Surgeon uses medium-term perfluoro-n-octane without a scleral buckle for inferior, nasal, and temporal giant breaks as well as inferior retinal detachments.
Dr. Charles noted that if this is done carefully, usually going anteriorly can be avoided as the fluid is forced anteriorly. He uses medium term PFO for all inferior, nasal, and temporal giant breaks as well as all inferior retinal detachments.
If the breaks are nasal and temporal, the patients lies on his or her side postoperatively. Dr. Charles emphasized that the cavity is filled with PFO, using less is not as effective. A full fill results in less formation of small bubbles and the advantage, he noted, is that there is no exchange and, therefore, no slippage when managing giant breaks.
“The retina is put back where it belongs,” he said, adding that he has used this technique in pediatric patients with inferotemporal breaks, in whom the PFO was left in the eye for two weeks. In these patients, the lenses remained clear after 15 to 20 years.
An associated point is that vitrectomy does not cause cataracts, vitrectomy causes nuclear sclerotic cataract progression.
“The idea that medium-term PFO should not be used in phakic patients is nonsense,” Dr. Charles stressed.
Removing the PFO in 14 days is mandatory, because of development of a foreign-body reaction in some patients. He uses topical difluprednate twice daily in these cases unless the patient is a steroid responder.
Dr. Charles pointed out that he always excises the anterior flap in giant break cases to avoid its moving forward and causing epiciliary tissue and hypotony.
He again reemphasized the importance of completely filling the eye with PFO.
“To do this carefully in a phakic eye, the contact lens must be removed,” he said. “Go to the highest magnification right behind the lens, and very carefully remove the last layer of subretinal fluid, infusion fluid, and liquid vitreous that floats up to the top of the PFO to achieve a full fill.”
Dr. Charles also advises a PFO/gas exchange or a PFO/silicone oil exchange for a superior giant retinal tear; he uses silicone oil in eyes with proliferative vitreoretinopathy.
“The technique for the exchange is extremely important,” he said.
Under chandelier illumination, the silicone oil injection VFC is held in one hand and the extrusion cannula without a soft tip in the other hand to remove the PFO. Dr. Charles advises not using the soft-tipped cannula on the optic nerve head to avoid slippage; the cannula should be positioned at the top surface of the outer margin of the PFO.
This position at the periphery facilitates skimming off of any aqueous liquid and not PFO at the top surface. In a phakic eye, care must be taken to not touch the lens with the cannula. The surgeon must remain focused on the cannula tip during the exchange posteriorly to get the best view of the interface. This technique allows all the residual fluids to be removed before the PFO.
A novel tamponade
When performing an autologous macular patch graft, Dr. Charles uses a procedure developed by Tamer Mahmoud, MD, PhD, to address a macular hole that is under medium-term PFO. The PFO is removed after seven days. The PFO provides better oxygenation than silicone oil and enables the oxygenation from the anterior surface, not just the choriocapillaris.
Steve Charles, MD
E: [email protected]
This article is derived from Dr. Charles' presentation at the Academy of Ophthalmology 2019 annual meeting. Dr. Charles is a consultant to Alcon.