台灣犬隻頑固性青光眼不同治療方法的成效比較

Abstract

青光眼會造成患犬疼痛以及視力不可逆地受損，亦為犬隻進行眼球摘除手術的適應症之一。青光眼是一多因子的疾病，當眼房液生成增加或者排除受阻導致眼內壓上升，進一步影響眼內健康與視力時即可稱之。青光眼最佳治療方式仍有爭議性，部分學者認為手術介入對於眼內壓的控制有最直接的效果。破壞睫狀體的手術方式常被用於治療頑固性、對內科療法反應不佳的青光眼病畜。經鞏膜二極體雷射光凝術 (Diode laser transscleral cyclophotocoagulation, TSCP) 是一不具侵略性併發症較少的手術方式，近年來新興的治療方式為藉助內視鏡引導直接進入眼內燒灼睫狀體的內視鏡二極體雷射光凝術 (Endoscopic CPC, ECP)，由於後者被認為有更清楚的手術視野而漸受重視。 本研究的目的為回溯性分析自2004年1月1日起至2014年1月1日止就診於台灣大學動物醫院眼科門診與遠見動物眼科專科醫院之頑固性或末期青光眼的患犬，並探討不同治療方式的成效及術後併發症等。搜集資料後依照病畜選擇的治療方式區分為單純接受藥物治療 (Medical treatment only, MO)、經鞏膜二極體雷射光凝術 (TSCP)、內視鏡二極體雷射光凝術 (ECP)、眼內容物移除與人工義眼置換術 (Evisceration and intraocular prosthesis implantation, ISP) 以及眼球摘除術 (Enucleation, E) 共5個群組。針對僅接受藥物治療的青光眼患犬除了記錄其品種、性別、發病年齡、眼內壓數值、追蹤期長短與是否有其他眼科相關疾病外，亦記錄追蹤期間所給予的降眼壓藥物以及其預後；針對有手術介入治療的群組，其分析項目除了上述之外，再加入手術時的雷射設定與術後併發症的記錄。 本研究共計包含204隻犬、239隻末期青光眼被列入分析，患犬被列入研究時的年齡介於0.1至18歲 (平均8.9 ± 4.2歲)。品種分布方面共計有30個品種，出現頻率較高者依序為瑪爾濟斯 (39/204, 19.1％)、混種犬(35/204, 17.1％)、西施犬 (22/204, 10.8％)、柴犬 (15/204, 7.4％) 以及貴賓犬 (12/204, 5.9％)。共包括26隻已絕育公犬、49隻公犬、74隻已絕育母犬以及55隻母犬。平均追蹤期為480.8 ± 477.7天。原發性青光眼、繼發性青光眼以及因多重眼內病變無法確認青光眼病因者分別占106、102與31隻眼睛。在青光眼控制成功被定義為眼內壓下降幅度大於或等於20%且抗青光眼藥物的使用得以減少的條件下，MO、TSCP以及ECP群組的成功率依序為25.2％、57.1％以及92.9％。比較不同群組間成功率的相關性，MO與ECP群組的成功率有顯著差異性 (p value = 0.000 < 0.05)，而MO與TSCP群組的成功率則無顯著差異性 (p value = 0.061 > 0.05)。 TSCP、ECP、ISP與E群組的術後併發症機率依序為57.1％、64.3％、60.5％以及0％。術後併發症包括乾眼症、水晶體不全異位或異位、角膜潰瘍、眼球萎縮、眼內出血、角膜缺損、角膜肉芽反應以及角膜水腫。大多數的術後併發症皆為輕微且自限性的，在最後一次複診時皆能完全復原或得到緩解並未出現病畜眼睛不適的症狀。 ECP可能是一個針對頑固性末期青光眼患犬有效的治療方式。本研究中，相較於TSCP或MO群組，ECP可以顯著降低眼內壓並且減少術後抗青光眼藥物的使用。

Glaucoma is not only one of the leading causes of irreversible blindness and ocular pain in dogs but also the most common reason for enucleation in dogs. Traditionally glaucoma has been defined as a group of ocular diseases that exhibit increased levels of intraocular pressure (IOP) that are detrimental to the vision and health of the eye. The most successful therapy for control of glaucoma still remains debatable. Most veterinary ophthalmologists believe that surgery is the best route to reach a target range of IOP. Cyclodestructive procedures are usually reserved for cases of glaucoma that are refractory to medical therapy. Diode laser transscleral cyclophotocoagulation (TSCP) is a noninvasive procedure with a low complication rate. A newer method to directly photocoagulate the ciliary body under endoscopic guidance known as endoscopic CPC (ECP) has become an increasingly important and may have distinct advantages over the transscleral approach in eyes. The purpose of the study was to investigate the efficacy and complications of different treatments for dogs with persistent glaucoma presented to the ophthalmology clinic of the National Taiwan University Veterinary Hospital (NTUVH) and Vision Eyecare Center for Animals, Taipei from January 1st, 2004 to January 1st, 2014. The data was evaluated for breed, gender, and age at presentation. Medications for the glaucoma patients, prognosis for conservative and/or different surgical treatments (including TSCP, ECP, evisceration and intraocular prosthesis implantation, and enucleation) are also recorded. Efficacy and complications of different treatments for 204 dogs (239eyes) with persistent glaucoma were analyzed. The age of the dogs ranged between 0.1 and 18 years (mean 8.9 ± 4.2 years) . Thirty breeds were represented, with the five leading affected breeds being Maltese (39/204, 19.1％) , cross-bred (35/204, 17.1％) , Shih-Tzu (22/204, 10.8％) , Shiba Inu (15/204, 7.4％) , and Poodle (12/204, 5.9％) . The gender distribution was 26 neutered male, 49 intact male, 74 spayed female, and 55 intact female. The mean follow-up duration was 480.8 ± 477.7 days. Primary glaucoma, secondary glaucoma and glaucoma of unknown etiology was diagnosed in 106, 102 and 31 eyes, respectively. The success rate based on IOP reduction of 20% or greater with a decrease in the number of antiglaucoma medications from baseline at last follow-up was 25.2％, 57.1％, and 92.9％ respectively in medical treatment only (MO), transscleral cyclophotocoagulation (TSCP), and endoscopic cyclophotocoagulation (ECP) group. Statistically significant difference of success rate was found between MO and ECP group (p value = 0.000 < 0.05) but not between MO and TSCP group (p value = 0.061 > 0.05) . The complication rate of 57.1％, 64.3％, 60.5％, and 0％ was in the groups of TSCP, ECP, evisceration and intraocular prosthesis implantation (ISP) , and enucleation (E) group, respectively. Post-operative complications of these surgeries included keratoconjunctivitis sicca (KCS) , lens subluxation / luxation, corneal ulcer, phthisis bulbus, hyphema, cornea defect, cornea granulation, and cornea edema. The majority of complications were minimal and self-limited and recovered or relieved at last follow-up without signs of discomfort in treated patients. ECP may be an effective treatment for dogs with persistent glaucoma. In this study, ECP was associated with the greatest IOP control and marked decrease in the needs of prescribed antiglaucoma medications at last evaluation compared with MO or TSCP group.