Threshold shift validity by documenting sensorineural acuity level: a useful tool for masking
DOI:
https://doi.org/10.18203/issn.2454-5929.ijohns20201686Keywords:
Masking dilemma, Sensorineural acuity level test, Occlusion effect, Threshold shiftsAbstract
Background: Masking dilemma is a condition prevalent whenever there is significant hearing loss in non-test ear and conductive hearing loss in test ear resulting into narrow or non-existent plateau width. Three feasible ways are divulged to circumvent this condition namely, Sensorineural acuity level testing, Fusion Inferred at threshold and use of insert type transducers. Different circumstances encountered when using insert type transducers and Fusion Inferred at threshold test has made it peril to use. Thus, administration of sensorineural acuity level test has been preferred. Sensorineural acuity level test involves computation of individual threshold shifts and its comparison with normal threshold shifts when a maximum level of bone conducted noise is presented at the centre of forehead via bone conduction vibrator. This research study aims to document normal threshold shifts and its validation in individual with bilateral symmetrical sensorineural hearing loss.
Methods: A prospective study was carried out among 50 normal individuals and 50 patients with bilateral symmetrical sensorineural hearing loss. Pertinent measures were taken to ensure fulfilment of all-inclusive and exclusive criteria. In addition, air conduction and bone conduction threshold were computed using conventional methods followed by administration of sensorineural acuity level test. Necessary comparison was made among the threshold shifts.
Results: Inferences drawn showed closer correlation between sensorineural acuity level threshold and bone conduction thresholds during puretone audiometry.
Conclusions: Sensorineural acuity level test has shown to be effectual in both rehabilitation and medical interventions. Besides, imperative role of an audiologist can be recognized in its administration and elucidation for better prognostication.
References
Jack K, Marshall C, Kristina E, Linda JH, Kim LT. Clinical Masking. Jack K. Handbook of Clinical Audiology, 7th Edition, Kanas, Wolters Kluwer Health, New York; 2015;77-111.
Chaplin, Robert GMA, Richard TMD. The Masking Dilemma and its Solution: Fusion at the Inferred Threshold (FIT) and Sensorineural acuity level (SAL) Tests. American J of Otology. 1983:5(1):34-39.
Hall JW, Sanders JW. Clinical masking. In Musiek FE, Rintelmann WF, eds., Contemporary Perspectives in Hearing Assessment. Boston: Allyn and Bacon. 1999:84-86.
Hall JW, Mueller HG. Audiologists' Desk Reference. Diagnostic Audiology Procedures, Procedures, and Practices. San Diego: Singular Publishing Group; 1997:1.
Frederick NM, John GC. Masking Jeffery WJ. Introduction to Audiology, 11th Edition, Pearson Education, Inc., Upper Saddle River, New Jersey; 2012:130-152.
Hall, James W. The Clinical Challenges of Bone-Conduction measurement. The Hearing J. 2005:58(3):10-15.
Eckley, Jennifer. Normative data for the sensorineural acuity level (SAL) test using conventional earphones and insert earphones at frequencies 500, 1000, 2000 and 4000 Hz using narrowband noise. California State University, Long Beach. 2006:1437901.
Jerger, Tillman, Evanston, III. A New Method for the Clinical Deterination of Sensorineural Acuity Level (SAL). Archives of Otolaryngology. 1960;71(6):948-55.
Shekhar BR, Chandrashekhar SS, Ramanjaneyulu, Hazarika P. Sensori-Neural acuity level test in conductive and mixed hearing loss. Indian J of Otolaryngology. 1987:39(3):114-6.
Robert S, Schlauch, Peggy N. Pure tone Evaluation. Jack K. Handbook of Clinical Audiology, 7th Edition, Kanas, Wolters Kluwer Health, New York; 2015;29-48.
Christina P. Pure-tone audiometry and masking. International J of Audiology. 2011;50:138.
Stanley AG. Conductive Mechanism. Stanley AG. Hearing an Introduction to Psychological and Physiological Acoustics, 5th Edition. Informa Healthcare, UK; 2010:51-70.
Maurice HM. How to eliminate air-bone gaps audiometrically: Use too much masking. ENT J. 2008;87(5):273-6.
Dhondt C, Wouters J, Verhaert N. The SAL test for the characterization of mixed hearing loss in Direct Acoustic Cochlear Implants. In Annual Congress of the Royal Belgian Society of Oto-Rhino-Laryngology, Head and Neck Surgery, Location: Leuven, Belgium; 2016.
John GC, Matthew B, Brian RE, Peter MS, Lianna S, Suzanne DC. Use of noise cancellation earphones in out of booth audiometric evaluations. Inte J of Audiology. 2017;56(12):989-96.
Michael AS, Anna MP, Patrick A, Brian CJM. A Technique for Estimating the Occlusion Effect for Frequencies Below 125 Hz. Europe PubMed Central. 2014;35(1):49-55.
