Arianna Di Stadio1, Massimo Ralli2, Reuven Ishai3, Luca D'Ascanio4, Franco Trabalzini5, Antonio Della Volpe6, Gregorio Babighian1, Giampietro Ricci7. 1. University of Perugia, Permanent Temporal Bone Laboratory, Perugia, Italy. 2. University La Sapienza, Department of Oral and Maxillofacial Sciences, Rome, Italy. 3. Toronto General Hospital, Otolaryngology Department, Toronto, Canada. 4. "Carlo Poma" Civil Hospital, Department of Otolaryngology-Head and Neck Surgery, Mantova, Italy. 5. Meyer Children's Hospital, Otolaryngology unit, Florence, Italy. 6. Santobono-Posillipon Hospital, Otology and Cochlear Implant Unit, Naples, Italy. 7. University of Perugia, Otolaryngology Department, Perugia, Italy.
Abstract
OBJECTIVES: Spiral ganglion (SG) counting is used in experimental studies conducted on age-, noise-, and drug-induced sensorineural hearing loss, as well as in the assessment of cochlear implant performances. Different methods of counting have been reported, but no definite standardization of such procedure has been published. The aim of our study is to identify the best method to count human spiral ganglions (SGs). MATERIALS AND METHODS: By identification of nuclei or nucleoli as described by Schucknect, seven researchers with different experience levels counted SGs in 123 human temporal bones (TBs). Data on time of post-mortem bone removal post-mortem, methods of specimen's fixation, decalcification, and coloration were collected to test their possible influence on human tissue. Percentage, two-tailed t-test, Spearman's test, and one-way ANOVA were used to analyze the data. RESULTS: Nucleoli were identified in 61% of cases, whereas nuclei were recognized in 100% of cases (p<0.005). Nucleoli presence in all four segments in the same temporal bone (TB) was observed in 69 cases (92%), whereas nuclei were identified in all four segments in 103 cases (83.7%) (p<0.001). The junior investigators requested a double check by the seniors in 25 (20.3%) cases for identifying and counting nucleoli, whereas the senior researchers showed no doubts in their identification and count. The only parameter positively affecting nucleoli identification in tissue preparation was bone removal for <12 h with respect to longer post-mortem time (p<0.001). CONCLUSION: We suggest counting nuclei, rather than nucleoli, for spiral ganglion computation because of easier recognition of nuclei, especially in case of investigator's limited experience.
OBJECTIVES: Spiral ganglion (SG) counting is used in experimental studies conducted on age-, noise-, and drug-induced sensorineural hearing loss, as well as in the assessment of cochlear implant performances. Different methods of counting have been reported, but no definite standardization of such procedure has been published. The aim of our study is to identify the best method to count human spiral ganglions (SGs). MATERIALS AND METHODS: By identification of nuclei or nucleoli as described by Schucknect, seven researchers with different experience levels counted SGs in 123 human temporal bones (TBs). Data on time of post-mortem bone removal post-mortem, methods of specimen's fixation, decalcification, and coloration were collected to test their possible influence on human tissue. Percentage, two-tailed t-test, Spearman's test, and one-way ANOVA were used to analyze the data. RESULTS: Nucleoli were identified in 61% of cases, whereas nuclei were recognized in 100% of cases (p<0.005). Nucleoli presence in all four segments in the same temporal bone (TB) was observed in 69 cases (92%), whereas nuclei were identified in all four segments in 103 cases (83.7%) (p<0.001). The junior investigators requested a double check by the seniors in 25 (20.3%) cases for identifying and counting nucleoli, whereas the senior researchers showed no doubts in their identification and count. The only parameter positively affecting nucleoli identification in tissue preparation was bone removal for <12 h with respect to longer post-mortem time (p<0.001). CONCLUSION: We suggest counting nuclei, rather than nucleoli, for spiral ganglion computation because of easier recognition of nuclei, especially in case of investigator's limited experience.
Authors: Arianna Di Stadio; Antonio Della Volpe; Massimo Ralli; Fiammetta Korsch; Antonio Greco; Giampietro Ricci Journal: J Int Adv Otol Date: 2020-12 Impact factor: 1.017
Authors: Arianna Di Stadio; Laura Dipietro; Antonietta De Lucia; Franco Trabalzini; Giampietro Ricci; Francesco Martines; Vincenzo Pastore; Antonio della Volpe Journal: J Int Adv Otol Date: 2019-08 Impact factor: 1.017