Spectrophotometric Analysis of Different Polymethyl Methacrylate Filters and their Importance in the Implantation of Corneal Rings

PURPOSE

This study evaluated the luminous behavior applied to materials used in intraocular surgeries.

METHODS

Discs of the different products were delivered in 19.00 mm × 3.00 mm. Each sample was fixed on support keeping it perpendicular to the spectrophotometer beam. Later, their analyses were carried out in the air/PMMA ratio. The graphs of individual profiles of the measurements along the length were constructed according to each of the filters from the spectrophotometric analysis. In addition, descriptive statistics of transmittance and absorbance for each wavelength presented were correlated for each filter.

RESULTS

It is possible to observe that the minimum absorption measure was found in the Red Filter, especially in the blue and green light spectrum.

CONCLUSION

Using filters in PMMA materials appears to improve visual quality in corneal implants, especially the red filter, due to greater absorbance of light leading to fewer light scattering phenomena through corneal rings. However, further studies comparing the effects of different filters on Intracorneal rings should be carried out to elucidate this field of study.

Piezoelectric 3D bioprinting for ophthalmological applications: process development and viability analysis of the technology

Piezoelectric inkjet 3D bioprinting technology is a viable technique for ophthalmological applications. It provides versatility, high sensibility and accuracy, required in ophthalmological procedures. A process flow for biofabrication was described in detail and validated, using piezoelectric inkjet technology, for ophthalmological applications, in vitro and in situ, based on complex images. Ophthalmological problems were documented by diagnostic examinations and were fed to the flow as complex images. The Concept Mapping methodology and the Conceptual Design approach were utilized to elaborate the 3D bioprinting process flow. It was developed a bioink with corneal epithelial cells. To simulate an in situ bioprinting process, eyes of pigs were selected as the substrate to print the cells. Print scripts used the digitally treated images. In order to print on predefined locations, alignment devices and sample holders were built. The proposed process flow has shown to be a potential tool for the biofabrication of ophthalmological solutions.