Avoiding Problems With the Microkeratome Miles H. Friedlander, MD, FACS
Avoiding Problems: Pre Op b Know your machine thoroughly Own your microkeratome or share it with a trusted friendOwn your microkeratome or share it with a trusted friend b Pachymeter before surgery Avoid thin corneasAvoid thin corneas b High or low K readings, may have to modify hinge or rings
Avoiding Problems: Pre Op b Use aximeter to mark line of sight b Make eccentric mark
Avoiding Problems At the Time of Surgery b Have pre incision check list and go through it personally Test motor,vacuum, rings, etcTest motor,vacuum, rings, etc “Trial run” before each case“Trial run” before each case
Avoid Problems At the Time of Surgery ( Cont.) b Be sure suction ring is correctly centered before applying suction Once vacuum is applied, the ring will always center over the same areaOnce vacuum is applied, the ring will always center over the same area b Check IOP before microkeratome cut b Check dry meniscus for IOP and diameter of cut
Difficulty Fitting Suction Ring to Eye b Check lid speculum (have variety handy) b Spread the speculum and “shoehorn” in b If above fails, do a lateral canthotomy
IOP Too Low b b Double check vacuum - if possible adjust b b Inject 4 cc anesthetic as a retrobulbar injection immediately before microkeratome pass
Epithelial Problems b b Disturbance of epithelium occurs in 10% of patients b b Use bandage contact lens post operatively
Avoiding Problems Time of Surgery b Microkeratome stops halfway Replace flap over bed and stop operationReplace flap over bed and stop operation Repeat after 3 monthsRepeat after 3 months
No Hinge b Replace cap b Single suture loosely tied b Remove suture next day
Hinge Too Large: Not Extending into Laser Optical Zone b Carefully hand dissect to reduce the size of the hinge
Perforation (Donut Shaped Cap) b More common with steep corneas and then caps b Place cap back on eye. b Approximate carefully b Bandage soft CL b Re-operate 2 + months
Replace Cap After Laser b Handle as little as possible b Irrigate under the flap b I like to aspirate b Be sure to align exactly. If not exact life up and reposition
Handling Cap (Cont.) b Not too much moisture or manipulation of the anterior surface b Keep epithelium on cap moist b Gently stroke from hinge nasal to temporal to avoids folds in Bowman’s
Cap Movement and Edema Next Day b Place anti-toric suture b Remove in one week
Anti-toric Suture
Irrigation and Aspiration
Thank You