Biomedical subjects

M Streppel

Publications and source records attributed to M Streppel.

At least 19 recordsLinked to original sources

PubMed2007

[Multiple primary pleomorphic adenomas of the unilateral parotid gland].

BACKGROUND: Classical lateral parotidectomy is the standard surgical procedure for the management of lateral lobe parotid pleomorphic adenomas in most clinical centres. Extracapsular dissection and subtotal lateral parotidectomy are alternatively discussed in current literature and preferred by many authors. CASE: We report on a 20-year-old patient with multiple primary pleomorphic adenomas in the unilateral parotid gland, which preoperatively presented as a solitary tumour node. CONCLUSION: Considering this case we focus on the distinctive surgical procedures for the management of parotid pleomorphic adenomas. We work out, why lateral or even total parotidectomy are justified in the treatment of solitary palpable tumours and why we account lateral parotidectomy as the standard surgical procedure for the management of lateral lobe parotid pleomorphic adenomas.

Adenoma, Pleomorphic↗

PubMed2007

[Simulation and aggravation in ENT medical examinations. A prospective study].

OBJECTIVE: The occurrence and characteristics of simulation and aggravation in audiology still lack detailed scientific research. A reliable and reasonable classification of simulation and aggravation, which could help assess a patient's cooperative behavior, has not been defined. PATIENTS AND METHODOLOGY: All patients who underwent an audiological medical examination were included in this study prospectively. These patients were examined based on a well structured and predetermined sequence of actions. As a result, they were grouped into one of four categories, from category 0 for no simulation or aggravation to category III for severe simulation and aggravation. For category III, reliable and valid thresholds for pure tone audiometry only can be achieved by using objective audiological measurements such as brainstem electric response audiometry. Measured thresholds were then compared with simulated or aggravated thresholds and finally correlated with socio-economic factors. RESULTS: A total of 61 individuals were included in this study. Only 42% (26/61) showed no simulation or aggravation (category 0). In all 10% were grouped in category III. The remaining 48% fell into categories I and II. Statistical evaluation revealed no significant differences in thresholds between categories I, II and III. The tendency to simulation or aggravation increased with patient' age, level of education and the frequency of medical examinations prior to this investigation. CONCLUSION: Simulation and aggravation is a frequent phenomenon (approximately 58% of all audiological examinations). Additional work on defining a unique schema for the classification of simulation and aggravation is necessary. The use of such a schema is highly recommended.

Artifacts↗

PubMed2005

Axonal branching and recovery of coordinated muscle activity after transection of the facial nerve in adult rats.

Facial nerve surgery inevitablyleads to pareses, abnormally associated movements, and pathologically altered reflexes. The reason for this "post-paralytic syndrome" is the misdirected reinnervation of targets, which consists of two major components. First, due to malfunctioning axonal guidance, a muscle gets reinnervated by a "foreign" axon, that has been misrouted along a "wrong" fascicle. Second, the supernumerary collateral branches emerging from all transected axons simultaneously innervate antagonistic muscles and cause severe impairment of coordinated activity. Since it is hardly possible to influence the first major component and improve the guidance of several thousands of axons, we concentrated on the second major component and tried to reduce the collateral axonal branching. The efficiency of various treatments was evaluated in rats by determining: (1) the degree of post-operative axonal branching as estimated by the number of double-or triple-labeled perikarya after application of crystalline DiI, Fluoro-Gold (FG), and Fast Blue (FB) to the zygomatic, buccal, and marginal mandibular branch of the facial nerve respectively; (2) the accuracy of reinnervation as estimated by the number of double-labeled perikarya innervating the whisker pad muscles before and after surgery as shown by intramuscular injections of FG and FB respectively; (3) the recovery of vibrissal motor performance, estimated by a video based motion analysis. So far, we have tried to reduce branching by alteration of the afferent trigeminal input to the axotomized facial motoneurons and by focal application of: (1) neurite outgrowth fostering ECM proteins; (2) neutralizing antibodies to NGF, BDNF, CNTF, GDNF, IGF-I, and FGF-II; (3) suspensions of olfactory ensheathing cells, Schwann cells, and bone marrow stroma cells; and (4) pieces of autologous olfactory mucosa to the transection site. Although most of these manipulations do influence peripheral nerve regeneration to some extent, only the application of autologous olfactory mucosa yielded a major improvement, i.e., better function.

Animals↗

PubMed2003

Motoneuron adaptability to new motor tasks following two types of facial-facial anastomosis in cats.

The ability of the facial motor system to adapt to a new motor function was studied in alert cats after unilateral transection, 180 degrees rotation and suture of the zygomatic nerve, or transection and cross-anastomosis of the proximal stump of the buccal nerve to the distal stump of the zygomatic nerve. These procedures induced reinnervation of the orbicularis oculi (OO) muscle by different OO- or mouth-related facial motoneurons. Eyelid movements and the electromyographic activity of the OO muscle were recorded up to 1 year following the two types of anastomosis. Animals with a zygomatic nerve rotation recovered spontaneous and reflex responses, but with evident deficits in eyelid kinematics, i.e. the proper regional distribution of OO motor units was disorganized by zygomatic nerve rotation and resuture, producing a permanent defect in eyelid motor performance. Following buccal-zygomatic anastomosis, the electrical activity of the OO muscle was recovered after 6-7 weeks, but air puff-, flash- and tone-evoked reflex blinks never reached the control values on the operated side. Electromyographic OO activities and lid movements corresponding to licking and deglutition activities were observed on the operated side in buccal-zygomatic anastomosed animals up to 1 year following surgery. Mouth-related facial motoneurons did not readapt their discharges to the kinetic, timing and oscillatory properties of OO muscle fibres. A significant hyper-reflexia was observed following both types of nerve repair in response to air puffs, but not to light flashes or tones. In conclusion, adult mammal facial premotor circuits maintain their motor programmes when motoneurons are induced to reinnervate a foreign muscle, or even a new set of muscle fibres.

Adaptation, Physiological↗

PubMed2002

[Perioperative mortality in otorhinolaryngology tumor surgery].

BACKGROUND: Perioperative mortality is an important factor for quality assurance in surgery. For ENT-surgery only sparse data has been published. PATIENTS AND METHODS: A retrospective analysis of 1054 interventions performed on 775 consecutive patients treated surgically for benign and malignant tumors of the head and neck was conducted during a 3-year period in 1995-1998. RESULTS: Of these patients, 34.1% were female and 65.9% male. Age ranged from 4-88 years with a mean age of 54.8 years. 489 patients (63.1%) were treated for malignoma and 286 for benign tumors (36.9%). 0.9% (n = 7) of our patients (n = 775) died during the first 30 days after surgery. That means 0.66% of all surgical interventions (n = 1054) were followed by post-operative mortality. DISCUSSION: In otorhinolaryngological surgery, post-operative mortality seems to be acceptable and low compared to other medical disciplines. The challenge for surgery must be to reach and preserve low perioperative mortality rates in the future. Finding the individually correct indication for surgical treatment must be guaranteed in order to reach this aim.

Adolescent↗

PubMed2002

[Quality assurance indicators in an ENT practice].

BACKGROUND: According to German legislature, hospitals have to implement quality assurance (QA) programs, which are of particular importance in times of ongoing structural changes in healthcare. Amongst other internal methods of QA, indicators measuring the quality of total hospital performance can reflect medical outcome and the activities of physicians, nurses, and administrators. METHODS: Five indicators for measuring total hospital performance and for controlling total medical outcome were used in this study. RESULTS: Evaluation was time consuming, and some indicators showed a wide range, which could be explained by external reasons independent from internal quality. Valid values could be ascertained in the field of administrative quality, whereas in contrast the assessment of medical quality seemed to be more difficult. CONCLUSION: Due to current developments in German healthcare, the application of quality assurance methods such as the presented system of indicators is recommended.

Evaluation Studies as Topic↗

PubMed2002

Focal application of neutralizing antibodies to soluble neurotrophic factors reduces collateral axonal branching after peripheral nerve lesion.

A major reason for the insufficient recovery of function after motor nerve injury are the numerous axonal branches which often re-innervate muscles with completely different functions. We hypothesized that a neutralization of diffusable neurotrophic factors at the lesion site in rats could reduce the branching of transected axons. Following analysis of local protein expression by immunocytochemistry and by in situ hybridization, we transected the facial nerve trunk of adult rats and inserted both ends into a silicon tube containing (i) collagen gel with neutralizing concentrations of antibodies to NGF, BDNF, bFGF, IGF-I, CNTF and GDNF; (ii) five-fold higher concentrations of the antibodies and (iii) combination of antibodies. Two months later, retrograde labelling was used to estimate the portion of motoneurons the axons of which had branched and projected into three major branches of the facial trunk. After control entubulation in collagen gel containing non-immune mouse IgG 85% of all motoneurons projecting along the zygomatic branch sprouted and sent at least one twin axon to the buccal and/or marginal-mandibular branches of the facial nerve. Neutralizing concentrations of anti-NGF, anti-BDNF and anti-IGF-I significantly reduced sprouting. The most pronounced effect was achieved after application of anti-BDNF, which reduced the portion of branched neurons to 18%. All effects after a single application of antibodies were concentration-dependent and superior to those observed after combined treatment. This first report on improved quality of reinnervation by antibody-therapy implies that, in rats, the post-transectional collateral axonal branching can be reduced without obvious harmful effects on neuronal survival and axonal elongation.

Animals↗

PubMed2001

Exogenous antigen containing perivascular phagocytes induce a non-encephalitogenic extravasation of primed lymphocytes.

Recent evidence suggests that T-lymphocyte extravasation and CNS-parenchymal infiltration during autoimmune disease might be regulated by antigen-presenting (ED2(+)) cerebral/spinal perivascular phagocytes (CPP/SPP). Since the massive erythrocytic and leukocytic infiltrates in the CNS of rats with experimental allergic encephalomyelitis do not allow a precise differentiation between CPP/SPP and the invading cells in the Virchow-Robin space, we developed a new immune-response model whereby the extravasation of T-lymphocytes was not followed by other blood cells. Adult Lewis rats were sensitized to horseradish peroxidase (HRP). Subsequent intracerebroventricular (i.c.v.) injections of HRP and/or Fluoro-Emerald (FE) served to: (1) challenge the primed T-lymphocytes and (2) label the CPP/SPP for additional immunocytochemical analysis. We found that 24 h and 3 days after single, double, or triple antigen boosting T-lymphocytes (R73(+), W3/25(+), OX50(+)) entered the Virchow-Robin space but did not break through the astrocytic glia limitans. Instead they adhered to HRP-containing activated CPP/SPP (mabs OX-6(+), SILK6(+), CD40(+), CD80(+), CD86(+)). This selective contact was mediated neither by cell adhesion molecules (P-selectin, ICAM-1, VCAM-1), nor promoted by chemokine receptors (CCR1, CCR5) or chemokines (monocyte chemoattractant protein (MCP)-1, MIP-1alpha, MIP-1beta, RANTES). This non-inflammatory, but antigen-dependent lymphocyte extravasation provides optimal conditions to further study the CNS immune response.

Animals↗

PubMed2001

Hypoglossal and reticular interneurons involved in oro-facial coordination in the rat.

Chewing, swallowing, breathing, and vocalization in mammals require precise coordination of tongue movements with concomitant activities of the mimetic muscles. The neuroanatomic basis for this oro-facial coordination is not yet fully understood. After the stereotaxic microinjection of retrograde and anterograde neuronal tracers (biotin-dextran, Fluoro-Ruby, Fluoro-Emerald, and Fluoro-Gold) into the facial and hypoglossal nuclei of the rat, we report here a direct bilateral projection of hypoglossal internuclear interneurons onto facial motoneurons. We also confirm the existence of a small pool of neurons in the dorsal part of the brainstem reticular formation that project ipsilaterally to both facial and hypoglossal nuclei. For precise tracer injections, both motor nuclei were located and identified by the electrical antidromic activation of their constituent motoneurons. Injections of retrograde tracers into the facial nucleus consistently labeled neurons in the hypoglossal nucleus. These neurons prevalently lay in the ipsilateral side, were small in size, and, like classic intrinsic hypoglossal local-circuit interneurons, had several thin dendrites. Reverse experiments - injections of anterograde tracers into the hypoglossal nucleus - labeled fine varicose nerve fiber terminals in the facial nucleus. These fiber terminals were concentrated in the intermediate subdivision of the facial nucleus, with a strong ipsilateral prevalence. Double injections of different tracers into the facial and the hypoglossal nuclei revealed a small, but constant, number of double-labeled neurons located predominantly ipsilateral in the caudal brainstem reticular formation. Hypoglossal internuclear interneurons projecting to the facial nucleus, as well as those neurons of the parvocellular reticular formation that project to both facial and hypoglossal nuclei, could be involved in oro-facial coordination.

Animals↗

PubMed2001

Evaluation of muscle re-innervation employing pre- and post-axotomy injections of fluorescent retrograde tracers.

In experimental studies on peripheral nerve repair, the possibility to objectively compare original and post-operative innervation is of decisive importance for the selection of the proper nerve-reconstruction strategy. Herewith we report serious drawbacks encountered with the standard method of pre- and post-operative intramuscular injections of widely used retrograde neuronal tracers. Labeling of rat facial motoneurons by injection of Fast-Blue (FB; Group 1), Dil (Group 2), or Fluoro-Gold (FG; Group 3) into the whisker pad muscles was followed by transection and suture of the facial nerve. Two months later, the same rats received Dil (Group 1), FG (Group 2), and FB (Group 3) injections with the same parameters as the pre-operative injections. By quantitative evaluation of single- and double-retrogradely labeled perikarya of facial motoneurons, we tried to estimate the accuracy of re-innervation. Observations through a "UV-filter" (for FB-labeled perikarya) and a "rhodamine-filter" (for Dil-labeled perikarya) in Group 1 revealed an unexpected axotomy-triggered leakage of FB which compromised the counts. After pre-operative Dil labeling, nerve suture, and post-operative FG labeling (Group 2), Dil created an extracellular deposit in the whisker pad. Thus, the uptake of pre-operative tracer by sprouts of re-growing axons compromised counts of retrogradely labeled motoneurons. Employing the "UV-filter" in Group 3 (FG-, FB-, FG+FB-labeled perikarya), the emission of FB obscured that of FG and also compromised cell counts. The use of filter sets constructed ad hoc for detection of FG and FB rendered possible an objective comparison.

Amidines↗

PubMed2001

Cricopharyngeal muscle hypertrophy associated with florid myositis.

Hypertrophy of the cricopharyngeal muscle is a serious clinical condition that can cause severe dysphagic symptoms, including prolonged deglutition and postdeglutitive aspiration. Although the therapeutical concepts are well established, the pathogenic mechanism of cricopharyngeal hypertrophy remains unclear. We present a patient with a ten-year history of progressive dysphagia. The neurological and MRI findings were normal. However, videocineradiography showed severe hypertrophy of the cricopharyngeal muscle. This condition was first treated by injections of botulinum toxin, which did not alleviate the symptoms. Next, myotomy and muscle biopsy were performed. Histological evaluation disclosed lymphoplasmacellular florid myositis, single-fiber atrophy, and muscle fiber necrosis with phagocytosis. There were no signs of inclusion body myositis or oculopharyngeal muscular dystrophy. Our finding of severe cricopharyngeal muscle hypertrophy associated with myositis has been published previously (n = 34). The study presented here shows cricopharyngeal dysphagia associated with various systemic diseases, including motor neuron disease, general granulomatous disease, dermatomyositis, or inclusion body myositis. Isolated changes of the cricopharyngeal muscle were described in 65% of the cases.

Aged↗

PubMed2001

Progressive hearing loss in hearing impaired children: immediate results of antiphlogistic--rheologic infusion therapy.

OBJECTIVE: The question whether progressive sensorineural hearing loss during childhood is the fateful course of a main illness has been discussed controversially over 60 years. No medicamentous therapy with satisfactory results has been described in the literature. The goal of this study was to determine whether an infusion therapy, developed for the treatment of sudden hearing loss in the elderly, can induce recovery after progression in sensorineural hearing loss during childhood. METHODS: Out of 20 children suffering from acute progression in sensorineural hearing loss, seven children were treated with an infusion therapy containing prednisolone, pentoxifylline and a plasma expander (group I), and 13 children were not treated (group II). All children were advised not to use hearing aids for 6 weeks. RESULTS: In group I, we observed partial to complete restoration of hearing threshold towards the original hearing threshold given by previous routine controls in 6/7 children. In group II, only three children recovered, with the state of ten children's' hearing loss remaining unchanged. The long-term follow-up, however, showed no distinct difference in either group. CONCLUSION: Infusion therapy can be helpful when treating acutely progressing sensorineural hearing loss during childhood. The benefit for communicative competence has to be discussed. Further studies should be conducted.

Case-Control Studies↗

PubMed2001

[Infected epidermoid cyst as cause of peripheral facial palsy. A case report].

BACKGROUND: Extratemporal processes are rare causes of peripheral facial palsy. Only 17 cases of facial palsy in association with a suppurative or necrotic parotitis are reported in the literature. PATIENT AND RESULTS: We present a case of a peripheral facial palsy initiated by an infection of a epidermoid cyst, which consecutively involved the whole parotid gland. After abscess drainage and antibiotic therapy the inflammation process receded. The palsy persisted over a period of 4 weeks but improved completely. CONCLUSIONS: As the facial nerve was not enclosed by the abscess formation the palsy must have been caused indirectly. It may be assumed the inflammation spread into the Fallopian canal through the stylomastoid foramen and caused a metabolic imbalance similar to the supposed vicious circle for Bell's palsy. Due to the relapse tendency of inflammations of epidermoid cysts it is recommended to remove the entire cyst.

Adult↗

PubMed2000

Delayed rat facial nerve repair leads to accelerated and enhanced muscle reinnervation with reduced collateral axonal sprouting during a definite denervation period using a cross-anastomosis paradigm.

To establish the influence of prolonged denervation on the recovery of a motor nerve, the rat facial nerve was transected and denervated for 0 to 224 days. Then, the freshly transected hypoglossal nerve was sutured to the predegenerated facial nerve (hypoglossal-facial nerve anastomosis, HFA). Using this nerve cross-anastomosis paradigm we analyzed the nerve regeneration and muscle reinnervation 7 to 112 days post-suture operation (DPSO). After HRP injection into the whiskerpad 931+/-27 hypoglossal neurons were labeled at 112 DPSO after immediate HFA. Following 14 to 112 days denervation the number of labeled neurons increased to 138% (14 days delay), 154% (56 days), and 145% (112 days). In contrast, the reinnervation was poorer after 7 days denervation with the number of neurons increasing to 84%, and after long-term denervation of 224 days the number of neurons increased to 81%. The increase in amplitude of evoked electromyography wave after nerve suture correlated with the number of labeled neurons. After immediate HFA each regenerated motoneuron established on average 5.1 myelinated sprouts at 112 DPSO. The number of sprouts remained constant after delayed suture of 14 to 112 days, whereas the slower reinnervation after 7 or 224 days delay was accompanied by a massive sprouting of 9.1 or 8.1, respectively, sprouts per neuron. The muscles showed recovery after any denervation time. The muscle cross-sectional area continuously decreased with longer denervation time. This decrease was only significant after 224 days denervation (67% of the normal value). We conclude that motor nerve reconstruction achieves better functional results after a definite period of denervation when using a nerve cross-anastomosis paradigm.

Anastomosis, Surgical↗

PubMed2000

[The Stennert antiphlogistic-rheologic infusion schema in treatment of cochleovestibular disorders].

The pathogenetic mechanisms of acute cochleo-vestibular lesions are still unknown, but viral infections and vascular phenomena with impairment of microvascular perfusion are thought to play a major role. Between 1 July, 1986 and 28 February 1998, 1501 patients were treated with an infusion protocol using cortisone, dextrane 40 and pentoxifylline. Group 1 contained 1001 patients with sudden hearing loss, group 2a 107 patients with isolated tinnitus and group 2b 393 patients with labyrinthine disorders (among which were 81 patients with cochleovestibular dysfunction). The records were evaluated retrospectively. In group 1 complete hearing recovery occurred in 44.8%, partially in 40.4%, no change in 12.1% and worsened in 2.6%. In group 2a with isolated tinnitus 17.9% had a complete recovery, 43.9% partial recovery, 35.5% no change and 2.8% worsened symptoms. In group 2b vertigo disappeared in 56.8%, had partial recovery in 21.0% and did not change in 7.4%. In the 1501 patients treated, no significant side-effects were found to the medical interventions used. From these results we conclude that the infusion protocol is safe and effective in the treatment of cochleo-vestibular disorders.

Adolescent↗

PubMed2000

[Temporal inconsistency of neuromyography of the facial nerve in healthy probands].

Facial neuromyography is an objective electrophysiologic measurement used to assess prognosis for recovery from facial paralysis. In the present study variability over time of the amplitude ratio in healthy subjects was investigated. Twenty healthy subjects underwent four neuromyographic tests at intervals of one week. The study group consisted of 12 males and 8 females. Ages ranged from 23 to 36 years. The stimulation intensity required for supramaximal stimulation was 14.6 mA on average. The mean of the intra-individual side-to-side difference of the evoked compound action potential was 32.5%. Results of the four repeated tests ranged from no to 80% side-to-side differences in the same individual. The hypothesis of symmetrical evoked facial compound potentials was not supported by our data. As with previous investigators we found significant side-to-side differences in healthy subjects. Furthermore, we could also show for the first time that the amplitude ratio was not constant in every individual at repeated measurements. We conclude that there is a physiological variability that must be taken into account in the interpretation of facial nerve neuromyography.

Adult↗

PubMed2000

[Dependence of uni- and bilateral olfactory capacity on nasal airflow in patients with chronic rhinosinusitis].

OBJECTIVE: Olfactory dysfunction is a common finding in patients with chronic rhinosinusitis (CRS). The aim of this study was to investigate the relationship between olfaction and nasal flow as determined by active anterior rhinomanometry (AAR). METHODS: Thirty patients with CRS were included in this series. Patients' histories and subjective assessments of olfaction were documented with questionnaires. Smell tests, assessments of olfaction, AAR, and results of rhinoscopy were recorded, including odor identification, discrimination and thresholds measured with the "Sniffin' Sticks"-test. RESULTS: CRS influenced olfactory performances variably in the different tests: 10% of the patients had pathologic rates of odor discrimination, compared with 34% in odor identification and 73% in thresholds. Statistical analyses (using Spearman's test) indicated a significant correlation between nasal airflow and odor identification screening (r29 = 0.56, P < 0.01) and n-butanol-threshold (r29 = 0.44, P < 0.05), respectively. CONCLUSION: Olfactory performance in CRS was correlated to several parameters of nasal airflow measured with AAR. The n-butanol threshold test revealed the most frequent pathological results and may best be used for detecting olfactory disorders. However, because a number of factors may influence olfactory dysfunction in CRS, our findings must be evaluated in a lager series.

Adolescent↗

PubMed2000

[Historical development of facial nerve surgery with special reference to hypoglossal-facial nerve anastomosis].

In the ancient times, Aristotle, Herophilos, and Galen discovered basic anatomical structures. Paul von Aegina, in the seventh century A.C., had the idea of a nerve suture, which was first performed in an animal 1000 years later by the Italian surgeon Gabriele Ferrara. Systematic investigations on nerve crossing date to the beginning of the nineteenth century and were conducted by Jean Pierre Flourens. Within 1 week in summer 1864, two French surgeons (Laugier and Nélaton) independently carried out the first nerve sutures in humans. Their observations of an immediate functional recovery of the appropriate muscles after suturing were discussed controversially in scientific circles. The first cross nerve suture of the facial nerve (accessory-facial anastomosis) was first performed by Sir Charles Ballance in 1895. In 1901, the German Werner Koerte was the first surgeon to perform a hypoglossal-facial anastomosis in humans. Surprisingly, the theoretical speculations on the good functional recovery, which was noted after these observations, remain up-to-date.

Anastomosis, Surgical↗