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C Matula

Publications and source records attributed to C Matula.

35 records · Page 2Linked to original sources
PubMed1995

Endoscopically assisted microneurosurgery.

Technological developments in neuroendoscopy are leading to an expansion of applications into the realm of microneurosurgical procedures. The new dimension that using an endoscope provides requires insight into different neuroanatomical aspects and a new kind of strategy in planning a microneurosurgical procedure. To gain some new insights into these exciting aspects of neurosurgery we have explored the sellar, parasellar, and posterior fossa regions in 50 fresh anatomical specimens and used various types of endoscopes to observe the surgically relevant neurotopographical details. We then utilized this experience in 33 clinical cases during microsurgical approaches for various lesions (posterior fossa tumors - 12 cases, sellar and parasellar tumors - 8 cases, trans-sphenoidal procedures for pituitary adenoma - 7 cases, transventricular procedures - 6 cases). In the laboratory we found that familiar neuroanatomical structures are seen in a completely different aspect from what we are accustomed. Orientation is at times difficult, which requires rehearsal and special handling of the endoscope for complex clinical procedures. We found that certain structures that are hardly noticed in routine anatomical views become very important when utilizing the endoscope (i.e., different arachnoid membranes and trabeculae). Importantly, the dimensions of a microsurgical approach can be greatly enlarged with the endoscope, making it possible to look behind structures and ''around corners''. We present our findings with respect to important anatomical details relevant to utilizing the endoscope as an adjunct to microneurosurgical procedures and our clinical data. We have concluded that the neuroendoscope can be a safe and helpful adjunct in many microneurosurgical procedures.

Endoscopy↗
PubMed1995

Detection of tumor necrosis factor-alpha protein and messenger RNA in human glial brain tumors: comparison of immunohistochemistry with in situ hybridization using molecular probes.

Tumor necrosis factor-alpha (TNF alpha) protein and messenger (m)RNA distribution was studied in biopsy samples of glial brain tumors, using immunohistochemistry and in situ hybridization with molecular probes, to investigate the role of this cytokine in tumor proliferation and immunological host defense. Focal expression of TNF alpha was detected in four of four glioblastomas, one of two anaplastic astrocytomas, and four of five low-grade astrocytomas, regardless of their subtype or grade of malignancy, but in none of the normal peritumoral brain tissues used as controls. The TNF alpha protein and mRNA were present in reactive astrocytes and protoplasmic tumor cells, confined to areas of leukocyte or T-lymphocyte infiltrating, and less pronounced in tumor cells at the edge of necrosis. Additionally, TNF alpha reactivity was found in infiltrating macrophages and perivascular microglia. Immunohistochemistry and in situ hybridization for TNF alpha showed comparable reaction patterns and numbers of TNF alpha-positive cells, even though the sensitivity of in situ hybridization was significantly higher. Quantitative evaluation of TNF alpha protein, TNF alpha mRNA, and leukocyte infiltration revealed a significant positive correlation between the TNF alpha-positive reactive astrocytes and the number of lymphocytes present in corresponding areas. Together, these data lead to the conclusion that TNF alpha in reactive astrocytes and monocytic cells within tumor areas of high leukocyte infiltration and in tumor cells at the border of necrosis may represent one defense pathway of the immune system against tumor proliferation.

Adolescent↗
PubMed1994

Magnetic resonance angiography and selective angiography following extra-intracranial bypass operations.

Magnetic resonance angiography (MRA) was compared with conventional angiography in 14 patients following extra-intracranial arterial anastomosis. In 13 patients the bypass was shown by MRA and confirmed by conventional angiography. In five of these, the anastomosed vessels, in particular the superficial temporal artery, was of the same calibre or smaller than the same vessels on the contralateral, healthy side. In one patient no anastomosis could be shown by MRA, and occlusion of the bypass was confirmed by conventional angiography. Absence of dilatation of the anastomotic vessels may indicate insufficient bypass function due to stenosis or an incorrect indication for surgery.

Adult↗
PubMed1994

Growth hormone-prolactin-thyrotropin-secreting pituitary adenoma in atypical McCune-Albright syndrome with functionally normal Gs alpha protein.

The McCune-Albright syndrome (MAS) comprises a triad of physical signs: localized bone lesions termed polyostotic fibrous dysplasia, café-au-lait pigmentation of the skin, and autonomous hyperfunction of multiple endocrine systems, including overproduction of GH and T4. A somatic activating point mutation in the gene for the alpha-subunit of the G-protein (Gs alpha) in the affected tissue has been claimed to be the underlying defect. A 29-yr-old patient with MAS, showing polyostotic fibrous dysplasia associated with acromegalic features, underwent endocrinological studies, including oral glucose tolerance test and pituitary stimulation test, and magnetic resonance imaging, revealing elevated plasma concentrations of GH, PRL, and secondary hyperthyroidism due to pituitary macroadenoma infiltrating the sphenoid cavity and extending to the suprasellar space. Subsequently, reduction of tumor mass by a transsphenoidal and a subsequent subfrontal operation led to only marginal amelioration of the excessive hormone production. Postsurgery octreotide and bromocriptine therapy induced near-normalization of hormone concentrations. Immunohistochemistry of tumor tissue confirmed the plurihormonal character, but DNA sequence analysis did not detect any of the two known activating mutations in the Gs alpha gene. Furthermore, biochemical tests revealed normal Gs alpha function, ruling out other mutations that lead to constitutive Gs alpha activation. Our study documents that MAS is a heterogeneous disease. Some, but clearly not all, patients have oncogenic mutations of the gene coding for Gs alpha. Any gene acting down-stream of Gs can theoretically be predicted to result in the same phenotype. In addition, hyperthyroidism of MAS may be secondary to a TSH-producing pituitary macroadenoma.

Adenoma↗
PubMed1993

Colour Doppler imaging of partial subclavian steal syndrome.

The case of a 67-year-old woman with symptoms related to the vertebro-basilar system and blood pressure difference of the upper extremities is presented. Colour-Doppler imaging (CDI) with additional spectral tracing revealed partial subclavian steal syndrome with retrograde flow in the left vertebral artery during systole, which could be significantly enhanced by reactive hyperemia after left arm exercise. Angiography confirmed a high-grade stenosis of the proximal subclavian artery and balloon angioplasty was performed. Noninvasive follow-up by CDI demonstrated regular antegrade vertebral artery flow at rest, but minimal retrograde systolic flow after left arm exercise.

Aged↗
PubMed1993

Difficulties in examination of the origin of the vertebral artery by duplex and colour-coded Doppler sonography: anatomical considerations.

Despite progress in ultrasonographic techniques visualisation of the origin of the vertebral arteries, particularly the left, by duplex and colour Doppler imaging, still poses a problem in a significant number of patients. In anatomical and radiological studies we demonstrated an anomalous origin in 6%, the left vertebral artery originating directly from the aorta in most cases. The origin from the subclavian artery was found to be posterior in 44% and inferior in 6%. The V1 segment of the vertebral artery (from its origin to the entry into the foramen transversarium) was tortuous in 47% of cases. These anatomical variants and variations in the course of the vessel contribute to the nonvisualisation of the origin of the vertebral artery by duplex and colour Doppler imaging. With respect to tortuosities technical modifications for better visualisation are suggested and possible implications for surgery are discussed.

Aged↗
PubMed1993

Pituitary adenomas with invasion of the cavernous sinus space: a magnetic resonance imaging classification compared with surgical findings.

We present 25 pituitary adenomas that were confirmed surgically to have invaded the cavernous sinus space. The surgical results are compared with the preoperative magnetic resonance imaging findings. For comparable radiological criteria, we classified parasellar growth into five grades. This proposed classification is based on coronal sections of unenhanced and gadolinium diethylene-triamine-pentaacetic acid enhanced magnetic resonance imaging scans, with the readily detectable internal carotid artery serving as the radiological landmark. The anatomical, radiological, and surgical conditions of each grade are considered. Grades 0, 1, 2, and 3 are distinguished from each other by a medial tangent, the intercarotid line--through the cross-sectional centers--and a lateral tangent on the intra- and supracavernous internal carotid arteries. Grade 0 represents the normal condition, and Grade 4 corresponds to the total encasement of the intracavernous carotid artery. According to this classification, surgically proven invasion of the cavernous sinus space was present in all Grade 4 and Grade 3 cases and in all but one of the Grade 2 cases; no invasion was present in Grade 0 and Grade 1 cases. Therefore, the critical area where invasion of the cavernous sinus space becomes very likely and can be proven surgically is located between the intercarotid line and the lateral tangent, which is represented by our Grade 2. We also measured tumor growth rates, using the monoclonal antibody KI-67, which shows a statistically higher proliferation rate (P < 0.001) in adenomas with surgically observed invasion into the cavernous sinus space, as compared with noninvasive adenomas.

Adenoma↗
PubMed1992

[Noninvasive follow-up by color-coded Doppler sonography after surgical interventions on the extracranial cerebral arteries].

By means of colour-coded Doppler sonography we studied retrospectively the incidence of postoperative changes in 54 patients following 58 carotid endarterectomies. The interval between operation and ultrasound varied from one to 41 months. The overall incidence of recurrent carotid disease was 50% with a 31% (18 of 58) of hemodynamically insignificant restenoses, a 13.8% (8 of 58) incidence of haemodynamically significant restenoses, and a 5.2% (3 of 58) of occlusions. The segment that had been endarterectomized showed a bulbous dilatation in 24.1% (14 of 58). In all of these cases extensive flow reversal zones could be demonstrated, the possible importance of which is discussed. Examinations in 9 patients with reimplantation of subclavian artery to the common carotid artery and grafting technique between these arteries and in 11 patients with reimplantation of vertebral artery to the common carotid artery demonstrated one occlusion of the ipsilateral vertebral artery.

Carotid Artery Thrombosis↗
PubMed1991

Pituitary adenomas with parasellar invasion.

Pituitary adenomas with extension into the parasellar space, the so called "cavernous sinus" can be demonstrated best using MRI. To improve the delineation from the venous compartments the use of unenhanced and enhanced MRI scans is essential. In 25 pituitary adenomas with surgically proven infiltration into the space of the cavernous sinus we correlated the MRI findings with our surgical observations. When the adenoma encases the intracavernous internal carotid artery or reaches as far as to the lateral aspect of the artery, invasion was present in all cases. The critical area where invasion could not be predicted from MRI is the distance between the medial and the lateral aspect of the intracavernous internal carotid artery. By measurement with the monoclonal antibody KI-67 it could be shown, that pituitary adenomas infiltrating the parasellar space have a statistically significant higher growth rate (p less than 0.001), compared to non-invasive adenomas. This is of special interest, because surgical cure becomes unlikely, when invasion into the space of the cavernous sinus is present.

Adenoma↗
PubMed1991

Modifications of temporal approaches: anatomical aspects of a microneurosurgical approach.

All subtemporal approaches have in common the risk of temporal lobe damage. To reduce the retraction of the temporal lobe we combine two synergistic modifications of temporal approaches to reach the prepontine space. The first is the temporary resection of the zygomatic arch which allows to bring the temporalis muscle more caudally and subsequently allows an anterior subtemporal approach with only minimal temporal lobe retraction. The second modification is the resection of the apex of the petrous bone after incision of the tentorium. This provides an excellent view into the posterior fossa between the trigeminal nerve medially, the internal carotid artery caudally and the internal auditory canal laterally. The anatomical aspects of a microneurosurgical approach regarding these modifications are reported and discussed.

Brain Neoplasms↗
PubMed1991

Course of the arteria vertebralis in its segment V1 from the origin to its entry into the foramen processus transversi.

The segment V1 of the arteria vertebralis (pathway from its origin from the a. subclavia to the entry into the respective foramen processus transversi) has a special significance in vascular surgery. Contrary to indications in the literature, we found 47.15% of the specimens to have a contorted course in this segment. The tortuosities carried by the respective vessels were found to be horizontal in 42.5%, in a sagittal direction in 30% and in the frontal plane in 27% of the cases. However, no significant difference was found between vessels carrying a tortuosity and those without, regarding the average lengths of the arteries concerned in the segment V1.

Aged↗
PubMed1988

Cavernous sinus surgery. Approach through the lateral wall.

The cavernous sinus is divided from the surgical point of view into three parts. The middle part consists of the lateral sinus wall, the cranial nerves III, IV, V, VI and the posterior siphonknee of the internal carotid artery. Lesions of this region, vascular as well as tumorous, can be exposed by approaching the lateral sinus wall. The surgical dissection through the sinus wall is based on some important anatomical details, which are described here. As a consequence a modified transcavernous approach will be introduced and demonstrated by 35 clinical cases.

Aged↗
PubMed1988

Salivary levels of gramicidin after use of a tyrothricin-containing gargle/mouth-wash and tyrothricin lozenges.

Three pharmaceutical preparations for the disinfection of the oropharynx were tested with regard to the gramicidin concentration obtained in the saliva after their appropriate application. Peak values followed a dose-concentration relationship and were highest after sucking a lozenge containing 10 mg tyrothricin (mean 109.3 mg/L) followed by that of a gargle/mouth-wash containing 667 mg tyrothricin/L (mean 21.1 mg/L) and of a lozenge containing 4 mg tyrothricin (mean 14.4 mg/L).

Adult↗
PubMedDate not supplied

Decontamination of the oral cavity. Effect of six local anti-microbial preparations in comparison to water and parafilm as controls.

Six preparations (four liquid and two solid) were tested in a double-blind crossover design for their anti-bacterial effect on aerobic and anaerobic bacteria in saliva of 12 volunteers. The four liquid preparations contained either tyrothricin, hexetidine, hydrogen peroxide or ethanol and were tested against a rinse with water as control. The two solid preparations, in the form of lozenges, contained tyrothricin in doses of 4 or 10 mg and were tested against parafilm. A single rinse with either tyrothricin or hexetidine resulted in a significant reduction of aerobic and anaerobic bacteria in saliva which lasted for the whole 1 h observation period and was considerably more effective than hydrogen peroxide or ethanol. Similar results were seen with the solid preparations. The lozenge containing 10 mg tyrothricin was the most effective and was the only formulation capable of reducing oral aerobic bacterial counts by a factor of approximately 100.

Adult↗