There are 4 main goals in the preoperative evaluation of cataract surgery:
- Ensure symptoms are consistent with cataracts.
- Preoperatively identify and avoid potential sources of intraoperative complications.
- Clarify surgeon and patient goals regarding the course and outcome of surgery.
- Match the proper technology to the patient.
The best way to achieve these goals is by a complete ophthalmologic history and physical.
As cataract surgery has become safer with faster visual recovery and im- proved uncorrected visual outcomes, the risk/benefit ratio of this surgery has dramatically improved. As a result, we are relying on loss of visual function instead of visual acuity as the primary method of assessing the benefit of cata- ract surgery. Cataract surgeons, now more than ever before, must be diligent to ensure that the cataract is the cause (or at least partial cause) of the visual dysfunction. As discussed in Chapter 1, the appropriateness of cataract surgery for an individual patient may be the most important part of the pre- operative assessment. Each patient has individual visual needs, and surgery should be determined on an individual basis after an individual risk/benefit analysis.1,2 Documentation of the specific visual disturbance and impact on the patient is crucial. Because technology is improving, our ability to create spectacle independence is improving as well. Multifocal, accommodating, and toric intraocular lenses (IOLs) all require special testing and consideration but can leave patients much more functional without spectacles after surgery. Other technologies such as laser-assisted cataract surgery are just be- ing developed that may also improve outcomes and increase safety.
A. History of Present Illness
Pertinent features of the history of present illness include the patient’s age, symptoms, duration of symptoms, and impact on quality of life. Common symptoms of cataracts follow:
- ¤ Visual decline (blurred, clouded, a film, a skim) over weeks to years
- ¤ Glasses no longer improve eyesight
- ¤ Decreased distance vision, near vision, or both
- ¤ Decreased color perception (harder to distinguish blues and blacks,yellow is dim)
- ¤ Disabling glare
- ¤ Starbursts or halos around lights
- ¤ Worse during different periods of the day (day, dusk, and night)
- ¤ Monocular diplopia or polyopia
B. Ocular History
The ocular history includes both preexisting and concurrent conditions. Preoperative identification of these conditions allows the surgeon to give the patient realistic expectations, identify and avoid potential complications, suggest combined procedures, or suggest surgery be delayed or even avoided altogether.
1. Preexisting conditions that should be identified
- ¤ Amblyopia/strabismus
- ¤ Anterior basement membrane dystrophy, keratoconus, and corneal guttata
- ¤ Macular degeneration, epiretinal membrane, macular hole, and diabetic retinopathy
- ¤ Retinitis pigmentosa associated with posterior subcapsular cataracts and cystoid macular edema
2. Conditions with implications for cataract surgery.
The severity of the patient’s glaucoma should be understood. Would the patient’s optic nerve be able to withstand a perioperative intraocular pressure (IOP) spike? Would this patient be a better can- didate for a combined cataract and glaucoma procedure?3 Is the pa- tient using pilocarpine and will the pupils dilate intraoperatively? Recent studies have indicated that cataract surgery alone can create a significant and sustained reduction of IOP especially in patients with high preoperative IOP
Patients with uveitis are more prone to postoperative inflam- mation, cystoid macular edema (CME), epiretinal membrane, and posterior capsular opacification. A topical nonsteroidal anti-inflam- matory drug (NSAID) or steroid is necessary to control inflamma- tion prior to surgery. Often these patients have posterior synechiae leading to poor dilation (Figure 2-1).
c. High myopia
Patients with high myopia have a higher risk of retinal detach- ment after cataract surgery, and their periphery should be closely examined for breaks prior to surgery. They also may have posterior staphyloma, making IOL calculations difficult. In addition, there is a higher risk of globe perforation with retrobulbar anesthesia due to an elongated globe.
d. Prior retinal surgery
IOL calculation errors are more common in patients who have a scleral buckle. Patients who have had vitrectomy can have rapid progression of cataracts, and surgery is often more difficult due to loose zonules and posterior capsular instability.
e. Prior ocular trauma
Trauma can impact any intraocular structures and complicate the approach to surgery. It is very important to realize and anticipate that zonular instability may complicate these cases (Figure 2-2).
Pseudoexfoliation syndrome is well known to cause zonular in- stability, poor pupillary dilation, and increased risk of postoperative IOP spikes (Figure 2-3).
g. Prior refractive surgery
Achieving accurate postoperative outcomes is difficult in patients who have had prior refractive surgery because keratometric data are inaccurate. All cataract patients should be specifically asked about prior refractive procedures. Specific strategies to deal with these cases will be discussed in a later chapter.
h. Contact lens wear
Soft contact lens wearers must stop lens use at least 1 week prior to keratometry and rigid lens wearers 3 weeks prior to keratometry.
*Dikutip dari Buku Essentials of Cataract Surgery 2nd Ed, halaman 9-12