PLANA VITRECTOMY IN POST-CATARACT SURGERY ENDOPHTHALMITIS IN CIPTO MANGUNKUSOMO HOSPITAL

Background: Endophthalmitis is one of the emergencies in ophthalmology and can cause blindness. The most common cause of endophthalmitis in intraocular surgery is cataract surgery. Immediate diagnosis and treatment can provide optimal final vision. This research aimed to describe the demographic data, and causative microorganisms, as well as the success rate of visual outcome after pars plana vitrectomy (PPV) in post-cataract surgery endophthalmitis in Cipto Mangunkusumo Hospital. 
Methods: A retrospective descriptive study of post-cataract surgery endophthalmitis underwent vitrectomy in Cipto Mangunkusumo Hospital, Indonesia, from January 2017 - June 2017. 
Results: There were twenty one cases of post-cataract surgery endophthalmitis undergoes PPV within the period of January 2017-June 2017. The most frequently identified causative microorganism was Staphylococcus (23%). There was an improvement of visual acuity after PPV procedure in 47,6% post-cataract surgery endophthalmitis. 
Conclusion: Immediate PPV is an effective treatment and leads to vision improvement in post-cataract surgery endophthalmitis. 
  
Keywords: pars plana vitrectomy, endophthalmitis, cataract surgery


Introduction
Endophthalmitis is an emergency that can cause blindness and requires immediate treatment to get better final visual acuity. The most common cause of exogene endophthalmitis is intraocular surgery, especially cataract surgery, which is about 90% of all cases of post-operative endophthalmitis. Although the incidence of post-cataract surgery endophthalmitis showed significant changes over time, Hesam et al. 2 reported that the incidence of postcataract surgery endophthalmitis varied between 0.04% -0.2%. Other study suggests that post-cataract surgery endophthalmitis has increased in the last two decades from 0.09% in the 1990 to 0.27% in the 2000. This increase is due to the increasing number of cataract surgeries in the world. 1 Pars Plana vitrectomy (PPV) in endophthalmitis aims to remove infectious material and vitreous debris so that it can eliminate the infection quickly.
2 PPV can immediately improve final vision and prognosis. Endophthalmitis Vitrectomy Study (EVS) found that cases with initial VA of light perception (LP) had improve final VA of 20/40 or better, and can reduce the poor final visual outcome by 50%. 5 This research aims to describe the demographic data, clinical characteristics, causative microorganisms and visual outcomes after PPV in post-cataract surgery endophthalmitis in Cipto Mangunkusumo Hospital.

Method
This is a retrospective descriptive study of post-cataract surgery endophthalmitis patients in Cipto Mangunkusumo Hospital, Indonesia, who underwent PPV from January 2017 until December 2017. The data was collected from post-cataract surgery endophthalmitis patient's medical records. The collected data, including demographic data, treatment methods, causative organisms, functional outcomes, and factors associated with improved visual outcomes, were retrospectively reviewed. The exclusion criteria were all other causes of endophthalmitis and patients with incomplete medical records. The patients were classified as "improved" visual outcomes when their final best-corrected visual acuity (BCVA) was better than initial BCVA. The collected data were then processed descriptively, and all variables presented in the table and graphic.

Results
Based on medical record data, there were twenty one post-cataract surgery endophthalmitis cases who underwent PPV in the period of January 2017 -December 2017.  In table 1, the majority of post-cataract surgery endophthalmitis patients have initial visual acuity (VA) ≤ 1/300 (85.7%) and the onset of cases occurred within ≤7 days (52.4%). Vx: vitrectomy; AB: vancomycin 0,1 cc + ceftazidime 0,1 cc; EL: endolaser; SO: silicone oil Table 2 summarized the treatment modalities and retinal condition. It describes that all cases were underwent vitrectomy and given intravitreal antibiotic injection. There were 9 (42.9%) cases of retinal necrosis and 12 (57.1%) cases of retinal detachment found upon PPV procedure.  Table 3 shows the results of culture is found Staphylococcus (23%). Candida albicans, Bacillus sp, Pseudomonas aeroginosa, and Aspergillus flavus were each found in 1 subject (6.3%).  Factors associated with visual outcomes were demonstrated in figure 2. It revealed that cases with presenting VA better than 1/300 could get better final vision after PPV procedure (50%). Cases with retinal detachment also showed an improvement in final VA after vitrectomy (50%). The onset and time of surgery could affect the visual outcome after vitrectomy.

Discussion
Acute endophthalmitis is a rare complication after cataract surgery, but it is an emergency in ophthalmology because it can cause blindness. 3 The incidence of post-cataract surgery endophthalmitis ranges from 0.03% -0.2%. 9,12 Research by Jeong et al. 14 reported the incidence of endophthalmitis after cataract surgery of 0.02% -0.08%. The increased incidence is due to an increase number of cataract cases that make cataract surgery the most commonly performed surgery worldwide. 3 The age range of post-cataract surgery endophthalmitis in this study was predominantly >60 years old (52.4%). Based on a study by Torabi et al. 8 , it was found that the average age of postcataract surgery endophthalmitis patients were 68.7 years

International Journal of Medical and Biomedical Studies (IJMBS)
old. Other study reported the age of patients at diagnosis ranged between 56-84 years old. 12 Age over 50 years old is a factor associated with poor outcomes in final VA. 13 Cases with presenting visual acuity better than light perception (LP) is a significant factor for achieving better final visual acuity. 10 In this study, it was found that cases with initial VA better than 1/300 could get improvement in final VA by 50%, while cases with initial VA worse than 1/300 only 2 out of 5 cases (40%) had better final vision. Jeong et al. 13 reported 52.4% cases have initial VA of 1/300 and 15.2% with initial VA of LP. The results of the regression analysis of the research found that poor initial visual acuity was a significantly related factor to poor visual outcome after PPV (odds ratio (OR): 1,114; 95% confidence interval (CI): 1,090-1,336; P = 0.004). According to study conducted by EVS, the initial VA of LP was a risk factor for the decrease of final visual acuity. 12 In this study, all cases (100%) were underwent PPV surgery and given intravitreal antibiotic injection. The use of intravitreal antibiotics aims to distribute antibiotics into the vitreous cavity. 5 Although EVS reported that immediate vitrectomy in endophthalmitis was only useful in cases with initial VA worse than LP, several recent studies have reported the benefits of immediate vitrectomy in cases of post-cataract surgery endophthalmitis. 5,13,14,15 In addition, Jeong et al. 14 reported that patients who only received intravitreal antibiotic injections more often required more procedure than those who had promt vitrectomy. Another factor affecting the improve of final vision is the time interval from onset to vitrectomy surgery. 13 PPV performed within <24 hours contributes to better visual acuity outcomes because it can immediately remove the infectious microorganisms thereby reducing the number of inflammatory cells. 13 According to this study, PPV performed within <24 hours had better final visual acuity by 66.7%.
Microorganisms on the eye surface can contaminate the aquos humor in 7-43% of cataract surgery cases. During cataract surgery, the posterior lens capsule should remain intact, but if there is a leak, it can increase the risk of endophthalmitis. 16 In this study, the culture result is found 50% of positive microorganisms.The most common isolated microorganism was Staphylococcus Epidermidis (23%). Other causative microorganisms were Candida albicans (6.3%), Bacillus Sp (6.3%), Pseudomonas aeroginosa (6.3%), and Aspergillus Flavus (6.3%). Other recent study also found that the most common microorganism was Staphylococcus epidermidis (77%). 17 Study by Das et al. 11 in India reported that 43.2% cases with positive cultures were found Streptococcus epidermidis. The causative microorganisms will affect the final visual acuity. Several studies reported that infection by gram-positive bacteria and negative cultures had better final vision. 5,13 The acute onset and progression of inflammation not only shows the immune host response to infection, but also describes the virulence of causative microorganism which is affecting final VA. Endophthalmitis, which occurs immediately after cataract surgery and develops rapidly, indicates infection by virulence microorganisms and is at risk of having poor visual outcome. 14 Most patients with post-cataract surgery endophthalmitis appeared with acute onset and within seven days after surgery, although in many cases it can occur later, especially in cases with causative agent such as fungal. 6,7,14 In this study, the onset were mostly found within <7 days (57.1%). Visual outcomes for those with onset ≤7 days 58.3% had better final VA, while cases with onset >7 dayss only 33.3% could get visual improvement.
The success rate of visual outcome after PPV in this study was 47.6%. Jeong et al. 14 reported a higher result of the improvement of final VA (20/40) reaching 51.8% after vitrectomy and intravitreal antibiotic injection. Other studies by Torabi et al. 8 and Gower et al. 18 reported final VA better than 6/60 after vitrectomy of 67.4% and 60%. This study shows the benefits of immediate vitrectomy to improve the final visual outcome even in cases with poor initial visual acuity. Therefore, prompt vitrectomy in postcataract surgery endophthalmitis is an effective treatment and can improve the prognosis of final vision.

Conclusion
Cataract surgery is the most common cause of exogen endophthalmitis. The functional visual outcomes of endophthalmitis after cataract surgery were 47.6%. The shorter time between onset and vitrectomy, causative microorganism, and initial visual acuity are significant factors associated with visual outcome after PPV surgery in post-cataract endophthalmitis. Although many factors affecting visual outcomes in post-cataract surgery endophthalmitis, prompt PPV is an effective treatment that can improve the prognosis of visual acuity.