EyeWorld India September 2018 Issue

EWAP FEATURE 21 September 2018 Dr. Chan added that collabo- rating with good optometrists with expertise in fitting modern scleral lenses has helped these patients immensely and allowed some patients to defer surgery. “Collaborating with a medical transplant team of specialists has also helped me to successfully perform ocular surface stem cell transplants to rehabilitate those with severe limbal stem cell defi- ciency,” she said. “Those undergo- ing stem cell transplants from a cadaver donor or a living donor require systemic immunosuppres- sion and monitoring for potential side effects. Having the assistance of a medical transplant internist allows me to focus on the ocular surgery aspects of the patient's care.” Dr. Chan noted that the titanium backplate KPro has been shown in studies to have a lower rate of corneal melt, which is help- ful in these patients with severe dry eye and a poor ocular surface who are at high risk for melt. She also mentioned new treatments that could help such patients. In cases of acute Ste- vens–Johnson syndrome, amni- otic membrane should be placed across the lids, fornices, conjunc- tiva, and corneal surfaces along with a symblepharon ring in the acute phase of the disease as this can prevent much of the late stage sequelae that is such a challenge to manage later on, Dr. Chan said. “There are a variety of novel keratoprostheses in development across the world that may have fewer complications,” she said. Additionally, cultivated limbal stem cell therapy is expensive and challenging to replicate, but she thinks this technology will be better utilized in the near future. Pseudophakic bullous keratopathy According to Dr. Agarwal, some of the toughest cases to handle are the pseudophakic bullous kera- topathy cases with a bad cornea. He deals with this frequently and uses a specific management technique. “With more and more cataract surgeries happening all over the world, this complication is prevalent globally and is very challenging to treat,” he said. The reason it is hard to treat is because once a complication has occurred during cataract surgery, there is a vicious cycle of vitreous prolapse. Corneal decompensation, once started, becomes a nightmare, Dr. Agarwal said. The issue then is that the patient’s vision decreases, but a bigger problem stems from the corneal decompensation, which creates a lot of discomfort and finally scarring of the cornea starts. Views from Asia-Paci c Kauznori MIYATA, MD, PhD Hospital Director, Miyata Eye Hospital Assistant Professor, Department of Ophthalmology School of Medicine, Tokyo University Clinical Professor, Department of Ophthalmology School of Medicine, Miyazaki University F or severe ocular surface disease associated with limbal stem cell deficiency, retaining tear secretion is important. It is appropriate that as the first of a step-wise approach, Dr. Chan advocates optimization of severe dry eye. Improvement of tear secretion contributes to outcomes in later steps. For example, the use of a Boston keratoprosthesis type 1 necessitates intact tear production to prevent graft melting. Transplantation is effective when autologous stem cells are available, and is contraindicated in cases involving bilateral deficiency. For such cases, autologous cultivated oral mucosal epithelial transplantation (COMET) is used. For both stem cell transplantation and COMET, tear secretion is necessary. When tear secretion is lost, a Boston keratoprosthesis type 2 is used for limbal stem cell deficiency cases, but the success rate is low. The only current option for such cases would be an osteo-odonto keratoprosthesis (OOKP). “ Improvement of tear secretion contributes to outcomes in later steps. ” - Kazunori Miyata, MD, PhD Dr. Agarwal’s technique is appropriate and excellent. However, the severity of corneal opacity should be evaluated. I classify the severity of bullous keratopathy as follows: no significant corneal edema (G0), corneal edema with no visual acuity degradation (G1), corneal edema with visual acuity degradation and insignificant stromal opacity (G2), and irreversible stromal opacity (G3); then I determine an approach depending on the grade. For G1 and some G2 cases, treatment involves the use of corticosteroids or hypertonic saline eye drops. The corticosteroid could activate residual endothelial cells and hypertonic saline dehydrates stromal edema through osmotic pressure, resulting in reduction of edema. However, there is a risk of fungal infectionwith the long-termuse of corticosteroid. Dr. Agarwal’s techniques would be suitable for cases that are G2 or higher. The glued IOL and pupilloplasty allows structural stability of the anterior chamber, which would be effective in enhancing the success of DSAEK (Descemet stripping automated endothelial keratoplasty) and PDEK. Visual restoration with DSAEK and PDEK was unsuccessful in some G3 cases owing to stromal opacity. Additionally, it is difficult to observe the anterior chamber in most cases. For such cases, conventional penetrating keratoplasty should be considered rather than Dr. Agarwal’s techniques. Editors’ note: Dr. Miyata declared no relevant nancial interests. continued on page 22