Speech understanding in quiet and in noise with the CIS speech-coding strategy (MED EL Combi-40) compared to the MPEAK and SPEAK strategies (Nucleus).
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Age of Onset↗
Biomedical subjects
J Helms
Publications and source records attributed to J Helms.
Refined mastoid reconstruction with the pedicled postauricular perichondrial flap.
Successful canal wall reconstruction after open cavity surgery may be compromised by both immediate (graft dehiscence and infection) or delayed (graft retraction, absorption, and extrusion) complications. Many of the healing problems following canal wall reconstruction are related to incomplete soft tissue coverage of the graft and limited blood supply. Under these conditions, we sought to increase graft viability with a broad-based perichondrial flap developed from the posterior surface of the auricle. The flap was used over a period of 3 years at a tertiary referral center in 36 cases of canal wall reconstruction in conjunction with composite grafts of cartilage and perichondrium. The patients ranged in age from 12 to 63 years and in all cases had undergone a canal down tympanomastoidectomy that was reconstructed either primarily or secondarily. The canal wall was successfully reconstructed in 35 of 36 ears. These results demonstrate a reduction in our dehiscence rate from 10 to 3% since the introduction of the perichondrial flap. With the perichondrial flap, we were consistently able to achieve better soft tissue coverage of the composite cartilage graft, eliminate lateral graft dehiscence, and encourage reepithelization of the canal. By implication, we believe this flap provides a source of nutritional support for the free cartilage graft as well as the overlying skin.
Adolescent↗
Optimization of channel number and stimulation rate for the fast continuous interleaved sampling strategy in the COMBI 40+.
OBJECTIVE: To investigate the interrelation between number of channels and stimulation rate in the continuous interleaved sampling strategy (CIS). SUBJECTS AND METHODS: Three of the first recipients of the new COMBI 40+ cochlear implant participated in consonant, vowel, number, and sentence tests. Speech understanding was evaluated for different combinations of number of active channels from two to twelve and stimulation rate per channel between 1,515 and 9,090 pulses per second. RESULTS: The results indicate that the optimum number of active channels is not necessarily the maximum number of usable channels.
Adult↗
Effect of estrogen withdrawal on blood pressure and insulin resistance in sucrose-fed juvenile rats.
We have previously shown that juvenile Sprague-Dawley rats, fed a diet in which complex carbohydrates are replaced by sucrose, develop insulin resistance and hypertension. These conditions develop despite the absence of genetic predisposition to either. When studied with the euglycemic hyperinsulinemic clamp technique, these rats have reduced insulin-stimulated glucose utilization, but normal suppression of hepatic glucose output. In the young sucrose-fed rats, it was noted that the degree of blood pressure elevation was greater in males than in females. The purpose of this study was to test the hypothesis that estrogen withdrawal increases insulin resistance and hypertension. Female rats were randomized at weaning (3 weeks of life) to receive control diet or sucrose diet. Animals were assessed with weekly weight and indirect tail-cuff blood pressure. At 8 weeks of life, the sucrose-fed rats were randomized to receive bilateral oophorectomy or sham surgery (anesthesia and uterine horn exposure without removal of the ovaries). At 13 to 14 weeks of life, all animals were fasted overnight, and had an oral glucose tolerance test while conscious. Weight and weight gain were not different among the groups over the 11 week study period. Animals fed the sucrose diet developed significantly higher blood pressure than animals fed the control diet; oophorectomized animals had higher blood pressure than sham-operated animals (P <.0001). Sucrose-fed oophorectomized animals developed fasting and glucose-stimulated hyperinsulinemia. Estrogen withdrawal augments blood pressure in juvenile rats made insulin resistant and hypertensive with a sucrose diet. Estrogen withdrawal in these animals also induces fasting and glucose-stimulated hyperinsulinemia, which are signs of worsening insulin resistance. Androgen:estrogen imbalance increases metabolic dysfunction and worsens hypertension in this animal model.
Animals↗
Ionomeric cement and aluminium encephalopathy.
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Aluminum↗
Retraction pocket/atelectatic middle ear.
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Child↗
[Modern aspects of tympanoplasty. An overview].
The cholesteatoma should be removed with a canal wall down-technique in small mastoids. In patients with well or highly pneumatized temporal bones the reconstruction of the posterior canal wall is recommended after complete removal of the matrix. Myringoplasty is mainly performed using perichondrium. In highly damaged middle ears the cartilage palisade technique is indicated. The reconstruction of the ossicular chain performed using modern artificial materials.
Cholesteatoma, Middle Ear↗
[Facial nerve abnormalities in malformed temporal bone].
Between 1987 and 1993, 4500 tympanoplasties and stapedectomies were performed at the ENT Department of the University of Würzburg. In 134 cases, surgery was performed for malformation of the middle ear. The surgery reports of these patients were analyzed for anomalies of the facial nerve. Forty cases (29.9%) showed an anomaly of the facial nerve, more often congenital aural atresia or major malformation (30.4%) than minor malformation (29.1%). The most frequent finding was a dislocation of the nerve over the oval niche and resulting narrowing of the oval window (22 cases). Eleven cases showed the facial nerve without bony covers, in two cases there was an exposed nerve over the oval niche. An acute-angled course between horizontal and vertical segment in the mastoid, doubling of the nerve, lateralization of the mastoidal segment, and anterior shift of the Fallopian canal in the mastoid were observed once. To reduce the risk of facial nerve injury, high resolution CT scan studies should be performed before surgery in the presence of congenital aural atresia.
Diagnosis, Differential↗
Hearing preservation in acoustic tumor surgery: results and prognostic factors.
A retrospective study was conducted to assess the hearing results in patients who underwent acoustic neuroma removal via the middle fossa approach. A statistical correlation of results with preoperative clinical and audiological data determined if any prognostic indicators could be associated with successful hearing preservation. Of 93 patients included in the study, useful hearing was preserved in 54 (58%), and hearing was preserved near preoperative levels in 42 (45%). The potential for hearing preservation appeared to be inversely related to the size of the acoustic tumor, with hearing preserved in 39 (60%) of 65 patients with tumors less than or equal to 0.5 cm extension into the cerebellopontine angle. Preoperative hearing levels and electronystagmography seemed to have no prognostic value. However, auditory brainstem response showed that a wave V latency of less than 6.8 msec was associated with an increased chance of hearing preservation, and the presence of vertigo as a preoperative complaint appeared to be a good prognostic indicator of successful hearing preservation.
Adult↗
[Microsurgery of large middle ear abnormalities. Technical surgical considerations].
From 1988 to 1994, 75 patients with congenital aural atresias were operated on at the University ENT Department, Würzburg. Sixty-two patients (70 ears) could be followed up in their postoperative outcomes. The surgical approach used in all patients was a direct one through the atresia plate. To avoid infection and stenosis of the new meatus, a neo-tympanic membrane was built up in a far lateral position. This was possible by using a long ossicular prosthesis. The mean postoperative gain was 17.8 dB and the mean postoperative airbone gap was 31.0 dB. Twenty-two percent of the ears had postoperative infections or stenosis of the ear canal. Thirty-four percent of the ears had to undergo revision surgery. Jahrsdoerfer's grading system for congenital aural atresia showed good correlation in 64% of the ears when comparing preoperative status and postoperative outcome.
Adolescent↗
Are implantable hearing devices really necessary?
Indications, advantages and disadvantages of different types of bone-anchored hearing aids and middle ear implants are discussed and compared with conventional hearing devices. The hearing results obtained at the University of Würzburg in 4,195 middle ear surgeries, from January 1988-August 1993, are presented. In those cases where tympanoplasty wasn't able to provide a good hearing result, the additional use of a conventional hearing aid was sufficient. If the gain and maximum output of the implantable hearing aid is improved in the future, the implant may be able to provide intelligible hearing also to patients with a profound sensorineural hearing loss. At this point implantable hearing aids will become really necessary, irreplaceable devices.
Hearing Aids↗
[Detection of DNA of human papillomaviruses (HPV) in an "aggressively" growing cholesteatoma. Is cholesteatoma a virus-induced tumor?].
It is yet unknown why under certain circumstances the benign epithelium covering the outer ear canal in a protective role causes an erosion of bony structures after migration into the middle ear. Histologically, a papillomatous growth and clusters of koilocytes are typical features of the aggressively growing, bone-destructive areas of the cholesteatoma. Since these resemble the characteristics of a papilloma, biopsies originating from cholesteatomas were examined for the presence of human papillomavirus (HPV) DNA. Findings demonstrated that HPV-11-related DNA was present in one such lesion. In general, papilloma viruses need specific conditions to be able to replicate and induce a papillomatous growth. Retraction pockets of epithelium, junction lines between squamous epithelium and mucosa as well as inflammatory processes may stimulate this replication. Because these conditions are characteristic for cholesteatoma, we therefore suggest a possible papillomavirus etiology for the development of aggressive cholesteatoma.
Biopsy↗
Composite autograft "shield" reconstruction of remnant tympanic membranes.
The authors present their combined experience with large cartilage-perichondrial composite grafts used to reconstruct total tympanic membrane perforations in 294 ears. Patients chosen for this procedure had failed earlier tympanoplasty surgery or were identified as poor candidates for conventional facial tympanoplasty because of the perforation size. Successful perforation closure was achieved in 97% of ears with chronic otitis media characterized by absence of the tympanic membrane, including portions of the anterior annular ligament. Hearing results in general were good, considering the advanced stage of the disease, which required the use of alloplastic ossicular prostheses (PORP and TORP) in 76% of ears. Hearing improvement was maximal at 2000 Hz regardless of the method of ossicular reconstruction. Closure of the air-bone gap at this frequency to within 10 dB was achieved in 87% of type I tympanoplasties, 73% of type III (PORP), and 70% of type III (TORP) tympanoplasties. Although cartilage autografts have also been promoted to reverse tympanic membrane atelectasis, the authors believe that the above preoperative conditions are strong indications for this grafting technique, which is described in detail.
Chronic Disease↗
Stapedectomy for congenital fixation of the stapes.
Because several cases of profuse cerebrospinal fluid leakage (perilymph gushers) have been reported during stapedectomy for congenitally fixed stapes in children, many otologists advise against surgical intervention. The pathophysiologic mechanism of perilymph gusher and its association with congenital fixation of the stapes is, however, poorly understood. This retrospective study was designed to examine the preoperative presentation and hearing results of children undergoing stapedectomy for congenital fixation of the stapes. Stapedectomy was performed on 10 ears for this condition. No perilymph gushers or significant sensorineural hearing loss were encountered. All but one case resulted in closure of the air-bone gap at the speech frequencies to within 20 dB, with the average air-bone gap being 11.2 dB. Minor congenital abnormalities of the stapes superstructure were seen in three cases. A review of case reports in the literature would seem to indicate that the perilymph gusher in association with surgical manipulation of the congenitally fixed stapes occurs almost exclusively in males, and that the pathophysiology involves a defect in the internal auditory canal as opposed to a patent cochlear aqueduct. A pre-existing sensorineural hearing loss may also be a risk factor for perilymph gusher.
Adolescent↗
Human-papillomavirus DNA in cholesteatomas.
Cholesteatoma of the middle ear is a relatively common disorder, often with severe consequences. Histologically, the aggressively growing, bone-destructing form shows papillary growth and koilocytosis, which are characteristic of papillomavirus-induced lesions. A PCR (polymerase chain reaction) method using degenerate primers for the detection of any known or as yet unknown HPV (human papillomavirus) type was applied in screening 51 biopsies from 42 patients. A resulting 36% (16/45) of the cholesteatomas were found to contain papillomavirus DNA, which hybridized under stringent conditions with an HPV-II DNA probe. In 3 cases the presence of HPV-II DNA could be confirmed by sequencing the PCR products. The mere presence of this HPV DNA does not prove an etiological role of this group of viruses in the induction of cholesteatomas. It does, however, identify another group of human proliferative lesions putatively linked to papillomavirus infections.
Adolescent↗
Closure of the petrous apex of the temporal bone with ionomeric cement following translabyrinthine removal of an acoustic neuroma.
When performing translabyrinthine surgery for acoustic neuroma, the surgeon opens the cerebrospinal fluid space. To prevent the development of post-operative meningitis, the surgical defect should be closed reliably in a watertight fashion. To date, this has been done with success in 12 patients altogether using a self-curing bone cement (ionomeric cement). During follow-up for a maximum of three years there has been no evidence of cerebrospinal fluid leaks.
Bone Cements↗
[Restoration of sound transmission in the middle ear by reconstruction of the ossicular chain in its physiologic position. Results of incus reconstruction with ionomer cement].
We report the use of an ionomeric based bone substitute to reconstruct the ossicles in their normal position. To reconstruct small defects of the incudo-stapedial joint, this bone replacement material is applied to the long process of the incus and the head of the stapes. After setting and hardening a stable contact to the adjacent bone is formed. The audiological results after reconstruction of small incus defects with ionomeric cement are discussed in comparison to stapedectomy and tympanoplasty.
Adult↗