As optometrists, we play an important role in increasing the likelihood of excellent post-surgical outcomes in our cataract patients by, in part, evaluating them for other ocular findings that could have a negative impact on their post-operative vision. Related diagnostic technology aids us in this endeavor.
In addition to acquiring a comprehensive medical history (e.g. presence of trauma, diabetes, etc.), the patient’s uncorrected and best-corrected VAs and glare testing to weigh the procedure’s risk to each patient’s vision, the following diagnostic technology should be employed:
A close evaluation of the lens on slit lamp examination with direct and indirect illumination is most common and necessary to aid in the assessment of the health of the ocular surface and adnexa, to confirm the cataract diagnosis and assess the capsule’s condition. Slit lamp biomicroscopy, in particular, aids in the assessment of the health of the ocular surface and adnexa. Should initial testing raise suspicion for DED, which causes tear film instability and a less-than-optimal refraction, additional related tools should be employed to arrive at a definitive diagnosis and a customized management approach. (See “Make the Ocular Surface Healthy," p.24, for additional information.)
Optometrists should perform binocular indirect or direct ophthalmoscopy of dilated pupils to determine that there are no retinal challenges that need to be identified.
RETINAL IMAGING DEVICE
Retinal imaging for retinal/macular pathologies is necessary to determine what limitations exist for BCVA. OCT, for example, enables the close evaluation of the macula, optic nerve and retina.
DARK ADAPTATION DEVICE
Dark adaptation testing tech-nology is used for our patients because research shows abnormal dark adaptation is a possible subclinical macular dysfunction marker in patients who have otherwise been deemed candidates for multifocal IOLs.
Tonometers aid us in diagnosing glaucoma in our cataract patients. Cataract patients who also have glaucoma may be at an increased risk for post-surgical IOP spikes and, thus, more vulnerable to ocular damage.
Additionally, those cataract patients who have moderate or advanced glaucoma are usually not good candidates for multifocal IOLs. The reason: Multifocal IOLs provide decreased contrast sensitivity, and glaucoma patients who have the moderate to advanced form of the disease typically already experience this decrease and don't want anymore of it.
As primary eye care providers, it is our duty to identify and share with our pre-surgical cataract patients any issues that may preclude a successful post-operative visual outcome.
Additionally, we should be prepared to help match patients to the IOL design that best suits our pre-surgical findings. (See "IOL Options," below.)
The diagnostic devices outlined above aid us in accomplishing this duty and, thus, managing our patients’ expectations. (See “Post-op Care Pointers,” p. 25.) OM
LINDSEY GETZ, CONTRIBUTING EDITOR
→ MATCHING PATIENTS with the right IOL is a critical aspect of cataract surgery. Beyond considering the refraction, O.D.s should consider details, such as the patient education required to succeed with the IOL. Here, Laura Huggins, O.D., of Bakersfield, Calif., and Damon S. Dierker, O.D., of Indianapolis, discuss these details:
- Ideal candidates. All patients, regardless of refractive error, who do not mind or, perhaps, even want to wear glasses partially or full-time post-surgery are ideal candidates, says Dr. Huggins. Dr. Dierker adds that these IOLs are typically the choice of patients who want only what insurance covers.
- Patient education on expectations. It must be made clear that patients will need glasses post-operatively, relays Dr. Huggins.
“Patients will, at least, need reading glasses for near,” she explains. “Depending on surgical aim and preoperative topography, some patients may need glasses for both distance and near following surgery. Glare and halos with night driving are expected to improve, but may not be gone completely.”
- Ideal candidates. Those interested in reducing their dependence on glasses and contact lenses and who have no other visually significant ocular pathology and well-controlled ocular surface disease are ideal candidates, says Dr. Dierker.
“This IOL is also best suited for those with an easy-going personality — not perfectionists,” he adds. “Avoid [recommending this IOL] to low myopes who like to take their glasses off to read.“
- Patient education on expectations. Dr. Huggins says to inform patients they may still need glasses for some tasks, such as reading, and will require good lighting for the best vision.
EXTENDED DEPTH OF FOCUS (EDOF)
- Ideal candidates. Patients who make the ideal candidates for multifocal IOLs, generally also make good candidates for EDOF IOLs, says Dr. Dierker. However, be cautious in recommending both EDOF and multifocal IOLs in patients who have had past laser vision correction surgeries. Further diagnostic testing, including corneal topography and wavefront aberrometry, may be needed to assess candidacy.
- Patient education on expectations. It’s important patients recognize these IOLs are not a guarantee to be glasses free, notes Dr. Huggins.
“Patients will note glares and halos post-operatively because of the IOL's optics, but to a lesser degree than multifocals,” she says. “Best near vision is expected at intermediate range. Good lighting is needed for the best vision, and small print may still require glasses.”
- Ideal candidates. “Hyperopic patients are better candidates,” Dr. Huggins says. “Myopic patients tend to expect post-surgical near vision to be similar to their pre-surgical near vision. These might work for patients who want to minimize the glare and halo side effects from multifocal and EDOF IOLs, but still want a small range of functional uncorrected vision at distance and intermediate distances.”
- Patient education on expectations. “This IOL allows patients some relative freedom from glasses at intermediate distances for quick tasks, such as reading price tags while shopping, reading gauges in a vehicle or reading menus at a restaurant,” says Dr. Huggins. “But the patient may need to wear reading glasses for near tasks and extended intermediate tasks, such as working on a computer.”
- Ideal candidates. Patients interested in reducing dependence on glasses and contact lenses and those with 1.00D or greater astigmatism make ideal candidates, says Dr. Dierker.
“The patient should be okay with reading glasses but want the best distance vision possible,” he adds. “Unlike with multifocal IOLs, patients can still benefit from a toric IOL if other pathology is present. For example: early macular degeneration or corneal Fuchs’ dystrophy.”
- Patient education on expectations. Patients should expect to need glasses post-operatively for the distance(s) that were not corrected with the IOL, says Dr. Huggins.
“The patient should expect ‘functional’ vision at a distance and for best-corrected distance visual acuity, he may still need a small distance prescription," she explains. "Glare and halos with night driving are expected to improve, but may not be gone completely.”
- Ideal candidates. “Myopic, hyperopic and astigmatic patients are all potential candidates," says Dr. Dierker.
- Patient education on expectations. Patients should understand the IOLs will allow good vision for most activities, but some glare and halos at night and may need a light prescription to see fine print, especially in poor lighting. OM
- Special thanks to Brittany Hoyle, O.D., for her assistance.