[Diagnostic value of color Doppler ultrasound diagnosis].
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Blood Flow Velocity↗
Biomedical subjects
P R Issing
Publications and source records attributed to P R Issing.
[Pyoderma gangraenosum. Case report and comparison with necrotizing fasciitis].
The differential diagnosis of patients with ulcerative trachelophyma repeatedly causes difficulties. Particularly in view of the possibly fatal outcome, early differentiation between two clinical pictures is very important. Necrotizing fasciitis is often misdiagnosed or the diagnosis is delayed with a mortality rate of approximately 25-40%. It is characterized by local disintegration of the subcutaneous fascia and extensive gangrene of the skin. Sometimes it is not even possible to control the disease using combined antibiotics. Early surgical exploration is mandatory to stop progression of the disease. Pyoderma gangrenosum develops following an initial lesion with pustules and bullae in an ulceration with slight bleeding. Therapy consists of i.v. glucocorticoids (60-200 mg prednisolone/day) administered as early as possible. In complete contrast to the therapy for necrotizing fasciitis, surgical intervention should be strictly avoided in cases of pyoderma gangrenosum.
Adult↗
[Long term results in adenoidcystic carcinoma].
BACKGROUND: Due to the discreet initial symptoms and the locally aggressive infiltration with perineural spread the adenoidcystic carcinoma (ACC) presents a special diagnostical and therapeutical challenge. PATIENTS: : In a retrospective study the forms of 54 patients were analysed, whose average age was 55.5 (24 - 77) years. RESULTS: The sex ratio showed a slight female preponderance with 57 % to 43 %. The major salivary glands were affected in 26 cases. The exact distribution of the ACC was: parotid gland (n = 18), submandibular gland (n = 8), oral cavity (n = 10), paranasal sinuses (n = 11), nasopharynx (n = 4) and larynx (n = 3). The most common symptoms were a tumor-related swelling and pain which persisted for a duration of several months after final diagnosis could be established. Facial palsy was observed in 4 patients. Histological examination revealed a tubular subtype in 4 cases, in 28 cases a cribriforme and in 12 cases a solid subtype. No definitive differentiation was possible in 10 specimens. The skull base was infiltrated in 16 patients. Except one patient all 54 underwent surgical therapy. Postoperative radiotherapy was additionally given in 25 cases which was combined with a chemotherapy in 6 patients. Nevertheless ACC recurred in 60 % of our patients. Lymphnode metastases were observed in 13 patients after a latency of 3.3 years in average, but predominantly pulmonary metastases as distant spread developed in 18 patients after 5.8 years significantly later. The overall survival rate was 84.38 % after 2 years, 75.90 % after 5 years, 50.49 % after 10 years and 20.11 % after 20 years. Male sex, infiltration of the skull base and histological evidence of perineural and perivascular spread proved to be statistically significant factors for an unfavourable prognosis. CONCLUSIONS: Due to the uncommon biological behaviour with a slow growth on the one hand side and an aggressive local invasion on the other hand side the ACC can be regarded as a challenging malignant disease for the clinician whose adequate therapy does not allow any standardized regime. The tendency for recurrence even after a period clinically free of symptoms makes a life long follow-up mandatory.
Adult↗
[Application of Optical Coherence Tomography (OCT) in middle ear surgery].
BACKGROUND: Middle ear surgery has reached an advanced stage of development over the last few decades. The use of biocompatible materials offers new possibilities in ossiculoplasty. The exact calculation concerning the length of the implant to be used, however, still poses considerable difficulties and is an additional cause for a remaining air conduction difference or a further surgical intervention. METHODS: Optical coherence tomography (OCT) is a non-invasive imaging procedure for the imaging of tissue structures with a resolution accurate to micrometres. OCT can be operated touch-free and for this reason does not require any means of contact between applicator and sample. In the present study an optical coherence inferometre was coupled to an operating microscope and used in 5 stapedoplasties and 5 tympanoplasties type III in order to determine the length of the prosthesis to be used. RESULTS: The use of OCT implies an intraoperative measuring time of only a few seconds. The coupling in the optical path of an operating microscope allows trouble-free handling. The measurement of middle ear structures has an accuracy of 30 micrometer. The postoperative audiological results show a good auditory performance. CONCLUSIONS: Initial experience with OCT indicates that the technology will be extremely interesting for otosurgery. Improvements in functional pattern will enable routine intervention in connection with an operating microscope. Further OCT applications for tissue differentiation will have to follow.
Equipment Design↗
[Skull base surgery with an opto-electronic navigation system].
BACKGROUND AND OBJECTIVE: The exact localization of pathological anatomy is the basis of a successful operation. Malformations, tumors, or previous operations can make intraoperative orientation considerably more difficult. Navigation systems can be useful tools in such cases. METHODS: The OTS is an optoelectrical navigation system which was used on 34 patients with disorders of the skull base region. Clinical accuracy, practicability, and intraoperative usefulness of the system were evaluated. RESULTS: In clinical use, an accuracy of approximately 1.5 mm could only be achieved with the use of head fixation and bone-anchored reference markers. When using the VBH mouthpiece for dynamic referencing with flexible head positioning, deviations of less than 2 mm were observed. The preoperative preparation time was 15-25 min, depending on the operation schedule. CONCLUSIONS: The intraoperative orientation system represents a significant aid for orientation, particularly where anatomical alterations are present. Further modifications to improve both accuracy and the integration of the system into working practice are, however, essential.
Adult↗
[Vibrant Sound Bridge System. A new kind hearing prosthesis for patients with sensorineural hearing loss. 2. Audiological results].
OBJECTIVE: Implantable hearing aids present a new treatment modality for patients suffering from sensorineural hearing loss. The functional gain obtained with the partially implantable Symphonix soundbridge system was evaluated in a clinical study. The audiological results achieved with n = 34 patients over a period of up to three years are presented in this second part of the publication. PATIENTS AND METHODS: 34 patients have received the Symphonix Vibrant soundbridge system since February 1997. The average age at implantation was 47.2 years (minimum: 18.9 years; maximum: 80.3 years). All patients have had several years of experience with hearing aids, which, however, provided insufficient functional gain or could not be fitted with a conventional hearing aid for medical reasons (such as auditory ear canal problems). All patients fulfilled the audiological selection criteria as they had bilateral moderate to severe sensorineural hearing loss. As a rule, the ear with poorer performance was implanted. All patients were fitted with the audio processor eight weeks after the implantation. The pure tone thresholds, the functional gain, the monosyllable and sentence understanding (Göttinger Sentence Test in quiet and noise) were preoperatively and postoperatively assessed. Standardized self-assessment questionnaires were used to evaluate the subjective benefit (PHAB) and the quality of hearing (HDSS) as compared to the preoperative situation. Further hearing tests were performed after four weeks, three, six, nine, twelve, eighteen, twenty-four and thirty-six months postoperatively. During the observation period of up to three years the audioprocessor was updated several times, most recently with the fully digital three-channel-system Vibrant D. The results obtained were documented. RESULTS: Postoperatively, the pure tone threshold with the soundbridge system switched off did not change significantly in the implanted ear. All patients had a functional gain that was either comparable to the gain achieved with hearing aids or better. In particular speech-related frequencies showed improved amplification. The free field speech recognition tests revealed higher scores in quiet and in noise. The patients commended the natural sound quality, the lack of feedback, the absence of occlusion and distortion, the improved speech understanding in noise and the favourable cosmetic appeal. Only two patients failed to achieve better results as compared to their performance with conventional hearing aids. No complications, such as a deterioration of hearing due to inner ear damage or a conductive hearing loss, were observed in the long-term. CONCLUSIONS: The Symphonix Vibrant Soundbridge is a new and promising treatment modality for patients suffering from moderate to severe sensorineural hearing loss. Further improvement of the good results can be expected with improved coupling of the transducer to the ossicular chain and further development of signal processing.
Adolescent↗
[CAS-System MKM(R): use and results in lateral skull base surgery].
BACKGROUND: Computer assisted surgery has reached an advanced stage of development and offers new possibilities in daily surgical procedures. METHODS: The MKM(R) - is a navigation system fitted with a laser-guided, autofocus-microscope for referencing purposes. The coordinates can be set using various marker systems and a special workstation is used for preoperative planning. It is possible to add landmarks and display them in the surgeon's eyepiece. The clinical integration, the time required for the use of the navigation system and the intraoperative accuracy of the system were evaluated on the basis of 136 lateral skull base procedures. RESULTS: The degree of accuracy is determined by the type, amount and positioning of markers. The adjustment of reference points should be carried out following macrosurgery in order to avoid shifting factors. For an additional increase in accuracy, an improvement in the spatial resolution of the CT scans is required, with a section thickness of 1 mm and a pixel size of 0.5mm. The bone-anchored structures of the temporal bone do not underlie shifting or extensive intraoperative swelling. Skull base surgery is, therefore, ideally suited for the application of CAS. We found that registration was accurate to less than 1 mm (0.68 mm +/- 0.17 mm) and that the MKM(R) system made an additional contribution to surgical safety by identifying important structures. CONCLUSIONS: A practical accuracy found to be approximately one millimetre suggests that the non-invasive referencing system may be effective, accurate and useful for computer assisted identification of vital structures. We expect navigation systems to improve the quality and reduce the risks of surgical intraventions.
Adult↗
The nucleus double array cochlear implant: a new concept for the obliterated cochlea.
OBJECTIVE: To increase the number of intracochlear electrodes that may be inserted into a totally obliterated cochlea, a special implant has been developed in collaboration with Cochlear Limited. This implant features two separate electrode carriers containing 11 and 10 active electrodes, respectively, as well as a reference electrode located on the receiver-stimulator package. The potential stimulation modes available with this device therefore include monopolar and bipolar stimulation, and stimulation between both arrays. SURGICAL TECHNIQUE: A cochleostomy anterior to the round window provides access to the basal turn (both the scala tympani and the scala vestibuli), and new built connective tissue and bone can be removed until the anterior wall of the basal turn is approached. A second cochleostomy is performed at the second turn caudal of the cochleariform process and 2 mm anterior of the oval window after removal of the incus. New tissue should also be removed if necessary. The two electrode carriers are then placed into the scala tympani of the basal and the scala vestibuli of the second turn, respectively. The remaining surgical procedure is identical with that used for cochlear implantation in patients without obliterated cochleas. PATIENTS: In this clinical study, 10 patients aged 32 to 66 years with an obliterated cochlea each received a double array cochlear implant. All patients had total obliteration of the basal turn either on preoperative imaging or during surgery. Intraoperatively, the second turn was not obliterated in only 4 of 10 patients. Postoperatively, a standard audiologic test battery was used to determine auditory improvement over time. POSTOPERATIVE RESULTS: All patients achieved significantly improved speech understanding when the additional apical electrode array was used, compared with the use of each electrode array independently. No complications occurred. CONCLUSION: In patients with a totally obliterated cochlea, the number of intracochlear electrodes can be increased by use of the Nucleus double array implant. As a result, patients achieve significantly better auditory results.
Adult↗
Image-guided surgery of the anterior skull base.
Minimally invasive surgical procedures have revolutionized surgery of the paranasal sinuses. The endonasal procedure has become standard practice due to a better understanding of pathological physiology. However, malformations, previous operations and bleeding can interfere greatly with intraoperative orientation. Together with microscopy and endoscopy, image-guided surgery has the potential to be of significant assistance to the surgeon. We evaluated the electromagnetic navigation system InstaTrak 2000 (Visualization Technologies Inc., Lawrence, MA) in 168 patients with various disorders of the paranasal sinuses who underwent endonasal surgery. The system consists of a headset attached to an electronic transmitter which is fitted on the dorsum of the nose and in the external auditory canal. With the aid of low-frequency magnetic fields the position of the instrument equipped with an electromagnetic receiver is calculated on the basis of the reaction of ferromagnetic components in the magnetic field; the location is displayed in orthogonal sections on a high resolution screen. The intraoperative accuracy of the system was estimated to be 1.2-2.8 mm. The preparation time amounted to < 10 min. No system failures were observed. The InstaTrak 2000 navigation system is only suitable for endonasal surgery. The placement of the electromagnetic transmitter and receiver allows flexible head positioning through the use of a headset. This system is a valuable aid for the surgeon under anatomically complex conditions. The technology also lends itself well to training purposes, as visualization in different sectional planes augments the understanding of anatomy and pathological anatomy.
Adult↗
A silastic positioner for a modiolus-hugging position of intracochlear electrodes: electrophysiologic effects.
HYPOTHESIS: It was postulated that an electrode array that achieved a close modiolar proximity would result in reduced threshold levels and amplitude slopes, as measured with electrically evoked auditory brainstem responses (EABRs). BACKGROUND: Quality and quantity of auditory information transmitted by a cochlear implant to patients with sensorineural hearing loss depend on spatial and temporal resolution achieved by the electrical intracochlear stimulation. METHODS: To improve spatial resolution, a new electrode system was developed by Advanced Bionics Corp., with the intention of obtaining greater modiolar proximity. The implant version specified for animal experiments consists of a straight electrode array of seven embedded platinum discs and a so-called Silastic-positioner. The Silastic positioner is shaped to follow the dimensions of the scala tympani with a concave (triangular) inner side, which fits the form of the electrode array. The aim of the study was to evaluate the influence of a modiolus-hugging electrode position in contrast to a conventional electrode position on EABR in short-term animal experiments. Short-term electrophysiologic studies were performed on six adult cats. After local intracochlear application of neomycin solution (50 mg/mL), electrodes were inserted into the scala tympani. Electrically evoked auditory brainstem response threshold levels and EABR amplitude slopes were systematically investigated with and without the positioner. RESULTS: Electrically evoked auditory brainstem response measurements revealed a distinct apicobasal threshold shift, with increasing thresholds toward the basal end of the electrode. After insertion of the positioner, this shift diminished or was inverted and EABR thresholds and amplitude slopes were reduced significantly. CONCLUSIONS: Threshold and amplitude slope data emphasize the functional benefit of the positioner system, especially for the stimulation of electrodes in the more basal channels.
Animals↗
Pathology case of the month. Usher's syndrome.
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Aged↗
[Possibilities and limits of Doppler ultrasound in the area of the head-neck].
Sonography has provided an important addition to the tools available for the diagnosis of the soft tissues in the head and neck region. The ENT surgeon himself is able to examine pathological formations by this quick, non-invasive and, last but not least, less expensive method. Due to the high resolution of the procedure the chance of detecting even small changes is increased and the exactness of diagnosis of pathological lymph nodes of the neck has been significantly improved compared to palpation alone. Ultrasound has replaced the sialographic procedures in the field of diagnostic evaluation of salivary gland disease in the daily practice except for special indications. After inauguration of color Doppler sonography non-invasive evaluation of vascular stenosis of the large cervical vessels concerning their hemodynamic effects has become possible. This issue is important for the differential diagnosis of otoneurological diseases such as sudden hearing loss, vertigo and tinnitus. Additionally, the extent of perfusion of space-occupying lesions can be easily examined, and therefore the risk of mass bleeding can be preoperatively assessed by this method without harm to the patient. Especially carotid body tumors may be diagnosed with high accuracy by the evidence of significant diffuse perfusion of the lesion. In several studies the specificity of the assessment of cervical lymph node disease could be increased by examination of resistance indices. However, other authors have shown inconsistent results in differentiation of benign and malignant lumps; therefore, final judgment does not seem to be possible yet. Use of echo-contrast agents to enhance the ultrasound signal seems to be a promising approach for future developments in color Doppler imaging.
Humans↗
[Throat pain after chopping wood. Penetrating trauma of the soft tissues of the neck caused by a metal splinter].
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Adult↗
[Sonographic diagnosis of metastatic renal cell carcinoma to the head and neck region].
In the area of the head and neck metastases from distant primary tumours are rare in comparison to the common squamous cell carcinomas of the upper respiratory and digestive tract. Thus correct preoperative diagnosis may be difficult. Two cases with distant metastases of renal cell carcinoma to the head and neck region are presented in this report. In a 60-year-old male patient, diagnostic evaluation of unilateral epistaxis revealed a radioopacity of the maxillary sinus, six months after removal of a renal cell carcinoma. In the second case a slowly progressive indolent swelling of the left neck developed in a 56-year-old man six years after resection of a renal cell carcinoma and two years after surgical treatment of a pancreatic carcinoma. Following clinical examination, modern imaging techniques with special emphasis on colour Doppler sonography with a Siemens Quantum 2000 were used for diagnostic evaluation in both patients. Sonography of metastatic renal cell carcinoma to the maxillary sinus revealed complete opacity of the antrum. The cervical mass proved to the inhomogeneous and hypoechogenic and was difficult to distinguish from the lower parotid lobe and the vessel sheath. A common feature of both tumours was a high degree of perfusion which could be confirmed by superselective angiography. The histological examination of the surgical specimen showed an isolated metastasis of a renal cell carcinoma in both cases. In patients with a history of renal cell carcinoma the possibility of distant spread to the head and neck region should be taken into account even after a long period of complete remission. Colour Doppler sonography facilitates the distinction between the normally well perfused secondary tumours and squamous cell carcinomas which usually only have a minimal blood supply. Because of the high risk of profuse bleeding a biopsy should only be performed in the operating theatre.
Carcinoma, Renal Cell↗
[Ultrasound evaluation of characteristics of cervical lymph nodes with special reference to color Doppler ultrasound. A contribution to differentiating reactive from metastatic lymph node involvement in the neck].
BACKGROUND: Cervical mass due to lymphadenopathy is a common cause for consultation of an ENT specialist by patients. In many cases exact differentiation without biopsy between reactive and metastatic lymphnodes is difficult but crucial and necessary for each patient. Ultrasound is the imaging system with the highest sensitivity for the evaluation of pathological lymph nodes. However, differentiating benign and malignant lesions remains a problem. PATIENTS: In a prospective study, 138 cervical lymph nodes of 62 patients were evaluated according to conventional ultrasound criteria such as size, shape, brightness, demarcation, etc., and according to parameters of color doppler sonography such as intensity and localization of perfusion. The so called Pourcelot or resistance index, an objective parameter, was measured in order to examine a possible improvement of specificity in differential diagnosis of both entities. All lymph nodes were surgically removed and histologically examined after ultrasonography. RESULTS: 133 lymph nodes were evaluated in the study. Lymphadenitis was demonstrated in 72 cases, whereas 61 of the lumps showed metastases of squamous cell carcinoma of the head and neck region. Three patients with primary malignant lymphoma were excluded from the study. The conventional ultrasound parameters such as size, homogenity, shape and brightness did not reveal any substantial difference between the two groups. However, lymph node metastases significantly showed higher Doppler signals than the reactive ones. Most of the metastases were perfused in the periphery or had a diffuse spread of blood flow. The most valuable parameter from the prognostical point of view proved to be the Pourcelot Index with a threshold value less than 0.6 for metastases, which increased the specificity to 92% with a probability of p = 0.001. CONCLUSIONS: The results of this study demonstrate an increase of the ultrasound specificity in differentiation of pathological cervical lymph nodes using color flow imaging. Unfortunately, this method does not enable the physician to correctly diagnose the findings in all patients. Therefore histological evaluation is mandatory in all doubtful cases.
Adolescent↗
[Monthly interesting case no. 21. Plasmocytoma at the base of the skull (Kieler classification: plasmacytic non-Hodgkin's lymphoma)].
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Aged↗
[Bilateral basal cell adenoma of the parotid gland and miltiple cylindromas of the skin--is there a syndromal coincidence?].
BACKGROUND: Compared to the typical carcinomas of the upper aerodigestive tract the benign tumours of the salivary glands show significant histological diversity. Therefore correct histological diagnosis might be difficult even for the pathologist. Basal cell adenoma may have a multifocal origin and can be associated with cylindromas of the skin. PATIENTS: In 17 patients with an average age of 65.8 a basal cell adenoma of a major salivary gland was diagnosed with a slight preponderance of the female sex (10:7). RESULTS: One male patient showed a bilateral basal cell adenoma of the parotid gland and simultaneously multiple cylindromas of the skin in the head and neck region. There might be a syndromal coincidence, since histology revealed similar features of the salivary gland tumours compared to the skin neoplasias. The patient's history gave hints of a familial occurrence of the dermal cylindromas. CONCLUSIONS: In rare cases a basal cell adenoma of the dermal type may be associated with cylindromas of the skin suggesting a common histogenesis. Due to possible multifocal origin and the menacing risk of malignant transformation a thorough follow-up of the patients after surgical treatment is mandatory.
Adenoma↗
Expression pattern of the plasminogen activator-plasmin system in human cholesteatoma.
The plasminogen activator-plasmin system plays a pivotal role in the delicately regulated process of extracellular matrix remodeling. Recent studies have shown that an imbalance of proteolytic enzymes over specific inhibitors in this system may lead to an aggressive, expanding, and infiltrating cellular phenotype. As cholesteatoma resembles a tumor in many ways, we investigated the pattern of expression for members of the plasminogen activator-plasmin system in 12 human cholesteatomas, using immunohistochemistry. As controls, 3 tympanic membranes and 4 ear canal skin specimens were used. In contrast to the tympanic membranes, all cholesteatoma specimens showed a strong expression of plasminogen at the basal epithelial cell layers. In ear canal skin, only the basal surface of the most basal epithelia stained discretely positive. The urokinase-type plasminogen activator (uPA) could be detected in the basal stratum of the cholesteatoma matrix and in the surrounding granulation tissue, while tissue-type plasminogen activator (tPA) was not detectable at all. Plasminogen activator inhibitor-1 (PAI-1) was expressed in both the granulation tissue and the granular cell layer of the matrix, but not in the basal epithelial cells; PAI-2 showed a pericellular expression pattern in the subbasal and granular cell layers. Neither uPA, tPA, nor the PAIs could be detected in tympanic membrane controls; ear canal skin showed the same staining pattern as cholesteatoma only for PAI-2. Our data demonstrate that there is a clear imbalance in favor of proteolytic activity in the basal epithelial layers of the cholesteatoma matrix, which might at least partly account for the aggressive behavior of this tumorlike lesion. Further, the pattern of expression resembles the pattern described for several epithelial malignancies.
Cholesteatoma, Middle Ear↗