Intrastromal keratopigmentation: a boon for unsightly corneal scars

PURPOSE

The aim of this study was to improve cosmesis in patients with corneal opacity (CO) using newer organic micronized pigments.

METHODS

Settings: Tertiary Care eye center, Design: Retrospective study.

INCLUSION CRITERIA

Patients with unsightly corneal scars not suitable for keratoplasty, eccentric corneal opacity not requiring keratoplasty, or lenticular opacity/anterior or posterior capsular opacities in non-seeing eyes. Micronized organic pigment was used for keratopigmentation by the intrastromal pocket technique (ISPT) in deep corneal opacities and lenticular opacities, whereas the intrastromal needle puncture technique (ISNT) was used in superficial opacities or corneoiridic scars. The records of 463 patients were reviewed and analyzed for the duration of the past 7 years.

RESULTS

Two hundred and ninety-three (63.2%) patients underwent ISNT, eight underwent combined technique, and the rest underwent ISPT. The postoperative follow-up period showed more watering and redness in the needle puncture technique (p > 0.001), which resolved in 70.4% of patients by the end of 4 weeks. Repeat procedures were required in 5.3% of the patients with ISNT. The patient's satisfaction grading showed excellent levels in 375 (80.9%) patients, 45 (9.7%) had good satisfaction levels, and the rest had average satisfaction levels.

CONCLUSION

Intrastromal keratopigmentation is a boon for unsightly corneal scars and gives respite to the patients from the social stigma.

Suppressing aggregation of quinacridone pigment and improving its color strength by using chitosan nanofibers

Quinacridone, a red pigment, is prone to aggregation, which results in undesirable color changes. Cellulose nanofibers (NFs) have been reported to adsorb quinacridone and suppress its aggregation. In this study, we investigated the potential of chitin and chitosan NFs which possess acetoamide and amino groups, as a quinacridone dispersant. Chitosan NFs, obtained by fibrillation using high-pressure homogenizer, adsorbed more quinacridone than cellulose NFs. SEM observations showed that chitosan NFs inhibited the aggregation of quinacridone, but chitin NFs did not. NMR analysis suggested the hydrogen bonding between chitosan NFs and quinacridone induced by the amino groups. The results indicated that the amino groups more facilitated the intermolecular interactions between NFs and quinacridone than the hydroxyl groups whereas the acetamide groups hindered them. Color measurements showed that the redness of quinacridone improved when cellulose or chitosan NFs were added. Chitosan NFs were found to be a novel candidate for quinacridone dispersants.