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Wolf O. Luedemann, Marcos S. Tatagiba, Sami Hussein and Madjid Samii

✓ The authors report the case of a 27-year-old woman with an arthrogryposis multiplex congenita (AMC) associated with atlantoaxial subluxation. To the authors' knowledge, this is the first report of its kind. The authors review the literature with reference to dysraphic abnormalities associated with atlantoaxial subluxation and with AMC. The patient presented with severe tetraparesis following a minor traffic accident. She underwent a procedure in which transoral decompression and dorsal stabilization were performed and, postoperatively, made a good clinical outcome. The authors stress the need for diagnostic neuroimaging of the craniocervical junction in patients with AMC.

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Steffen K. Rosahl, Alireza Gharabaghi, Peter-Michael Zink and Madjid Samii

Object. Both C-reactive protein (CRP) level and erythrocyte sedimentation rate (ESR) were measured prospectively in 51 cases in which uncomplicated cervical anterior fusion was performed. The object of the authors was to quantify the differences in the responses of these parameters recorded in the immediate postoperative period and to determine factors influencing their course.

Methods. Nineteen one-level, 23 two-level, and nine three-level procedures for disc herniation and degenerative disease of the cervical spine were performed in 22 female and 29 male patients (mean age 49.2 years).

Blood samples were obtained 1 day before as well as on 10 consecutive days and 3 months following anterior cervical fusion. Serum CRP level was measured using a fluorescence polarization immunoassay and ESR was determined from the same samples. Operative time, the number of blood transfusions, and drugs administered in the postoperative period were recorded. In addition, hemoglobin, hematocrit, red blood cell count, platelet count, white cell count, and axillary body temperature were checked daily.

Conclusions. Monitoring of CRP level is superior to that of ESR for early detection of infections after cervical spine surgery. Although CRP was not related to any of the factors that have been proposed to explain its peak value variance in previous studies, individual acute-phase protein metabolism response to tissue affection appears to be a more decisive element in this respect.

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Petra M. Klinge, Georg Berding, Thomas Brinker, Wolfram H. Knapp and Madjid Samii

Object

In this study the authors use positron emission tomography (PET) to investigate cerebral blood flow (CBF) and cerebrovascular reserve (CVR) in chronic hydrocephalus.

Methods

Ten patients whose mean age was 67 ± 10 years (mean ± standard deviation [SD]) were compared with 10 healthy volunteers who were 25 ±3 years of age. Global CBF and CVR were determined using 15O–H2O and PET prior to shunt placement and 7 days and 7 months thereafter. The CVR was measured using 1 g acetazolamide. Neurological status was assessed based on a score assigned according to the methods of Stein and Langfitt.

Seven months after shunt placement, five patients showed clinical improvement (Group A) and five did not (Group B). The average global CBF before shunt deployment was significantly reduced in comparison with the control group (40 ± 8 compared with 61 ± 7 ml/100 ml/minute; mean ± SD, p < 0.01). In Group A the CBF values were significantly lower than in Group B (36 ± 7 compared with 44 ± 8 ml/100 ml/minute; p < 0.05). The CVR before surgery, however, was not significantly different between groups (Group A = 43 ± 21%, Group B = 37 ± 29%). After shunt placement, there was an increase in the CVR in Group A to 52 ± 37% after 7 days and to 68 ± 47% after 7 months (p < 0.05), whereas in Group B the CVR decreased to 14 ± 18% (p < 0.05) after 7 days and returned to the preoperative level (39 ± 6%) 7 months after shunt placement.

Conclusions

The preliminary results indicate that a reduced baseline CBF before surgery does not indicate a poor prognosis. Baseline CBF before shunt placement and preoperative CVR are not predictive of clinical outcome. A decrease in the CVR early after shunt placement, however, is related to poor late clinical outcome, whereas early improvement in the CVR after shunt placement indicates a good prognosis.

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Madjid Samii, Marcos Tatagiba and Gustavo A. Carvalho

Object. The goal of this study was to determine whether some petroclival tumors can be safely and efficiently treated using a modified retrosigmoid petrosal approach that is called the retrosigmoid intradural suprameatal approach (RISA).

Methods. The RISA was introduced in 1983, and since that time 12 patients harboring petroclival meningiomas have been treated using this technique. The RISA includes a retrosigmoid craniotomy and drilling of the suprameatus petrous bone, which is located above and anterior to the internal auditory meatus, thus providing access to Meckel's cave and the middle fossa.

Radical tumor resection (Simpson Grade I or II) was achieved in nine (75%) of the 12 patients. Two patients underwent subtotal resection (Simpson Grade III), and one patient underwent complete resection of tumor at the posterior fossa with subtotal resection at the middle fossa. There were no deaths or severe complications in this series; all patients did well postoperatively, being independent at the time of their last follow-up examinations (mean 5.6 years). Neurological deficits included facial paresis in one patient and worsening of hearing in two patients.

Conclusions. Theapproach described here is a useful modification of the retrosigmoid approach, which allows resection of large petroclival tumors without the need for supratentorial craniotomies. Although technically meticulous, this approach is not time-consuming; it is safe and can produce good results. This is the first report on the use of this approach for petroclival meningiomas.

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Roger Breyer, Sami Hussein, Dorel L. Radu, Klaus-Martin Pütz, Sven Gunia, Hartmut Hecker, Madjid Samii, Gerhard F. Walter and Alexandru C. Stan

Object. Glioblastoma multiforme (GBM) invasiveness is a complex process that involves recognition and attachment of GBM cells to particular extracellular matrix (ECM) molecules before migrating into proteolytically modified matrix and inducing angiogenesis. The CD44 molecule, which is a transmembrane adhesion molecule found on a wide variety of cells including GBM, has been suggested as the principal mediator of migration and invasion. The aim of the present study was to demonstrate whether an antibody specific to the standard form of CD44 (CD44s, 85–90 kD) might prevent invasion and thus disrupt progression of C6 GBM in vivo.

Methods. Immunostaining demonstrated homogeneous expression of CD44s on the surface of C6 GBM cells and tumors. Flow cytometric analysis demonstrated binding saturation of anti-CD44s monoclonal antibody (mAb) to the receptor at 1 µg/5 × 105 cells. Blocking of CD44s in vitro resulted in a dose-dependent progressive (up to 94 ± 2.7%; mean ± standard deviation [SD]) detachment of C6 cells from ECM-coated culture. Blocking of CD44s in vivo resulted in significantly reduced C6 brain tumors (3.6 ± 0.4% [SD])—measured as the quotient: tumor surface (mm2)/brain surface (mm2) × 100—compared with untreated (19.9 ± 0.9%) or sham-treated (19.2 ± 1.1 to 19.3 ± 2.5% [SD]) rats. Disruption of C6 GBM progression correlated with an improved food intake; treated rats were significantly less cachectic (166.6 ± 16.4 g [SD]) than those that were untreated (83 ± 2.7 g [SD]) or sham-treated (83.4 ± 1.1 to 83 ± 2.2 g [SD]) rats.

Conclusions. The authors conclude that CD44s-targeted treatment with specific mAb may represent an effective means for preventing progression of highly invasive GBMs.

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Madjid Samii, Marcos Tatagiba and Gustavo A. Carvalho

Object

The goal of this study was to determine whether some petroclival tumors can be safely and efficiently treated using a modified retrosigmoid petrosal approach that is called the retrosigmoid intradural suprameatal approach (RISA).

Methods

The RISA was introduced in 1983, and since that time 12 patients harboring petroclival meningiomas have been treated using this technique. The RISA includes a retrosigmoid craniotomy and drilling of the suprameatus petrous bone, which is located above and anterior to the internal auditory meatus, thus providing access to Meckel's cave and the middle fossa.

Radical tumor resection (Simpson Grade I or II) was achieved in nine (75%) of the 12 patients. Two patients underwent subtotal resection (Simpson Grade III), and one patient underwent complete resection of tumor at the posterior fossa with subtotal resection at the middle fossa. There were no deaths or severe complications in this series; all patients did well postoperatively, being independent at the time of their last follow-up examinations (mean 5.6 years). Neurological deficits included facial paresis in one patient and worsening of hearing in two patients.

Conclusions

The approach described here is a useful modification of the retrosigmoid approach, which allows resection of large petroclival tumors without the need for supratentorial craniotomies. Although technically meticulous, this approach is not time consuming; it is safe and can produce good results. This is the first report on the use of this approach for petroclival meningiomas.

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Petra M. Klinge, Heike Beck, Thomas Brinker, Gerhard F. Walter and Madjid Samii

Object. Investigation into a potential treatment for the acute period following onset of spontaneous subarachnoid hemorrhage (SAH) is hampered by the lack of a standardized experimental model. For that purpose the authors elaborated on a small-animal model in which computer-controlled intracisternal blood infusion is used and investigated whether this model can reliably reproduce acute neuronal injury after SAH.

Methods. Whole autologous blood (blood-infused group) or isotonic saline (control group) was infused into the cisterna magna or olfactory cistern of rats. The infusions decreased exponentially during a 5-minute period. Throughout the infusion period, intracranial pressure (ICP) was monitored. Neuronal injury was quantified by observing tissue immunoreactivity to a 70-kD heat shock protein (HSP70) and comparing this with the tissue's reaction to hematoxylin and eosin staining. On Days 1, 3, and 5, the CA1, CA3, and dentate gyrus regions of the hippocampus were analyzed, respectively.

During saline infusion ICP increased within seconds beyond 80 mm Hg and afterward decreased in accordance with the infusion rate. During the infusion of blood, the same initial pressure peak was found, but the ICP remained increased beyond this pressure level throughout the 5-minute infusion period. The HSP70 immunoreactivity in the saline-infused group was found only on Day 1 in the CA1 region and the dentate gyrus, but not in the CA3. After injection of whole blood, there was HSP70-positive staining in the CA1, CA3, and dentate gyrus regions throughout the observation period.

Conclusions. The controlled cisternal infusion of blood caused neuronal injury that resembled that of previous experimental models that produce SAH by rupture of intracranial vessels with endovascular techniques. Unlike those experiments, the intracisternal infusion technique presented by the authors provides more standardized bleeding with regard to ICP, the volume of subarachnoid blood, and the extent of acute cellular injury.