PMID- 38161797
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20240103
IS  - 1662-4548 (Print)
IS  - 1662-453X (Electronic)
IS  - 1662-453X (Linking)
VI  - 17
DP  - 2023
TI  - Optimization of pharmacological interventions in the guinea pig animal model-a 
      new approach to calculate the perilymph volume of the scala tympani.
PG  - 1297046
LID - 10.3389/fnins.2023.1297046 [doi]
LID - 1297046
AB  - OBJECTIVE: The guinea pig serves as a well-established animal model for inner ear 
      research, offering valuable insights into the anatomy, physiology, and 
      therapeutic interventions of the auditory system. However, the heterogeneity of 
      results observed in both in-vivo experiments and clinical studies poses 
      challenges in understanding and optimizing pharmacotherapy outcomes. This 
      heterogeneity may be due to individual differences in the size of the guinea pig 
      cochlea and thus in the volume of the scala tympani (ST), which can lead to 
      different drug concentrations in the ST, a fact that has been largely overlooked 
      thus far. To address this issue, we aimed to develop an approach for calculating 
      the individual volume of perilymph within the ST before and after cochlear 
      implant insertion. METHOD: In this study, high-resolution muCT images of a total 
      of n = 42 guinea pig temporal bones were used to determine the volume of the ST. 
      We compared fresh, frozen, and fixed tissues from both colored and albino strains 
      to evaluate the potential influence of tissue condition and strain on the 
      results. RESULTS: Our findings demonstrate a variability in mean ST volume with a 
      relative standard deviation (RSD) of 14.7%, comparable to studies conducted with 
      humans (range RSD: 5 to 20%). This indicates that the guinea pig cochlea exhibits 
      similar variability to that of the human cochlea. Consequently, it is crucial to 
      consider this variability when designing and conducting studies utilizing the 
      guinea pig as an animal model. Furthermore, we successfully developed a tool 
      capable of estimating ST volume without the need for manual segmentation, 
      employing two geometric parameters, basal diameter (A) and width (B) of the 
      cochlea, corresponding to the cochlear footprint. The tool is available for free 
      download and use on our website. CONCLUSION: This novel approach provides 
      researchers with a valuable tool to calculate individual ST volume in guinea 
      pigs, enabling more precise dosing strategies and optimization of drug 
      concentrations for pharmacotherapy studies. Moreover, our study underscores the 
      importance of acknowledging and accounting for inter-individual variability in 
      animal models to enhance the translational relevance and applicability of 
      research outcomes in the field of inner ear investigations.
CI  - Copyright (c) 2023 Grzybowski, Malfeld, Lenarz, Scheper and Schurzig.
FAU - Grzybowski, Marleen
AU  - Grzybowski M
AD  - Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical 
      School, Hannover, Germany.
AD  - German Hearing Center Hannover, Hannover Medical School, Hannover, Germany.
FAU - Malfeld, Kathrin
AU  - Malfeld K
AD  - Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical 
      School, Hannover, Germany.
AD  - Center for Biomedical Engineering, Implant Research and Development (NIFE), 
      Hannover Medical School, Hannover, Germany.
FAU - Lenarz, Thomas
AU  - Lenarz T
AD  - Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical 
      School, Hannover, Germany.
AD  - German Hearing Center Hannover, Hannover Medical School, Hannover, Germany.
AD  - Center for Biomedical Engineering, Implant Research and Development (NIFE), 
      Hannover Medical School, Hannover, Germany.
FAU - Scheper, Verena
AU  - Scheper V
AD  - Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical 
      School, Hannover, Germany.
AD  - Center for Biomedical Engineering, Implant Research and Development (NIFE), 
      Hannover Medical School, Hannover, Germany.
FAU - Schurzig, Daniel
AU  - Schurzig D
AD  - Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical 
      School, Hannover, Germany.
AD  - MED-EL Research Center, Hannover, Germany.
LA  - eng
PT  - Journal Article
DEP - 20231215
PL  - Switzerland
TA  - Front Neurosci
JT  - Frontiers in neuroscience
JID - 101478481
PMC - PMC10754993
OTO - NOTNLM
OT  - cochlear implantation
OT  - cochlear modeling
OT  - drug delivery
OT  - electrode coating
OT  - individualized implantation
OT  - pharmacokinetics
COIS- The CI electrodes employed for the present investigations were supplied by 
      MED-EL. The authors declare that the research was conducted in the absence of any 
      commercial or financial relationships that could be construed as a potential 
      conflict of interest.
EDAT- 2024/01/02 11:43
MHDA- 2024/01/02 11:44
PMCR- 2023/01/01
CRDT- 2024/01/01 04:10
PHST- 2023/09/19 00:00 [received]
PHST- 2023/11/29 00:00 [accepted]
PHST- 2024/01/02 11:44 [medline]
PHST- 2024/01/02 11:43 [pubmed]
PHST- 2024/01/01 04:10 [entrez]
PHST- 2023/01/01 00:00 [pmc-release]
AID - 10.3389/fnins.2023.1297046 [doi]
PST - epublish
SO  - Front Neurosci. 2023 Dec 15;17:1297046. doi: 10.3389/fnins.2023.1297046. 
      eCollection 2023.