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ABSTRACT: The object of this study was to characterize the regenerative potential of cells isolated from herniated disc tissue obtained during microdiscectomy. The acquired data could help to evaluate the feasibility of these cells for autologous disc cell transplantation.
From each of 5 patients (mean age 45 years), tissue from the nucleus pulposus compartment as well as from herniated disc was obtained separately during microdiscectomy of symptomatic herniated lumbar discs. Cells were isolated, and in vitro cell expansion for cells from herniated disc tissue was accomplished using human serum and fibroblast growth factor-2. For 3D culture, expanded cells were loaded in a fibrin-hyaluronan solution on polyglycolic acid scaffolds for 2 weeks. The formation of disc tissue was documented by histological staining of the extracellular matrix as well as by gene expression analysis of typical disc marker genes.
Cells isolated from herniated disc tissue showed significant signs of dedifferentiation and degeneration in comparison with cells from tissue of the nucleus compartment. With in vitro cell expansion, further dedifferentiation with distinct suppression of major matrix molecules, such as aggrecan and Type II collagen, was observed. Unlike in previous reports of cells from the nucleus compartment, the cells from herniated disc tissue showed only a weak redifferentiation process in 3D culture. However, propidium iodide/fluorescein diacetate staining documented that 3D assembly of these cells in polyglycolic acid scaffolds allows prolonged culture and high viability.
Study results suggested a very limited regenerative potential for cells harvested from herniated disc tissue. Further research on 2 major aspects in patient selection is suggested before conducting reasonable clinical trials in this matter: 1) diagnostic strategies to predict the regenerative potential of harvested cells at a radiological or cell biology level, and 2) clinical assessment strategies to elucidate the metabolic state of the targeted disc.
Journal of neurosurgery. Spine 02/2011; 14(2):273-80. · 1.61 Impact Factor
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ABSTRACT: This is an illustration of two case reports.
We present two cases where intradural indocyanine-green (ICG) videography facilitated interpretation of vascular supply patterns and anatomic landmarks in intramedullary spinal lesions.
ICG videography is a new, complimentary imaging method, that is routinely employed in the context of vascular neurosurgical procedures and has recently been described to facilitate localization of intradural spinal lesions before dural opening. Its role in the setting of intramedullary lesions is less well defined.
Two cases are presented. The first patient (case 1) had a small, diffuse, intramedullary lesion of unknown etiology who was referred for additional work-up and surgery. The second patient had presented with progressive paraparesis and ataxia due to an extensive intradural lesion, and he was referred for resection of the tumor.Routine exposure of the spinal cord via (hemi-)laminectomy and durotomy was followed by ICG videography (injection of intravenous indocyanine green, visualization with operating microscope in combination with an additional fluorescent light source) to guide the surgical strategy.
In case 1, ICG videography helped to delineate the anatomic midline for optimization of myelotomy. In case 2, imaging was able to identify arterial feeders of the highly vascularized lesion and simplified safe removal of the lesion.
ICG videography may represent a useful adjunct for optimization of surgical approach and strategy in intramedullary spinal tumors in selected cases. The anatomic midline can be safely identified in cases where usual landmarks are distorted, and better interpretation of supply patterns in highly vascularized lesions may increase safety of resection.
Spine 02/2011; 36(12):E811-3. · 2.08 Impact Factor
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ABSTRACT: Dynamic PET studies with a ⁶⁸Ga-Bombesin analog, the ⁶⁸Ga-BZH₃, were performed in patients with highly suspected recurrent gliomas to investigate the effect of the receptor scintigraphy on tumor grading. Furthermore, dynamic F-18 Fluorodeoxyglucose (FDG) studies were performed for comparison.
The study consisted of 15 patients with histologically confirmed recurrent gliomas. Dynamic PET scans using ⁶⁸Ga-BZH₃ and FDG were obtained on 2 different days within 1 week. Multivariate analysis was used for the evaluation of the kinetic data. Standardized uptake values were calculated and a compartment (2-tissue) as well as a noncompartment model was used for data evaluation of both tracers.
The evaluation includes 6 patients with a WHO II, 6 patients with a WHO III, and 3 patients with a WHO IV recurrent gliomas. Of the 15 patients, 10 patients demonstrated an increased ⁶⁸Ga-BZH₃ uptake visually, 3 of them with a WHO II, 4 with a WHO III, and 3 with a WHO IV tumor. Of the 15 patients, 6 patients revealed an enhanced FDG metabolism visually, 3 of them with a WHO II, and 3 with a WHO III. None of the 3 patients with WHO IV tumor demonstrated an enhanced FDG-uptake. Discriminant analysis based on a combination of FDG influx and binding potential of ⁶⁸Ga-BZH₃ best discriminated between low- and high-grade gliomas with a correct classification rate of 100%.
⁶⁸Ga-BZH₃ seems to be helpful in patients with recurrent gliomas for the differentiation between low- and high-grade gliomas. Overall, the quantitative evaluation was superior to the visual analysis and the parameters of the ⁶⁸Ga-BZH₃ kinetics were more helpful than those of FDG for the differentiation between low- and high-grade gliomas.
Clinical nuclear medicine 02/2011; 36(2):101-8. · 3.92 Impact Factor
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ABSTRACT: Human annulus fibrosus tissue and cells were analyzed for the presence of chemokine receptors and the migratory effect of selected chemokines.
To investigate spontaneous repair mechanisms and underlying cell recruitment in response to annular tears and degenerative defects.
Resorption of herniated disc tissue and the attempt to close annulus tears with repair tissue occur spontaneously. Although chemokines are suggested to play a role in resorption of herniated disc tissue, the role of chemokines in annulus fibrosus homeostasis and repair remains unclear.
Cells were isolated from annulus fibrosus tissue and expanded in the presence of human serum. Multiwell chemotaxis assays were used to analyze the migratory effect of human serum and 0 to 1000 nM concentrations of the chemokines CXCL7, CXCL10, CXCL12, CCL25, and XCL1 on annulus fibrosus cells (AFCs) (n = 9 per chemokine and dose). Presence of corresponding chemokine receptors in AFCs was determined by real-time polymerase chain reaction analysis and immunohistochemistry.
Serum (0.1%-10%) significantly (P < 0.01) stimulates the migration of AFCs. Compared with untreated cells, the migration of cells was significantly (P < 0.01) enhanced upon stimulation with 100 to 1000 nM CXCL10 and 1000 nM XCL1. Chemokine receptors showed low expression levels in expanded AFCs as assessed by polymerase chain reaction. Immunohistochemical staining of the CXCL10 receptor CXCR3 and the XCL1 receptor XCR1 showed that the presence of the particular receptors in AFCs expanded under conventional cell culture conditions. In native annulus fibrosus tissue, CXCR3 was evident, whereas XCR1 could not be detected.
The findings suggest that chemokines, in particular CXCL10, effectively recruit isolated AFCs. This suggests that chemokines are involved in annulus fibrosus homeostasis and potentially in spontaneous annulus repair attempts. This might have important implications for biological annulus-sealing strategies.
Spine 01/2011; 37(2):101-7. · 2.08 Impact Factor
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ABSTRACT: A prospective analysis.
Our aim was to assess the radiographically detectable bony fusion in patients with anterior cervical discectomy (ACD) and polyetheretherketone (PEEK)-cage implantation without additional filling. Furthermore, clinical data of patients with and without fusion were compared.
PEEK-cage implantation is performed in cervical spinal surgery because of its benefits. However, fusion rates without filling of the cage have not been reported.
Patients selected for ACD with PEEK-cage implantation prospectively underwent plain radiography in anterior-posterior and lateral projections during the postoperative hospital stay and at follow-up. Furthermore, clinical status was evaluated using the Odom scale, the Short Form-36, the Visual Analog Scale (VAS) for arm and neck pain, and the cervical Oswestry score. Fusion status, migration, and subsidence of the PEEK cage were evaluated on the basis of the lateral radiographs. Fusion was confirmed by presence of continuous trabecular bone bridges in the disc space. To exclude an influence of the cage on the evaluation of fusion rates, fusion was evaluated in analogous fashion retrospectively in a control group.
A total of 52 patients underwent ACD and interbody fusion. One-level surgery was performed in 44 patients and 2-level surgery in 8 patients. A total of 60 ACD and interbody fusions with a PEEK cage were analyzed. A majority of operations were at the C5/6 level (40 patients, 77%). Cage height was 4 mm in 32 cases, 5 mm in 23 cases, and 6 mm in 5 cases. Bony fusion was present at 43 treated levels (71.7%), whereas at 17 levels (28.3%) no fusion was found. Statistical analysis revealed no significant difference between the fusion and non-fusion groups regarding time to follow-up, implanted cage height. Short Form-36, cervical Oswestry score, VAS arm and neck, or Odom criteria. In the control group, ACD was performed in 29 patients (42 levels; 18 one-level and 12 two-level operations). Bony fusion was present at 30 levels (71.4%), whereas non-fusion was present at 12 treated levels (28.6%). Statistically analysis revealed no significant difference between the study group and the control group regarding time to follow-up or fusion rates.
Implantation of empty PEEK cages after ACD shows an unexpectedly low rate effusion according to radiologic criteria, although no statistically significant difference could be observed clinically.
Spine 01/2011; 36(1):15-20. · 2.08 Impact Factor
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Dennis P Devito,
Leon Kaplan,
Rupert Dietl,
Michael Pfeiffer,
Dale Horne,
Boris Silberstein,
Mitchell Hardenbrook,
George Kiriyanthan,
Yair Barzilay,
Alexander Bruskin, [......],
Gordon D Donald,
Donald G Gordon,
Robert Schoenmayr,
Alon Friedlander,
Nachshon Knoller, Kirsten Schmieder,
Ioannis Pechlivanis,
In-Se Kim,
Bernhard Meyer,
Moshe Shoham
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ABSTRACT: Retrospective, multicenter study of robotically-guided spinal implant insertions. Clinical acceptance of the implants was assessed by intraoperative radiograph, and when available, postoperative computed tomography (CT) scans were used to determine placement accuracy.
To verify the clinical acceptance and accuracy of robotically-guided spinal implants and compare to those of unguided free-hand procedures.
SpineAssist surgical robot has been used to guide implants and guide-wires to predefined locations in the spine. SpineAssist which, to the best of the authors' knowledge, is currently the sole robot providing surgical assistance in positioning tools in the spine, guided over 840 cases in 14 hospitals, between June 2005 and June 2009.
Clinical acceptance of 3271 pedicle screws and guide-wires inserted in 635 reported cases was assessed by intraoperative fluoroscopy, where placement accuracy of 646 pedicle screws inserted in 139 patients was measured using postoperative CT scans.
Screw placements were found to be clinically acceptable in 98% of the cases when intraoperatively assessed by fluoroscopic images. Measurements derived from postoperative CT scans demonstrated that 98.3% of the screws fell within the safe zone, where 89.3% were completely within the pedicle and 9% breached the pedicle by up to 2 mm. The remaining 1.4% of the screws breached between 2 and 4 mm, while only 2 screws (0.3%) deviated by more than 4 mm from the pedicle wall. Neurologic deficits were observed in 4 cases yet, following revisions, no permanent nerve damage was encountered, in contrast to the 0.6% to 5% of neurologic damage reported in the literature.
SpineAssist offers enhanced performance in spinal surgery when compared to free-hand surgeries, by increasing placement accuracy and reducing neurologic risks. In addition, 49% of the cases reported herein used a percutaneous approach, highlighting the contribution of SpineAssist in procedures without anatomic landmarks.
Spine 11/2010; 35(24):2109-15. · 2.08 Impact Factor
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ABSTRACT: The current WHO classification of brain tumors defines gliomatosis cerebri (GC) as an extensively infiltrating astrocytic glioma involving at least three cerebral lobes. The relation of GC to diffuse astrocytomas and glioblastoma is uncertain. Due to malignant biological behavior, GC is allotted to WHO grade III. Recent reports showed IDH1 mutations in astrocytic and oligodendroglial tumors WHO grades II and III and in secondary glioblastomas with a frequency of up to 90%, whereas IDH1 mutations occurred in only 5% of primary glioblastomas. Here, we examined the frequency of IDH1 mutations in 35 GC samples by direct sequencing, derived cleaved amplified polymorphic sequence analysis and immunohistochemistry. We identified IDH1 mutations in 10/24 (42%) cases, which also included a solid tumor portion (type 2 GC), but not in 11 "classical" cases without solid tumor mass (type 1 GC). TP53 mutations were revealed in two type 2 GC, but not in any type 1 GC, while combined chromosomal losses of 1p and 19q were not found at all. Our data suggest that GC consists of two histological/molecular subtypes, type 1 being clearly distinct from diffuse astrocytoma, and type 2 sharing features with diffuse astrocytoma.
Acta Neuropathologica 08/2010; 120(2):261-7. · 9.32 Impact Factor
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ABSTRACT: The authors discuss a rare case of hemorrhage in a filum terminale ependymoma presenting with acute paraparesis and transient hydrocephalic dementia in association with long-term phenprocoumon anticoagulation. The CT scan of the brain revealed the presence of blood in both occipital horns and communicating hydrocephalus. The symptoms gradually resolved after tumor removal and there was no need for shunting. This is a complex clinical presentation of a spinal cord tumor associated hemorrhage, which further illustrates the possibility of retrograde passage of blood from the lumbosacral region to the ventricles.
Clinical neurology and neurosurgery 04/2010; 112(3):252-7. · 1.30 Impact Factor
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ABSTRACT: We present a patient with intractable hiccups. Medical treatment decreased the frequency of the hiccups to only 5-10 per minute. After exclusion of gastrointestinal reasons for the hiccups, cranial MRI revealed a small lesion in the right rhomboid fossa, close to the vagal trigone. Microsurgical resection of the lesion was performed via a suboccipital median craniotomy. The histopathological diagnosis was a cavernoma. Promptly after surgery the patient was free of symptoms. Intractable hiccups can be associated with intracranial pathologies, including lesions in the brain stem, which we highlight with the presentation of this patient.
Journal of Clinical Neuroscience 03/2010; 17(6):781-3. · 1.25 Impact Factor
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ABSTRACT: Glioblastoma multiforme is the most common and most malignant primary brain tumour. Prognosis after diagnosis remains poor despite recent advances in adjuvant therapy. Treatment of choice is gross surgical resection and combined radio-chemotherapy with temozolomide as chemotherapeutic agent. Experimental continuous low-dose chemotherapy with temozolomide in combination with a cyclooxygenase-2 inhibitor has shown encouraging effects on progression-free survival and overall survival in patients, but leads to a high proportion of distant recurrences. Here, we describe extreme far-distant metastases along the neural axis of glioblastoma multiforme in four patients receiving metronomic antiangiogenic chemotherapy and review the literature to discuss possible mechanisms.
Neurosurgical Review 03/2010; 33(3):375-81; discussion 381. · 2.04 Impact Factor
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ABSTRACT: Long-term administration of adjuvant temozolomide is common practice in many institutions, especially when treatment is well tolerated and stable disease is achieved. In this study, we evaluate the feasibility and efficacy of long-term temozolomide in patients with glioblastoma multiforme treated at a single institution.
One hundred and fourteen patients with newly diagnosed glioblastoma were followed for the course of their disease. Treatment consisted of surgery [gross total resection (GTR) subtotal resection (STR) or biopsy] followed by radiotherapy and concomitant temozolomide. Adjuvant temozolomide was administered until evidence for progressive disease or serious side effects occurred. Follow-up was routinely performed every 3 months.
One hundred and fourteen patients with glioblastoma multiforme received a median of 6 cycles of adjuvant first-line temozolomide (range 1-57). For patients with less than 6 cycles, chemotherapy was stopped in 60% for reasons other than progression, while only in 17% of patients receiving 6 or more (P < 0.0001). Median TTP was 7 months (95% CI: 6-10 months). PFS after 6 months was 53%. Median OS in all patients was 15 months (95% CI: 13-18 months). TTP and OS directly correlate with the amount of chemotherapy cycles (each P < 0.0001). No significant influence of the extent of surgical treatment on PFS (P = 0.2141) and OS (P = 0.4308) could be detected.
This data set suggests that long-term administration of temozolomide is safe and efficacious. Side effects occur more frequently in the early phase of drug administration (<6 cycles). There is a strong correlation of long-term temozolomide on PFS and OS regardless of the extent of surgery and other factors.
Journal of Cancer Research and Clinical Oncology 02/2010; 136(11):1691-5. · 2.56 Impact Factor
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ABSTRACT: SCIENTIFIC BACKGROUND: Meningiomas are the most common benign intracranial neoplasms with a slow growth presented as the intracranial lesion. These tumors are without any symptoms for a long time. At the time of diagnosis it is frequently an asymptomatic tumor. In that case the therapist may well suggest a wait-and-see strategy. The therapy of meningiomas focuses firstly on the microsurgical treatment. Volume reduction can be achieved immediately after treatment. Stereotactic radiosurgery is an important non-invasive treatment option for recurrent tumors or meningiomas with partial resection. The technical equipment for the stereotactic radiosurgery is a cost intensive investment. In this context the high precision of the intervention, presented as a low invasiveness of the treatment, is an important factor. The aim of this assessment is to identify the chances and limitations of the diverse treatment options and to estimate their outcome for different localisations of meningiomas.
In December 2007 a systematic literature search was conducted using the most relevant medical databases. The whole strategy and the used search terms were documented. The literature search was supplemented with an internet and literature based hand search on law, ethics and economics. Primary studies and systematic reviews which report relevant outcomes are included in this analysis. The current assessment is based on the available evidence that was found at the time of the literature search.
A total of 31 publications for the medical focus of assessment and three reports from the economical hand search were included. In general, it is not possible to identify neither randomised clinical trials or prospective, contrasting cohort studies nor studies summarising results from such studies. The results presented in the literature published by surgeons strongly vary regarding localisation of meningiomas. Publications not differentiating between the localisation of meningiomas indicate a progression free survival rate of five years in 77 to 97% of the cases after complete surgical resection of the tumor, in 18 to 70% of the cases after subtotal resection and for patients who had undergone surgical resection and a combined radiotherapeutical treatment of their meningiomas a five year progression free survival rate between 82 and 97%. Other treatment options like hormone therapy or treatments to stop tumor growth had been used unsuccessfully so far. Based on the results presented regarding economic evaluation, costs resulting from radiosurgical treatment are lower in contrast to costs resulting from surgical resection. However, it has to be taken into account that costs resulting from radiosurgical treatment strongly depend on the number of patients treated in total with the radiosurgical equipment.
Due to the strong dependencies between the results from surgical therapy and the localisation of the tumor, it is only possible to derive recommendations on whether or not to perform the surgical therapy with respect to the localisation of the tumor. Only for patients with tumors with a spinal localisation or WHO Grade I meningiomas with a cortical localisation, primary treatment with by means of microsurgery can be suggested. For all other localisations of the tumor, alternative treatment by radiosurgery should be discussed. From the literature identified, a clear recommendation of one or the other therapy however can not be deduced. Thus, there is a strong need for randomised clinical trials or prospective or contrasting cohort studies, which compare rigorously microsurgery with radiosurgery concerning different localisations of tumors.
GMS health technology assessment. 01/2010; 6:Doc02.
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ABSTRACT: Because of the implant-related problems with pedicle screw-based spinal instrumentations, other types of fixation have been tried in spinal arthrodesis. One such technique is the direct trans-pedicular, trans-discal screw fixation, pioneered by Grob for spondylolisthesis. The newly developed GO-LIF procedure expands the scope of the Grob technique in several important ways and adds security by means of robotic-assisted navigation. This is the first clinical trial on the GO-LIF procedure and it will assess safety and efficacy.
Multicentric prospective study with n = 40 patients to undergo single level instrumented spinal arthrodesis of the lumbar or the lumbosacral spine, based on a diagnosis of: painful disc degeneration, painful erosive osteochondrosis, segmental instability, recurrent disc herniation, spinal canal stenosis or foraminal stenosis. The primary target criteria with regards to safety are: The number, severity and cause of intra- and perioperative complications. The number of significant penetrations of the cortical layer of the vertebral body by the implant as recognized on postoperative CT. The primary target parameters with regards to feasibility are: Performance of the procedure according to the preoperative plan. The planned follow-up is 12 months and the following scores will be evaluated as secondary target parameters with regards to clinical improvement: VAS back pain, VAS leg pain, Oswestry Disability Index, short form - 12 health questionnaire and the Swiss spinal stenosis questionnaire for patients with spinal claudication. The secondary parameters with regards to construct stability are visible fusion or lack thereof and signs of implant loosening, implant migration or pseudarthrosis on plain and functional radiographs.
This trial will for the first time assess the safety and efficacy of guided oblique lumbar interbody fusion. There is no control group, but the results, the outcome and the rate of any complications will be analyzed on the background of the literature on instrumented spinal fusion. Despite its limitations, we expect that this study will serve as the key step in deciding whether a direct comparative trial with another fusion technique is warranted.
Clinical Trials NCT00810433.
BMC Musculoskeletal Disorders 01/2010; 11:199. · 1.58 Impact Factor
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ABSTRACT: Recent work has demonstrated the accuracy and operational viability of an algorithm proposed by the authors that successfully registers 3-D ultrasound data with CT or MRI data. The successful application of this method to intraoperative navigation, however, depends critically on the quality of the acquired ultrasound data. This gives rise to two questions concerning the usability of the algorithm in clinical praxis. First, how can one guarantee high-quality, user-independent ultrasound registration data with this procedure? Second, can this approach work reliably in clinical practice, namely within the operating theater? To address both of these questions, we present an ultrasound data acquisition protocol that leads the user through the data acquisition process and also provides the criteria to adjust the relevant ultrasound parameters. We also evaluated criteria for the visual inspection of the suitability of the ultrasound data for the registration process. Results for this evaluation show that these visual criteria can be used to decide preoperatively if an ultrasound registration will be successful in a patient. The intraoperative evaluation of the protocol showed that high-quality registrations can be achieved under realistic conditions. This protocol and the visual inspection criteria, together with the ultrasound registration algorithm, provide a surgical team with a means of performing precise, cost-effective navigation in patients for whom a navigated intervention was previously impossible. We evaluated the proposed procedure in clinical practice.
Ultrasound in medicine & biology 09/2009; 35(11):1773-82. · 2.02 Impact Factor
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ABSTRACT: Gliomatosis cerebri is a rare primary cerebral tumour entity characterized by diffuse infiltrative growth patterns representing a WHO grade III malignancy. The prognosis is dismal and therapeutical options are still controversial. In contrast to other high-grade gliomas, angiogenesis is thought to be absent in gliomatosis cerebri.
Despite this assumption, histopathological analyses of samples of six patients with gliomatosis cerebri were performed and surprisingly there was angiogenic activity with expression of vascular endothelial growth factor and cyclooxygenase 2. It was therefore decided to administer continuous low-dose chemotherapy with temozolomide and celecoxib for antiangiogenic treatment in the four patients that were in good clinical condition following external radiotherapy.
In all patients, treatment was well tolerated and MRI follow-up showed no tumour progression for at least six months. One patient died due to pulmonary embolism 9 months after diagnosis; another patient survived 15 months after diagnosis with progressive disease in the last follow-up MRI before death. Two other patients at the present time are still in a stable clinical condition without signs of tumour progression in MRI (12 and 18 months).
From our initial experience in a small number of patients with gliomatosis cerebri with signs of angiogenic activity, we conclude that low-dose chemotherapy might provide a promising approach for treatment of these patients and that overexpression of angiogenic factors such as VEGF or COX-2 seems to be more frequent than hitherto reported.
Anticancer research 09/2009; 29(8):3261-7. · 1.73 Impact Factor
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ABSTRACT: A prospective analysis.
The idea of this study was to evaluate a new miniature robotic system providing passive guidance for pedicle screw placement at the lumbar spine. Special focus was laid on the postoperative accuracy of screw placement.
Recent technical developments lead to a minimization of pedicle screw fixation techniques. However, the use of navigational techniques is still under controversy.
Patients selected for a minimal invasive posterior lumbar interbody fusion received a spiral computer tomographic scan before surgery. The miniature hexapod robot was mounted to the spinous process and the system moves to the exact entry point according to the trajectory of the surgeon's preoperative plan. After minimal invasive screw placement all patients received routinely a postoperative spiral computer tomographic scan. Screws placed exactly within the pedicle were evaluated as group A, screws deviating <2 mm were evaluated as group B, > or =2 mm to <4 mm (group C); > or =4 mm to <6 mm (group D); and more than 6 mm (group E).
Thirty-one patients received a PLIF with percutaneous posterior pedicle screw insertion using the bone mounted miniature robotic device. A total of 133 pedicle screws were placed. The majority of the screws were placed in L5 (58 screws; 43.6%). In axial plane, 91.7% of the screws were evaluated as group A and 6.8% were evaluated as group B. In longitudinal plane, 81.2% of the screws were evaluated as group A and 9.8% were evaluated as group B. In 1 screw (L5 right) the postoperative evaluation was done as group C (axial plane) and D (longitudinal plane). In 29/31 cases the integration of the miniature robotic system was successful.
In our study the first clinical assessment of a new bone mounted robot system guiding percutaneous pedicle screw placement was done. A deviation <2 mm to the surgeon 's plan in 91.0% to 98.5% verifies the system's accuracy.
Spine 02/2009; 34(4):392-8. · 2.08 Impact Factor
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ABSTRACT: The case of a 33-year-old female who suffered from a recurrence of an intrachiasmatic cavernous malformation is presented. She had already undergone surgery in 1991 and 2001 and was admitted to our hospital with reduced vision in the right eye. After MRI, and diagnosis of recurrence of the cavernoma, a neurosurgical operation was performed using the pterional approach. The intraoperative situation was documented with micro photographs. The postoperative course was uneventful. The female described a minimal improvement of her vision. No postoperative complications were observed. To our knowledge, microsurgically complete extirpation of a recurrence of an intrachiasmatic cavernoma has not yet been reported in the literature.
Clinical ophthalmology (Auckland, N.Z.) 01/2009; 2(4):945-9.
