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F Bootz

Publications and source records attributed to F Bootz.

At least 37 records · Page 2Linked to original sources
PubMed2001

Transnasal and transsphenoidal MRI-guided biopsies of petroclival tumors.

Magnetic resonance imaging (MRI) allows excellent tissue characterization in the area of the petroclival region and can depict lesions not visualized with ultrasound or computed tomography (CT). The aim of this study was to demonstrate the clinical feasibility and utility of an interactive MR-guidance system to target and biopsy tumors in the petroclival region. MRI-guided biopsies of 10 patients with tumors in the clivus and petrous apex were performed in an open 0.5-T MR system. Lesions were targeted through a transsphenoidal or transnasal approach. Imaging during biopsies was achieved by a combination of standard and interactive mode. T1-weighted spin-echo, T2-weighted fast spin-echo (FSE), and three-dimensional T1-weighted gradient-echo (GRE) scans (standard mode) were selected to provide optimal tissue characterization for both the lesion and surrounding structures and varied according to the anatomic site. For interactive imaging, T1-weighted GRE and T2-weighted FSE sequences were used. We performed MRI-guided transsphenoidal biopsies in 10 patients who had lesions identified by CT (n = 5) and/or MRI (n = 10). The indications for biopsies were to differentiate between suspected malignant processes (n = 4 ) and benign processes (n = 6). Lesions adjacent to structures like the internal carotid artery were accurately targeted in particular. All biopsies were performed successfully and were the basis for selection of further treatment. No complications occurred during the procedures. An open MR system allows interactive control of biopsies in the area of the petroclival region, providing maximum patient safety and diagnostic accuracy not possible in other systems. The advantages of MRI tissue characterization are combined with an interactive, one-step method of localization and targeting, as well as tissue sampling. J. Magn. Reson. Imaging 2001;13:3-11.

Biopsy, Needle↗
PubMed2001

The use of open MRI in otorhinolaryngology: initial experience.

Intraoperative imaging in head and neck surgery is a useful tool in many situations. In addition to being helpful for intraoperative orientation, real-time imaging enables visualization of the progress of surgery and the completeness of tumor resection. Regions in the head and neck to which access is difficult, and which therefore have a high incidence of morbidity and risk for the patient, can be approached more easily and safely in an open MRI than in a conventional way. Interventions in the open MRI (Signa SP, 0.5 Tesla) were performed with nonmagnetic instruments and an MR-safe microscope. For intraoperative navigation, the integrated FlashPoint system is helpful, because it allows targeting of the tumor by a calculated virtual line. T1W spin-echo, T2W fast spin-echo, and 3D T1W gradient-echo sequences were used for high-resolution imaging. Real-time imaging is achieved by fast multiplanar spoiled gradient-echo sequences or T2 single-shot fast spin-echo sequences. From 1996 to the present, we biopsied 17 petroclival tumors, performed paranasal sinus surgery in five cases, biopsied two neck masses, and inserted tubes for brachytherapy in 12 cases. No complications were observed. In all surgical procedures, a good resolution was obtained with MRI, especially for soft-tissue structures. The tumor could be targeted exactly, and all specimens revealed the relevant histology. In paranasal sinus surgery, however, the success rate was lower because it was difficult to distinguish blood from pathologic tissue. The insertion of tubes for brachytherapy was successful in all cases. It was possible to apply the tubes parallel to each other, 1 cm apart. Relevant biopsies could be taken of both neck masses. The indications for the use of open MRI in otorhinolaryngology are biopsies of tumors in regions that are difficult to approach, such as the petrous apex and petroclival region, the parapharyngeal space, and the orbit. Furthermore, the open MRI can be useful in paranasal sinus surgery, in the evaluation of tissue resection, and in the detection of the anatomy of delicate structures such as the internal carotid artery, the skull base, and the orbit. In addition, active navigation in the open MRI is possible with the integrated FlashPoint system. The advantage over conventional navigation systems lies in the possibility of real-time imaging, which allows detection of tissue changes occurring during the procedure.

Biopsy↗
PubMed2001

Bone marrow transfer from wild-type mice reverts the beneficial effect of genetically mediated immune deficiency in myelin mutants.

Inherited demyelinating neuropathies are chronically disabling human disorders caused by various genetic defects, including deletions, single site mutations, and duplications in the respective myelin genes. We have shown in a mouse model of one distinct hereditary demyelinating neuropathy (heterozygous P0-deficiency, P0+-) that an additional null mutation in the recombination activating gene-1 (RAG-1--) leads to a substantially milder disorder, indicating a disease modifying role of T-lymphocytes. In the present study, we addressed the role of lymphocytes in the mouse model by reconstituting bone marrow of P0+-/RAG-1-- mice with bone marrow from immunocompetent wild-type mice. We compared the pathology and nerve conduction in double mutant mice (P0+-/RAG-1-- on a C57BL/6 background) with that in double mutants after receiving a bone marrow transplant. We found that the milder demyelination seen in the lymphocyte-deficient P0+-/RAG-1-- mutants was reverted to the more severe pathology by reestablishing a competent immune system by bone marrow transfer. These data corroborate the concept that the immune system contributes substantially to the pathologic process in this mouse model and may open new avenues to ameliorate human hereditary neuropathies by exploiting immunosuppressive treatments.

Animals↗
PubMed2001

Swallowing function after endoscopic resection of supraglottic carcinoma with the carbon dioxide laser.

From April 1998 to May 2000, 14 patients with supraglottic cancer underwent transoral laser surgery (T-stage T1-2: 11 patients, T3: 3 patients). In three patients, an epiglottectomy or hemi-epiglottectomy was performed. In 11 patients, further structures (false cords, the valleculae and the base of the tongue and/or parts of the arytenoid cartilage) had to be resected. Thirteen patients had to undergo neck dissection and post-operative irradiation. Tracheostomy was carried out prophylactically in two cases. Every patient received a nasogastric tube perioperatively. One week after surgery, an evaluation of dysphagia was performed by video endoscopy (VEED). Aspiration was the main problem; in no case did dysphagia occur. The aspiration was graded according to videolaryngoscopical classification. Four patients had an occasional and ten patients a permanent aspiration after surgery. According to this assessment, an individual deglutition therapy management was established. Ten patients with permanent aspiration received a temporary percutaneous endoscopic gastrostomy (PEG) and were integrated in a rehabilitation programme (stimulation of the swallowing reflex, training of compensatory swallowing manoeuvres, dietary regime). Due to this training programme, the PEG could be removed in eight patients after 2-9 months. No patient needed a laryngectomy or a tracheostomy due to aspiration. There were no cases of aspiration-associated pneumonia. To obtain satisfying functional results after transoral laser surgery of supraglottic cancers with resection of the epiglottis, post-operative deglutition management, consisting of video endoscopy, a training programme and often a PEG, is necessary.

Adult↗
PubMed2001

CT and MR imaging after middle ear surgery.

This article describes the current value of imaging in patients after stapes surgery and surgery after chronic otitis media including cholesteatoma. Possibilities and limits of computed tomography (CT) and MRI are described and most important investigation parameters are mentioned. After otosclerosis surgery, CT is the method of first choice in detection of reasons for vertigo and/or recurrent hearing loss in the later postoperative phase. CT may show the position and condition of prosthesis, scarring around the prosthesis and otospongiotic foci. Sometimes, it gives indirect hints for perilymphatic fistulas and incus necrosis. MRI is able to document inner ear complications. CT has a high negative predictive value in cases with a free cavity after mastoidectomy. Localized opacities or total occlusion are difficult to distinguish by CT alone. MRI provides important additional information in the differentiation of cholesterol granuloma, cholesteatoma, effusion, granulation and scar tissue.

Cholesteatoma↗
PubMed2001

Case report. Mycotic arteritis due to Aspergillus fumigatus in a diabetic with retrobulbar aspergillosis and mycotic meningitis.

A 74-year-old man with diabetes mellitus type II, retinopathy and polyneuropathy suffered from exophthalmus, ptosis and diplopia. Magnetic resonance imaging and computer tomography showed a space-occupying process in the right orbital apex. An extranasal ethmoidectomy accompanied by an orbitotomia revealed the presence of septated hyphae. Aspergillus fumigatus was grown from the tissue. After surgical removal of the fungal masses, therapy with amphotericin B (1 mg kg(-1) body weight) plus itraconazole (Sempera, 200 mg per day) over 6 weeks was initiated. Five months later the patient's condition deteriorated again, with vomiting, nausea and pain behind the right eye plus increasing exophthalmus. Antifungal therapy was started again with amphotericin B and 5-fluorocytosine. Neutropenia did not occur. The patient became somnolent and deteriorated, a meningitis was suggested. Aspergillus antigen (titre 1:2, Pastorex) was detected in liquor. Anti-Aspergillus antibodies were not detectable. Both the right eye and retrobulbar fungal masses were eradicated by means of an exenteratio bulbi et orbitae. However, renal insufficiency and an apallic syndrome developed and the patient died. At autopsy, a mycotic aneurysm of the arteria carotis interna dextra was detected. The mycotic vasculitis of this aneurysm had caused a rupture of the blood vessel followed by a massive subarachnoidal haemorrhage. In addition, severe mycotic sphenoidal sinusitis and aspergillosis of the right orbit were seen, which had led to a bifrontal meningitis.

Aged↗
PubMed2001

[Value of magnetic resonance tomography for interventions in the ENT specialty].

PURPOSE: Presentation of new concepts and applications of MR-guided head and neck surgery are presented. Examples of diagnostic and therapeutic procedures such as evaluation of transseptal tumor biopsies, placement of afterloading catheters for brachytherapy, and microscopic surgery of paranasal sinuses in the open MRI are discussed. MATERIAL AND METHODS: 24 MRI-guided ENT-procedures (14 transsphenoidal biopsies, one transnasal biopsy, 6 placements of brachytherapy catheters, and 3 operations of the paranasal sinuses) were performed in an open 0.5 T MR system. RESULTS: Localisation and/or extension of all lesions as well as the placement of biopsy needles or catheters were determined with great precision during the interventions. CONCLUSIONS: Surgical risk and postoperative morbidity are significantly reduced in MR-guided surgery of the petroclival region and the region of head and neck compared to other, conventional methods. Thus, interventional MRI-guidance optimizes minimal invasive surgery and catheter placement in difficult anatomical regions like the petroclival region.

Adolescent↗
PubMed2001

Magnetic resonance imaging--guided biopsies of the petrous apex and petroclival region.

OBJECTIVE: To analyze the advantages in safety and precision of biopsies of the petrous apex and petroclival region using open magnetic resonance imaging (MRI). SETTING: The University of Leipzig Medical Center. PATIENTS: Biopsies were taken in 13 patients with tumors of the petrous apex and petroclival region. INTERVENTION: With the patient in the 0.5-T intraoperative MRI system (Signa SP; General Electric Medical Systems, Boston, MA, U.S.A.), biopsies were taken from the petrous apex and the petroclival region under imaging control by transseptal, transsphenoidal access. The region of interest was approached with a virtual pointer (Flashpoint Position Encoder; Image Guided Technologies, U.S.A.) and marked with a gadolinium-filled pointer. RESULTS: In all patients, the authors obtained enough tissue for histologic study, which also proved to be the suspected tumor. One patient had a bone cyst, another had a malignant lymphoma, and another two a cholesterol granuloma originating from the petrous apex. Three other patients had metastases (carcinoma of the breast, bronchial carcinoma, and unknown origin). Three patients had a meningioma, and another three a chordoma. The authors did not see any postoperative complications. CONCLUSIONS: In the authors' experience, the transsphenoidal access is favorable for approaching and sampling lesions of the petrous apex and the petroclival region. This route, however, is disadvantageous because the course of the internal carotid artery and the brainstem narrow the surgical space to the petrous apex. Open MRI in these cases is very useful because it allows a safe approach to the tumor by navigation and by visualizing the anatomic structures in real-time imaging.

Adult↗
PubMed2001

CUP (carcinoma of unknown primary) syndrome in head and neck: clinic, diagnostic, and therapy.

BACKGROUND: Up to 10% of all cervical lymph node metastases present without a known primary site. Between 70 and 80% of the found primary tumors are located in the head and neck region, because cervical lymph nodes represent the lymph drainage of the head and neck. PATIENTS AND METHODS: We demonstrate the clinic, diagnostic management and therapy of carcinoma of unknown primary (CUP) in this retrospective study of 75 patients who primarily presented cervical metastases with unknown primary tumor at the Otorhinolaryngological Department of the University of Leipzig, Germany. RESULTS: A primary tumor was found in 44% of the patients, and 76% of the primary tumors were localized in the head and neck region. The overall 5-year survival rate was 13.3%. The 34 patients with pretherapeutically detected primary tumors showed a tendency towards better survival, with a 5-year survival rate of 21% compared to 10% in patients with undetected primary. CONCLUSIONS: Following a thorough physical examination, radiologic imaging, i.e., computed tomography and/or magnetic resonance imaging, of the head and neck region as well a chest X ray, panendoscopy with biopsy of the most probable tumor sites, and diagnostic tonsillectomy should be performed. Further diagnostic procedures as gastroenterologic, urogenital and gynecological examinations should be performed, depending on histology and location of the node and under consideration of cost-benefit analysis. Curative treatment should at least include ipsilateral neck dissection and adjuvant irradiation of the complete cervical lymph drainage. In the literature, radiation of the laryngopharyngeal mucosa is still discussed controversially: some authors recommend the irradation of the pharyngeal mucosa extending from the nasopharynx to the upper esophagus, whereas others regard the resulting side effects as too high compared to the expected benefit.

Biopsy↗
PubMed2000

Immunophenotyping of peripheral blood leukocytes by laser scanning cytometry.

Many clinical situations demand repeated analyses of blood parameters but permit only minimal amounts of peripheral blood to be taken, e.g., in neonates with low birth weight, during extensive operations of young children, or in patients with restricted bone marrow function. In these cases laser scanning cytometry is the ideal tool to determine the distribution of different leukocyte-subsets. The purpose of this protocol is to describe stepwise a new method of immunophenotyping by laser scanning cytometry. In this assay nuclear DNA is stained by 7-aminoactinomycin-D (7-AAD) and surface antigens are detected by direct three-colour immunofluorescence. For data acquisition, measurements are triggered on the 7-AAD-fluorescence. Data are obtained for forward scatter, green, orange, and long red fluorescence by excitation with the argon-laser, and for far red fluorescence by excitation with the helium-neon-laser. Using this protocol the amount of peripheral blood needed is minimised to 10 microl. Specimens can be stained a second time in a different way and analysed repeatedly and archived.

Antigens, CD↗
PubMed2000

Immune deficiency in mouse models for inherited peripheral neuropathies leads to improved myelin maintenance.

The adhesive cell surface molecule P(0) is the most abundant glycoprotein in peripheral nerve myelin and fulfills pivotal functions during myelin formation and maintenance. Mutations in the corresponding gene cause hereditary demyelinating neuropathies. In mice heterozygously deficient in P(0) (P(0)(+/-) mice), an established animal model for a subtype of hereditary neuropathies, T-lymphocytes are present in the demyelinating nerves. To monitor the possible involvement of the immune system in myelin pathology, we cross-bred P(0)(+/-) mice with null mutants for the recombination activating gene 1 (RAG-1) or with mice deficient in the T-cell receptor alpha-subunit. We found that in P(0)(+/-) mice myelin degeneration and impairment of nerve conduction properties is less severe when the immune system is deficient. Moreover, isolated T-lymphocytes from P(0)(+/-) mice show enhanced reactivity to myelin components of the peripheral nerve, such as P(0), P(2), and myelin basic protein. We hypothesize that autoreactive immune cells can significantly foster the demyelinating phenotype of mice with a primarily genetically based peripheral neuropathy.

Animals↗
PubMed2000

[Axonotmesis].

Explore the source record for details and available documents.

Bell Palsy↗
PubMed2000

[Neuromuscular reinnervation of mimetic muscles. A histomorphologic study of the zygomatic muscle of the rabbit].

To evaluate occurrences of reinnervation and degeneration, the portio auricularis of the zygomatic muscle was reinnervated (either primary or secondary reinnervation) with an interval of 6 weeks, using a neuromuscular transplant of the sternohyoid muscle, which was left at the ansa hypoglossi. Histological examination was performed 6 and 12 weeks later. Enzymatic stains for myofibrillar ATPase were used for differentiation of muscle fibre types. Histomorphological features of denervation and reinnervation were analysed. Six weeks after denervation and primary neuromuscular transplantation, type grouping in regions close to the transplanted muscle were detectable as signs of reinnervation. After a period of 12 weeks, the progressing reinnervation was proved by type grouping in distal areas of the muscle far from the area of transplantation. At the same time, differentiation of fibre typing in the type grouping areas increased. All denervated and reinnervated muscles had pathological variations of fibre diameter. Primary reinnervated muscles showed tendency of normalization in variation of diameter. Compared with primary reinnervated muscles, secondary reinnervated muscles with an interval of 6 weeks showed pronounced polymorphology of fibres and a high pathological increase of the variation of fibre diameters. The interfascicular space was significantly spread. The tendency of reinnervation with incidence of fibre type grouping was comparable to primary reinnervated muscles and also occurred 6 weeks after transplantation.

Animals↗
PubMed2000

[Quality assurance in ENT tumor surgery].

BACKGROUND AND OBJECTIVE: Quality control is of special importance in head and neck oncology since the quality of medical care constitutes a vital parameter for the diseased patient. In contrast to other medical specialties, no quality assurance program for head and neck cancer patients has yet been established in Germany. Therefore, a survey was conducted to assess the quality assurance instruments that are in use today in otorhinolaryngology-head and neck (ORL-HNS) centers. PATIENTS AND METHODS: In a nationwide survey, questionnaires were sent out to 146 German ORL-HNS departments (the return rate was 75%). RESULTS: 56% of all departments apply dedicated quality assurance processes, and 38% have appointed a formal quality assurance officer. Interdisciplinary oncological conferences are held in the vast majority of all departments with the participation of radiation oncologists in 86 (78%), medical oncologists in 84 (76%), diagnostic radiologists in 82 (74%), and pathologists in 73 (66%). Morbidity-mortality conferences are held in seven departments (6%). A standardized follow-up of oncological patients is carried out in 95 units (86%), and 53 departments use computer-assisted data bases to organize their follow-up data (48%). A wide variety of documentation systems is in use throughout the country: 78 units (71%) offer formal follow-up to their oncological patients. CONCLUSIONS: This survey documents a wide-spread interest in quality assurance procedures. Many individual efforts are being undertaken. However, no uniform quality assurance or auditing system is currently in use in Germany nor is a commonly accepted data base available. The ability to offer oncological follow-up within the national social security system is generally considered indispensable for the maintenance of high-quality oncological care in ORL-HNS departments.

Germany↗