# Novel Instrument for Clinical Evaluations of Active Extraocular Muscle Tension
## 4 Conclusions  
We developed a compact measuring instrument to evaluate the active EOM tension utilizing the FDT. This instrument expedites objective and quantitative estimations of active EOM tension. The proposed device employs a medical swab, frictionless bushing, and an LM guide to reduce mechanical losses during the force transfer to the sensor, which can enhance the measurement accuracy, as shown in Table 1.  
The cotton-tipped medical swab transfers the EOM tension connected to the force sensor as a non-invasive medium. The tilting angle of the swab and force of EOM tension were wirelessly transferred to the laptop for recording and real-time displaying of the measured values. The performance of the proposed instrument was investigated in one eye in each of the three test subjects. The measured values of the tension in all rectus muscles were higher than those of previous studies due to the different measurement methodologies. We believe that the proposed ATMD can be applied to obtain normative measurements of active EOM tension. Future work is necessary to confirm the validity, reliability, reproducibility, and generalizability of the ATMD for possible future use in clinical practice. Figure 8: (a) Summary data of the active EOM tensions for the lateral rectus (LR), medial rectus (MR), superior rectus (SR), and inferior rectus (IR). Data are mean and SD values. (b) Representative active EOM tension records for the MR of the right eye. The other rectus muscles presented similar patterns. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app132011431/s1](https://www.mdpi.com/article/10.3390/app132011431/s1)]([https://www.mdpi.com/article/10.3390/app132011431/s1](https://www.mdpi.com/article/10.3390/app132011431/s1)). Conceptualization, H.J.S. ; methodology, H.K. ; software, H.K. ; validation, H.J.S. ; formal analysis, H.K. and A.G.L. ; investigation, S.K. ; data curation, H.J.S. ; writing--original draft preparation, H.K. ; writing--review and editing, A.G.L. and H.J.S. ; visualization, S.K. ; supervision, A.G.L. ; project administration, H.J.S. ; funding acquisition, H.J.S. All authors have read and agreed to the published version of the manuscript. This work was supported by Konkuk University Medical Center Research Grant 2023 (K230102). This sponsor had no role in the design or conduct of this research. The study was conducted in accordance with the Declaration of Helsinki and approved by the Institutional Review Board of Konkuk University Medical Center (registration number: 2023-03-050-001). Informed Consent Statement: Informed consent was obtained from all subjects involved in the study. All relevant data are within the manuscript. The authors declare no conflict of interest. +++ ==WARNING: Truncated because of repetitions==  
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