ABSTRACT

Conclusion:

Immediate sequential bilateral vitrectomy surgery can be considered an option for patients with active bilateral stage 4 and stage 5 ROP. The risk of endophthalmitis should be weighed against the risks of disease progression and anesthesia-related complications.

Results:

Seventy eyes of 35 babies who had immediate sequential bilateral vitrectomy surgery for stage 4 or stage 5 ROP were reviewed. At the time of surgery, the mean age was 41.4±4.9 weeks. There was preoperative plus disease in 58.6% of the eyes. The mean surgery/eye ratio was 1.2. Mean anesthesia time was 95±64 minutes. The mean follow-up was 28.1 months (3 to 84 months). Anatomical success was 95.7% for stage 4A (44/46 eyes), 83.3% for stage 4B (15/18 eyes), and 50% for stage 5 (3/6 eyes) ROP. Patients with stage 5 ROP had significantly less anatomical success than stage 4A and 4B (p=0.004). None of the patients had endophthalmitis and anesthesiarelated severe complications.

Materials and Methods:

Babies who had immediate sequential bilateral vitrectomy surgery for stage 4 or stage 5 ROP were included in this retrospective study. Clinical history, demographic characteristics of the patients, surgical procedure details, perioperative and postoperative ophthalmic and systemic complications, and postoperative anatomical success rates were evaluated. General anesthesia features were also recorded.

Objectives:

We report the safety and efficacy of simultaneous bilateral vitrectomy for stage 4 and stage 5 retinopathy of prematurity (ROP).

Introduction

The incidence of retinopathy of prematurity (ROP) is increasing with advances in neonatal care.¹ Even with careful screening and treatment, ROP still progresses to stage 4 or 5 and needs surgery in 12% of eyes.² Treatment for stage 4 and stage 5 ROP includes scleral buckling and vitrectomy with or without lensectomy.^3,4,5,6,7 Lens-sparing vitrectomy (LSV) in stage 4 and 5 ROP offers the greatest hope for visual rehabilitation of the phakic eye, but the decision to proceed with surgery must be weighed against the risks of iatrogenic retinal breaks and surgical aphakia, complications that have more significant consequences for infants than for adults.^8,9

The timing of surgery for ROP should be planned carefully. Early intervention when the eye is highly vascularized can have as devastating results as waiting too long for the eye to become quiet.^{10,11,12,13,14} The ideal timing for vitrectomy is when vascular activity is reducing and retinal detachment is beginning.¹¹ When both eyes show similar findings and need immediate surgery, waiting for days or weeks between eyes might lead to blindness in the latter eye in high-risk ROP cases.^11,15,16 Furthermore, general anesthesia-related complications increase in preterm babies when anesthesia is repeated after a short interval. Both of these factors encourage performing bilateral surgery in the same session (i.e., immediate sequential bilateral vitrectomy surgery).^{11,13,16,17,18,19,20,21,22}

Here, we present our experience with immediate sequential bilateral vitrectomy surgery (ISBVS) for stage 4 and 5 ROP cases.

Materials and Methods

Results

Discussion

ISBVS in ROP can be rationalized in many ways. The patients are infants with many comorbidities, including bronchopulmonary dysplasia (BPD), which increases the risk of anesthesia administration and sometimes makes it impossible to repeat anesthesia.^17,18,19,22 Infants with BPD have especially high risk of developing respiratory problems such as bronchospasm and atelectasis in the perioperative period.²³ Additionally, when there is active ROP in both eyes, delaying surgery in the second eye may not be feasible.¹⁵

Bilateral simultaneous cataract surgeries in pediatric patients have been previously reported.^20,21,24,25 Postoperative endophthalmitis is the most frightening complication after bilateral simultaneous intraocular surgeries. Previous studies reported endophthalmitis rates in pediatric and adult cataract surgery between 0.15 and 1.1%.²⁵ The endophthalmitis risk after adult vitreoretinal surgery is reported to be between 0.03% and 0.08%.^26,27,28 Although pediatric vitrectomy surgeries might not have similar endophthalmitis rates and it is not certain that each eye has independent endophthalmitis risk²⁹, it has been calculated that the risk for bilateral endophthalmitis after ISBVS would be 1 case in 150,000 to 1,000,000.¹³ This rate is much lower than the general anesthesia-related mortality rate in the pediatric population. To reduce the risk of bilateral endophthalmitis, we treated each eye as a new patient, as described in the methods.^11,13 None of our patients had endophthalmitis.

The mortality rate for pediatric patients subjected to general anesthesia ranges between 0.2 and 12.8 per 10,000.^21,30 It is estimated that simultaneous bilateral surgery reduces anesthesia-related complications by 50% for sequential surgery, especially in high-risk patients such as premature infants.²⁰ For preterm neonates, the risks of general anesthesia, such as intracranial hemorrhage, hypoxia, oxygen toxicity, postoperative apnea, bradycardia, and hypothermia, are greater than for term infants.22 Subjecting the infant to this risk for a second time in a short period might increase the risk of anesthesia-related complications. Besides, deterioration of the infant’s general status after the first surgery may delay the surgery of the contralateral eye. None of our patients had serious complications related to general anesthesia.

We performed ISBVS when both eyes had active stage 4 and 5 ROP disease, and delaying a second surgery would lead to disease progression in the latter eye. Most of these bilateral surgeries were done on stage 4A ROP because of the relatively short surgical time and less general anesthesia time. This complies with a previous international multicenter study, which suggests performing ISBVS for patients in whom the surgical intervention would be relatively short.¹³

Shah et al.¹¹ reported favorable results in their cases of simultaneous bilateral surgeries only in stage 4A ROP. Although most of our cases were also stage 4, we had 6 eyes with stage 5 ROP in our series, though the fellow eyes were stage 4 in all of these cases. Additionally, all of the stage 5 eyes were recent stage 5 cases who had been lasered before, which fixed the peripheral retina and prevented anterior closed-funnel retinal detachment.

Our results imply that preoperative plus disease is a good predictor of postoperative vitreous hemorrhage. PHD could be easily achieved in almost half of the eyes (48.6%) in the present series, contrary to the usual expectations in pediatric eyes. The anatomical success rate in our cases was 95.7% for stage 4A, 83.3% for stage 4B, and 50% for stage 5 eyes, similar to previous reports.^{11,12,14,31,32,33}

A large international multicentric retrospective study on ISBVS for pediatric retinal disorders reported ISBVS to be a feasible and safe treatment paradigm for pediatric patients with bilateral vitreoretinal pathological features when repeated general anesthesia is undesirable or impractical.¹³ These findings are supported by another recent study from India.¹⁶

Conclusion

In conclusion, as ROP is usually a rapidly progressive disease when untreated during the active stage, ISBVS should be considered in bilateral cases when there is a risk of rapid progression in both eyes and when comorbidities of the infant make a second general anesthesia undesirable. All precautions should be taken to reduce the risk of endophthalmitis. The risk of endophthalmitis should be weighed over the risk of anesthesia-related complications and disease progression.