contact lens focus

A Problem-Solver Lens

Lens offers solution for irregular cornea patients.

Corrie Pelc, Contributing Editor

The patient histories of two 16-year-old boys revealed irregular astigmatism, RGP lens wear and now soft toric lens wear due to RGP lens discomfort. Upon testing and questioning, the boys admitted difficulty seeing in their soft toric lenses and memorizing the Snellen eye chart to both prevent a RGP lens refit and secure their first driver’s license. Desperate to drive, the boys asked their new optometrists: “Can you please help me?” Optometrists Christine Cook, of Virginia Beach, Va. and Sheri Morneault-Sparks, of Simsbury, Conn., respectively, replied they would “try” with the msd Mini-Scleral Design lens, from Blanchard Contacts.

Overview

The msd (non-fenestrated and fenestrated in a 15.8mm or 18.0mm diameter) vaults the cornea and limbus, resting on the sclera. This is to correctly position its posterior surface, which blends reverse geometry with optical and posterior curves, over the irregular cornea. The result: instilled saline solution between the cornea and msd lens cancels much of the irregular and regular astigmatism of highly advanced keratoconus (oval and nipple), Blanchard Contacts says. Other msd applications: severe dry eye, keratoglobus, pellucid marginal degeneration, post-graft corneas and post-surgery corneal ectasia, Blanchard Contacts says.

“One of my patients had severe dry eyes that resulted in discomfort, and her best-corrected vision [was] 20/60 OD and 20/50 OS,” explains Victor Zaki, O.D., of Westford, Mass. “One week after wearing the msd, her vision improved to 20/20 in each eye, and her cornea healed completely.”

msd Mini-Scleral Lens

MATERIAL: Boston X0/Boston X02 DK/T:100 WEARING SCHEDULE: All waking hours RECOMMENDED REPLACEMENT SCHEDULE: 18 to 24 months DIAMETER: 15.8mm or 18.0mm SAGITTAL DEPTH VALUE: 3.60mm to 5.80mm MID-PERIPHERAL/LIMBAL ZONE POWER: Any EDGE CLEARANCE: 15.8mm: Standard, 1-Flat, 2-Flat. 18.0mm: Standard, 1-Flat

Dr. Morneault-Sparks adds the lens has enabled some of her corneal disease patients to postpone surgery.

In addition, the msd’s thin profile and design results in minimal lens edge/lid interaction, and it’s available in Boston X0 and Boston X0₂ high oxygen materials, enabling comfortable wear.

Fitting

The four steps to fit the msd lens:

1. Measure the msd’s sagittal (sag) depth. For steep corneas (>50.00D), for instance, Blanchard Contacts recommends starting with a 4.60 sag value lens from the msd diagnostic fitting set. (The required set [$650] contains 24 nonfenestrated lenses with eight sag values ranging 4.20mm to 5.60mm in 200-micron steps.) The ideal non-fenestrated msd fit is 200 microns to 350 microns of apical clearance above the highest corneal elevation, the company says. The ideal fenestrated msd fit: 100 microns to 150 microns. To ensure complete vaulting, the company recommends a white light optic section slit lamp evaluation to measure fluid depth behind the lens anterior to the cornea. Msd lens movement is similar to that of a soft lens, the company says.

2. Specify the msd’s mid-peripheral/limbal zone clearance (e.g. Standard – S, Decreased – D, Increased – I or Double Increased – II). (The diagnostic fitting set provides S and II mid-peripheral clearance zone values with each of the eight sag values within the set.) Should lens fogging occur, instruct patients to reinsert the msd with fresh saline in its bowl, Dr. Cook says.

3. Specify the msd’s peripheral edge zone value. For the 15.8mm lens, your choices are Standard, 1 flat and 2 flat. The 18.0mm lens: standard and 1 flat. (Each of the eight sag values within the 15.8mm diameter set has a standard and 1 flat peripheral edge lift value.) To order the 18.0mm diameter lens, increase the sag value 200 microns more than the 15.8mm lens you’re evaluating.)

4. Over-refract in normal light using handheld lenses for the final lens power. Start with 1.00D steps, and refine with 0.50D and 0.25D lenses, the company says.

Dr. Morneault-Sparks recommends obtaining training at Blanchard Contacts or through scleral fitting workshops at visioncare conferences.

All interviewed say most patients can accomplish lens insertion and removal in one visit.

“The most helpful tool for assisting patients with insertion and removal is a large, magnified mirror,” says Dr. Morneault-Sparks.

In addition to a mirror, Dr. Cook instructs patients to lean so their face is parallel to the floor, place the lens on a large DMV tool and fill the lens with saline. For removal, she has patients place a small DMV tool near the lens’ bottom portion to create suction.

Chair time/R.O.I.

The chair time for the msd Mini-Scleral Design lens averages one hour for the initial diagnostic lens fit, a half hour for the ordered lens fitting and a 15-minute one-week follow-up, says Dr. Zaki.

The practice cost: $195 per lens. Each lens retails for $400 to $600, depending on the practice. Fitting is reported with CPT 92313, and the lenses are reported with HCPCS V2531, says Dr. Morneault-Sparks.

“You get the same return on your investment as you get with the dispensing of other contact lenses because the fit is more expensive than other lenses,” Dr. Zaki explains. “In addition, I see several patients who have corneal abnormalities, so I’m using this lens quite a lot.”

“From a strict dollars and cents practice management angle, once you become experienced with the lens, which takes maybe five-to-six fits, you’ll cover your chair time with your fee that you’re reimbursed from an insurance company, and you’ll make money on the lenses themselves as well,” says Dr. Morneault-Sparks. “This is the case with other GP lenses too.”

Drs. Cook and Morneault-Sparks are quick to add, however, that they fit the msd to help patients, not their bank accounts.

For instance, those wily 16-year-old boys mentioned above are now driving.

“That young man was the very first patient I fit in the msd, and he and his mother literally had tears in their eyes because he said he could wear them comfortably,” says Dr. Cook. “Seeing that was very rewarding.” OM