***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: PURPOSE To evaluate postoperative corneal swelling as a predictor of corneal endothelial cell loss after phacoemulsification cataract surgery .  DESIGN Prospect i ve observational case series . METHODS Thirty patients planned for routine phacoemulsification cataract surgery were included .  Ultrasonic pachymetry and specular microscope endothelial photography of the central and nasal portions of the cornea and Orbscan II slit-scan tomography were performed preoperatively and the day after surgery . The 30 patients were selected from 41 patients based on their increase in  central corneal thickness : the first 10 cases with a < 5 % increase , the first 10 with a 6 % to 20 % increase , and the first 10 with a > or = 20 % increase . The same measurements were repeated after 1 , 2 , and 3 months . The primary outcome measures were corneal endothelial cell loss and increase in pachymetry . Several other parameters were also registered , including age , degree of cataract , visual acuity , phacoemulsification time and energy , total operation time , and the amount of infusion fluid used . RESULTS The central corneal swelling at postoperative day 1 was strongly correlated with the central corneal endothelial cell loss at 3 months ( R(2 ) = 0.785 , P < .001 ) . CONCLUSIONS In this series , with large variations in the corneal swelling at the first postoperative day , the degree of permanent corneal endothelial damage was reflected in the degree of early postoperative corneal swelling . Measuring the difference in pachymetry at postoperative day 1 is a useful way to assess the effects on the corneal endothelium exerted by the phacoemulsification procedure This study investigated whether diabetic-like corneal sensory deficits occur in the galactose-fed rat model of diabetic ocular complications and if such deficits could be prevented using either of two structurally different aldose reductase ( AR ) inhibitors , CT-112 or AL-1576 . S-D rats were r and omly grouped to receive a diet of Purina chow with either 50 % starch ( n=25 ) or 50 % D-galactose ( n=65 ) . Some of the galactosemic rats received either 0.25 % CT-112 topically 3x daily ( n=15 ) or 28 mg/kg body wt/day AL-1576 systemically ( n=10 ) . The control and untreated galactosemic rats in the CT-112 portion of the study received equivalent topical doses of the vehicle . Sensitivity measurements were made with a Cochet-Bonnet Aesthesiometer mounted on a micromanipulator . The filament was applied to the central corneal surface ( mean pressure of 0.96 g/mm2 ) and viewed using a slit-lamp biomicroscope . Ten consecutive stimuli were conducted on each cornea and the average number of blink-responses was expressed as a percent of total stimuli effected . Mean initial corneal sensitivities were similar in all groups . Corneal sensitivity in the galactosemic rat was reduced ( p<0.01 ) at each monthly measurement compared to control . Animals treated with CT-112 or AL-1576 showed a significant increase in the mean blink-response compared to untreated galactose-fed rats and did not differ significantly from controls towards the completion of the 7 month study . Animals treated with AL-1576 did not develop cataracts , whereas those treated topically with CT-112 and untreated galactose-fed rats developed bilateral nuclear cataracts within 3 weeks . This is the first study to demonstrate decreased corneal sensitivity in the galactose-fed rat model and its amelioration with AR inhibitors . Thus , aldose reductase , the first enzyme of the polyol pathway , may have an important role in the pathogenesis of decreased corneal sensitivity . The model could be useful for investigating the pathogenic mechanism(s ) involved in reduced corneal sensitivity associated with diabetic keratopathy in humans Purpose : To compare endothelial damage induced by different cataract incision sites and sizes using specular microscopy . Setting : Department of Ophthalmology , Hospital of San Donà di Piave , Venice , Italy . Methods : Eighty‐one eyes having phacoemulsification were r and omly assigned to 1 of 3 groups of 27 eyes each : 3.5 mm clear corneal incision ( CCI ) with silicone foldable intraocular lens ( IOL ) implantation ; 5.5 mm sutured CCI with poly(methyl methacrylate ) ( PMMA ) IOL implantation ; 5.5 mm scleral tunnel with PMMA IOL implantation . All incisions were centered at the 120‐degree semimeridian ; that is , they were superotemporal in right eyes and superonasal in left eyes . Noncontact specular microscopy was performed in the center and at the 12 o'clock position preoperatively as well as 1 week and 1 , 3 , and 12 months postoperatively . The endothelial cell density , mean cell area , cell size variation coefficient , percentage of hexagonality , and corneal thickness were considered . Results : Progressive endothelial cell loss and an increase in mean cell area occurred in all groups during the follow‐up . The cell loss percentages relative to the endothelial center appeared similar among the groups and slightly although not significantly lower in the scleral tunnel group . The scleral tunnel group had a statistically significant lower cell loss percentage at the 12 o'clock position than the 2 CCI groups at all follow‐ups . Conclusions : The scleral tunnel group had less postoperative endothelial damage than the 2 CCI groups , with a statistically significant difference at the 12 o'clock position . This is probably because the scleral tunnel incision is placed more posteriorly and therefore induces less direct and indirect endothelial trauma Purpose : To investigate the corneal endothelial cell density and morphology in patients with and without diabetes after phacoemulsification with intraocular lens implantation .  Methods : A clinical prospect i ve study including 30 patients with type 2 diabetes and 30 control patients without diabetes scheduled to undergo cataract surgery .  No difference in preoperative age was observed between the 2 groups ( P = 0.90 ) . Sample size was based on a power calculation ( power 0.90 ; P = 0.05 ) . The patients without diabetes had a casual blood glucose test performed to disclose undetected diabetes . The patients with diabetes had a serum glycosylated hemoglobin ( HbA1c ) test performed to reveal the glycemic control . The endothelial cell density , variation in endothelial cell size ( CV ) , percentage of hexagonal cells , and central corneal thickness ( CCT ) were recorded at baseline and at 3 months postoperatively . Results : The mean decrease in endothelial cell density at 3 months in the diabetic group was 154 cells per square millimeter ( 6.2 % ) and 42 cells per square millimeter ( 1.4 % ) in the control group . The difference in cell loss between the 2 groups was significant ( P = 0.04 ) . A significant decrease in the percentage of hexagonal cells was also seen in the diabetic group ( P = 0.01 ) . There was no statistically significant change in CV or CCT . Visual acuity increased significantly and equally in the 2 groups . Conclusions : The present study reveals a significantly greater loss of corneal endothelial cells in a diabetic group under good glycemic control , compared with nondiabetic group 3 months after phacoemulsification . The morphological changes in the endothelial cells in patients with well-controlled diabetes were not reflected in impaired function as judged by CCT Purpose : To evaluate intraoperative endothelial damage after planned extracapsular cataract extraction ( ECCE ) with different capsulotomy techniques and phacoemulsification . Setting s : San Carlos University Hospital , Castroviejo Institute , Madrid , Spain . Methods : In this prospect i ve , r and omized study , 60 patients with senile cataract scheduled for cataract surgery were divided into three groups of 20 each : Group 1 had phacoemulsification ; Group 2 , planned ECCE with continuous curvilinear capsulorhexis ; and Group 3 , ECCE with letter‐box capsulotomy . Preoperatively and 3 months postoperatively , endothelial cell density , percentage of hexagonality , and the cell size variation coefficient were determined by contact specular microscopy ; endothelial permeability was examined by anterior segment fluorophotometry and central comeal thickness , by ultrasonic pachymetry . Results were analyzed using the two‐tailed Students t‐test and analysis of variance . Results : In all three groups , endothelial permeability and cell loss increased significantly from the preoperative values , but there were no significant differences among the postoperative values . Mean cell loss was 11.8 % in Group 1 , 12.8 % in Group 2 , and 10.1 % in Group 3 . There were no differences between the preoperative and postoperative morphometric indexes . Postoperative pachymetric measurements were not significant . Conclusions : Endothelial response was not statistically significantly different among the surgical techniques , although endothelial damage was lower in Group 3 , which could indicate a protective effect of the anterior capsule during cataract extraction . Endothelial barrier function remained disturbed despite the apparent morphological stabilization Purpose : Cataract surgery is known to change the corneal endothelial cell density and morphology . In patients with diabetes , this change is more pronounced . This prospect i ve cohort study was conducted to assess and compare the endothelial cell loss and change in central corneal thickness ( CCT ) after manual small incision cataract surgery ( SICS ) in patients with diabetes versus age-matched patients without diabetes . Methods : Consecutive patients with diabetes ( 153 ) in the age group 40 - 70 years and age-matched patients without diabetes ( 163 ) undergoing manual SICS were enrolled . Preoperative and 1 week , 6 weeks , and 3 months postsurgery assessment s of corneal endothelial loss and change in CCT were done using specular microscopy and ultrasound pachymetry . Results : There was a steady drop in the endothelial density in both the groups postoperatively , with the percentage of endothelial loss at 6 weeks and 3 months being 9.26 ± 9.55 and 19.24 ± 11.57 , respectively , in patients with diabetes and 7.67 ± 9.2 and 16.58 ± 12.9 , respectively , in controls . The percentage of loss between 6 weeks and 3 months was found to be of significant difference ( P < 0.023 ) . In both the groups , an initial increase in CCT till the second postoperative week was followed by a reduction of CCT in the subsequent follow-up ( sixth week ) and a further reduction in the last follow-up ( 3 months ) . The change in CCT between the second and sixth weeks was significantly higher in the diabetic group ( P = 0.045 ) . Conclusions : The diabetic endothelium was found to be under greater metabolic stress and had less functional reserve after manual SICS than the normal corneal endothelium Purpose : To evaluate central endothelial cell loss ( ECL ) following clear corneal cataract surgery using two different incision sizes and the effect of ultrasound time ( UST ) and power on postoperative ECL and various cell parameters . Methods : Fifty‐eight patients had phacoemulsification through temporal , two‐step clear corneal tunnel incisions . In Group A ( n = 28 ) , a one‐piece , plate‐haptic , foldable silicone intraocular lens ( IOL ) was implanted through a 3.5 mm sutureless incision . In Group B ( n = 30 ) , a poly(methyl methacrylate ) IOL was implanted through a 5.0 mm incision with one radial suture .  The central endothelial cell counts were recorded preoperatively and postoperatively at 2 to 5 days , after 6 months , and after 1 year . Color‐coded , computer‐assisted specular microscopy was used for special cell analysis after 1 year . Results : Collective data showed an ECL of 7.9 ± 4.1 % ( mean ± st and ard deviation ) at 2 to 5 days postoperatively , 6.7 ± 2.9 % after 6 months , and 7.3 ± 3.3 % after 1 year . A direct linear relationship was found between ECL and UST and power : ECL increased as UST and power increased . After 1 year , ECL in Group A was 4.2 % with UST ≤1 1/2 minutes , 6.7 % with UST ≥ 1 1/2 to 2 1/2 min , and 9.6 % with UST > 2 1/2 to 3 1/2 min ; in Group B , it was 6.0 % , 7.5 % , and 11.4 % , respectively . Specular microscopy showed normal , age‐related cell parameters 1 year postoperatively . Conclusions : Phacoemulsification with 3.5 mm clear corneal incisions produced slightly less ECL ( 6.7 % ) than phacoemulsification with 5.0 mm incisions ( 7.9 % ) . Total ECL of 7.3 % at 1 year postoperatively compared favorably with ECL rates of other cataract extraction methods PURPOSE To investigate whether modern phacoemulsification surgery results in more damage to the corneal endothelium than extracapsular cataract extraction ( ECCE ) , and to examine which preoperative , operative , and post 
    Output:
    
Diabetic corneas are more vulnerable to stress and trauma , result ing in greater morphological abnormalities and longer recovery time