ocular trauma has been a common reason of visual morbidity , which causes heavy psychological and economic burden to victims and society [ 13 ] . in the united states , there are approximately 2.5 million cases of eye trauma every year .
ocular trauma includes mechanical eye injury ( open globe injury and closed globe injury ) and nonmechanical eye injury .
it may have been caused by the rupture of the lens capsule or zonular ligament , the disorder of lens metabolism , or the oscillation of lens cortex caused by collision .
the occurrence of traumatic cataract could be observed immediately or several years after eye injury .
the shape of traumatic cataract may be total , local , rosette , or swollen or other irregular shapes .
the location of the opacity may be at anterior or posterior cortex or the capsule .
's study group that aims to predict the visual outcome of traumatic eyes , which has showed a predictable value for different types of ocular trauma [ 810 ] . and
recently some researchers have reported that the ots can indicate the final vision for traumatic cataract patients [ 11 , 12 ] .
has ots also been effective for traumatic cataract cases in central china ? to answer this question , we retrospectively reviewed the medical records of traumatic cataract in our hospital in the last five years and analyzed the data .
the medical records of traumatic cataract patients who received cataract surgery in our ophthalmic center from 2010 to 2014 were reviewed .
the retrieved information included age , gender , profession , causative agent , type of injury , initial visual acuity ( va ) after injury , diagnosis , treatment , and final va ( the best corrected va at the last follow - up ) .
the diagnosis and classification of ocular trauma in this paper are based on the birmingham eye trauma terminology ( bett ) which is a standardized ocular trauma definition and classification system for mechanical eye injuries [ 1315 ] .
the eye wound location was defined by the ocular trauma classification group : zone i , injuries limited to the cornea ; zone ii , injuries confined to the anterior 5  mm of the sclera ; and zone iii , injuries involving more than 5  mm posteriorly from the limbus .
the causative agents were divided into sharp metal items ( knife , scissors , forks , etc . ) , blunt injury ( fist , stone , toy , etc . ) , animal ( bite , hit , strip , etc . ) , electrical injury , chemical injury , and others . based on the injury condition ,
the cataract removal was performed in four different ways : phacoemulsification , extracapsular cataract extraction ( ecce ) not phacoemulsification , intracapsular extraction , or lensectomy . the intraocular lens ( iol )
might be implanted in the capsular bag , in the anterior chamber ( iris - clipped or placed on the lens capsule ) , or fixed in the ciliary sulcus .
the iol may be implanted at the first stage or second stage . during the surgery ,
the combined procedures include wound closure , tissue repair , foreign body removal , or vitreous or retinal operation .
the patients were followed up at 1 week , 1 month , 6 months , and 12 months postoperatively . for the enrolled patients , the follow - up was at least 6 months . at each follow - up , the corrected va was recorded .
the eyes were examined by slit - lamp microscope and direct ophthalmoscope . sometimes , an additional examination , like b - ultrasonography , ct , or mri , was needed .
the posterior capsular opacity was observed in some patients during follow - up , which could be treated by capsulotomy with laser or scissors . the ocular trauma score ( ots ) was first introduced by kuhn et al . in 2002 , which is a simplified system for standardized assessment and visual prognosis associated with eye injury .
the raw points of variables of each patient were calculated , summated , and categorized to different groups .
the potential va was compared with the actual va ; then , the sensitivity and the specificity of ots in each category were calculated .
the data were analyzed with spss software , version 17.0 ( spss , inc . ,
all values in our study were two - sided , and a value of less than 0.05 was considered statistically significant .
this study has reviewed the medical data of 480 cases of traumatic cataract from 2011 to 2014 . there were 324 males and 156 females ( x = 117.6 , p < 0.01 ) .
the age of patients ranged from 2 months to 83 years with an average of 41.5  19.3 years .
the average age is 40.9  17.7 for males and 42.1  16.8 for females .
there were 98 cases ( 20.4% ) under 14 years old and 41 cases ( 8.5% ) under 5 years old .
the professions were 191 peasants ( 39.8% ) , 165 workers ( 34.4% ) , 78 students ( 16.3% ) , and 46 cases ( 9.6% ) of other professions ( x = 159.0 , p < 0.01 ) in our study .
the causative agents included sharp agents ( 324 cases , 67.5% ) , blunt agents ( 82 cases , 17.1% ) , animal ( 29 cases , 6.0% ) , electricity ( 12 cases , 2.5% ) , chemicals ( 28 cases , 5.8% ) , and others ( 5 cases , 1.0% ) ( x = 1126.4 , p < 0.01 ) .
there were 437 cases ( 91.0% ) of mechanical injury and 43 cases ( 9.0% ) nonmechanical injuries ( x = 646.8 , p < 0.01 ) . in mechanical injury , there were open globe injury ( 354 cases , 73.8% ) and closed globe injury ( 83 cases , 17.3% ) ( x = 336.1 , p < 0.01 ) . among the open globe injuries ,
there were 255 cases ( 72.0% ) , 74 cases ( 20.9% ) , and 25 cases ( 7.1% ) with wound at zone i , zone ii , and zone iii ( x = 373.1 , p < 0.01 ) .
in nonmechanical injuries , there were chemical injury ( 28 cases , 5.8% ) , electrical injury ( 12 cases , 2.5% ) , and other types ( 3 cases , 0.6% ) ( x = 33.6 , p < 0.01 ) .
the cataract phacoemulsification was performed in 62 cases ( 12.9% ) , ecce was performed on 247 eyes ( 51.5% ) , cataract intracapsular extraction was performed on 123 eyes ( 25.6% ) , and lensectomy was performed on 48 eyes ( 10.0% ) ( x = 274.3 , p < 0.01 ) .
the iol was implanted in the capsule ( 177 eyes , 36.9% ) and in the ciliary sulcus ( 242 eyes , 50.4% ) or clipped at the iris ( 32 eyes , 6.7% ) ( x = 379.5 , p < 0.01 ) . there was no iol implantation in 29 cases ( 6.0% ) .
there were wound closure ( 356 eyes , 74.2% ) , pupillary formation ( 95 eyes , 19.8% ) , antiglaucoma surgery ( 87 eyes , 18.1% ) , vitreous surgery ( 56 eyes , 11.7% ) , retinal surgery ( 49 eyes , 10.2% ) , and others ( 92 eyes , 19.2% ) .
there were 75 eyes ( 16.2% ) with initial va of > 20/60 and 305 eyes ( 65.6% ) with final va of > 20/60 ( x = 235.0 , p < 0.01 ) .
the initial va was positively associated with final va ( r = 0.93 , p < 0.01 ) . for different professions ,
the final va of > 20/60 was in 122 eyes ( 64.2% ) in peasants , 110 eyes ( 67.1% ) in workers , 55 eyes ( 66.2% ) and 51 eyes ( 66.2% ) in students , and 22 eyes ( 62.9% ) in other professions ( x = 0.45 , p = 0.93 ) .
the final visual outcomes among different types were significantly different ( x = 27.6 , p < 0.01 )
. the final va of closed globe injury was better than that of open globe injury ( x = 10.1 , p < 0.01 ) .
in open globe injury , the final va of > 20/60 was found in 128 eyes ( 37.5% ) in zone i , 26 eyes ( 7.6% ) in zone ii , and 2 eyes ( 0.6% ) in zone iii .
the eyes with wound in zone i had better vision ( x = 22.7 , p < 0.01 ) than in other zones .
the patients with phacoemulsification had better va than those with other procedures ( x = 92.3 , p < 0.01 ) .
the results of final vision with different iol implantation procedures were shown in table 5 .
the actual and calculated ots of each patient were summated and analyzed . and the sensitivity and specificity were calculated and shown in table 6 . the sensitivities of ots predicting the va at nlp , lp / hm , and 20/40 were 100% .
this study has three parts : clinical features of traumatic cataract patients in central china , factors associated with visual outcome , and predictive value of ots .
shah et al . reported that the average age was 27 years [ 6 , 11 ] in india and serna - ojeda et al . reported that it was 46 years in mexico . in our study
, the ratio of males to females is about 2.1  :  1 , different from other reports with ratio 3  :  1 [ 16 , 17 ] .
in other researches , these percentages vary from 65.2% to 80% [ 6 , 11 , 16 , 18 , 19 ] . in our study , only 12.9% underwent phacoemulsification , which is much lower than the 96.3% reported by other researches .
this is because of the economic reason , to save money for patients . in our study ,
's report , 28% of the patients had hypertension complications after traumatic cataract . in our present study ,
65.5% of the eyes achieved a final va of > 20/60 and 49.8% of the eyes obtained va of 20/40 .
shah et al . reported that 54.3% of cases obtained va of > 20/60   and 31% of cases obtained va of 20/40 .
after treatment , the final va was much better than the initial va statistically in our results .
treatment for traumatic cataract is different from senile cataract although most cataract procedure steps were similar .
first , the wound should be treated before the cataract in open globe injury , like eyelid , corneal or scleral wound , and lacrimal apparatus injury .
second , the traumatic cataract operation always is more complicated than the traditional cataract operation . in some cases ,
the posterior capsular rupture was much more common in traumatic cataract surgery than in conventional cataract operation .
as kuhn reported , traumatic cataract procedure is an individualized , consciously made decision regarding what to do and when and how to do it to achieve the best possible outcomes .
the possible factors which may influence the final va were initial va , injury type , wound location , cataract removal procedure , and the way of iol implantation .
the initial va was also the predictor for visual outcome in open and closed globe injuries [ 1 , 2 ] . ( 2 ) the final va of open globe injury was better than that of closed globe injury .
( 3 ) the location of the wound in open globe injury will influence the vision .
this is because the retina is located at the posterior part of the eyeball , which is the vital part for visual message transition .
( 4 ) the patients who underwent different cataract removal procedures had different visual outcomes .
phacoemulsification usually needed better operational conditions , like stable anterior chamber , complete capsular bag , and sufficiently strong suspensory ligament . for patients with broken capsule , ecce or other methods
iol implanted in the capsule is the ideal position for vision . for patients without complete or enough capsules ,
reported that ots may provide prognostic information in deadly weapon - related open globe injuries .
unal et al . reported that ots provided reliable information about the prognosis of deadly weapon - related open globe injuries with intraocular foreign bodies .
uysal et al . reported that ots might provide prognostic information in children with open globe injuries .
ots also had a good predictive value in firework - related eye injuries   and closed globe injuries . about the predictive value of ots on traumatic cataract in children , zhu et al .
have reported that ots has a high ability to predict visual outcome for pediatric traumatic cataract following penetrating ocular trauma .
shah et al . also reported that ots was a reliable predictor of the final vision of pediatric traumatic cataract .
there was only one reference that mentioned the value in traumatic cataract in adults and children .
shah reported that ots was found as a reliable tool to predict visual outcome in traumatic cataracts 6 weeks postoperatively .
our paper has observed the long term of final va of cases to evaluate the predictive value of ots for traumatic cataract patients in long - term follow - up .
and the ots had high predictive sensitivity and high specificity for traumatic cataract patients in the long term . in conclusion
, our paper has found five factors influencing the final va : initial va , injury type , wound location , cataract removal procedure , and iol implantation method .
the ots has high sensitivity and specificity for predicting visual outcome of traumatic cataract patients in long - term follow - up .
 
 purpose . to investigate the prognostic factors for visual outcome in traumatic cataract patients 
 . methods . the demographic features of traumatic cataract patients in central china were studied . 
 the factors that might influence the visual outcome were analyzed . 
 the sensitivity and specificity of ots ( ocular trauma score ) in predicting va were calculated . 
 results . 
 the study enrolled 480 cases . 
 65.5% of patients achieved va at > 20/60 . 
 the factors associated with the final va were initial va , injury type , wound location , the way of cataract removal , and iol implantation . 
 the sensitivities of ots in predicting the va at nlp ( nonlight perception ) , lp / hm ( light perception / hand motion ) , and 20/40 were 100% . 
 the specificity of ots to predict the final va at 1/200 - 19/200 and 20/200 - 20/50 was 100% . 
 conclusion . 
 the prognostic factors were initial va , injury type , wound location , cataract removal procedure , and the way of iol implantation . 
 the ots has good sensitivity and specificity in predicting visual outcome in traumatic cataract patients in long follow - up . 
1. Introduction 
2. Methods and Patients
3. Results
4. Discussion