Nictitating membrane resection in the horse: a comparison of long-term outcomes using local vs. general anaesthesia.

The study evaluates if the type of anesthesia, local or general, impacts the recurrence of eye cancer in horses after the surgical removal of their nictitating membrane (a transparent or translucent third eyelid found in certain animals). It concludes that the anesthesia method has no significant effect on cancer recurrence and that the procedure has no harmful long-term effects on the horses’ eye health.

Study Goals and Methodology

The primary aims of the study included:

• Assessing long-term complications associated with the resection of the nictitating membrane in horses.
• Evaluating the rate of recurrence in horses after surgery, based on whether local or general anesthesia was used.
• Determining the impact of anesthesia choice on disease recurrence post-surgery.

To achieve these goals, the researchers reviewed the records of 26 horses that underwent the resection procedure due to primary neoplasia (new and abnormal growth of tissue) between 1999 and 2009. They recorded details like examination findings, the surgical process, anesthesia type, pathological findings, and any additional treatments given. They also contacted the horses’ owners to gather information on post-operative outcomes. The data was then analyzed using Fisher’s exact test.

Findings of the Study

The study concluded that:

• The common long-term side effect of nictitating membrane resection was a mild ocular discharge.
• Squamous cell carcinoma, a type of skin cancer, was the most frequently diagnosed disease in the histopathological results.
• On a rare occasion (2 out of the 26 horses studied), there was a recurrence of neoplasia.
• No noteworthy difference was found in neoplasia’s recurrence rate between horses receiving general anesthesia versus local anesthesia.

Conclusion and Implications

The study asserts that there are no significant differences in the recurrence rates of neoplasia in horses whether the surgery was performed under local or general anesthesia. Furthermore, the removal of the nictitating membrane in horses does not associate with any harmful ocular side effects in the long run. The findings suggest that this surgical procedure can effectively treat primary neoplasia of the nictitating membrane in certain cases. It can help veterinarians choose the appropriate anesthesia for operations and provide info about potential long-term outcomes.