ABSTRACT
Purpose: To study the intraoperative retinal macular morphology during macular surgery using handheld spectral domain optical coherence tomography (SDOCT). Design: Prospective, observational case series. Methods: A handheld SDOCT device was used to characterize the preoperative and intraoperative OCT images in 10 eyes of 10 patients undergoing vitrectomy for macular hole (MH) and epiretinal membrane (ERM). I intraoperative imaging was repeated after removal of the internal limiting membrane or the ERM and the images were analyzed. Results: Intraoperative SDOCT images from patients undergoing surgery (5 for full thickness MH including 2 previously failed surgeries and 5 for ERM were reviewed and quantitatively analyzed. In the 5 eyes undergoing surgery for MH, the minimum diameter of the hole showed a significant decrease (P = 0.031; the mean reduction 15.18%; range 6.14- 34.88%). Basal diameter increased in 2 eyes (mean change 9.96%), reduced in 2 (mean reduction 3.28%) while it remained unchanged in 1 case. The MH height decreased in 2 eyes (mean reduction 5.43%) and increased in 3 (mean change 20.04%). Intraoperative imaging in 5 eyes undergoing surgery for ERM revealed immediate decrease in retinal thickness in 3 eyes (mean change 5.00%), and increase in 2 eyes (mean change 17.76%). Comparison of the preincisional and intraoperative handheld SDOCT images demonstrated distinct changes in retinal macular morphology. Conclusion: The intraoperative use of handheld SDOCT provides a novel method for visualizing and quantifying changes in retinal anatomy during macular surgery. Further study is warranted to determine whether intraoperative macular morphological changes could affect and prognosticate MH closure.
ABSTRACT
Lovastatin, an inhibitor of HMG-CoA reductase, was produced by solid state fermentation (SSF) using a strain of Aspergillus terreus UV 1718. Different solid substrates and various combinations thereof were evaluated for lovastatin production. Wheat bran supported the maximum production (1458 ± 46 µg g-1 DFM) of lovastatin. Response surface methodology (RSM) was applied to optimize the medium constituents. A 2(4) full-factorial central composite design (CCD) was chosen to explain the combined effects of the four medium constituents, viz. moisture content, particle size of the substrate, di-potassium hydrogen phosphate and trace ion solution concentration. Maximum lovastatin production of 2969 µg g-1 DFM was predicted by the quadratic model which was verified experimentally to be 3004 ± 25 µg g-1 DFM. Further RSM optimized medium supplemented with mycological, peptone supported highest yield of 3723.4±49 µg g-1 DFM. Yield of lovastatin increased 2.6 fold as with compared to un-optimized media.