Clinical Feature And In Vivo Confocal Microscopic Findings In Patients With Posterior Corneal Stroma Opacity Of Unknown Aetiology

Objective:To observe and analyze the clinical feature and in vivo confocal microscopic findings in patients with posterior corneal stroma opacity of unknown aetiology.Methods:From June 2007 to November 2008,patients with grey-white,scurf-like opacities in the posterior corneal stroma found in routine health examination were observed in detail by slit-lamp biomicroscopy.They were graded by the degree of the opacity and futher examined by in vivo confocal microscopy(CM). We observed the morphological changes of stroma cell and matrix fiber and recorded the morphous,the density,the distribution and the depth involved by the opacity.We analyze the association between the density and the depth and further analyze the association between the degree of the opacity observed by slit-lamp biomicroscopy and the distribution of the opacity observed by CM.Results:146 patients(146/27688;0.53%) with posterior corneal stroma opacity were detected in routine health examination.Slit-lamp biomicroscopy showed small, evenly sized,grey-white,scurf-like opacities in the posterior corneal stroma.The middle and superficial layers were not involved.The stroma between the opacities was crystal clear.CM demonstrated highly reflective irregular dot-like deposits,distributed only in posterior corneal stroma.The mean size(±SD) of the hyperreflective dot-like deposits was 3.24±1.66μm.The middle and superficial layers were not involved.CM showed the extracellular hyperreflective deposits in 70.00%patients.The mean density(±SD) of the hyperreflective deposits was 24.16±18.73 deposits every piece.The mean stromal depth(±SD) involved by the hyperreflective deposits was 11.21±8.16μm.CM showed the extracellular and intracellular hyperreflective deposits in 30.00%patients.The mean number(±SD) of the stroma cells involved by the hyperreflective deposits was 2.41±1.28 cells.The mean stromal depth(±SD) involved by the hyperreflective deposits was 19.70±10.64μm,which showed much greater than the mean stromal depth (±SD) involved by the extracellular hyperreflective deposits.With the higher grade of the opacity observed by slit-lamp biomicroscopy,the intracellular hyperreflective deposits were more and the volume of the stroma cells involved was larger.The mean stromal depth(±SD) involved by the hyperreflective deposits examined by CM was positively correlated with the grade of the opacity examined by slit-lamp biomicroscopy(R=0.709,P＜0.01).Conclusions:People with posterior corneal stroma opacity of unknown causes found in crowd is firstly reported by this research and the incidence of posterior corneal stroma opacity is 0.53%.With the higher grade of the opacity observed by slit-lamp biomicroscopy,the intracellular hyperreflective deposits were more and the volume of the stroma cells involved was larger.CM is helpful to evaluate the depth,the severity and the morphological characteristics involved by the opacities.