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R Fischbach

Publications and source records attributed to R Fischbach.

At least 19 recordsLinked to original sources
PubMed2000

Limitations of magnetic resonance imaging in the evaluation of perineural tumor spread causing facial nerve paralysis.

OBJECTIVE: To present and discuss the clinical presentation and treatment in patients with long-duration unilateral facial paralysis and normal magnetic resonance imaging (MRI) findings. DESIGN: Case series. SETTING: Ear, nose, and throat department of the University of Cologne, Cologne, Germany. PATIENTS: A total of 486 patients with unilateral facial paralysis who were treated from 1986 to 1998. Besides the usual diagnostic workup, a complete electrophysiological evaluation, including investigations such as needle electromyography and neuromyography (also known as electroneurography), of the facial nerve was performed at repeated intervals. In 19 patients, a malignant tumor was delineated with ultrasonography or MRI. In 8 of these patients, the initially performed MRI did not detect any parotid gland lesion causing the paralysis, whereas long duration of the paralysis and electroneurography indicated malignancy. RESULTS: Exploration surgery was performed as total parotidectomy in these 8 patients and malignant parotid gland tumors were proved in all 8 patients. CONCLUSIONS: Individuals with facial nerve paralysis without any signs of regeneration 6 months after the onset of paralysis and/or persistent electrophysiological evidence of ongoing neuronal degeneration should undergo surgical exploration of the parotid gland and facial nerve, even if MRI studies show no tumoral lesion.

Adenocarcinoma↗
PubMed2000

[Chronic recurrent parotitis in childhood in monozygotic twins. Magnetic resonance sialography].

Recurrent parotitis is rare in childhood. Its occurrence is characterized by recurrent episodes of swelling and pain in the parotid gland, which are usually accompanied by fever and malaise. Inflammation usually resolves spontaneously during adolescence. The disorder is a condition of unknown etiology. Sialectasis and stricturing occurs in the distal ducts, whereas inflammation of the gland and duct epithelium is probably caused by a low salivary flow rate. Which one can be considered the primary event or secondary change remains unknown. The main-stay of diagnosis is sialography, which depicts typical intraparotidal duct system lesions as strictures or ectasias and excludes sialolithiasis. We here report two 10-year-old male monovular twins who suffered from recurrent swelling and pain in only their left parotid glands. Symptoms were noted approximately every 6 weeks in both patients strictly. Characteristic sialectasis of the distal ducts was demonstrated by magnetic resonance-sialography. Our findings support the hypothesis that recurrent parotitis is caused by a congenital abnormality of the salivary gland ducts. Diagnostic imaging was performed by magnetic resonance imaging during the acute phase of the disease. This technique helps to make the diagnosis without retrograde application of a contrast agent.

Child↗
PubMed2000

[Detection and quantification of coronary calcification: an update].

The demonstration of calcification of the coronary arterial wall indicates the presence of coronary heart disease (CHD). The prevalence of coronary calcifications increases with age. The extent of the calcifications correlates with the total coronary plaque burden and with the probability of a future myocardial infarction in symptomatic patients. In asymptomatic subjects with risk factors for a myocardial event demonstration of coronary calcifications is diagnostic for coronary atherosclerotic disease before clinical manifestation of the disease. Exact quantification of coronary arterial calcifications (calcium scoring) has become possible with electron beam computed tomography (EBCT) or ECG triggered subsecond CT scanners. Further improvements in the detection of coronary calcifications can be expected with the introduction of multi-slice CT. The prognostic relevance of coronary calcium scoring in asymptomatic high-risk patients is not yet clearly defined. It remains to be clarified whether newer, volume based methods of calcium quantification will be superior to the classic calcium score (Agatston-Score) for risk assessment and follow-up in this patient group.

Calcinosis↗
PubMed2000

Results of electrochemical therapy of colorectal liver metastases in rats followed up by MRI.

RATIONALE AND OBJECTIVES: Direct-current or electrochemical therapy is an alternative method for local tumor therapy. Until recently, it was mainly applied in China and was relatively unknown in the Western world. This study examines the feasibility and effectiveness of applying direct-current therapy in liver metastases of colorectal carcinomas in an animal model. METHODS: Liver metastases were implanted in 47 BDIX rats by subcapsular injection of cells from a colorectal strain (DHD/K12). The success rate of implantation and the size of the tumors were determined after 3 weeks by MR imaging (T2-weighted turbo spin-echo images; relaxation time 1,800 ms, echo time 80 ms). The direct-current therapy was applied by one platinum electrode placed in the center of the tumor and four at the periphery of the tumor. Suitable therapy parameters were established in a pilot study by comparing four different methods of direct-current therapy with a control group. The methods varied with respect to the electrode polarity and the applied voltage. In a second series of investigations, tumor growth was monitored by MR imaging 3 and 5 weeks after therapy. RESULTS: The tumor implantation rate was 92.6% at a tumor cell concentration of 8 x 10(5)/mL. The most effective therapy method was achieved by placing an anode at the center of the tumor and four cathodes at the periphery, with an applied charge of 80 C/cm3. Complete tumor necrosis was observed in 54% of cases. In the follow-up measurements, the mean tumor diameter was 0.65 cm at 3 weeks after therapy and 0.76 cm at 5 weeks after therapy. In comparison with the control group (1.08 and 1.53 cm, respectively), this represented a significant reduction in tumor growth rate. CONCLUSIONS: This study is the first to demonstrate an antitumoral effect of direct-current therapy on liver metastases of colorectal cancer in rats.

Animals↗
PubMed2000

Rare benign tumors: laryngeal and hypopharyngeal lipomata.

Lipomata of the larynx and the hypopharynx are very rare benign lesions; as they look macroscopically like retention cysts, their diagnosis is usually made after surgery. Sometimes, lipomata of the hypopharynx become very large and life-threatening. Plain fluoroscopy and fluoroscopy aided with barium often fail to depict the lesion if it is localized subepiglottically; standard barium swallow examination and computed tomography allow an accurate diagnosis to be made in many cases, although magnetic resonance imaging is still more accurate and allows not only a more specific diagnosis of the lesion, but also a better depiction of the origin of the frequently pedunculated tumor and its extension into the parapharyngeal space. This paper adds 6 cases of hypopharyngeal and 1 case of laryngeal lipoma to the literature and discusses modern diagnostic and therapeutic strategies.

Aged↗
PubMed1999

Condylar restoration after early TMJ fractures and functional appliance therapy. Part II: Muscle evaluation.

The aim of this study was to analyze and to describe the condition of the lateral pterygoid muscle during and after functional appliance therapy in children who had sustained condylar fractures. The treatment group consisted of 19 patients with an average age of 13.4 years, who had sustained a unilateral fracture at an average age of 8.4 years and had been treated functionally for 6 to 8 months. Muscle condition was assessed through axial soft tissue description. The volume and density of the lateral pterygoid muscle were measured in both groups and were compared on the basis of sex, age and fracture type. 74% of the patients in the follow-up group showed muscle differences of more than 10% between the 2 sides. In 2/3 of these patients the lateral pterygoid of the fracture side was 13 to 69% smaller. The volumes of the contralateral pterygoid muscles in the 2 patient groups differed by 10% on the basis of sex. Both in the treatment group and in the follow-up group the volume difference between the healthy and fractured side was as high as 70% depending on localization and type of fracture. Deep fractures and fractures with complete dislocation of the condyle evoked the most serious reduction in muscle volume.

Adolescent↗
PubMed1999

Magnetic resonance sialography.

To evaluate a new noninvasive sialographic technique, we applied a new magnetic resonance technique to 10 healthy volunteers and 21 patients with lesions of the parotid gland. In addition to the usually performed T(1) and T(2) cross-sectional sequences, a heavily T(2)-weighted sequence (TR = 3600 msec, TE = 800 msec) was performed that allowed depiction of the fluid-filled parotid duct system. Twenty-one patients with benign as well as malignant parotid gland pathologies were examined: sialadenitis (n = 6), sicca syndrome (n = 2), pleomorphic adenoma (n = 4), carcinoma of the parotid gland (n = 2), lymphoepithelial carcinoma (n = 1), cystadenolymphoma (n = 3), non-Hodgkin's lymphoma (n = 2), and congenital duct dilatation (n = 1). Stenseńs duct was reliably depicted in all volunteers and patients. The primary branching ducts were reliably depicted in all normal cases. Intraglandular and extraglandular duct dilatations and duct strictures were well depicted in patients with chronic sialadenitis. Sialolithiasis with a calculus obstructing the duct was demonstrated in 2 cases. In conclusion, Initial experience indicates that magnetic resonance sialography can be applied successfully to investigate the duct system of the parotid gland. The usually performed cross-sectional MRI (T(1)- and T(2)-weighted images, gadolinium-DTPA) depicts the internal architecture of the parotid gland with high reliability. Magnetic resonance sialography with heavily T(2)-weighted images adds important information about the ductal system. Because it is completely noninvasive, the only contraindications are the ones generally accepted for MRI.

Adult↗
PubMed1999

Spiral CT angiography of the abdominal aorta. Comparison of iodixanol and ioversol.

RATIONALE AND OBJECTIVES: Enhancement characteristics of a nonionic, dimeric, isotonic contrast medium (iodixanol [Visipaque]) were compared with a nonionic, monomeric contrast medium (ioversol [Optiray]) of the same iodine concentration in spiral computed tomography angiography (CTA) of the abdominal aorta. METHODS: Spiral CTA was performed in 78 patients referred for suspected renal artery stenosis (n = 35) and abdominal aortic aneurysm (n = 43). A test bolus was used to time the scan delay, and all patients were injected with 150 ml contrast medium (320 mgI/ml) of either iodixanol (n = 40) or ioversol (n = 38). Contrast enhancement was measured in the aorta, renal arteries, and renal parenchyma. RESULTS: All mean aortic enhancement was slightly higher with iodixanol than ioversol, measured at three different levels (celiac trunk 315 Hounsfield units [HU] versus 300 HU, renal arteries 325 HU versus 312 HU, aortic bifurcation 276 HU versus 266 HU). However, none of them were statistically significant (e.g., P = 0.26 at the celiac trunk level). Similar results were observed in renal artery and parenchyma enhancements. CONCLUSIONS: Iodixanol and ioversol had similar enhancement characteristics in the early arterial phase. Both substances were well tolerated and seem to be well suited for spiral CTA.

Adult↗
PubMed1999

Comparative use of magnetic resonance imaging and electrophysiologic investigation for the prognosis of head injury.

BACKGROUND: To compare magnetic resonance imaging (MRI) and electrophysiologic investigation as prognostic methods in acute head injury. METHODS: Fifty-seven patients suffering moderate to mild (Glasgow Coma Scale score > 8) or severe (Glasgow Coma Scale score < 8) head injury were included. Both groups were analyzed as a total and separately for outcome as assessed by Glasgow Outcome Score. Two outcome groups were separated (Glasgow Outcome Score 1-3: unfavorable vs. Glasgow Outcome Score 4-5: favorable). MRI scans (T1-, T2-, T2*-sequences; transverse, coronal, and sagittal slices) were obtained 1 to 39 days after trauma (mean, 14 days). Electrophysiologic investigations consisted of median nerve-evoked somatosensory responses to assess corticosubcortical function and brain stem auditory-evoked potentials and brain stem reflexes for brain stem function. Recordings were performed 24 to 72 hours after trauma and repeated every 3 to 5 days. RESULTS: Evaluation of all patients revealed a prognostic significance of MRI lesions within the corpus callosum, the basal ganglia, the hippocampus, the midbrain, and the pons. In the severe head injury subgroup, significance was limited to lesions within the corpus callosum, the basal ganglia, and the midbrain. Among the electrophysiologic findings, dysfunction of the corticosubcortical region as well as of the midbrain were linked to an unfavorable outcome. In severe head injury, prognostic significance was restricted to bilateral corticosubcortical dysfunction. A statistical test for diagnostic convergence of both methods indicated a distinct convergence only for lesions of the midbrain and the pons. CONCLUSION: MRI scans performed early after head injury provide several indicators for unfavorable outcome. Electrophysiologic investigations add to this prognostic evidence. Both methods have comparably high specificity. However, because of the higher density of prognostic information obtained, MRI seems superior to electrophysiologic testing.

Adolescent↗
PubMed1998

[Mycotic aneurysm in endocarditis lenta as the etiology of intraparenchymatous cerebral hemorrhage].

CASE REPORT: A 49-year-old male was admitted for left-side headache and mild speech defect. Clinical examination showed a pansystolic murmur of mitral regurgitation and mild Wernicke aphasia. In laboratory studies ESR and CRP were increased. Computed tomography of brain revealed a left temporoparietal hematoma. Echocardiographic examination demonstrated vegetations and mitral valve perforation. In blood cultures grew alpha-streptococci. Cerebral angiography was performed and a fusiform aneurysm on a distal branch of the left middle cerebral artery was identified. Follow-up angiography showed a total resolution of the aneurysm after 6 weeks of intravenous antibiotics. CONCLUSION: This case demonstrate that patients with intracerebral hematomas associated with infectious endocarditis should be investigated for mycotic intracranial aneurysm.

Aneurysm, Infected↗
PubMed1998

Condylar restoration after early TMJ fractures and functional appliance therapy. Part I: Remodelling.

The aim of this study was to measure quantitatively and to analyze the process of condylar restoration during and after functional appliance therapy with an activator in children and juveniles who had sustained condylar fractures. Spiral computed measurement of condylar morphology was performed in order to quantify the association described in the literature between condylar remodelling and age as well as certain types of fracture. Nineteen patients with an average age of 13.4 years, who had sustained a functionally treated unilateral condylar fracture 4.9 years earlier on average, were included in the present study as the follow-up group. Twenty patients, who had sustained a unilateral fracture at an average age of 8.1 years and had been treated functionally for 6 to 8 months, formed the treatment group. The condylar dimension and the condylar neck length of the ipsilateral and of the contralateral temporomandibular joints were measured from the axial and parasagittal reconstructions and were compared on the basis of sex, age and fracture type. The mediolateral condylar dimension of the follow-up group showed a sex-specific difference of 0.2 cm on the contralateral side and 0.4 cm on the ipsilateral side. The fracture side condyle indicated a relative mediolateral decrease of 4.2% and an anteroposterior increase of 12.6%. Shortening of the condylar neck and excessive bony overgrowth were found to occur more often in fractures with displacement and in low fracture types. The "10-plus" subgroup at time of trauma showed a significantly greater variation and greater differences in mediolateral and anteroposterior condylar dimension than the younger patients.

Adolescent↗
PubMed1998

The lateral calcaneal artery.

An anatomic study of the lateral extraosseous and intraosseous arterial supply of the calcaneus and the lateral soft tissue was carried out on 10 fresh lower adult cadaver legs using different anatomic and radiologic procedures (plastination, modified Spalteholz clearing technique, digital subtraction and rotational angiography and computed tomographic angiography). Consistent patterns of extraosseous and intraosseous lateral calcaneal vascular anatomy were demonstrated. The lateral calcaneal artery is a branch of the anterior tibial artery which crosses over the calcaneal tuberosity and forms a large lateral arch with the lateral tarsal artery which is a branch of the dorsalis pedis artery. The intraosseous circulation is supplied laterally by the lateral calcanear artery, medially via the short branches of the lateral plantar artery. Comparing magnet resonance images after fresh calcaneal fractures the lateral calcanear artery may be interrupted by the impacted lateral bulge, by the conventional lateral surgical approach, or by applying a lateral osteosynthesis plate. This may cause avascular bone necrosis. Furthermore the lateral calcanear artery can clinically serve as a vascular pedicle for a local rotational skin flap to cover soft tissue defects of the heel.

Adult↗
PubMed1998

[Magnetic resonance sialography. A new diagnostic method for imaging salivary duct patency].

The new technique of non-invasive magnetic resonance (MR) sialography was evaluated for normal and various pathologic conditions of the parotid gland. Ten volunteers and 15 patients with various symptomatic diseases of the parotid gland were tested in the present study. Diseases included pleomorphic adenoma, cystadenolymphoma, carcinoma ex pleomorphic adenoma, ductal carcinoma, adenoid cystic carcinoma, lymphoepithelial carcinoma, non-Hodgkin's lymphoma, sialolithiasis, sialadenitis, Heerfordt's syndrome and congenital duct ectasies. In addition to the usually performed T1 and T2 cross-sectional sequences a heavily weighted T2 sequence (TR 3600, TE 800) was performed and allowed depiction of a fluid-filled parotid duct. Results showed that the main parotid and primary branching ducts were depicted reliably in all normal cases and all patients, except one with sicca syndrome. Pathological conditions such as duct dilatations, duct strictures, obstructing duct calculus and irregular shapes and courses of the ductal system were demonstrable. While X-ray sialography obtained a higher resolution, only MR sialography was able to depict dilated ducts proximal from a complete obstruction, as well as all ductal cysts. Our findings show that MR sialography can be applied successfully to investigations of the parotid gland system. There have been no contraindications or complications to date because MR sialography is non-invasive. The technique will also allow the salivary ducts and lesions to be differentiated from the course of the facial nerve.

Constriction, Pathologic↗
PubMed1998

Influence of the hepatobiliary contrast agent mangafodipir trisodium (MN-DPDP) on the imaging properties of abdominal organs.

To assess the influence of Mangafodipir Trisodium on the imaging properties of abdominal organs when using T1-weighted gradient-echo (GE) and T2-weighted turbo spin-echo (TSE) sequences, thirty patients with focal lesions in the liver were examined at a field strength of 1.5 T before and after intravenous administration of Mangafodipir Trisodium (dose: 5 micromol/kg of body weight). Administration of Mangafodipir Trisodium led to a significant increase in the signal intensity of the liver tissue (p < 0.001), the spleen (p < 0.01), the pancreas (p < 0.001), and the kidneys (p < 0.001) in the T1-weighted GE sequence, while there was no relevant enhancement in fatty tissue and the musculature. In the T2-weighted turbo spin-echo sequence, there was no relevant change in the signal following administration of a contrast agent. The contrast-to-noise ratio (C/N) between the lesions and the liver tissue increased significantly in the post-contrast T1-weighted GE sequence (p < 0.001), while there was no change in the contrast-to-noise ratio in the post-contrast T2-weighted turbo spin-echo sequence. The contrast-to-noise ratio of the plain T2-weighted TSE sequence was significantly higher than that in the post-contrast T1-weighted GE sequence (p < 0.001). Although Mangafodipir Trisodium was primarily developed as a hepatobiliary contrast agent for demonstration and differentiation of liver lesions, it also affects the signal levels in the pancreas, spleen, and kidneys in the T1-weighted image. Awareness of this effect on the extrahepatic tissue makes it easier to interpret pathological findings in magnetic resonance imaging (MRI) of the abdomen.

Abdomen↗
PubMed1998

Effect of early orthopedic intervention on hemifacial microsomia patients: an approach to a cooperative evaluation of treatment results.

The purpose of the present study was to analyze the effects of early orthopedic intervention in patients with hemifacial microsomia, clinically as well as radiologically, by computed tomographic examination to assess soft and hard tissue temporomandibular joint changes. Five patients, one with mandibular dysostosis, one with otomandibular dysostosis, two with Goldenhar syndrome, and one with a surgically revised fibroma of the right mandible that was reconstructed by a costochondral graft, were treated by means of an activator functional appliance. During functional appliance treatment, all patients showed improvement of function and occlusion, and facial asymmetry was reduced. Spiral computed tomographic examination before and during treatment provided data on the bony and muscular deficiencies. The volume and density of the lateral pterygoid muscle was measured with the standard computed tomography software. Evaluation of soft and hard tissue conditions before treatment has shown that the most important factor "lack of soft tissues" can be compensated by excellent cooperation during functional therapy. Pretreatment volume of the affected lateral pterygoid muscle in all patients was significantly smaller than on the unaffected side. In three patients, volume measurements between 4 and 8 years demonstrated that the lateral pterygoid muscle on the affected side had a third, less than a third, and a fifth of the volume of the unaffected side. Although increase, stability, and decrease of the ratio of left and right condylar dimension, muscular volume, and density were found, long-term prognosis cannot be given in the cases with extreme muscular deficiencies after cessation of growth. Prepubertal orthopedic treatment success is a desirable and feasible presurgical or nonsurgical treatment goal for the interdisciplinary team approach. From a study of the pathologic, we learn much about the normal.

Child↗
PubMed1998

MRI examination of the TMJ and functional results after conservative and surgical treatment of mandibular condyle fractures.

Thirty patients with healed condylar fractures were included in this study. Ten patients were conservatively treated while in 20 patients the fractures were treated surgically. All patients were assessed using: magnetic resonance imaging of both temporomandibular joints (TMJs) to evaluate the disc position and morphology; radiographs to evaluate the alignment of the bony fragments after consolidation; and clinical examination including the stomatognathic functional status and mechanical axiography. The study shows that anatomical reduction of a low, displaced or dislocated condylar fracture by surgical approach may be of benefit for the functional recovery of the TMJ.

Adolescent↗