Look carefully at the picture and tell me what you would do differently for this cataract surgery. This patient has Fuchs’ Corneal Dystrophy and a visually significant cataract. When should we do cataract surgery alone versus doing cataract surgery combined with corneal endothelial transplantation?
An important preoperative measurement is the central corneal pachymetry, with a higher value indicating a more damaged and edematous cornea. As the endothelium weakens, these cells are unable to fully pump the water out of the cornea and the corneal stroma swells, thereby increasing the measured pachymetry. It has been suggested that corneas with a pachymetry of 600 µm or less would do well with cataract surgery alone, whereas those with pachymetry above 640 µm may benefit from a combined cataract surgery and endothelial transplantation.
• corneal pachymetry of < 600 µm can do well with cataract surgery alone
• corneal pachymetry of > 640 µm may benefit from combined cataract + endothelial transplant
This patient is fortunate to have a central corneal pachymetry of about 560µ which means that cataract surgery alone is a good option. In addition, this patient is 82 years old and desires a plano post-op refraction. This is quite reasonable and we aimed for just that. If the patient had a thicker, more edematous, cornea and was much younger, we would be more likely to anticipate a future endothelial transplantation and thus aim for a mild myopic outcome such as -0.50 to -0.75 to avoid hyperopia down the road.
Here are the steps of surgery that should be done differently:
- Protect the corneal endothelium with a good quality dispersive viscoleastic. In this video, we use tiny bubbles to visualize that the viscoelastic is still in position and actively protecting the corneal endothelial cells.
- Perform phaco within the capsular bag and avoid doing a supracapsular technique. The goal is to stay away from the corneal endothelium.
- Minimize the phaco ultrasonic energy by using phaco power modulations like burst and pulse modes. Use a narrow burst width and a shorter duty cycle in pulse mode.
- Adjust the phaco parameters to lower flow settings. We want to use as little balanced salt solution in the eye. In this case we used just 50 cc of fluid for the entire case.
- Control post-op inflammation by using steroids. In this case we also injected a small aliquot of preservative-free triamcinolone into the anterior chamber at the end.
Click below to see how we implement these changes in cataract surgery: