Eye Care
4. Ptosis Correction – 1 Upper Eyelid
Ptosis correction is usually completed under local anesthesia. The surgeon must make an incision in the drooping eyelid, and carefully advance and tighten the levator muscle, which elevates the upper eyelid. The eyelid is often carefully compared to the opposite eye in terms of lid height in awake patients, however, this is not possible in patients under general anesthesia (infants and young children). Once the lid height is secured in the desired location, the eyelid incision is closed with tiny sutures. One or both eyes may need to be treated.
Most patients will tolerate the procedure very well and have a rapid recovery. Cold packs may need to be applied to the operated eyelid for the first 48 hours following surgery. Antibiotic ointments applied to the incision are sometimes recommended. The elevation of the eyelid will often be immediately noticeable, though in some cases bruising and swelling will obscure this finding. Most patients will have sutures that need removing about a week following surgery. In children, absorbable sutures are often used. The bruising and swelling associated with the surgery will usually resolve in two to three weeks. Some patients may need adjustment of the sutures to better align the lid height. This may or may not require additional anesthesia or a trip to the operating room.
D. EYE MUSCLE CORRECTION SURGERY
1. Eye Muscle Correction (squint/strabismus)
Strabismus is ocular misalignment, which may be congenital or acquired; horizontal or vertical; comitant or incomitant. Exotropia (eye turns outward) or esotropia (eye turns inward) may also be corrected.
Strabismus surgery commonly entails recessions of eye muscles if weakening of muscles is required, and resections of eye muscles when strengthening of eye muscles is required. Recession of an eye muscle requires disinsertion of one of the six muscles attached to the eye, and reattachment of the muscle further back on the eye, thereby causing weakening. Resection of an eye muscle requires disinsertion of the muscle from the eye, excising a portion of the distal end of the muscle, and subsequent reattachment to the eye, thereby resulting in a stronger muscle. The amount that a muscle is recessed or resected is based on the pre-operative degree of misalignment of the eyes, which is measured by the ophthalmologist using prisms. In general, once a child develops manifest strabismus (obviously crooked eyes), there is no treatment which will “perfectly” straighten the eyes. The goal of surgery, therefore, is to realign the eyes as close to normal as possible, typically erring on the side of undercorrection.
1. Corneal Transplantation (penetrating keratoplasty)
Corneal transplant procedures may restore vision to otherwise blind eyes in some cases. There are many conditions in which corneal transplantation may be considered. The most frequent indication is pseudophakic bullous keratopathy, which is a corneal decompensation that occasionally follows cataract surgery. Pseudophakic bullous keratopathy may account for about 17% of all corneal transplant procedures. Less frequent indications include corneal ulceration, corneal scars, keratoconus, herpes simplex and Varicella zoster viral infections leading to scarring, Fuch’s endothelial dystrophy, congenital opacities of the cornea, and chemical burns of the eye.
A complete pre-operative evaluation will be required prior to surgery. The surgeon will make every attempt to confirm retinal and optic nerve function prior to surgery, so as to avoid cases in which visual improvement is unlikely.
The majority of adult patients may be operated on under local anesthesia. General anesthesia will likely be required for children, anxious, or uncooperative patients. After the anesthetic is given, the surgeon usually sews a ring to the ocular surface to support the eye. The donor cornea is prepared using a punch or corneal trephine to create the corneal “button.” The corneal button will become the transplanted cornea. The diseased, or scarred, cornea is then removed using a corneal trephine, creating a “bed” for the transplant cornea. Finally, the donor cornea is gently sewn into place with ultra-fine sutures (approx. one-third the thickness of human hair, or less).
Corneal transplantation may be combined with other procedures, particularly cataract extraction with intraocular lens implantation.
Postoperatively, patients should expect very gradual recovery of vision. In fact, the best vision may not be obtained for six to 12 months or more following surgery, even though vision may be improved from the first day after surgery in some cases. The surgeon will likely begin to remove some sutures from the cornea within a few weeks to a few months after surgery. However, all of the sutures need not be removed. In general, sutures are removed to help alleviate astigmatism once the cornea begins to show signs of being securely healed into place.
When glaucoma continues to progress despite the use of medication regimens and possibly laser treatments, a glaucoma filtration procedure (trabeculectomy) may be recommended.
The procedure is completed in the operating room, usually under local anesthesia. Some ophthalmologists will complete the procedure under topical (eye drop) anesthesia. On the day of surgery, one should expect to have several eye drop medications applied multiple times to the eye for approximately one hour prior to the procedure. Finally, the eye drop anesthetics or local anesthetic is applied just prior to the procedure.
Once in the operating room, your eye will be “prepped” for surgery with sterilizing solutions. Usually, a semi-opaque sterile drape will be applied over the operative field, using a small instrument to hold your lids apart for the procedure. Your eye should be entirely comfortable during the operation. Your surgeon may recommend mild sedation during the procedure, and this is usually determined on a case-by-case basis.The goal of the glaucoma filtration procedure is to create a new passageway by which aqueous fluid inside the eye can escape, thereby lowering the pressure. The filter, therefore, allows the drainage of fluid from inside the anterior chamber of the eye to a “pocket” created between the conjunctiva, which is the outermost covering of the eye, and the sclera, which is the underlying white anatomical structure of the eye. The fluid is eventually absorbed by blood vessels.
In many cases, medication to control scarring, and thus to help prevent closure of the filtration site, is applied to the eye during the operation or just afterwards. These medications, known as Mitomycin C and 5-Fluorouracil (5-FU), will be used in some cases and not others, depending on both surgeon and patient variables.
After Procedure
In most cases, a patch and shield will be placed over your eye on the day of surgery. This is usually removed later that day or the day after surgery and eye drop medications are begun. Your surgeon will usually want to evaluate your eye on the day of surgery or on the first post-operative day. At that time, depending on pressure in the eye, your surgeon might elect to cut sutures on the flap of the filter to modulate the filtration process. This is often done with a laser while in the office. Antibiotic and anti-inflammatory eye drop medications are continued after surgery for up to 6 weeks or more.
In some cases, the surgeon will apply additional medicines (e.g., 5-FU) to further prevent scarring and failure of the filter. Cutting of sutures may be completed up to several weeks after surgery, again depending on the degree of filtration noted at each office visit. In general, follow-up visits after filtration procedures are quite frequent, as often as every day or two shortly after surgery, with office visits decreasing in frequency as healing progresses.
