Biomedical subjects

A G Shoup

Publications and source records attributed to A G Shoup.

5 recordsLinked to original sources

PubMed2001

Inhalant allergy and Meniere's disease: Use of electrocochleography and intranasal allergen challenge as investigational tools.

INTRODUCTION: In an earlier study, we demonstrated the feasibility of using electrocochleography (ECoG) to document changes in inner ear function objectively after intranasal challenge of patients with inhalant allergy (with no prior immunotherapy) and Meniere's disease, using the antigen to which they were most sensitive. OBJECTIVE: We expand on this earlier study and continue to investigate the feasibility of this model in a subset of patients with inhalant allergy and Meniere's disease after immunotherapy. STUDY DESIGN: Prospective study of 11 patients identified with both Meniere's disease and inhalant allergy in the practices of 2 neurotologists at our institution. Patients underwent a baseline ECoG, followed by intranasal challenge with the allergen to which they were most sensitive. This was followed by a second ECoG. RESULTS: Six of 11 patients had at least 1 year of immunotherapy (group 1), and 5 of 11 had had 0 to 6 months of immunotherapy (group 2). Four of 6 group 1 patients had a >15% increase in SP/AP ratio after immunotherapy. In group 2, 2 patients increased the SP/AP in at least 1 ear. No patient with a normal ECoG experienced vestibular symptoms after allergen challenge, whereas 2 of group 1 and 2 of group 2 had vestibular symptoms with abnormal ECoGs. CONCLUSION: This protocol is a useful tool for investigating the relationship of inhalant allergy and Meniere's disease, but needs a larger group of patients and further study to draw valid statistical conclusions.

Allergens↗

PubMed2001

Verification of improved patient outcomes with a partially implantable hearing aid, The SOUNDTEC direct hearing system.

INTRODUCTION: Partially implantable hearing devices have been developed to address some of the user-perceived shortcomings of standard amplification systems. Partially implantable devices are purported to provide improved sound quality as a result of decreased occlusion, decreased feedback, and enhanced clarity resulting from increased high-frequency gain. Such improvements may result in greater user satisfaction. To justify selection of a partially implantable device and undergoing a minor surgical procedure, verification techniques must be used to document user improvement or increased satisfaction over conventional amplification. OBJECTIVE: To evaluate patient satisfaction with the SOUNDTEC direct hearing system. STUDY DESIGN: Within-subjects repeated measures design. METHODS: Objective and subjective evaluation pre- and post-implantation with the SOUNDTEC device. Verification techniques included tonal functional gain measures with traditional amplification and the SOUNDTEC device, word recognition in quiet (NU-6) and in noise (SPIN), the Abbreviated Profile of Hearing Aid Benefit (APHAB), and the Hough Ear Institute Profile (HEIP). RESULTS: Although there was no significant difference between optimal traditional amplification and the SOUNDTEC device for speech perception measures, the SOUNDTEC device yielded statistically significant increased high-frequency functional gain. Subjective reports indicated that the SOUNDTEC device provides a cleaner, more natural sound without feedback than traditional amplification. CONCLUSIONS: Partially implantable hearing aids may address some of the limitations of traditional amplification systems.

Adult↗

PubMed2000

Vestibular dysfunction in Gulf War syndrome.

METHODS: Vestibular complaints of Gulf War veterans were characterized by a nested case-control study of 23 veterans with 3 different Gulf War syndromes and 20 matched control subjects. All subjects completed a standardized symptom questionnaire and underwent standard audiovestibular tests administered by audiologists blinded to group identities. RESULTS: The prevalence of reported dizzy spells was higher in veterans with Gulf War syndromes 1 (100%), 2 (85%), and 3 (100%) than in controls (25%, P < 0.0001). Dizzy spells were more frequent, lasted longer, and involved a wider variety of accompanying symptoms in veterans with syndrome 2 than in those with syndromes 1 and 3. Audiovestibular testing showed greater interocular asymmetry of nystagmic velocity on sinusoidal harmonic acceleration in syndromes 1 (P = 0.015) and 2 (P = 0.002), greater asymmetry of saccadic velocity in syndrome 2 (P = 0.4), diminished nystagmic velocity after caloric stimulation bilaterally in syndrome 3 (P = 0.02 to 0.04), more subjects with pathologic nystagmus (P = 0. 09), and greater interside asymmetry of wave I to III interpeak latency on auditory brain stem response in syndromes 1 (P = 0.005) and 2 (P = 0.07). Asymmetry of gain on sinusoidal harmonic acceleration and pathologic nystagmus were most strongly associated with symptoms of paroxysmal vertigo (P = 0.002 and 0.07, respectively); asymmetry of saccadic velocity, with the severity of vertigo (P = 0.004); and abnormal caloric response, with chronic dysequilibrium (P = 0.006). CONCLUSIONS: The findings are compatible with a subtle neurologic injury from organophosphate-induced delayed neurotoxicity.

Adult↗

PubMed1999

Electrocochleographic changes after intranasal allergen challenge: A possible diagnostic tool in patients with Meniere's disease.

Numerous observers have suggested a relationship between allergy and Meniere's disease, but objective proof has heretofore been limited. Using standard criteria, we studied a group of 7 patients with previously diagnosed Meniere's disease in whom significant allergy to 1 or more inhalants had also been diagnosed. Patients underwent a baseline electrocochleographic study followed by intranasal challenge with a carefully quantified amount of the allergen to which they were most sensitive. This was followed by a second electrocochleogram. Four of the 7 patients demonstrated at least a 15% increase in the summating potential/action potential ratio in 1 ear, associated with the production of subjective inner ear symptoms. We present this protocol as a potentially useful tool to further study whether inhalant allergy may be a causative factor in patients with Meniere's disease.

Administration, Intranasal↗

PubMed1999

Salt-load electrocochleography.

OBJECTIVE: To introduce a new protocol for diagnostic electrocochleography using a pretest oral salt load to improve test sensitivity in patients with suspected inner ear fluid imbalance. STUDY DESIGN: A retrospective review of patients who reported vertigo that, by medical history, was suggestive of an inner ear fluid imbalance was preformed. The patients received a complete audiovestibular evaluation that included a baseline electrocochleogram. Despite the incapacitating nature of their vertigo, there were no symptoms or electrophysiologic abnormalities that would isolate an etiologic ear. After the baseline studies, the patients received 4 g of sodium chloride daily for 3 days before repeat electrocochleography. A control group of 13 healthy volunteers with normal baseline electrocochleography and pure tone audiometry was tested under similar conditions. SETTING: This study was conducted at an ambulatory care clinic associated with a tertiary referral medical center. INTERVENTION: Electrocochleography was performed using alternating polarity clicks presented at a rate of 9.7/sec at 95 dB nHL by an extratympanic TIPtrode electrode and recorded with a Nicolet Spirit (Nicolet Instrument Corp., Madison, WI, U.S.A.). Responses were averaged for 1000 sweeps using a 10-msec time base with bandpass filtering from 5 to 1500 Hz. A summating potential/action potential (SP/AP) ratio of 0.37 was considered the upper limit of normal. MAIN OUTCOME MEASURES: Enhancement in the SP/AP ratio from a normal baseline value to > 0.37 after oral salt loading was indicative of a positive test. RESULTS: None of the ears from control subjects had a positive salt load electrocochleogram, and one or both ears in 38% of the patients in the study group with normal baseline SP/AP ratios and symptoms of inner ear fluid imbalance converted to abnormal. The mean SP/AP ratio of the control group for the conditions before and after salt-load was not statistically different (p = 0.48), although the difference in the mean SP/AP ratio in the study group after salt loading was statistically significant (p = 1.329 x 10(-5)). CONCLUSIONS: A group of patients who reported vertigo with no localizing abnormalities had a statistically significant increase in the mean SP/AP ratio after ingestion of a large quantity of sodium chloride. A modest percentage had elevation of the SP/AP ratio above the upper limit of normal for our audiovestibular lab. The localization of a "salt-senstitive" ear could assist the clinician in the management of these difficult problems with long-term medical therapy or surgical treatment when alternative measures fail.

Adolescent↗