1. Miguel A. López M.D., María A. González Reiley M.D. The authors have no financial interest in the subject matter of this poster.

2. Biography  Miguel A. López M.D.  Cornea Department Head, Hospital Dr. Elias Santana, Santo Domingo, DR.  Education: Universidad Autónoma de Santo Domingo (UASD) Residency: PG-1 General Surgery - Hosp. Dr. Salvador B. Gautier Ophthalmology Residency - Hosp. Dr. Elías Santana. Fellowship: Cornea, External Eye Diseases and Refractive Surgery -Mass. Eye & Ear Infirmary, Harvard Medical School.  Sociedad Dominicana de Oftalmología: Member and President 2004-2005.  American Academy of Ophthalmology (AAO): International member.  American Society of Cataract and Refractive Surgeons (ASCRS): International member.  Pan-American Association of Ophthalmology: Member.

3. Biography  Maria A. González Reiley M.D.  Fellow of Cornea, External Eye Diseases and Refractive Surgery, Hospital Dr. Elias Santana, Santo Domingo, DR.  Education: Universidad Central de Venezuela (UCV) Ophthalmology Residency: Hospital Dr. Domingo Luciani, UCV, Caracas, Venezuela. Fellowship: Cornea, External Eye Diseases and Refractive Surgery - Hospital Dr. Elias Santana, Santo Domingo, DR.  Sociedad Venezolana de Oftalmología: Member.  American Society of Cataract and Refractive Surgeons (ASCRS): International member.

4. Purpose  The chemical burn is a frequent pathology seen in the Dominican Republic after assault or crimes of passion that causes blindness in most cases.  To evaluate the visual outcomes, follow up and complications of PMMA Keratoprosthesis (KPro) in patients after severe chemical burn at our institution.

5. Patients and Methods  Retrospective case series study.  Inclusion criteria: patient with chemical burn grade 4 who had PMMA Keratoprosthesis implantation in Elias Santana Hospital between June 2006 to July 2009.  Exclusion criteria: posterior segment pathology that affected retina or optic nerve.

6. Patients and Methods  Variables: age, sex, eye operated, uncorrected distance visual acuity in logMAR pre-op and post-op until 3 years, post-op complications (Dellen, corneal melting, retroprosthetic membrane, iris displacement, device extrusion).  Statistical analysis: Descriptive analysis used median and percentile for continual variables. Percentage for qualitative variables. Bivariable analysis used paired Wilcoxon analysis for statistical significant difference in visual acuities pre and post- op. Lineal multivariable regression to find association between visual acuities and complications in the first year post-op.

7. Results Table 1: Demographic and Affected Eye Baseline Characteristics NumberPercentile of PatientsPercentageMedian2575 Age (years) 282538 Sex Male 1689% Female 211% Eye studied Right 950% Left 950% UDVA* Presurgery (LogMAR) 2.623 UDVA* Presurgery (CF† & HM‡) 1 CF†3 CF†HM‡ * (UDVA) Uncorrected distance visual acuity, † (CF) Counting Fingers, ‡ (HM) Hand Motion

8. Results Figure 2: Postoperative Complications Retroprosthetic membrane was the more common post-op complication (75%), follow by corneal melting (35%), Iris displacement and device extrusion (18%) and corneal dellen (15%). Corneal melting was associated with a higher impaired UDAV at first year post-op (linear multivariable regression p= <0.05).

9. Results Figure 1: Uncorrected Distance Visual Acuity long-term changes Median UDVA was 2.6 LogMAR preoperative and after PMMA Keratoprothesis median UDVA was between 0.7 and 1.0 LogMAR, that keep up until 3 years after the surgery. This indicate significant visual improvement at the first day postop (Paired Wilcoxon Test p=0.001), with no significant difference between the 1st day and the 3rd year (Paired Wilcoxon Test p=0.89).

10. Conclusions  PMMA Keratoprosthesis improve visual outcomes for 3 years in patients that otherwise had poor prognosis.  Almost all cases of PMMA K-pro have good device retention.  Corneal melting was the principal factor of impaired UDVA and an adequate contact lens is important to avoid it.  Patient education is important to decrease complications.