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Biomedical subjects

J Schipper

Publications and source records attributed to J Schipper.

At least 19 recordsLinked to original sources
PubMed2007

[Navigated "targeted surgery" for skull base malignomas: additional space for surgical manipulation by neoadjuvant tumor downsizing].

BACKGROUND: Multimodal strategies are required due to the poor prognosis for locally advanced frontal skull base tumors staged as T4. Therefore, a further increase in the degree of invalidity caused by therapy should be avoided, if possible, to preserve the quality of life. As the incidence of these tumors is low, there are no evidence-based, generally accepted therapeutic strategies. METHODS: We evaluated the clinical results of three patients with extended frontal skull base malignomas staged as T4 tumors. The clinical course as well as the surgical technique were analyzed. RESULTS: High dose neoadjuvant therapy for tumor downsizing was performed in all three patients within a multimodal therapy concept. The additional space for surgical manipulation close to the tumor borders, non-traumatically produced by tumor remission, permitted a safely navigated, controlled resection of the tumor under endoscopic or microscopic viewing using an approach associated with reduced trauma as "targeted surgery". CONCLUSIONS: Surgical radicality is limited by the direct vicinity of locally progressive T4 tumors to the frontal brain and other vital structures. A controlled tumor downsizing allows the resection of such tumors using a minimally invasive approach assisted by instrumental navigation leading to less traumatization.

Adult↗
PubMed2007

[Posttraumatic amaurosis after complex frontobasal fracture. Differential diagnosis and therapy].

BACKGROUND: Whether surgical nerve decompression is indicated for the treatment of posttraumatic reduced vision with optic nerve compression in the bony canal has been a subject of controversy for decades. On balance, the recent literature suggests that this procedure is indeed indicated, as a supplement to high-dosed cortisone therapy. The risk of surgery-related side effects is usually rated low in the literature. CASE REPORT: We report on a woman patient in whom craniocerebral trauma involved a fracture of the left optic canal with unilateral loss of vision. In the decompression operation, intraoperative symptoms gave rise to the suspicion of an arteriovenous fistula, which had not been revealed by computer tomography and which was seen as sufficient grounds for discontinuing the procedure. In addition to a carotid artery-sinus cavernosus fistula (CCF Barrow type A), subsequent angiography revealed a dissected aneurysm at the branching of the occluded ophthalmic artery. DISCUSSION AND CONCLUSIONS: In decisions on whether surgical relief of pressure on the optic canal is indicated after trauma-related visual loss, the possibility of secondary lesions near the tip of the orbita and the optic canal must be taken into account. These are not always revealed by computer tomography. The indications should be critically weighed up in each individual case, with additional imaging examinations, such as MR-angiography, CT-angiography, or conventional angiography, performed as needed. The options and indications for imaging are discussed. The procedure can by no means be rated as "minimally invasive", as is postulated by some authors.

Adult↗
PubMed2007

[Sonography aided computer assisted surgery (SACAS) in orbital surgery].

BACKGROUND: The application of computer assisted procedures in orbital surgery is made more difficult by the intraoperative tissue shift in intraorbital structures, since this intraoperative dislocation cannot be imaged in preoperative CT/MR datasets. METHODS: After preoperative recording of CT and/or MR datasets in five patients with orbita affected by frontobasal tumors, we used intraoperative sonography by coupling the ultrasound unit to the navigation system. RESULTS: Registration, referencing and calibration of the ultrasound system proceeded without any difficulties. Intraoperatively, the structures of the anterior and middle thirds of the orbita and their tissue shift could be particularly well evaluated sonographically. CONCLUSION: The use of navigated sonography enables repeated intraoperative re-evaluation of preoperative CT/MR datasets. The fusion of intraoperative sonography with preoperative imaging visualizes the tissue shift and facilitates the identification of anatomical structures and the spatial orientation of the surgeon. This appears to allow both increased operative radicality and greater tissue protection. In our opinion, the intraoperative parallel application of a non-calibrated ultrasound system and an only CT/MRT based navigation system cannot fulfill these requirements because of anatomical complexity.

Adult↗
PubMed2006

[Evidence of a novel gene for the LAV-syndrome].

BACKGROUND: Both LAV- (large or enlarged vestibular aqueduct) and Pendred-syndrome are autosomal recessive diseases. In contrast to Pendred-syndrome, LAV-syndrome is characterised only by an enlarged vestibular aqueduct. Pendred-syndrome is a more complex disease. Classically it is characterised by sensorineural hearing loss and enlargement of the thyroid gland. Up to now, only mutations in SLC26A4 gene are known as being responsible for both syndromes. The gene for Pendred-syndrome (SLC26A4) has been localised by linkage analysis of chromosome 7q31. This protein is expressed in the inner ear, thyroid gland, kidney, and placenta. Functional analysis of the gene product (pendrin) in Xenopus laevis oocytes revealed that pendrin acts as an iodide/chloride and chloride/formate exchanger. METHOD: Each of the exons and flanking splice regions of the SLC26A4 gene were analysed by direct sequencing. Haplotype analysis was undertaken with microsatellite markers spanning a 5 Mbp area around the localisation of the SLC26A4 gene. RESULTS: In sequence analysis of 42 patients with bilateral enlargement of the vestibular aqueduct, no mutation could be identified in 30 % of cases. In some of these cases, a linkage to the gene localisation on chromosome 7q31 could not be detected. CONCLUSION: Our results indicate evidence for a second gene involved in the development of LAV-syndrome.

Adolescent↗
PubMed2006

[Craniofacial fibrous dysplasia: scan policy or surgery?].

BACKGROUND: The aetiologic correlations of fibrous dysplasia (FD) are more and more decoded by molecular biology, improved imaging procedures, and the use of computer assisted surgery--thus a review of present diagnostics and therapy methods is evaluated. METHOD: The valid methods of diagnostic and therapy procedures of craniofacial FD were retrospectively analysed in a collective of 9 patients in consideration of literature. The criteria of the decision for diagnosis and surgical procedures were evaluated. RESULTS: According to the literature, diagnosis was ascertained with modern CT and MRI scans. Bone scintigraphy was only used additionally in particular questions. In case of unclear radiological findings histomorphological procedures were used complementarily to distinguish FD from other bone tumors. The aim of surgical intervention was to reduce pain, to restore the function in compression symptoms, to recover original ostia, or to restore the natural geometry of the face. CONCLUSIONS: Current imaging procedures allow differential diagnosis from other benign bone tumors but also from malignancies. The therapy of FD is conservative (wait and scan) or operative in dependence on the localisation, the extension and the clinical manifestations of the disease. In the future molecular biological methods could function as supporting instrument for diagnosis if histomorphological results are not meaningful.

Adult↗
PubMed2006

Rotational tomography of the normal and reconstructed middle ear in temporal bones: an experimental study.

Imaging is an essential diagnostic tool in reconstructive middle ear surgery, especially in pre-operative planning. Due to ongoing improvement of imaging quality and development of new imaging techniques like e.g. rotational tomography (RT) post-operative follow-up and immediate evaluation of surgical results may become more important. The aim of this experimental study was to evaluate RT as a new tool for postoperative determination of middle ear anatomy and implant position in temporal bones. RT was performed in ten temporal bone specimen after insertion of different middle ear prostheses concerning material, shape and length (PORP; TORP; Stapes piston). An implantable hearing device (Symphonix Soundbridge) was also implanted and visualized. For comparison some specimen additionally underwent conventional computed tomography (CT), including the newest technology. Characterization of anatomical structures of the temporal bone using RT was of comparable quality to conventional CT-scans in all investigated specimen while requiring approximately 30% of the CT's irradiation exposure. Unlike CT the RT showed almost no problems due to metallic artefacts of the implanted prostheses. Furthermore RT enabled a 3-dimensional view of the temporal bone and angle determination of inserted prostheses towards the tympanic membrane and/or the malleus handle. Detailed imaging of the prostheses allowed determination of shape, material and localization within the specimen's reconstructed middle ear. The new imaging technique of RT allows precise presentation of anatomical structures and middle ear implants in temporal bones. Following these experimental results it will be our future work to evaluate this method in clinical practise.

Ear, Middle↗
PubMed2006

Prognostic relevance of anamnestic and diagnostic parameters in low-frequency hearing impairment.

Low-frequency hearing impairment (LFHI) is mainly attributed to endolymphatic hydrops and has a great variety of possible outcomes. At present, no conservative therapeutic regimen has proven to be 'gold-standard', and information about the prognostic indicators of LFHI is scarce. In a retrospective investigation, we evaluated the records of 90 patients who had been treated with infusions improving blood perfusion. In patients lacking complete remission, dehydration infusion therapy was added. We also undertook audiometric follow up. We calculated the outcomes after infusion therapy, dehydration therapy and after long-time hearing follow up, and we determined the prognostic relevance of several parameters of anamnesis and clinical examination to outcomes, for both therapeutic interventions and long-time hearing. The prognosis of LFHI was significantly correlated to certain anamnestic and clinical parameters; a short duration of the disease, lack of vertigo and female gender implied a better outcome. The pretherapeutic hearing threshold was an important prognostic factor; the outcome was significantly worse in patients with distinct hearing impairment in low or high frequencies, compared with that in patients with little hearing loss. Whereas vertigo was a negative prognostic factor, the results of quantitative vestibular testing were irrelevant to the outcome. The glycerol test failed to predict the effectiveness of dehydration therapy and lacked any value in predicting prognosis. These results allow the clinician to focus the anamnesis and diagnostic examination on prognostically relevant parameters, thus enabling a better estimation of the long-term disease course and improved counselling of patients. Furthermore, these results help to distinguish valuable from irrelevant diagnostic procedures.

Acetazolamide↗
PubMed2006

[Cochlear protection and surgical precision in stapedotomy with Er:YAG laser].

BACKGROUND: Using laser in stapedotomy has attracted a lot of attention since the nineties. It aims at minimizing complications due to hand-operated equipment, especially inner ear lesions, and achieving higher precision. We analyzed the clinical effect of Er:YAG laser with the question whether the postulated cochlea protection and foot plate perforation, optimized for better sound conduction, are achieved, compared to conventional stapedotomy. PATIENTS AND METHODS: We evaluated retrospectively audiometrical data including pre- and postoperative bone and air conduction thresholds of 114 consecutive patients, on whom we had performed stapedotomy and had inserted platinum-teflon prostheses. The intervention was done conventionally in 72 cases and in 42 cases with Er:YAG laser. RESULTS: In the lower and middle frequencies, laser technique resulted in a more pronounced improvement of bone conduction thresholds compared to conventional stapedotomy. The improvement of air conduction was more distinct in ears after laser surgery; also, the difference between air and bone conduction was reduced at a higher degree. CONCLUSION: Er:YAG laser in stapedotomy is coupled with cochlea protection, as demonstrated under clinical conditions, and allows higher hearing benefit of air conduction compared to conventional stapedotomy. Our results emphasize the impact of innovative laser technique on stapedotomy.

Adult↗
PubMed2006

[The transverse rectus abdominis muscle (TRAM) flap. A "second defensive line" in microvascular reconstructions of defects in the head and neck area].

BACKGROUND: The microvascular anastomosed transverse rectus abdominis muscle (TRAM) island flap has been successfully used in plastic surgery for more than 10 years. In reconstructive head and neck surgery, however, it is not yet established. METHOD: We analysed the preparation and anatomical variation in TRAM flaps in an examination of eight cadavers. In a clinical case with complete reconstruction of the nose after nasal ablation and complete loss of a radial lower forearm flap that had been transplanted previously due to a recurrent tumor, the possibility of forming and modeling a TRAM flap is demonstrated. RESULTS: The flap vessels of the TRAM are comparable to the radial forearm flap, and the donor site may be primarily closed. The TRAM proved to be a suitable alternative to close lesions of the head and neck area in selected cases. The myocutaneous TRAM is bulkier than the fascio-cutaneous radial forearm flap. The subcutaneous abdominal fat of the TRAM can be reduced in relation to the vascular distribution of the perforator vessels. If the subcutaneous fat of the flap is reduced, the flap can be shaped and formed well. In the described case, it was used to close the lesion after ablation of the nose and middle face. CONCLUSION: The risk of an iatrogenic lesion of the peritoneal fascia or postsurgical herniation of the abdominal wall is low if several surgical prerequisites are taken into consideration. The myocutaneous TRAM will not replace the fascio-cutaneous radial forearm flap in microvascular head and neck surgery, but the large diameter of the donor vessels and the highly vascularized flap tissue makes it an alternative as a second line procedure in cases of unfavorable wound conditions.

Cadaver↗
PubMed2006

[Skull base chondrosarcoma. An interdisciplinary challenge].

BACKGROUND: Chondrosarcoma is a rare differential diagnosis of malignant tumours of the skull base. The prognosis was rated as unfavourable in articles for many years. It has, however, improved considerably in recent years. The objective of this study was to evaluate and current, new optimised treatment strategies. PATIENTS AND METHODS: We retrospectively analysed the case histories and course of four patients whom we treated for chondrosarcoma of the skull base over the past 5 years at the Freiburg Skull Base Centre. RESULTS: Because of initially mild symptoms, the patients first came for examination at an advanced stage of the tumour. All patients underwent surgery, whereby an R0-resection was barely or only questionably present. Three patients underwent radiation therapy postoperatively. All patients are currently tumour free. CONCLUSIONS: Surgical treatment with curative intent is basically the therapy of choice. Due to the usually large size of the tumour and its close relationship to relevant structures, complete resection is, however, not always possible despite advances in surgical procedures. Taking the possibility of modern adjuvant radiotherapeutic procedures into account, an incomplete, function-preserving resection is preferred to a radical and mutilating resection.

Adult↗
PubMed2006

[Objectivity of therapeutic results following skull base surgery using virtual model analysis].

BACKGROUND: Virtual model analysis of patient head tracking allows for objectivity and the monitoring of therapeutic results of pathologies in the skull base region. The introduction of these models in clinical routine has been impaired by the extended time needed for the preparation of radiological data. METHODS: Quality control analysis was carried out for seven cases with different pathological findings in the skull base region in patients who had undergone virtual model analysis. RESULTS: Preparation time of radiological data for the process of segmentation required, under optimal conditions, a minimum of 30 min. Virtual model analysis enables spatial visualization of regions of interest and adjacent anatomical structures. This improves case-specific pathoanatomical understanding as well as preoperative planning of surgical strategies. CONCLUSIONS: Virtual model analysis improves the physician's spatial comprehension of localized pathological findings at the dysmorphic interface of bone and soft tissue across the skull base. Therefore, it seems to be an adequate tool for quality control analysis of therapeutic results after extended skull base surgery.

Adolescent↗
PubMed2006

[Single and temporally displaced second nerve lesions in an animal model and their clinical significance].

BACKGROUND: Surgical optic decompression after trauma has been discussed controversially. The surgical trauma is supposed to produce an additional nerve lesion with the danger of complete loss of vision. Alternatively, conservative high dose cortisone therapy has been recommended. METHODS: The functional and morphological consequences of a lesion after calibrated optic compression in one or two sessions were examined in an animal model using 29 Wistar rats. RESULTS: Depending on the duration and intensity of the lesion, we observed a linear decline in the number of neurons in the RGC (retinal ganglion cell) layer as well as an increasing reactivity to GFAP (glial fibrillary acidic protein) as an indication of central gliosis of astrocytes; however, this was independent on whether optic compression was performed in one or two sessions. CONCLUSIONS: To reduce secondary damage to the visual nerve and the central visual system that might increase with a persisting lesion, the indication for surgical relief of an eye affected by afference should be considered liberally, especially in view of the low morbidity of rhinosurgical intervention.

Animals↗
PubMed2006

[Pseudodominants of two recessive connexin mutations in non-syndromic sensorineural hearing loss?].

BACKGROUND: Hitherto more than hundred genes and gene loci for non-syndromic or syndromic deafness have been identified. Mutations in the connexin 26 gene (GJB2) account for up to 50 % of the cases of autosomal recessive hearing loss. The genes GJB2 (Connexin 26), GJB3 (connexin 31) and GJB6 (connexin 31) are located on chromosome 13q11-12. In the inner ear up to four different connexins are expressed. Connexins appertain to a group of gap junction proteins. These proteins can oligomerize to form single-membrane channels called connexons. Each connexon is composed of six subunits, that allow communication between adjacent cells by providing a channel for diffusion of ions, metabolites and second messengers. METHOD: Each of the exons and flanking splice regions of the connexin 26, 30, and 31 genes (GJB2, GJB3, and GJB6) have been analysed by direct sequencing. RESULTS: In the involved families three heterozygous mutations could be detected in the connexin 26 (GJB2) and connexin 30 (GJB6) genes. If a combination of two of those mutations occurs, 35DeltaG with 146/147DeltaC and 35DeltaG with GJB6-D13S1830 it results in hearing loss and deafness. CONCLUSION: By evidences of a familial background of hearing loss it is reasonable to analyse the connexin genes (GJB2, GJB3 and GJB6) for mutations, additionally to a specific hearing diagnostic, in order to enhance linguistic development through hearing aid or CI-implantation at an early stage.

Adult↗
PubMed2006

[Ethisorb/Ethisorb durapatch for the transnasal duraplasty procedure?].

BACKGROUND: Defects of the dura in the rhinobasal area can be closed transnasally. Various procedures with autologous or alloplastic material can be chosen. METHOD: From 2001 to 2004, we closed a rhinobasal dura defect with Ethisorb or Ethisorb durapatch in sandwich technique in 8 patients. After smoothing the bone edges, Ethisorb is applied under microscopic or endoscopic view endocranially, extradurally as "underlay" to seal and absorb the liquor pressure pillar. Additionally, another Ethisorb implant as "underlay" is applied extracranially from endonasally as "underlay", and sealed with a further layer of nasal concha mucosa with fibrin glue. RESULTS: All patients were successfully treated with this technique. There were no evidences for persisting rhinoliquorrhoe after the period of wound healing. For hemostasia, a nasal package was applied for compression at the donor site of the inferior nasal concha. The former dura defect was at all times freely accessible in order to be able to recognize a possible new rhinoliquorrhoea early and to prevent a possible congestive secretion with superinfection. DISCUSSION: The material of Ethisorb and Ethisorb durapatch is stiff and can be easily modelled, so it is an alternative as an alloplastic material for endonasal closure of defined substantial defects of the dura with rhinoliquorrhoe.

Adult↗
PubMed2006

[Multidisciplinary management of skull base and craniocervical chordoma].

BACKGROUND: Craniocervical chordomas often only become manifest in an advanced stage. The localisation and locally-destructive growth require a multidisciplinary diagnostic and therapeutic concept early on. The goal of the present study was to present a reproducible strategy for quality assurance. PATIENTS AND METHOD: We retrospectively analysed the hospital records of 10 consecutive patients (4 women and 6 men) whom we had treated during a period of 7 years. RESULTS: The first step in therapy was tumour resection in 9 cases. One patient initially underwent stereotactic radiation. Postoperative radiation was not included a priori, but discussed individually depending on the degree of resection, the patient's age and physical condition. After an average 5 years follow up, 100 % of patients are alive. In all patients, tumour control was achieved. CONCLUSIONS: The prognosis for patients with chordomas of the skull base has improved considerably in recent years. New technologies like intraoperative navigation and improved radiation procedures have contributed to this improvement. The basis for treatment remains, however, the greatest possible surgical exstirpation with minimal surgical morbidity. Special attention should be paid in this connection to the stability of the cervical spine and the craniocervical transition border. In advanced tumour growth, complete resection is often not possible. Proton and heavy-ion radiation are promising new forms of therapy, which can also be applied after conventional radiation has been performed. A directed multidisciplinary procedure guarantees years of survival with good quality of life in many cases.

Adult↗
PubMed2006

[Reconstruction of tumor induced defects in head and neck surgery with individualized prefabricated three dimensional flaps with the use of continuous vacuum therapy].

Despite recent developments in oncologic head and neck surgery extensive tissue and functional defects following radical tumor resections remains a surgical challenge. Individually prefabricated free flaps to meet the needs of the functional defect can be generated with the help of continuous computer-assisted vacuum therapy. This accelerates the pre-fabrication of three-dimensional composite flaps and enhances therapeutic safety. Changes of the genuine structure of such flaps are induced by implantation of autologous or heterologous transplants alone or in combination with alloplastic materials as a supportive element. Application of vacuum therapy is useful to accelerate the process of pre-fabrication by the induction of angiogenesis. Besides this the continuous removal of wound exudate, possible seroma or haematoma and secondary compression of the different tissue layers improve the modelling of the three-dimensional construct. This article describes the technique of vacuum therapy for the pre-fabrication of three-dimensional pedicled or free flaps for reconstruction of defects after tumor resection in the head and neck area.

Absorbable Implants↗
PubMed2005

The free vastus lateralis flap for reconstruction in ablative oncologic head and neck surgery.

AIMS: The vastus lateralis muscle is an accessory extensor for the knee suitable as a free myocutaneous flap in reconstructive head and neck surgery. We report the use of this muscle as a flap. METHODS: We have used the free myocutaneous vastus lateralis flap for reconstruction following ablative head and neck tumour surgery in six patients. The clinical outcome, time of surgery for flap preparation and anatomosis, follow-up and functional outcome were analysed. RESULTS: Five of our patients showed a very satisfactory functional and cosmetic outcome. Post-operatively, there was no prolonged immobilisation and no limitation of movement to the hip and knee. No unfavourable side-effects at the donor side were noted. CONCLUSIONS: We find this flap a very useful addition to our free myocutaneous flap armamentarium. It has a specific suitability for replacing large defects.

Aged↗