Phthisis Bulbi Clinical Trial
Official title:
Comparison of Exposure Rate Between Local Made and Imported Porous Polyethylene Orbital Implant for Enucleation in Thailand: A Randomized, Equivalence Controlled Trial and Multicenter Study
This study wants to compare between two types of implants in enucleation. Both of them are made from porous polyethylene but have different fabricating techniques. The investigators chose an exposure rate as a main outcome because the investigators think it is the most important outcome for the surgeons. The study hypothesis is: Is the exposure rate of a local-made polyethylene orbital implant the same as an imported one?
Sample size assessment - The sample size was calculated by using an equivalence formula. From a literature and our own experiences, the success rate for Medpor and 3DP were 92% and 94% respectively, the difference (D) of the success rate between two groups was 10% and assuming a 15% of drop out rate. - Then allocation sequence was generated by a computerized program, using block of six with varying block size. Data management - All definition of data, recruiting techniques, data collection techniques and data management flow were mentioned in the SOP. - After double entry technique, each case record form from each site will be sent via DataFax system to the data center at Center of Excellence for Biomedical and Public Health Informatics (BIOPHICS), Thailand. - Then data will be validated, analyzed and reported by staff at BIOPHICS. Plan for missing data - by adding a drop out rate to the sample size calculation. - by choosing the right patients. Actually, Thai patients have good co-operation especially in surgical research. Statistical analysis - Intention to treat and per protocol model would be used to see the difference between two types of implants in this project. ;