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Biomedical subjects

A G Schuring

Publications and source records attributed to A G Schuring.

At least 19 recordsLinked to original sources
PubMed2001

Stapedectomy following tympanoplasty.

The aim of this study was to evaluate the success of stapedectomy in patients who have previously had a tympanoplasty because of chronic otitis media (COM). Fourteen patients from a private otology practice had undergone tympanoplasty for COM and subsequently underwent stapedectomy. Measurements were taken of the air-bone gap (ABG) closure and pure tone average (PTA) which showed hearing improvement. Patients had a mean 36.9 dB PTA hearing gain with 79 per cent closing the ABG to within 20 dB. The need for stapedectomy alone is a rare occurrence for patients with a history of COM requiring a tympanoplasty. Hearing improvement following stapedectomy in these cases was significant, although somewhat less than following traditional stapedectomy in otosclerosis alone.

Adult↗
PubMed2000

Cavum major tympano-ossiculoplasty.

OBJECTIVE: To evaluate the success of tympano-ossiculoplasty in patients with previous canal wall down mastoidectomy. STUDY DESIGN: A retrospective review of 79 patients who underwent cavum major tympano-ossiculoplasty from a total of 1,910 tympanomastoidectomies from 1976 to 1998. OUTCOME MEASURES: The results of air-bone gap closure, surgical findings, and revision surgery are presented. RESULTS: In 63% of patients, the air-bone gap closed to within 20 dB with a mean gain of 14.7 dB. CONCLUSION: A significant percentage of patients will gain substantial improvement in their hearing after cavum major tympano-ossiculoplasty with minimal risk.

Adolescent↗
PubMed2000

Ossiculoplasty in canal wall down mastoidectomy.

OBJECTIVE: The aim of this study was to evaluate the initial and longer term success of closing the air-bone gap (ABG) to 20 dB in ossiculoplasty with canal wall down mastoidectomy. METHODS: This study was conducted at a private otologic practice. Patients included those who underwent ossiculoplasty from 1989 to 1996 with canal wall down mastoidectomy, whether primary or revision (33 from a total of 387 tympanomastoidectomies). Outcome measures included ABG closure, long-term hearing stability, mastoid appearance, extrusion, and sensorineural hearing loss. RESULTS: Almost 64% of ABGs were closed to within 20 dB. The mean pure-tone average improvement was 12.3 dB. The mean PTA hearing decline in the years after surgery was slightly less than 1 dB/year. CONCLUSION: Hearing improvement with a stable long-term hearing result is possible with canal wall down mastoidectomy. The potential for hearing gain is greatest for patients having larger preoperative ABGs.

Audiometry, Pure-Tone↗
PubMed1998

Revision stapedectomy for incus erosion: long-term hearing.

One of the most common ossicular problems in revision stapedectomy is the eroded incus. Revision surgery has been reported as successful in 70% to 80% of cases at 1 year. Little is written about long-term results or the association of erosion with various prostheses. We evaluated 83 cases from 1 to 20 years, including multiple revisions. In 23 cases the erosion was seen at initial stapedectomy. Surgery was performed with the patient under local anesthesia, with the use of the Lippy modified prosthesis. Initial success was seen in 72% (41/57), satisfactory results in 90%, no change in 5%, and none worse. At 10 years, success had declined to 50% (7 of 14), with 80% satisfactory. The numbers for multiple revisions were lower. Success in nonrevision cases was 90% (21 of 23), dropping to 86% at 10 years, with satisfactory results in 100%. The type of prosthesis associated with erosion was a crimped wire in 34% (24 of 70), a plastic strut in 23%, and a Robinsion prosthesis in 17%. We conclude that the risk of incus erosion appears less with the Robinson prosthesis. The Lippy modified prosthesis yields good long-term results, particularly when erosion is seen at initial stapedectomy. Results worsen with subsequent revision.

Adolescent↗
PubMed1998

Prosthesis size in stapedectomy.

Primary stapedectomies were performed on 60 patients with bilateral otosclerosis. Every patient had a 4 mm long Robinson prosthesis with a 0.4 mm wide shaft placed in one ear and a 4 mm long Robinson prosthesis with 0.6 mm wide shaft placed in the opposite ear. With the 0.4 mm wide prosthesis, 54 patients overclosed the air bone gap and 6 were within 10 dB of closing. With the 0.6 mm wide prosthesis, which was placed in the opposite ear, 51 patients overclosed their air-bone gap and 8 were within 10 dB of closing. We conclude that there is no statistical difference in hearing results between the 0.4 mm and the 0.6 mm wide Robinson prosthesis when they are used in a partial stapedectomy with a vein graft covering the oval window.

Adolescent↗
PubMed1998

Short- and long-term results of stapedectomy in children.

Studies have indicated that stapedectomy can be an effective procedure in children for correcting conductive hearing losses due to juvenile otosclerosis. However, because childhood otosclerosis is rare and children commonly choose to use hearing aids in lieu of undergoing surgery, little outcome data are available. The purpose of this retrospective study was to provide additional outcome data in both the short and the long term. Stapedectomies were performed on 47 children. Preoperative hearing results were compared with 6-month postoperative hearing results. Hearing results for the children who had long-term follow-up (5 years or more) were compared with the 6-month postoperative results. Stapedectomy was successful (postoperative air conduction pure-tone average [PTA] within 10 dB of the preoperative bone conduction PTA) in 91.7% of the cases. The mean overclosure of the preoperative bone conduction PTA by the postoperative air conduction PTA was 0.2 dB. The mean PTA hearing improvement was 32.8 dB. Results from the 21 children (28 ears) who had long-term follow-up indicated an average 0.7 dB/year PTA worsening from the 6-month postoperative PTA. Results from this study provide additional evidence that stapedectomy can be an effective procedure for correcting conductive hearing losses due to juvenile otosclerosis.

Adolescent↗
PubMed1998

Partial ossicular reconstruction in children: a review of 62 operations.

OBJECTIVE/HYPOTHESIS: The published experience and audiometric results with ossicular reconstruction in children are limited. To better understand the role of ossiculoplasty in children, audiometric results were examined for partial ossicular reconstructions performed on a pediatric population. STUDY DESIGN: Retrospective. METHODS: Sixty-two partial ossicular reconstructions performed on a pediatric population were reviewed for audiometric results, prosthesis extrusion rates, and mechanisms of failure at revision. Comparison of techniques and prosthesis types: porous polyethylene partial ossicular replacement prosthesis (POP), Schuring ossicle cup (SOC), and modified Robinson prosthesis (MRP) were also evaluated. Follow-up ranged from 6 to 72 months. RESULTS: Six-month hearing results showed postoperative airbone gaps less than or equal to 20 dB in 77% of cases. Successful results at 1 and 2 years were retained in 66% and 63% of cases, respectively. Results for POPs at 1 and 2 years were 78% and 89%. Results for SOCs at 1 and 2 years were 61% and 55%. The overall extrusion rate was approximately 3%. CONCLUSIONS: These results compare favorably with those from other, mostly adult, studies. Comparison of prosthesis types revealed generally stable long-term results with few significant differences. Success with ossiculoplasty in children can be obtained by applying the same principles and approach to ossicular reconstruction as used in adults. Ossicular reconstruction in children remains a secondary goal after establishing a safe, dry, and stable ear. A discussion of techniques and comparative literature review are presented.

Adolescent↗
PubMed1998

Clinical utility of the 512-Hz Rinne tuning fork test.

OBJECTIVE: This study aimed to examine the reliability of the 512-Hz Rinne tuning fork test to detect conductive hearing losses. The effects of tester experience, the use of masking, and the interpretation of equivocal (+/-) Rinne results on test reliability also were examined. STUDY DESIGN: Retrospective. SETTING: Private otology practice. PATIENTS: 1,000 adult patients (2,000 ears) seen for their initial otologic evaluation. INTERVENTIONS: Diagnostic. MAIN OUTCOME MEASURE: Sensitivity of the 512-Hz Rinne tuning fork test was assessed by comparing tuning fork results with the pure-tone average air-bone gap. RESULTS: Results showed the 512-Hz Rinne tuning fork test could be very effective at detecting conductive hearing losses when performed by an experienced tester and when masking was used. Sensitivity was lower when masking was not used and lowest when the Rinne was performed by a less-experienced tester. Sensitivity for all groups was improved by interpreting equivocal results as indicating a conductive loss. CONCLUSIONS: Despite reports of poor reliability, the 512-Hz Rinne tuning fork test can be an important tool in an otology practice for the detection of conductive hearing losses and for confirming audiometric findings. In primary care settings, the Rinne would be most effective as part of a screening program for conductive hearing losses, but not as the sole indicator for referral.

Adult↗
PubMed1998

Pediatric tympanoplasty of iatrogenic perforations from ventilation tube therapy.

OBJECTIVES: This study aimed to determine surgical outcome of tympanoplasty in children with iatrogenic perforations, to determine whether age is a factor in successful tympanoplasty, and to determine whether surgical outcome is affected by preoperative factors (e.g., perforation size and location, otorrhea, cholesteatoma, and tympanosclerosis) or surgical technique (e.g., underlay or overlay). STUDY DESIGN: The study design was a retrospective series review. SETTING: The study was conducted at a multiphysician private otologic practice. PATIENTS: Ninety-three pediatric patients with iatrogenic perforations caused by the insertion of ventilation tubes for otitis media with effusion (OME) participated. Surgical selection criteria included a year's observation of the perforation with a 6-month OME-free interval in the involved and contralateral ear. The 46 males and 47 females had a mean age at surgery of 10.8 years (standard deviation = 2.9) ranging from 3-16 years. INTERVENTIONS: All patients underwent underlay or overlay tympanoplasty using temporalis fascia grafts. MAIN OUTCOME MEASURES: Outcome was evaluated in terms of drum healing (healed or perforated), hearing (air-bone gap), and complications. RESULTS: There was a graft take-rate of 94.6% with reperforations occurring in 5.4% with an average follow-up of 16.8 months. Duration of follow-up ranged from 10.8-77.5 months. The air-bone gap was completely closed in 53.8% and was closed to within 10 dB in 80.7% and 20 dB in 94.7%. The incidence of major and minor complications was 16.1%. Surgical outcome was not influenced by age, technique, or any of the preoperative factors. CONCLUSIONS: Tympanoplasty of persistent perforations after ventilation tube therapy for recurrent OME can be performed successfully regardless of age, surgical technique, or other preoperative factors.

Adolescent↗
PubMed1997

Stapedectomy in patients with small air-bone gaps.

Controversy exists concerning stapedectomy for patients with small air-bone gaps. The purpose of this study was to examine the results for patients who had a stapedectomy to correct a small (10 dB or less) air-bone gap. One hundred fifty-four patients with suspected otosclerosis were explored and a stapedectomy was performed in 136 (88.3%) of these cases. The mean pure-tone average (PTA) improved 16.7 dB and overdosed the preoperative bone conduction PTA by 8.1 dB. The majority of the stapedectomy patients (89.7%) had a PTA closure greater than or equal to 0 dB. These results showed that stapedectomy can be an effective procedure for eliminating and overdosing even small air-bone gaps due to otosclerosis.

Audiometry, Pure-Tone↗
PubMed1997

Practical use of total and partial ossicular replacement prostheses in ossiculoplasty.

The use of porous polyethylene total and partial ossicular replacement prostheses (TOPs and POPs) for ossicular reconstruction in middle ear surgery was retrospectively reviewed at the Warren Otologic Group, a tertiary referral center for otologic problems. Extrusion rates, lower than those previously reported, and improvement in hearing results were found in 250 cases. Follow-up ranged from 6 months to 8 years. This paper details the optimal placement and relationships of the prosthesis, the interposed tragal cartilage, and the drum. Modifications to the prosthesis have increased stability and ease of reconstruction. The hearing results of both TOP and POP reconstruction, and comparison with the literature, will be presented. With TOPs, the air-bone gap was closed to within 20 dB in 67% of cases. With POPs, similar results were obtained in 81% of cases.

Adolescent↗
PubMed1996

Acoustic reflexes, auditory brainstem response, and MRI in the evaluation of acoustic neuromas.

Patient records were reviewed to determine whether persons with absent acoustic reflexes have a higher incidence of abnormal auditory brainstem response (ABR) results in the absence of a cerebellopontine angle (CPA) tumor than those with normal acoustic reflexes. Results showed patients with absent reflexes to have borderline or abnormal ABR results in 45.2% of the cases. Patients with normal reflexes had borderline or abnormal ABR results in 14.2% of the cases. Results indicate that magnetic resonance imaging is a more appropriate test for patients with absent reflexes, since ABR was often nondiagnostic for a CPA tumor in this group.

Evoked Potentials, Auditory, Brain Stem↗
PubMed1996

Prosthesis on a mobilized stapes footplate.

Managing a mobilized footplate in stapedectomy surgery can be challenging. Between 1963 and 1992, 145 footplates were inadvertently mobilized during otosclerosis surgery. After a vein graft, a 4.0-mm Robinson prosthesis was placed on all footplates, making no attempt to remove the footplate. There were 73 thin, blue footplates and 72 thick, white footplates. Hearing results in the thin, blue footplate group was 97% successful and 100% satisfactory at 3 years. No footplate refixed. In the thick, white group, hearing was 60% successful and 72% satisfactory at 6 months. Footplate refixation was found at revision in all but one unsuccessful case. After revision, the thick, white group had 79% successful and 89% satisfactory hearing results at 3 years. No patient in either group was worse. We conclude that placing a vein graft and a Robinson prosthesis is a safe and effective technique for a mobilized footplate. If the footplate is thin and blue, there is little or no risk of refixation. If the footplate is thick and white, approximately 30% will require revision.

Follow-Up Studies↗
PubMed1996

Stapedectomy in the elderly.

Clinical records were reviewed to examine the effectiveness of stapedectomy in patients 70 years and older. A total of 154 patients was studied, including 11 with profound hearing loss with long-standing otosclerosis. Ages at the time of surgery ranged from 70 to 92 years (mean, 76.3 years). The mean pure-tone average (500, 1,000, 2,000, and 4,000 Hz) improved 30.6 dB after surgery for the 143 patients in the main otosclerotic group and 26.8 dB for the patients in the profound-hearing-loss group. The rate of successful stapedectomies for the 70(+)-year-old patients (90.9%) and the younger comparison group (90.0%) were similar. These findings extend the documented range of stapedectomy as a safe and effective procedure through the eighth decade of life.

Aged↗
PubMed1994

Ossiculoplasty with semibiologic and composite prostheses.

The Lippy-modified Robinson prosthesis has been used for years in revision stapedectomy and has proved successful in reconstructing the absent lenticular process. When this technique fails, an ossicle cup prosthesis can be used. The ossicle cup and columella have been used for 20 years with continuing success. The advantages of the semibiologic prostheses are as follows: The prosthesis can be sized as each case requires, giving a variable height above the remaining stapes. The prosthesis is designed not to touch the promontory or facial nerve canal. The synthetic portion of the semibiologic prosthesis does not touch the tympanic membrane. An efficient perpendicular action is achieved from the tympanic membrane to the stapes footplate. The prosthesis remains in place during tympanic membrane movement. A stable dynamic joint is provided with the stapes capitulum (ossicle cup). A safe platform is provided that distributes the weight of the assembly prosthesis over the entire stapes footplate (ossicle columella). Although both semibiologic prostheses are used routinely for partial and total ossicular replacement, other troublesome and technically difficult ossicular reconstruction problems can also be solved by the adaptability of the synthetic portion of the prosthesis. Because the synthetic portion of the prosthesis can be modified by notching, shaping, and trimming, the following problems can be overcome: A laterally healed tympanic membrane can be reached by increasing the length of the synthetic shaft. In the absence of the stapes capitulum, the cup is notched in two places (180 degrees apart) to fit the shoulders of the remaining stapes. Remaining crura on the footplate can be bypassed by trimming the synthetic footplate to fit in between the crura. The stapes with a low profile can be utilized by increasing the length of the synthetic shaft. An abnormal stapedial tendon attachment to the stapes capitulum can be overcome with a single notch in the cup. An overhanging facial nerve can usually be bypassed by the narrow design of the ossicle columella. The future of ossiculoplasty will rest more on the solution of ancillary problems than on ossiculoplasty techniques. These troublesome ancillary problems include eustachian tube dysfunction, cholesteatoma control, mucosa regeneration, and fibrosis during the healing process. The self-correcting process of ossiculoplasty is an evolutionary process, and the small surgical steps taken are slowly incorporated into surgical principles. Incorporating a synthetic prosthesis within a natural or synthetic ossicle is a logical and evolutionary step in the science of ossicular reconstruction.

Biocompatible Materials↗
PubMed1994

Far-advanced otosclerosis.

Far-advanced otosclerosis (FAO) is an uncommon diagnosis. Hearing levels in patients with FAO may range from profound loss, by air conduction and fragmentary bone conduction thresholds, to no measurable air or bone conduction thresholds. Thus, FAO may be difficult to distinguish from a sensorineural hearing loss. This report presents the results of surgery in 73 ears with FAO, 77 percent of which had improvement in air conduction thresholds of greater than 20 dB. Discrimination was improved by more than 15 percent in 54 percent of cases, and 75 percent realized improvement in use of a hearing aid. There was no evidence that success was related to preoperative hearing. The surgical results of a subgroup of 14 patients having bilateral FAO were also analyzed. For all 14, similar surgical outcomes were achieved in both the initial and the contralateral ear, with six successes bilaterally and eight failures bilaterally. Although far advanced otosclerosis is uncommon and difficult to diagnose, surgery is worthwhile.

Acoustic Stimulation↗
PubMed1994

Simultaneous presentation of facial nerve neuroma and otosclerosis.

Otosclerosis often occurs as a unilateral mixed or conductive hearing loss. In the absence of retrocochlear findings, otologists usually do not pursue further diagnostic testing. A patient who presented to the Warren Otologic Group with a unilateral mixed hearing loss is discussed. He was followed for 1 year with the intent of scheduling a stapedectomy. Two weeks prior to the surgical date, the patient developed a sudden hearing loss and was admitted to the hospital for treatment. Magnetic resonance imaging demonstrated a tiny, enhancing mass in the lateral internal auditory canal, measuring 7 mm in diameter. At surgery, the tumor was found to originate at the union of the nervus intermedius and the facial nerve. The simultaneous occurrence of facial nerve neuroma and otosclerosis is discussed, with emphasis on a thorough evaluation of all unilateral mixed hearing losses, including those attributable to otosclerosis.

Adult↗