Diagnosis and Surgical Management of Lens Displacement in the Dog

犬水晶體異位之診斷與外科治療

林中天(Chung-Tien Lin) ； 林郁玟(Yu-Wen Lin)

《中華民國獸醫學會雜誌》 27卷4期 (2001/12) Pp. 245-250

https://doi.org/10.7009/JTCSVS.200112.0245

摘要

水晶體異位是犬常見造成失明的眼睛疾病之一，我們收集及分析50隻至國立台灣大學附設動物醫院就診，並診斷患有水晶體異位的患犬病例之臨床病變及病患資料。我們利用完整的眼科學檢查方法，包括利用眼科裂隙燈臨床顯微鏡、直接及間接檢眼鏡、及電子觸碰式眼壓計等儀器來診斷水晶體異位之類型及其他眼內病變之嚴重性。在50個患犬病例中，無明顯之性別差異，好發年齡為4-6歲及9-11歲兩個年齡區間。特別好發的犬種為混種犬（佔全部病例36%）及瑪爾濟斯犬（佔全部病例24%）。雙側性水晶體異位與單側性水晶體異位之比例約為3:7。總數65隻水晶體異位之患眼中，有28隻為向前方眼前房異位（佔全部病例43%），37隻之為向後方眼後房異位（佔全部病例57%）。在病患患眼之臨床症狀方面，91%已患失明、60%有鞏膜鬱血、26%有眼瞼痙攣、15%有角膜水腫及14%患有結膜充血等現象。在失明的患眼中，大多數（超過50隻患眼）失明的時間已至少長達數週或是數月以上。經詳細眼科學檢查後，發現其他伴隨的眼睛疾病及病變包括青光眼（佔全部患眼之69%）、白內障（佔66%）、葡萄膜炎（佔28%）。只有具完整過往病史的犬才能確定其水晶體異位與其他眼睛疾病之因果關係。在50隻患犬中有42隻接受異位水晶體摘除術（水晶體囊內摘除法），手術可治療及預防水晶體異位後之二次性青光眼及其他種眼睛併發症的產生。由於多數患犬因過遲就診或確診，故就診時已失明相當長的期間，且已發生嚴重的其他種眼睛併發症，已無視覺恢復的可能性，手術對於這些病例之視力恢復幫助不大。但我們發現手術對於預防及治療其他種眼睛併發症（例如頑固性青光眼）及最近一週內失明者之視力恢復，有顯著的治療效果及幫助。故早期、正確地診斷及治療水晶體異位，對於改善該病治療後之預後情況，具關鍵性之重要地位。

關鍵字

水晶體異位 ； 水晶體囊內摘除法 ； 青光眼 ； 犬

並列摘要

Lens displacement is a common and potentially vision-threatening ophthalmic disorder in the dog. Fifty dogs suffering from lens displacement were presented at the National Taiwan University Veterinary Hospital (NTUVH) for ophthalmic examination and treatment. We used ophthalmic diagnostic techniques for determination of the severity and types of the 50 canine cases of lens displacement by performing slit-lamp biomicroscopy, indirect/direct ophthalmoscopy, and electronic applanation tonometry. Among the 50 canine cases examined, the sex ratio of the patients between males and females was 1: 1. The age distribution of the affected dogs was mainly within two respective ranges of 4-6 year-old and 9-11 year-old. The predominant affected dog breeds were crossbred/mongrel and Maltese (36% and 24% respectively). The ratio of bilateral to unilateral lens displacement was approximately 3:7. In totally 65 affected eyes, 28 eyes (43%) were anterior luxation, while 37 eyes (57%) were posterior luxation. Leading clinical presentation of these cases were blindness (91% of affected eyes), episcleral congestion (60%), blepharospasm (26%), corneal edema (15%), and conjunctival hyperemia (14%). Among the blind eyes, most cases (more than 50 eyes) were blind for at least several weeks to months. Concurrent ocular disorders included glaucoma (69%), cataract (66%), and uveitis (28%). We were able to confirm the etiology of the secondary lens luxation cases with obvious primary causes. However, we could not confirm the etiology of primary inherited form of the disease due to lack of family history and genetic background in those cases. Surgical management of the lens displacement by intracapsular lens extraction was performed in 42 cases. Because most of our lens displacement cases were diagnosed at an advanced stage with blindness and severe complications for a period of months to years prior to attending at our clinic, the vision was not restored in those cases with expected poor prognosis following surgery. Surgical management by lens extraction was found to be beneficial to prevention and treatment of other ocular complications, such as secondary glaucoma. In addition, surgery improved vision in recently blind eyes, particularly blind within one week. The overall prognosis of the cases in Taiwan was much poorer than those reported elsewhere due to late diagnosis in Taiwan. To improve prognosis of canine lens displacement in Taiwan, early diagnosis and appropriate management of lens displacement are critical and advocated.

並列關鍵字

Lens displacement ； Lens luxation ； Glaucoma ； Intracapsular lens extraction ； Dog