Cochlin-tomoprotein (CTP) detection test identifies traumatic perilymphatic fistula due to penetrating middle ear injury

Abstract

Conclusions: The cochlin-tomoprotein (CTP) detection test can be used to make a definite, objective diagnosis of traumatic perilymphatic fistula (PLF), and therefore offers valuable information on patient selection for surgical treatment. Objectives: Penetrating middle ear injury can cause traumatic PLF, which is a surgically treatable otologic emergency. Recently, we have reported on CTP, a novel perilymph-specific protein. The purpose of this study was to determine if the CTP detection test is useful for the diagnosis of traumatic PLF. Methods: This was a prospective study of CTP detection in penetrating middle ear injury cases with tympanic membrane perforation and hearing loss. Results: A total of seven individuals were included in this study. CTP was detected in three of four cases with posterosuperior quadrant perforation of the tympanic membrane. In one of these three cases, even though the high resolution CT scan was not suggestive of PLF and the perilymph leakage could not be visualized intraoperatively, the CTP detection test was able to detect PLF. In two cases, the preoperative positive test results enabled us to make a diagnosis of PLF and a decision for surgical treatment. CTP was not detected in the cases with anterior or inferior tympanic membrane perforation.

Keywords::

• Middle ear trauma
• hearing loss
• COCH gene
• cochlin isoform

Acknowledgments

We thank Dr Shin-Ichi Haginomori, Department of Otorhinolaryngology Osaka Medical College, Dr Hideki Matsuda, Department of Otorhinolaryngology, Yokohama City University School of Medicine, and Dr Hiroshi Ogawa, Department of Otorhinolaryngology, Fukushima Medical University, for their generous cooperation. This study was supported by Health and Labor Sciences Research Grants in Japan (Research on Measures for Intractable Diseases, Researches on Sensory and Communicative Disorders), a grant from the Ministry of Education, Culture, Sports, Science and Technology. Nippon Medical School and Mitsubishi Chemical Corporation have Japanese patent on this test. Nippon Medical School has Chinese, Australian, European, and US patent. None of the authors have received any financial compensation for their work.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.