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Dive into the research topics where John L. Dornhoffer is active.

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Featured researches published by John L. Dornhoffer.


Laryngoscope | 2010

Cartilage tympanoplasty: Indications, techniques, and outcomes in A 1,000-patient series

John L. Dornhoffer

Objectives/Hypothesis: The purpose of this study was to analyze the anatomical and audiologic results in more than 1,000 cartilage tympanoplasties that utilized a logical application of several techniques for the management of the difficult ear (cholesteatoma, recurrent perforation, atelectasis). Our hypothesis was that pathology and status of the ossicular chain should dictate the technique used to achieve optimal outcome. Study Design: Retrospective clinical study of patients undergoing cartilage tympanoplasty between July 1994 and July 2001. A computerized otologic database and patient charts were used to obtain the necessary data. Methods: A modification of the perichondrium/cartilage island flap was utilized for tympanic membrane reconstruction in cases of the atelectatic ear, for high‐risk perforation in the presence of an intact ossicular chain, and in association with ossiculoplasty when the malleus was absent. A modification of the palisade technique was utilized for TM reconstruction in cases of cholesteatoma and in association with ossiculoplasty when the malleus was present. Hearing results were reported using a four‐frequency (500, 1,000, 2,000, 3,000 Hz) pure‐tone average air‐bone gap (PTA‐ABG). The Student t test was used for statistical comparison. Postoperative complications were recorded. Results: During the study period, cartilage was used for TM reconstruction in more than 1,000 patients, of which 712 had sufficient data available for inclusion. Of these, 636 were available for outcomes analysis. In 220 cholesteatoma cases, the average pre‐ and postoperative PTA‐ABGs were 26.5 ± 12.6 dB and 14.6 ± 8.8 dB, respectively (P < .05). Recurrence was seen in 8 cases (3.6%), conductive HL requiring revision in 4 (1.8%), perforation in 3 (1.4%), and postand intraoperative tube insertion in 11 (5.0%) and 18 ears (8.2%), respectively. In 215 cases of high‐risk perforation, the average pre‐ and postoperative PTA‐ABGs were 21.7 ± 13.5 dB and 11.9 ± 9.3 dB, respectively (P < .05). Complications included recurrent perforation in 9 ears (4.2%), conductive HL requiring revision in 4 (1.9%), postoperative and intraoperative tube insertion in 4 (1.9%) and 6 ears (2.8%), respectively. In 98 cases of atelectasis, the average pre‐ and postoperative PTA‐ABGs were 20.2 ± 10.9 dB and 14.2 ± 10.2 dB, respectively (P < .05). Complications included 1 perforation (1.0%), conductive loss requiring revision in 2 cases (2.0%), and post‐ and intraoperative tube insertion in 7 (7.1%) and 12 ears (12%), respectively. In 103 cases to improve hearing (audiologic), the average pre‐ and postoperative PTA‐ABGs were 33.6 ± 9.6 dB and 14.6 ± 10.1 dB, respectively (P < .05). Complications included 1 perforation (1.0%), conductive loss requiring revision in 11 (11%), and post‐ and intraoperative tube insertion in 6 (5.8%) and 2 (1.9%), respectively. Conclusions: Cartilage tympanoplasty achieves good anatomical and audiologic results when pathology and status of the ossicular chain dictate the technique utilized. Significant hearing improvement was realized in each pathological group. In the atelectatic ear, cartilage allowed us to reconstruct the TM with good anatomic results compared to traditional reconstructions, which have shown high rates of retraction and failure. In cholesteatoma, cartilage tympanoplasty using the palisade technique resulted in precise reconstruction of the TM and helped reduce recurrence. In cases of high‐risk perforation, reconstruction with cartilage yielded anatomical and functional results that compared favorably to primary tympanoplasty using traditional techniques. We believe the indications for cartilage tympanoplasty (atelectatic ear, cholesteatoma, high‐risk perforation) were validated by these results.


Laryngoscope | 1997

Hearing Results With Cartilage Tympanoplasty

John L. Dornhoffer

Cartilage has shown promise as a graft material to close perforations in the tympanic membrane (TM), particularly in cases of advanced middle ear pathology. Although it is similar to fascia, its more rigid quality tends to resist resorption and retraction. However, it is this rigid quality that has led many to anticipate a significant conductive hearing loss when using cartilage to reconstruct the TM. Because little has been reported in the literature comparing hearing results using cartilage with results using other grafting materials, this retrospective study was conducted to compare the hearing results of patients with cartilage tympanoplasty with results in patients who underwent revision tympanoplasty using perichondrium. Both series of patients had undergone type I tympanoplasty, and the middle ear pathology was considered to be similar between the two groups. TM closure was achieved in all 22 patients undergoing cartilage reconstruction, but three of the 20 patients undergoing perichondrium reconstruction had a recurrent perforation during the follow‐up period (approximately 1 year). The average pre‐ and postoperative puretone average air‐bone gap (PTA‐ABG) was 21.1 dB and 6.8 dB for the cartilage group and 17.9 dB and 7.7 dB for the perichondrium group, respectively. These gains in hearing were statistically significant (P < 0.001 in each case), but there was no statistically significant difference in hearing results between the two groups. Analysis of the PTA‐ABG as a function of percentage of TM reconstructed showed no statistically significant difference in hearing results due to percentage of cartilage used. These results indicate that cartilage tympanoplasty offers the possibility of a rigorous TM reconstruction with excellent postoperative hearing results.


Otology & Neurotology | 2001

Prognostic factors in ossiculoplasty: a statistical staging system.

John L. Dornhoffer; Edward K. Gardner

Objective To determine factors that predict hearing results using a standard prosthesis system. Study Design Retrospective chart review. Setting Tertiary referral center. Patients All patients undergoing ossiculoplasty with the Dornhoffer HAPEX partial and total ossicular replacement prostheses (PORP and TORP) from February 1995 to May 1999 who had documented postoperative follow-up and no congenital atresia or stapes fixation. A total of 185 patients (200 ears), 105 men and 80 women, were evaluated. Interventions Ossiculoplasty with the Dornhoffer prostheses. Main Outcome Measures Hearing results using a four-frequency pure-tone average air–bone gap (PTA-ABG). Multivariate statistical analysis determined the effect of mucosal status, ossicular chain status, and type of reconstruction techniques on hearing. Results The PTA-ABGs were 13.4 ± 8.1 dB and 14.0 ± 8.4 dB for the PORPs (n = 114) and TORPs (n = 86), respectively, which was not statistically different. When the malleus handle was present (n = 126), the PTA-ABG was 11.6 ± 6.2 dB, compared with 16.9 ± 10.1 dB when it was absent (n = 74), which was statistically significant (p < 0.05). Mucosal fibrosis, drainage, revision ear surgery, and type of surgical procedure had a significant detrimental impact on hearing. The type of pathologic process (perforation vs. cholesteatoma) had no significant impact on hearing results. Conclusions The revised staging system, the Ossiculoplasty Outcome Parameter Staging Index, more adequately predicts hearing outcome in this series of 200 cases.


Laryngoscope | 2007

Repetitive Transcranial Magnetic Stimulation for Tinnitus: A Case Study

Jason Smith; Mark Mennemeier; Twyla Bartel; Kenneth C. Chelette; Timothy Kimbrell; William J. Triggs; John L. Dornhoffer

Objectives/Hypothesis: Correlate subjective improvements in tinnitus severity with restoration of cortical symmetry and sustained attention after neuronavigated low‐frequency, repetitive transcranial magnetic stimulation (rTMS).


Journal of Psychosomatic Research | 2012

Methodological aspects of clinical trials in tinnitus: A proposal for an international standard

Michael Landgrebe; Andréia Aparecida de Azevedo; David M. Baguley; Carol A. Bauer; Anthony T. Cacace; Claudia Coelho; John L. Dornhoffer; Ricardo Rodrigues Figueiredo; Herta Flor; Goeran Hajak; Paul Van de Heyning; Wolfgang Hiller; Eman M. Khedr; Tobias Kleinjung; Michael Koller; Jose Miguel Lainez; Alain Londero; William Hal Martin; Mark Mennemeier; Jay F. Piccirillo; Dirk De Ridder; Rainer Rupprecht; Grant D. Searchfield; Sven Vanneste; Florian Zeman; Berthold Langguth

Chronic tinnitus is a common condition with a high burden of disease. While many different treatments are used in clinical practice, the evidence for the efficacy of these treatments is low and the variance of treatment response between individuals is high. This is most likely due to the great heterogeneity of tinnitus with respect to clinical features as well as underlying pathophysiological mechanisms. There is a clear need to find effective treatment options in tinnitus, however, clinical trials differ substantially with respect to methodological quality and design. Consequently, the conclusions that can be derived from these studies are limited and jeopardize comparison between studies. Here, we discuss our view of the most important aspects of trial design in clinical studies in tinnitus and make suggestions for an international methodological standard in tinnitus trials. We hope that the proposed methodological standard will stimulate scientific discussion and will help to improve the quality of trials in tinnitus.


Laryngoscope | 1998

Hearing Results With the Dornhoffer Ossicular Replacement Prostheses

John L. Dornhoffer

The “ideal” prosthesis for ossicular reconstruction should, from a surgical standpoint, require easy manipulation, reduce surgeries to partial or total variants, and be constructed of stable, biocompatible material. From an acoustic standpoint, a prosthesis should weigh 10 to 40 mg, provide proper tension between the tympanic membrane (TM) and stapes, form less than a 30‐degree angle with the TM, and accommodate the malleus. Work was conducted with Smith & Nephew Richards, Inc. (Memphis, TN), to develop a partial ossicular replacement prosthesis (PORP) and a total ossicular replacement prosthesis (TORP) that combined the majority of these features. This retrospective study used a computerized otologic database to identify patients implanted with a Dornhoffer HAPEX PORP or TORP from June 1995 to March 1997. The surgical procedures utilizing these prostheses were primary cholesteatoma and revision surgery of previously performed modified or radical mastoidectomies complicated by poor hearing or chronically draining cavities. Preoperative and postoperative air and bone conduction four‐frequency (500, 1000, 2000, and 3000 Hz) puretone averages (PTAs) were used to calculate the PTA air‐bone gaps (ABGs). Results in 52 cases (follow‐up, 1 year) showed a statistically significant improvement in hearing (P < 0.05) for each group. Excellent hearing results (≤10 dB PTA‐ABG) were seen in 69% of PORP cases and in 35% of TORP cases, and good results (11 to 20 dB PTA‐ABG) were seen in 31% and 50% of PORP and TORP cases, respectively. Designing an ossicular replacement prosthesis with both surgical and acoustic factors in mind has led to encouraging short‐term hearing results.


Brain Stimulation | 2008

Controversy: Does repetitive transcranial magnetic stimulation/ transcranial direct current stimulation show efficacy in treating tinnitus patients?

Berthold Langguth; Dirk De Ridder; John L. Dornhoffer; Peter Eichhammer; Robert L. Folmer; Elmar Frank; Felipe Fregni; Christian Gerloff; Eman M. Khedr; Tobias Kleinjung; Michael Landgrebe; Scott L. Lee; Jean Pascal Lefaucheur; Alain Londero; Renata Marcondes; Aage R. Møller; Alvaro Pascual-Leone; Christian Plewnia; Simone Rossi; Tanit Ganz Sanchez; Philipp Sand; Winfried Schlee; Thomas Steffens; Paul Van de Heyning; Goeran Hajak

BACKGROUND Tinnitus affects 10% of the population, its pathophysiology remains incompletely understood, and treatment is elusive. Functional imaging has demonstrated a relationship between the intensity of tinnitus and the degree of reorganization in the auditory cortex. Experimental studies have further shown that tinnitus is associated with synchronized hyperactivity in the auditory cortex. Therefore, targeted modulation of auditory cortex has been proposed as a new therapeutic approach for chronic tinnitus. METHODS Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are noninvasive methods that can modulate cortical activity. These techniques have been applied in different ways in patients with chronic tinnitus. Single sessions of high-frequency rTMS over the temporal cortex have been successful in reducing the intensity of tinnitus during the time of stimulation and could be predictive for treatment outcome of chronic epidural stimulation using implanted electrodes. RESULTS Another approach that uses rTMS as a treatment for tinnitus is application of low-frequency rTMS in repeated sessions, to induce a lasting change of neuronal activity in the auditory cortex beyond the duration of stimulation. Beneficial effects of this treatment have been consistently demonstrated in several small controlled studies. However, results are characterized by high interindividual variability and only a moderate decrease of the tinnitus. The role of patient-related (for example, hearing loss, tinnitus duration, age) and stimulation-related (for example, stimulation site, stimulation protocols) factors still remains to be elucidated. CONCLUSIONS Even in this early stage of investigation, there is a convincing body of evidence that rTMS represents a promising tool for pathophysiological assessment and therapeutic management of tinnitus. Further development of this technique will depend on a more detailed understanding of the neurobiological effects mediating the benefit of TMS on tinnitus perception. Moreover clinical studies with larger sample sizes and longer follow-up periods are needed.


Laryngoscope | 1995

Hearing preservation in acoustic tumor surgery: results and prognostic factors.

John L. Dornhoffer; Jan Helms; Dirk Hoehmann

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.


Childs Nervous System | 1999

Application of skull base techniques to pediatric neurosurgery

Charles Teo; John L. Dornhoffer; Ehab Y. Hanna; Charles M. Bower

Abstract Techniques for skull base surgery have become well established over the last 10 years. Most of these techniques are used in adult patients for skull base tumors and neurovascular diseases. There are very few large series of pediatric patients in whom skull base approaches have been used, because of the rarity of these conditions. The authors would like to present a relatively large series of 26 pediatric patients who underwent skull base approaches for tumor resection. These tumors involved the anterior cranial base in 5 patients, the medial cranial skull base in 4 patients, and the posterior cranial base in 12 cases. Five patients had tumors that involved two or more fossae. The overall complication rate was 57%, which included temporary cranial nerve palsies, CSF leak and infection. Patients with permanent complications were 8 in number (37%). There was 1 postoperative death from pneumonia approximately 6 weeks after surgery. Complete tumor removal was achieved in 24 of the 26 patients. Skull base tumors in children are often extensive and present significant surgical challenges. Although complete tumor extirpation is the goal in most pediatric patients, this is often achieved only with some morbidity. This paper demonstrates the effectiveness of skull base approaches for these tumors and underscores the high stakes involved.


Otolaryngology-Head and Neck Surgery | 1995

Management of the Open Labyrinth

John L. Dornhoffer; Christian Milewski

Labyrinthine fistulas occur in approximately 5% of cholesteatoma cases, but the management of this difficult problem remains controversial. This study assessed the preoperative presentation and outcome in 37 patients operated on for cholestatoma complicated by labyrinthine fistula. Therapy involved removing the matrix from each fistula and reconstructing the bony wall of the labyrinth with bone dust, fibrin glue, and perichondrium. Corticosteroids were added to the management protocol in more recent cases. A fistula classification scheme was introduced to standardize the reporting of the extent of labyrinthine involvement and results of treatment. The most common preoperative symptoms, sensorineural hearing loss and vertigo, were notably lacking in more than 30% of patients. The fistula test was positive in only 32% of cases. Corticosteroids were seen to have a beneficial impact on postoperative outcome in those cases involving injury to the membranous labyrinth or removal of perilymph.

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Mark Mennemeier

University of Arkansas for Medical Sciences

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Matthew D. Cox

University of Arkansas for Medical Sciences

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Aaron Trinidade

University of Arkansas for Medical Sciences

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Gresham T. Richter

University of Arkansas for Medical Sciences

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Joshua Cody Page

University of Arkansas for Medical Sciences

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Timothy Kimbrell

University of Arkansas for Medical Sciences

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Edward K. Gardner

University of Arkansas for Medical Sciences

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Ginger Brown

University of Arkansas for Medical Sciences

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