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Veterinary ophthalmology2022; 25 Suppl 1(Suppl 1); 17-24; doi: 10.1111/vop.12971

Corneal thickness and anterior chamber depth of the normal adult horse as measured by ultrasound biomicroscopy.

Abstract: To determine corneal thickness (CT) and axial anterior chamber depth (ACD) using ultrasound biomicroscopy (UBM) in normal adult horses. To compare corneal thickness measurements between UBM and ultrasonic pachymetry. Methods: Sixty eyes of 30 healthy adult horses aged 8-24 years. Methods: Ultrasonic pachymetry (velocity of 1640 m/s) was utilized to obtain measurements of the central, superior, temporal, inferior, and nasal cornea. Triplicate images of the same corneal locations were acquired using UBM (50 MHz). Images of the axial anterior chamber were used to measure ACD. Intraocular pressure (IOP) was estimated using rebound tonometry, and axial globe length was measured using ultrasonographic biometry. Results: CT (mean ± SD µm) measured by UBM was 854 ± 61 (central), 994 ± 58 (superior), 930 ± 57 (temporal), 979 ± 55 (inferior), and 898 ± 48 (nasal). CT measured by UBM was greater than that measured by ultrasonic pachymetry at all locations and was statistically significant at all locations except inferior (p = 0.0006-0.048). No sex nor age effect was detected for CT at any location. The repeatability of ultrasonic pachymetry was superior to that of UBM. Mean ± SD ACD was 5.74 ± 0.41 mm. A weak positive correlation was identified between central CT and IOP and between central CT and axial globe length. Conclusions: Normal data for CT and ACD of the adult horse obtained using UBM are provided. CT determined by UBM was greater relative to pachymetry at all corneal locations.
© 2022 American College of Veterinary Ophthalmologists.
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Publication Date: 2022-01-27 PubMed ID: 35084084PubMed Central: PMC9246829DOI: 10.1111/vop.12971Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research article focuses on determining the thickness of the cornea and the depth of anterior chamber of the adult horse’s eye using ultrasound biomicroscopy (UBM). It also compares the measurements taken by UBM with those taken by ultrasonic pachymetry.

Methodology

  • Researchers studied 60 eyes of 30 healthy adult horses aged 8-24 years old.
  • Ultrasonic pachymetry, a method of measuring corneal thickness, was used to collect measurements from central, superior, temporal, inferior, and nasal areas of the cornea.
  • The same corneal locations were observed with UBM for comparison.
  • Images of the axial anterior chamber were used to measure its depth (ACD).
  • Other measurements included intraocular pressure (IOP) estimated using rebound tonometry and axial globe length assessed using ultrasonographic biometry.

Results

  • The corneal thickness (CT) measured using UBM was greater than those measured using ultrasonic pachymetry in all areas,
  • The difference in measurements was found to be statistically significant in all the locations except the inferior part of the cornea.
  • No impact of sex or age on CT was found.
  • The repeatability of pachymetry was found to be superior compared to UBM.
  • The average depth of the anterior chamber was found to be 5.74 mm.
  • A weak positive correlation was identified between central CT and IOP and also between central CT and axial globe length.

Conclusion

  • The study provided normal data for both corneal thickness and anterior chamber depth in adult horses using UBM.
  • CT measured by UBM was found to be greater than that measured by pachymetry at all corneal locations.

Cite This Article

APA
Knickelbein KE, Lassaline ME, Kim S, Scharbrough MS, Thomasy SM. (2022). Corneal thickness and anterior chamber depth of the normal adult horse as measured by ultrasound biomicroscopy. Vet Ophthalmol, 25 Suppl 1(Suppl 1), 17-24. https://doi.org/10.1111/vop.12971

Publication

Veterinary ophthalmology
ISSN: 1463-5224
NlmUniqueID: 100887377
Country: England
Language: English
Volume: 25 Suppl 1
Issue: Suppl 1
Pages: 17-24

Researcher Affiliations

Knickelbein, Kelly E
  • Veterinary Medical Teaching Hospital, University of California-Davis, Davis, California, USA.
Lassaline, Mary E
  • Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
Kim, Soohyun
  • Veterinary Medical Teaching Hospital, University of California-Davis, Davis, California, USA.
Scharbrough, Machal S
  • School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
Thomasy, Sara M
  • Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.
  • Department of Ophthalmology and Vision Science, University of California-Davis, Davis, California, USA.

MeSH Terms

  • Animals
  • Anterior Chamber / diagnostic imaging
  • Biometry
  • Cornea / diagnostic imaging
  • Corneal Pachymetry / veterinary
  • Horses
  • Microscopy, Acoustic / methods
  • Microscopy, Acoustic / veterinary

Grant Funding

  • P30 EY012576 / NEI NIH HHS
  • P30 EY12576 / NIH HHS
  • VAF2019-2 / ACVO Vision for Animals Foundation

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