本論文針對2003年至2005期間,於國立台灣大學附設動物醫院眼科門診203隻白內障患犬接受視膜網電波圖檢查之結果分析。視網膜電波圖儀為評估白內障患犬視網膜功能之工具,檢驗設備包括光刺激探頭、隱形眼鏡形狀平貼於角膜的紀錄電極,和置於眼角後3 cm皮下之針狀參考電極。動物於進行檢測前需局部投予散瞳劑,並且在暗視野下全身麻醉施行之。視網膜電波圖b波波幅若低於70微伏特(microvolt)則判定為視網膜功能受損。結果顯示有27%(109/402)受測白內障患犬眼波幅大小低於標準值,代表視網膜功能已存在局部或全面性的退化,其中包括9%(37/402)完全無波形與18%(37/402)為降低波形。雪納瑞、貴賓犬、博美犬與可卡犬等犬種之白內障患犬視網膜電波圖b波波幅檢測結果顯著低於混種犬,且達到統計學上之顯著差異,顯示這些犬種為視網膜退化的好發犬種。然而視網膜電波波形所產生的時間,在各犬種間並無顯著差異。在這些視網膜功能退化的犬隻當中,不同年齡對電波圖b波波幅有顯著的影響,而不同性別則無顯著差異。在本研究,73%白內障患犬的視網膜電波圖檢測結果為正常,並接受白內障摘除手術治療後,術後回診時視力均回復情形良好。基於本研究分析結果,我們提出以下結論:視網膜電波圖為白內障手術前重要之檢測項目,尤其對於視網膜退化的好發犬種,其優點在於當成熟白內障阻擋眼底檢查時視網膜電波圖可精準評估患犬視網膜功能,及協助預估手術後視力改善或回復的機率。
Pre-operative electroretinographic (ERG) data from 203 dogs with cataracts at the National Taiwan University Veterinary Hospital (NTUVH) were analyzed. Retinal function of the catatact dogs was examined by a RetinoGraphics ERG system with a white flash stimulus delivered to mydriatic canine eyes under general anesthesia. ERG was recorded by a contact-lens type of recording electrode referenced to a needle electrode inserted subcutaneously 3 cm posterior to the lateral can-thus. Abnormal ERG results with a wave amplitude less than 70 micorvolts were measured in 27% (109/402) of the eyes examined, including 9% (37/402) of eyes with absent responses and 18% (72/402) of eyes with decreased responses to light stimuli. Miniature schnauzer, Miniature poodle, Pomenarian, and Cocker spaniel showed significantly lower ERG b-wave amplitudes when compared to mix-breed dogs. There were no remarkable changes in the implicit time of ERG wave. There was a big difference in b-wave amplitudes between different age among dogs lost of retinal function, whereas there was no difference in gender among dogs lost of retinal function. In 73% of the dogs, ERG results were normal and cataract surgery was performed with good post-op visual prognosis achieved. As retinal diseases commonly affect dogs and the diseases greatly affect post-op visual outcome and success rate of surgery performed in cataract patients, ERG is an essential procedure before cataract surgery to select suitable candidates for surgical treatment of cataracts in animals.