Biomedical subjects

Uwe Spetzger

Publications and source records attributed to Uwe Spetzger.

10 recordsLinked to original sources

PubMed2004

Neuronavigation-assisted cranial reconstruction.

OBJECTIVE: Cranial defects resulting from congenital deformities, ablative resection of osseous tumors, traumatic injury, and destructive infectious lesions are often severe enough to warrant surgical reconstruction. In particular cases, satisfactory cosmetic results may be difficult to achieve because of the extent and location of the lesion. METHODS: We evaluated the role of neuronavigation for reconstruction of large cranial defects with prefabricated titanium and intraoperatively constructed neuronavigation-assisted polymethylmethacrylate implants. RESULTS: Neuronavigation-assisted cranial reconstruction was performed in 14 patients. Surgical procedure, illustrative cases, postoperative results, and apparent benefits of the technique are presented and discussed. In all patients, excellent cosmetic results were achieved. CONCLUSION: In cranial reconstruction, neuronavigation is of value not only for intraoperative determination of resection margins but also for preoperative assessment and planning. The combination of navigation techniques with prefabricated or intraoperatively constructed implants enables achievement of excellent cosmetic results.

Adult↗

PubMed2004

Navigation as a tool to visualize bone-covered hidden structures in transfrontal approaches.

A retrospective analysis of 10 patients was performed to evaluate navigation systems in extranasal frontal skull base surgery. When performing a craniotomy following a bicoronal skin incision, the surgeon has to calculate the extent of the frontal sinus to avoid unnecessary damage to the dura or mucoceles later. Due to surgical morbidity including compression of the frontal lobe, many skull base surgeons have refused to use such an approach. Malformation or bone-destruction complicates the identification of the borders and increases the risk of side-effects. Navigation systems can be an alternative for calculating the frontal sinus outlines during surgery. In the authors' surgical procedure two different navigation systems were used. Conventional surgery using the transfrontal, transbasal or subcranial approach consisting of trepanation and craniotomy were performed, while the navigated surgical procedure was evaluated. The analysis showed that computer-assisted surgery (CAS) is applicable to extranasal frontal skull base surgery. In comparison to X-ray beam-controlled craniotomy, CAS is beneficial as it constitutes a noninvasive instrument of quality management. Furthermore, the analysis indicated that under the guidance of a navigation system a precise pre-surgical simulation is available in order to perform an optimal craniotomy and reconstruction of the frontal skull base.

Adult↗

PubMed2003

Preoperative mapping of cortical language areas in adult brain tumour patients using PET and individual non-normalised SPM analyses.

In patients scheduled for the resection of perisylvian brain tumours, knowledge of the cortical topography of language functions is crucial in order to avoid neurological deficits. We investigated the applicability of statistical parametric mapping (SPM) without stereotactic normalisation for individual preoperative language function brain mapping using positron emission tomography (PET). Seven right-handed adult patients with left-sided brain tumours (six frontal and one temporal) underwent 12 oxygen-15 labelled water PET scans during overt verb generation and rest. Individual activation maps were calculated for P<0.005 and P<0.001 without anatomical normalisation and overlaid onto the individuals' magnetic resonance images for preoperative planning. Activations corresponding to Broca's and Wernicke's areas were found in five and six cases, respectively, for P<0.005 and in three and six cases, respectively, for P<0.001. One patient with a glioma located in the classical Broca's area without aphasic symptoms presented an activation of the adjacent inferior frontal cortex and of a right-sided area homologous to Broca's area. Four additional patients with left frontal tumours also presented activations of the right-sided Broca's homologue; two of these showed aphasic symptoms and two only a weak or no activation of Broca's area. Other frequently observed activations included bilaterally the superior temporal gyri, prefrontal cortices, anterior insulae, motor areas and the cerebellum. The middle and inferior temporal gyri were activated predominantly on the left. An SPM group analysis ( P<0.05, corrected) in patients with left frontal tumours confirmed the activation pattern shown by the individual analyses. We conclude that SPM analyses without stereotactic normalisation offer a promising alternative for analysing individual preoperative language function brain mapping studies. The observed right frontal activations agree with proposed reorganisation processes, but they may also reflect an unspecific recruitment of the right-sided Broca's homologue in the effort to perform the task.

Adult↗

PubMed2003

Navigated transoral approach to the cranial base and the craniocervical junction: technical note.

OBJECTIVE: The transoral approach is an elegant reliable surgical procedure that provides anterior exposure of the cranial base and the craniocervical junction. Our objective was to demonstrate the advantages of neuronavigation in planning and performing the transoral approach. METHODS: Three patients with chordomas and one patient with rheumatoid atlantoaxial subluxation were considered for a neuronavigated transoral procedure. For image guidance, the Stryker navigation system (Stryker Instruments, Kalamazoo, MI) was used. Registration was performed with individually constructed occlusal splints with four markers. RESULTS: The transoral approach was successfully used for two patients with chordomas involving the cranial base and the upper spine and for one patient with dislocation of the dens and medullary compression. In one case, preoperative simulation of the approach and trajectory planning demonstrated that adequate resection could not be achieved via the transoral route, and a paracondylar suboccipital approach was used. The registration accuracy achieved with the occlusal splint was less than 1 mm. CONCLUSION: Neuronavigation is a useful tool for planning and performing a transoral approach. It optimizes preoperative planning, clarifies and secures resection limits, and reduces overall surgical morbidity. Registration with an occlusal splint with four markers proved to be an attractive alternative to conventional systems.

Adult↗

PubMed2003

Transvenous treatment of carotid cavernous and dural arteriovenous fistulae: results for 31 patients and review of the literature.

OBJECTIVE: To evaluate findings for patients with carotid cavernous fistulae or dural arteriovenous fistulae (AVFs) who underwent transvenous embolization via different transvenous approaches. METHODS: Retrospective analysis of data for 31 patients (age range, 17-81 yr; mean age, 59.3 yr) with carotid cavernous fistulae (n = 6) or dural AVFs (cavernous sinus [CS], n = 11; transverse/sigmoid sinus, n = 14) was performed. The AVFs were treated with coils via different transvenous approaches, in 56 procedures. Doppler ultrasonography and time-resolved, two-dimensional, magnetic resonance projection angiography were performed to confirm the treatment. The mean clinical follow-up period was 32.5 months. RESULTS: A total of 34 transvenous procedures were performed for 17 AVFs of the CS. Eleven patients with AVFs of the CS (63%) were cured with respect to clinical symptoms, and six patients experienced improvement (37%). The approach via the internal jugular vein and inferior petrosal sinus (n = 15) was possible in 60% of cases, with complete occlusion of the fistula in 78% of cases. With the approach via the facial vein (n = 8), there was a 50% success rate. The superior ophthalmic vein approach (n = 5) was associated with a high rate of technical success (100%), with a rate of complete fistula occlusion of 80%. We encountered complications, with transient morbidity, in four cases (23.5%). For 14 dural AVFs of the transverse/sigmoid sinus, 22 transvenous procedures were performed; 12 patients were cured (85.7%) and 2 experienced improvement (14.3%). The technical success rate was 86%, with complete occlusion in 42% of cases. Minor complications occurred in six cases (42.9%) but did not lead to permanent morbidity. CONCLUSION: Transvenous treatment of CS and transverse/sigmoid sinus AVFs can be effective if all transvenous approaches, including combined surgical/endovascular approaches, are considered.

Adolescent↗

PubMed2002

Indications for and benefits of lumbar facet joint block: analysis of 230 consecutive patients.

OBJECT: The authors evaluated the effectiveness of using a facet joint block with local anesthetic agents and or steroid medication for the treatment of low-back pain in a medium-sized series of patients. METHODS: Over a period of 4 years, the authors performed 715 facet joint injections in 230 patients with variable-length histories of low-back pain. The main parameter for the success or failure of this treatment was the relief of the pain. For the first injection--mainly a diagnostic procedure--the authors used a local anesthetic (1 ml bupivacaine 1%). In cases of good response, betamethasone was injected in a second session to achieve a longer-lasting effect. Long-lasting relief of the low-back pain and/or leg pain was reported by 43 patients (18.7%) during a mean followup period of 10 months. Thirty-five patients (15.2%) noticed a general improvement in their pain. Twenty-seven patients (11.7%) reported relief of low-back pain but not leg pain. Nine patients (3.9%) suffered no back pain but still leg pain. One hundred sixteen patients (50.4%), however, experienced no improvement of pain at all. In two cases the procedure had to be interrupted because of severe pain. There were no cases of infection or hematoma. CONCLUSIONS: Lumbar facet joint block is a minimally invasive procedure to differentiate between facet joint pain and other causes of lower-back pain. The procedure seems to be useful for distinguishing between facet joint pain from postoperative pain due to inappropriate neural decompression after lumbar surgery. It can be also recommended as a possible midterm intervention for chronic low-back pain.

Adult↗

PubMed2002

Malignant germ cell tumors metastatic to the brain: a model for a curable neoplasm? The Freiburg experience and a review of the literature.

The aim of this study on malignant germ cell tumors metastasizing to the brain is (a) to report our institutional experience, (b) to present three patients surviving for more than seven years, and (c) to review the literature with regard to long-term survival. From 1985 to 2000, 916 consecutive patients were treated with whole brain radiation therapy for brain metastases at our hospital. Eleven patients had cerebral lesions from histologically proven malignant germ cell tumors. Brain metastases were diagnosed at presentation (n = 2), following complete remission (n = 3), or along with extracerebral tumor progression (n = 6). Seven patients had a single brain metastasis. Three patients underwent resection. Eight patients reached the planned total dose of 50 Gy. Eight patients had chemotherapy. Median survival was 6.6 months. The long-term survivors all had an isolated cerebral relapse after complete remission, presented with a single brain metastasis, and were treated with resection and whole brain radiation therapy to a total dose of 50 Gy. The first patient died from a late relapse 89 months after the diagnosis of brain metastasis, the second patient is well and alive at 95 months. The third patient is currently being treated for a second malignancy originating from the lung. He is alive at 194 months, the longest survival for brain metastases from malignant germ cell tumors ever reported. Altogether, our study demonstrates that advanced extracerebral disease at initial diagnosis and isolated cerebral relapse after complete remission do not preclude long-term survival. Resection and whole brain radiation therapy might result in durable cerebral control with minimal morbidity.

Adolescent↗

PubMed2002

Comparison of three-dimensional rotational angiography with digital subtraction angiography in the assessment of ruptured cerebral aneurysms.

BACKGROUND AND PURPOSE: Rotational angiography (RA) and digital subtraction angiography (DSA) together may depict more intracranial aneurysms than DSA alone. We compared the diagnostic value of 3D RA and biplanar DSA in detecting, classifying, and planning treatment for ruptured intracranial aneurysms. METHODS: A total of 53 patients with acute subarachnoid hemorrhage (Hunt and Hess grades I-V) underwent angiography with both methods. DSA was performed in two to six standard projections in every vascular territory. Three-dimensional RA datasets were evaluated by using surface-shaded display and maximum intensity projection. The usefulness of DSA images and 3D datasets in detecting aneurysms (number, configuration) and treatment planning were retrospectively analyzed in a blinded manner. RESULTS: In 42 patients, 56 aneurysms were detected, (one to five per patient; size, 0.6-20.4 mm); no aneurysm was found in 11 patients. RA revealed seven aneurysms not seen at conventional DSA. RA failed to depict one aneurysm visible only in a compression series. Delineation of the aneurysmal neck improved with RA in 71% of cases; the parent vessel and its relationship to adjacent vessels was demonstrated better with RA than with DSA in 45% and 50%, respectively. Endovascular treatment was proposed in nine patients; microsurgical therapy, in 26. In seven patients, both options were rated as being equal. Actual treatment consisted of eight endovascular procedures and 30 neurosurgical operations. Four patients died before therapy. CONCLUSION: Compared with DSA, 3D RA allows more exact depiction of anatomic details that are important in planning surgery and interventional therapy for intracranial aneurysms. RA depicted more aneurysms.

Adult↗

PubMedDate not supplied

Carotid cavernous fistula: embolization via a bilateral superior ophthalmic vein approach.

We report the case of a 74-year-old woman with a complex indirect (Barrow D) carotid cavernous sinus fistula. The patient was treated incrementally and finally cured by a rarely reported bilateral retrograde direct transvenous approach via the superior ophthalmic vein. The treatment of the complex carotid cavernous fistula with multiple bilateral fistula points showed additional complexity due to a partially thrombosed left superior ophthalmic vein, which required a combined microsurgical and endovascular treatment, showing that treatment can be achieved, if necessary, by catheterization of a thrombosed orbital vein.

Aged↗

PubMedDate not supplied

Active bleeding from ruptured cerebral aneurysms during diagnostic angiography: emergency treatment.

Despite new developments in the treatment of cerebral aneurysms, recurrent hemorrhage of an aneurysm is the most feared complication of subarachnoid bleeding. The prognosis of patients with early reruptured aneurysms is discouraging. A rerupture of an aneurysm with active bleeding is extremely rare, and the mechanisms involved remain unclear. We report the management of active bleeding of reruptured aneurysms during diagnostic angiography. In two patients, emergency treatment of the active hemorrhage was performed by means of neurosurgical intervention and by an endovascular approach in one other case. The causes and management of reruptured aneurysms with active bleeding are also discussed within the context of a review of the literature.

Adult↗