Breit S, Künzel W, Oppel M
Institute of Anatomy, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria.
Anat Histol Embryol. 2003 Aug;32(4):224-7. doi: 10.1046/j.1439-0264.2003.00464.x.
Casts of the nasolacrimal duct system were obtained from 50 euthanised cats including brachy-, meso- and dolichocephalic breeds. The course of the nasolacrimal duct, which was assessed radiographically and gross-anatomically, was strongly related to the shape of the skull. In meso- and dolichocephalic cats the nasolacrimal duct formed a dorsally opened arch with the descending part being directed rostroventrally. The main part of the duct passed the nasal cavity in a rather horizontal course parallel to the hard palate and was located ventrally to the lacrimal foramen. However, foreshortening of the face was associated with a right-angled or even acute-angled alignment of the duct. In higher degrees of brachycephaly the main part of the duct ascended beyond the level of the lacrimal foramen and passed the nasal cavity dorsal to the level of the lacrimal foramen. This specific course of the nasolacrimal duct in brachycephalic cats was consistent with a steeper alignment and attachment of the maxilloturbinate. Accessory orifices of the nasolacrimal duct opening into the nasal cavity had never been observed. The present results strongly suggest that the specific course of the nasolacrimal duct in brachycephalic cats might hinder the drainage of the lacrimal fluid irrespective of the diameter of the lumen of the nasolacrimal duct system.
从50只安乐死的猫身上获取鼻泪管系统铸型，这些猫包括短头型、中头型和长头型品种。通过影像学和大体解剖学评估鼻泪管的走行，发现其与头骨形状密切相关。在中头型和长头型猫中，鼻泪管形成一个背侧开口的弓形，下降部分向前腹侧走行。鼻泪管的主要部分在与硬腭平行的相当水平的走行中穿过鼻腔，并位于泪孔的腹侧。然而，面部缩短与鼻泪管呈直角甚至锐角排列有关。在更高程度的短头畸形中，鼻泪管的主要部分上升超过泪孔水平，并在泪孔水平的背侧穿过鼻腔。短头型猫鼻泪管的这种特定走行与上颌鼻甲更陡峭的排列和附着一致。从未观察到鼻泪管通向鼻腔的副孔。目前的结果强烈表明，短头型猫鼻泪管的特定走行可能会阻碍泪液引流，而与鼻泪管系统管腔的直径无关。
