Dariush Vosough - Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Bahonar University of Kerman, Kerman, Iran.
Majid Masoudifard - Department of Clinical Sciences, Faculty of Veterinary Medicine, Tehran University, Tehran, Iran.
Abbas Veshkini - Department of Clinical Sciences, Faculty of Veterinary Medicine, Tehran University, Tehran, Iran.
Ali Reza Vajhi - Department of Clinical Sciences, Faculty of Veterinary Medicine, Tehran University, Tehran, Iran.
Sarang Sorouri - Department of Clinical Sciences, Faculty of Veterinary Medicine, Tehran University, Tehran, Iran.

Objective-  To determine the possibility of three-dimensional ultrasonography (۳DUS) and measurement of optical nerve sheet by this method. Design- Descriptive study. Animals- ۱۰ mixed normal dogs (۵males, ۵ females), age ۱-۱.۵ year, and weighting ۱۵±۵ kg Procedure- ۳D ultrasounds of the eyes were evaluated and the normal optical nerves in ۳DUS images were measured using Volouson ۷۳۰ pro. Results- In the obtained ۳D images vitreous body, anterior chamber, and lens cortex and nucleus showed a distinct anechogenic to hypoechogenic. Details of the eyes compartments were better observed by rotating the images in all possible angles and planes using ۳D facilities. Anterior and posterior lens capsule and the optic disk were hyperechogenic. The mean optical nerve in males was: ۳.۸۵ mm and in females it was ۳.۸۶mm. There weren’t a significant difference between ocular nerve measurements of male and female dogs and left and right eyes. Conclusion and Clinical Relevance- The ۳DUS gives useful images for teaching and diagnostic purpose and Lesions of the caudal portion of the orbit (e.g. optic nerve atrophy) are better visualized by this technique. The results of the eye ۳DU in dogs showed marked advantages in image acquisition for interpretation of all aspects of the ocular structures. Measurement of the optic nerve by ۳D ultrasonography and other methods such as CT scan and direct measurement did not have any significant difference.

Three-Dimensional Ultrasonogeraphy, Dog, Eye, Optical nerve