Wavefront error maps (for a 9mm pupil diameter) in the right and left eye of the same cat at 8 weeks post-PRK, demonstrating the greater spatial irregularity of the wavefront in the control eye (bottom) compared to the eye treated with anti-TGFβ after PRK. While this effect was greatest at 2 weeks post-PRK, it was also maintained over the longer term.

A. Total higher order aberration (HOA) RMS. B. Coma RMS (RMS of all C_n^±1). C. Spherical aberration (SA) RMS (RMS of all C_n⁰). D. Residual HOA RMS (RMS of all C_n^≥|±2|). All graphs are plotting means ± standard errors of the mean as a function of post-operative time, with P=pre-operative time. * = significantly greater change from pre-op in controls than eyes that received anti-TGFβ treatment at that particular time-point (P<0.05). Note the peak in HOA, coma, spherical aberration and residual HOA exhibited by control eyes 2 weeks post-PRK. Except for spherical aberration RMS, anti-TGFβ treated eyes maintained pre-operative levels of higher order aberrations after PRK.

A. Spherical equivalent M. B. 0°/90° astigmatic component J0. C. 45°/135° astigmatic component J45. All graphs are plotting values expressed as dioptric power vectors M, J0 and J45 for a 6 mm pupil diameter as a function of post-operative time. All values are means and standard errors of the mean. On the horizontal axis, P=pre-operative time. Note that lack of significant effect of anti-TGFβ treatment on changes in lower order aberrations induced by PRK.

A-D. Images of the right eye (OD) of one cat treated with anti-TGFβ/Dexamethasone after PRK. Images were collected pre-operatively, 2, 4 and 12 weeks post-operatively, and demonstrate the radical change in reflectivity in this corneal region over time. E-F. Images of the left eye (OS) of the same cat, which only received vehicle solution following −10D PRK. Images were also collected pre-operatively, and then at 2, 4 and 12 weeks following PRK. Note the well-organized, regular syncitium of quiescent keratocytes pre-operatively and the disrupted, reactive and strongly reflective activated keratocytes and myofibroblasts that replace it postoperatively. Note also that the control eye exhibits much stronger reflectivity and cellularity than the anti TGFβ-treated eye, especially at 2 and 4 weeks post PRK.

Photomicrographs of corneal sections from a normal, unoperated cat and pairs of cat eyes that underwent PRK and received either vehicle or anti-TGFβ treatment post-operatively. These cats were sacrificed at 2, 4 and 12 weeks post-PRK and sections of their corneas were double-labeled with antibodies against αSMA to label myofibroblasts and with propidium iodide (PI) to label cell nuclei. Note the absence of αSMA staining in the operated cat cornea, in contrast with the significant αSMA expression in the sub-ablation stroma of eyes that underwent PRK. The band of αSMA expression was significantly thicker and more continuous in control eyes than in contralateral eyes treated with anti-TGFβ. It was also most intense at 2 and 4 weeks post-PRK, becoming almost absent in the stroma by 12 weeks-post-PRK. PI staining also revealed an area of increased cellularity under the ablation zone in all post-operative eyes, although cell density appeared consistently higher in control eyes relative to eyes treated with anti-TGFβ.

A-D. Images of the right eye (OD) of the cat in Fig.2, which was treated with −10D PRK and anti-TGFβ/Dexamethasone post-operatively, and demonstrating the radical change in reflectivity in this corneal region over time. E-F. Images of the left eye (OS) of the same cat, which only received vehicle solution following the −10D PRK. Images were also collected preoperatively, and then at 2, 4 and 12 weeks following PRK. Note the well-organized, regular syncitium of quiescent keratocytes pre-operatively, which contrasts with the less regular, reactive and strongly reflective activated keratocytes and myofibroblasts that replace it postoperatively, particularly in the control (left) eye. Indeed, the control eye exhibits much stronger reflectivity and cellularity than the anti-TGFβ-treated eye, especially at 2 and 4 weeks post-PRK. Note the spindle-shaped migratory fibroblasts (arrowed) and the cluster of reflective activated keratocytes in the right eye at 2 weeks post-PRK. Clustering is still present in anti-TGFβ-treated eyes 4 weeks post-PRK and is not seen in control eyes. As is evident in this set of images, control eyes exhibited greater cell density and greater reflectivity at this corneal depth than eyes treated with anti-TGFβ/Dexamethasone, at all post-operative time points.

A. Photomicrographs of feline corneal keratocytes cultured for 72 hrs in serum free defined medium supplemented with different concentrations of TGFβ. Cells are double-labeled with propidium Iodide (PI) and antibodies against αSMA (green). Note the strong αSMA immunoreactivity of cells exposed to 1 and 5 ng·mL⁻¹ _TGFβ. B. Western blots of feline corneal keratocytes cultured for 72 hrs in serum free defined medium supplemented with different concentrations of TGFβ. The left-most blot is a Coomassie stain demonstrating equal protein load in each lane. Lanes 1, 2, 3, 4 and 5 were loaded with keratocytes exposed to 0, 0.1, 1, 5 and 10 ng·mL⁻¹ of TGFβ respectively. Lane 6 was loaded with pure αSMA protein as a control. The right blot shows anti-αSMA staining of the same blot, and demonstrates increasing amounts of αSMA protein in keratocytes cultured with increasing concentrations of TGFβ. C. Photomicrographs of feline corneal keratocytes cultured for 72 hrs in serum free defined medium containing 1 ng·mL⁻¹ TGFβ and supplemented with different concentrations of anti-TGFβ antibodies. Staining was as in A. Note the strong αSMA immunoreactivity of cells cultured with 1 ng·mL⁻¹ TGFβ and up to 0.5ng·mL⁻¹ of anti-TGFβ. At anti-TGFβ concentrations of 1 or 1.5 ng·mL⁻¹, αSMA expression was strongly inhibited. D. Western blots of feline corneal keratocytes cultured for 72 hrs in serum free defined medium containing 1 ng·mL⁻¹ TGFβ and different concentrations of anti-TGFβ antibodies. The left-most blot is a Coomassie stain demonstrating equal protein load in each lane, as well as a reference ladder (leftmost lane). Lanes 1, 2, 3, 4 and 5 were loaded with keratocytes cultured for 72 hrs in serum-free defined medium containing 1 ng·mL⁻¹ TFGβ and 2.0, 1.5, 1, 0.1 or 0 ng·mL⁻¹ of anti-TGFβ antibody respectively. Lane 6 was loaded with pure αSMA protein as a control. The right blot shows anti-αSMA staining of the same Western blot, and demonstrates decreasing amounts of αSMA protein in keratocytes cultured with increasing concentrations of anti-TGFβ antibody.

A. OCT images of the left (OS) and right (OD) corneas of a cat before and 4 weeks after −10D PRK. Note the greater reflectivity in the sub-ablation stroma of the control eye (arrows) relative to the eye that received anti-TGFβ treatment post-PRK. The rectangles superposed over the corneal images indicate the location and approximate size of the areas analyzed for reflectivity and thickness. These analysis areas were located 1mm nasal to the center of each cornea and well outside the zone of the specular reflex. B. Plot of normalized backscattered light intensity obtained from the rectangular analysis areas in 25 OCT images of the left and right corneas of the cat shown in A versus central stromal depth, expressed as a percentage of the total stromal depth. 0% indicates the stromal/endothelial boundary, while 100% indicates the stromal/epithelial boundary. Reflectivity profiles are shown for both eyes of this cat pre-operatively and 4 weeks post-PRK. Note that the curves are relatively flat for both eyes pre-operatively, but that stromal reflectivity increases post-PRK. However, the eye that received anti-TGFβ treatments exhibits lower anterior stromal reflectivity than the control eye. C. Plot of the area under the reflectivity curve (see examples of these in B) for the anterior 20% of the corneal stroma as a function of time. Eyes that received anti-TGFβ treatment post-PRK exhibited lower mean reflectivity than control eyes at all post-operative time-points. D. Central epithelial thickness for control and anti-TGFβ eyes as a function of time. There was no significant difference between the two treatment groups. E. Central stromal thickness for control and anti-TGFβ eyes as a function of time, illustrating the consistently thinner stromas in anti-TGFβ treated eyes across post-PRK time-points. All graphs show means and standard errors of the mean.