{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T20:29:45Z","timestamp":1783110585031,"version":"3.54.6"},"reference-count":57,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,1,7]],"date-time":"2024-01-07T00:00:00Z","timestamp":1704585600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>This study\u2019s CT scan-based morphometric analysis of 50 adult dogs explored the relationship between skull shape variations (determined by the skull index, SI), optic chiasm, optic canals, and orbital shape. Dogs were classified as brachycephalic (SI \u2265 59), mesocephalic (SI \u2265 51 but &lt;59), and dolichocephalic (SI &lt; 51). No significant age or weight differences were observed. Skull lengths (brachycephalic: 11.39 \u00b1 1.76 cm, mesocephalic: 15.00 \u00b1 2.96 cm, dolichocephalic: 17.96 \u00b1 3.44 cm) and facial lengths (brachycephalic: 3.63 \u00b1 1.00 cm, mesocephalic: 6.46 \u00b1 1.55 cm, dolichocephalic: 8.23 \u00b1 1.03 cm) varied significantly, with shorter orbital depths (brachycephalic: 2.58 \u00b1 0.42 cm, mesocephalic: 3.19 \u00b1 0.65 cm, dolichocephalic: 3.61 \u00b1 0.77 cm) in brachycephalic dogs. The optic chiasm-to-inion horizontal length ratio to cranial horizontal length positively correlated with the SI (r = 0.883, p &lt; 0.001), while the ratio to neurocranial length showed no SI correlation (range: 55.5\u201375.0). Brachycephalic breeds had a significantly wider optic canal angle (93.74 \u00b1 16.00\u00b0), along with broader lacrimal-zygomatic and zygomatic frontal process angles. These findings highlight the zygomatic bone\u2019s role in influencing breed-specific orbital variations by connecting the face to the neurocranium, projecting the orbital rim outward and forward with facial shortening.<\/jats:p>","DOI":"10.3390\/ani14020197","type":"journal-article","created":{"date-parts":[[2024,1,8]],"date-time":"2024-01-08T03:49:04Z","timestamp":1704685744000},"page":"197","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Breed-Specific Skull Morphology Reveals Insights into Canine Optic Chiasm Positioning and Orbital Structure through 3D CT Scan Analysis"],"prefix":"10.3390","volume":"14","author":[{"given":"Yoichiro","family":"Ichikawa","sequence":"first","affiliation":[{"name":"Department of Small Animal Internal Medicine II, School of Veterinary Medicine, Kitasato University, 35-1 Higashi 23 Ban-Cho, Towada 034-8628, Aomori, Japan"},{"name":"Ichikawa Animal Hospital, 118-3 Negiuchi, Matsudo-shi 270-0011, Chiba, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nobuyuki","family":"Kanemaki","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Chuou-ku, Sagamihara 252-5201, Kanagawa, Japan"},{"name":"DVMs Animal Medical Center Yokohama, 2-2 Sawatari, Kanagawa-ku, Yokohama 221-0844, Kanagawa, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3690-2332","authenticated-orcid":false,"given":"Kazutaka","family":"Kanai","sequence":"additional","affiliation":[{"name":"Department of Small Animal Internal Medicine II, School of Veterinary Medicine, Kitasato University, 35-1 Higashi 23 Ban-Cho, Towada 034-8628, Aomori, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,7]]},"reference":[{"key":"ref_1","unstructured":"Hermanson, J.W., DeLahunta, A., Evans, H.E., and Miller, M.E. 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