You might be wondering; what is the pre-operative assessment prior to cataract surgery done for a patient diagnosed with cataract? Why is it done? And what is the significance in cataract surgery?
On this page, you should hopefully be able to get a general idea about this assessment and its importance. Generally, the main goals that the ophthalmologist seeks to know from the assessment are:
- To determine whether the cataract is the main cause incriminated for the decline of vision or not.
- To assess whether the degree of decline of vision correlates with the cataract so as to determine whether lens removal will provide a significant improvement of vision or not.
- To evaluate the general health state of the patient and whether he can tolerate the surgery and anesthesia, or not.
- To ensure that the patient or another person (relative or a care giver) can handle the care needed for the patient after the surgery
- To come to a sure diagnosis as to whether the cataract is a primary condition, or is secondary to another systemic disease.
Assessment Of Patient’s General Health State
It is important to the ophthalmologist to inquire about certain diseases and medications that can have an impact on the result of the surgery, either directly, or indirectly.
These include:
- Presence of diseases like diabetes, or ischemic heart diseases may indicate an underlying ocular affectation playing role in the diminution of vision in addition to the presence of cataract. In such conditions, the patient has to be informed that he might still complain of decrease in visual acuity even after the operation.
- Diseases like bleeding disorders may necessitate the surgeon to modify the surgical techniques used, or take extra precautions to guard against bleeding during operation.
- Diseases like chronic inflammatory lung diseases may have an impact on the result of the surgery, as coughing is contraindicated after cataract surgery to prevent the IOL dislocation and displacement.
- Drugs like anti-coagulants may prolong bleeding if it happens during surgery.
- Drugs used in treatment of benign prostatic enlargement may cause a condition known as “intra-operative floppy iris syndrome”, in which the iris exhibits continuous motility and continuously changes its size. Knowing this fact allows the surgeon to take maximum precautions to ensure maximal dilatation of the iris during operation.
- The ophthalmologist has to inquire specifically about any known history of allergy to sedatives, anesthetics, and iodine (used during sterilization of the eye and face while preparing for surgery).
Past Ocular History
This includes asking about past medical conditions of the eye that may have an impact on the scheduled operation, influence the result of the surgery, or may lead to modification of the surgical technique to accommodate the current condition of the eye.
These include:
- History of trauma to the eye, past history of amblyopia, glaucoma or retinal diseases. All these conditions might have had a permanent effect on the patient’s vision. The patient in such case has to clearly understand that he might not regain an excellent vision even after cataract removal surgery.
- History of previous cataract surgery in the other eye. This helps the surgeon to accurately plan for the surgery including the most appropriate surgical technique to use, anticipate possible complications that might occur during surgery, and to be able to predict the outcome of the surgery based on the state of any previous surgery up to that point.
- History of previous refractive surgery done in the eye to be operated on for cataract. This is crucially important in determining the power of the IOL to be implanted in the eye.