Indications and Outcomes of Patients Undergoing Immediate Sequential Bilateral Vitreoretinal Surgery: A Case Series Open Access

A patient presenting with bilateral sight threatening vitreoretinal disease requiring urgent treatment is a challenging but not uncommon scenario for a vitreoretinal surgeon. Common practice has been to address either eye in separate, staged procedures. Operating on both eyes in the same anaesthetic sitting known as immediate sequential bilateral vitreoretinal surgery (ISBVS) has become more widely accepted in the treatment of paediatric patients [1]. However, in adults there have only been a small number of cases series describing this approach in adults [2, 3]. We report the indications and clinical course of a retrospective cohort of patients undergoing ISBVS and discuss the relative merits.

The study was conducted in a multicentre retrospective case series of patients undergoing ISBVS. Cases were identified by invitation in two professional vitreoretinal forums to colleagues from across the UK. Cases reported elsewhere were not accepted. A standardised proforma was used to contribute cases to the series.

All surgeries were performed by experienced vitreoretinal surgeons in National Health Service (NHS) hospitals in the UK. All cases in this series were performed with tight adherence to hospital safety protocols and were subject to clinical governance. Choice of surgical approach was that of the operating surgeon. Strict aseptic segregation of cases was deployed following guidelines described by the Royal College of Ophthalmologists for bilateral cataract surgery, namely, re-scrubbing between cases, separate instrumentation and different batches of devices and drugs [4].

Data collected included demographics, pre-operative vision, indication for surgery, rationale for bilateral approach, operative details, post-operative vision, and complications. Vision was considered to have improved or deteriorated if there was a change of two lines or more.

A total of 128 surgeons were contacted for cases; 11 surgeons responded. Two cases were excluded as one had been reported elsewhere and no proforma was supplied for the second. Nine surgeons from eight centres contributed a total of 17 patients (34 eyes) undergoing ISBVS (Table 1). Age of the patients ranged from 18 to 72 years, 8 patients were female. Pre-operative vision was 6/60 or worse bilaterally in 9 patients and in 20 eyes in total.

Indications for surgery in 10 cases were due to bilateral rhegmatogenous retinal detachments (RRDs), five due to proliferative diabetic retinopathy, one vitreous haemorrhage and one full thickness macular hole (FTMH). The indication was the same in both eyes in each case. Avoiding delay to treatment was the most frequently cited reason for ISBVS (9/17), concern regarding general anaesthetic risk was second most (3/14). One case combined scleral buckle in one eye with vitrectomy in the fellow eye, 3 cases had bilateral buckles and 1 case had bilateral phaco-vitrectomies. Regarding choice of internal tamponade, air was used in eleven eyes, silicone oil was used in just one eye with no tamponade required in the fellow eye, and just 1 case used long-acting gas in both eyes.

Post-operative vision improved in 22 eyes, remained the same in ten and worsened in two. Four patients (six eyes) experienced post-operative complications. Reported vision was that acquired in the usual post-operative period and, therefore, is spectacle corrected rather than best corrected with clear lens if cataract had developed. One patient had post-operative high intraocular pressures, vitreous haemorrhage and cystoid macular oedema in one eye, and a vitreous haemorrhage in the fellow eye. One eye had vitreous haemorrhage, one eye had a macular fold, and 1 patient had ocular hypertension in both eyes. One patient required further surgery for non-clearing vitreous haemorrhage. There were no incidents of endophthalmitis.

Immediate sequential bilateral cataract surgery (ISBCS) is becoming common practice in the UK following recommendations issued by The Royal College of Ophthalmologists [4]. The national cataract audit demonstrated no increased risk of endophthalmitis if bilateral aseptic segregation protocols were respected.

We have presented 17 cases of ISBVS successfully completed from 8 centres from across the UK. We will explore in more detail the pre-operative, intra-operative, and post-operative considerations when performing ISBVS and make a case for when this should be considered.

Patients presenting with bilateral vision threatening disease requiring relatively urgent surgery is not an uncommon scenario. Patients presenting with RRDs have simultaneous detachments bilaterally 1–2.5% of the time, and this is more common in younger patients and those with multiple round holes [5‒7]. A staged delayed approach in treatment to each eye can risk progression of disease, while causing significant anxiety for patient and surgeon. A patient progressing from “macula-on” to “macula-off” or a significant delay in repairing “macula-off” RRDs can all lead to detrimental outcomes [8]. While the exact urgency and risks of delay continue to be debated, a delay of more than a few days is generally not acceptable except in chronic detachments [9]. The second most cited rationale was high anaesthetic risk, the risk of death is routinely quoted as 1:100,000 for routine general anaesthetic but is much higher depending on patient factors and there is no universally accepted method for quantifying this risk [10]. If a patient were to die during a second anaesthetic who was deemed high risk, this may lead to questioning of the rationale for separates staged procedures. These considerations of clinical urgency and risk are perhaps the most tangible to surgeons. “System pressures” such as shortage of overnight hospital beds or access to an anaesthesiologist were also listed as a relevant but not primary factor in several cases. Other reasons cited included difficulty for patients attending for multiple procedures and incumbent follow-up appointments, patients with learning difficulties or those with caring responsibilities. Patient choice was also an indication and in the practice of modern medicine a patient-centred approach is now advocated, and these factors must be given due consideration. Thus, there are compelling reasons to consider a bilateral simultaneous approach.

Choice of posturing and tamponade are of great relevance to ISBVS vitreoretinal surgery. In our series posturing was recommended for half of patients and no posturing for half. These decisions are more complex than when operating on one eye only and may be why it was only recommended in half of cases. A surgeon may wish to posture as appropriate for the most high-risk eye, or the eye with the shortest acting tamponade. In most of the cases air or a short acting tamponade such as SF6 was used. Use of bilateral long-acting tamponade was chosen by only one of our contributing surgeons (for bilateral full thickness macular hole). The considerable distress of extreme blurring of long-acting tamponades may be why this was rarely used in our series and why bilateral macular holes are not routinely treated simultaneously [11]. The nature and position of the retinal pathology will primarily dictate the choice of procedure and tamponade but this must be balanced against a patient’s visual needs, early recovery and regaining of independence. Choice of tamponade and posturing is also thought to be crucial in preventing macula folds and 1 patient in our series did develop a full thickness macula fold, but given the rate after RRD repair is approximately 2% a larger study is needed to investigate if ISBVS increases this risk [12]. Furthermore, the pre-operative plan for approach and tamponade can be challenged intra-operatively, and a surgeon may be compelled to choose a long-acting tamponade or oil that they had not planned to. This reflects some of the challenges of performing bilateral cases and a surgeon must be comfortable with the decision making of balancing post-operative recovery while maximising chance of success for an individual operation. This increased complexity and uncertainty may contribute to why ISBVS has been relatively rarely adopted.

In our series 22 eyes improved, ten were stable and two experienced a deterioration in vision of two lines or more. Although for those that had deterioration in vision, each had good pre-operative acuities and relatively small reductions in vision and, thus, cannot be simplistically interpreted as failures. Six eyes experienced complications, but just one requiring further surgery for persistent vitreous haemorrhage and there were no cases of endophthalmitis. The risk of complications is understandably a major objection to bilateral ocular surgery. However, bilateral simultaneous intravitreal injections have become standard practice and ISBCS has been growing in popularity with large multi-centre randomised control trials increasing the evidence of its safety [13]. Bilateral endophthalmitis was initially cited as the major objection to performing ISBCS but when bilateral aseptic segregation protocols have been followed there have been no registered cases of bilateral endophthalmitis; therefore, it has been postulated that the risk to each eye should be independently considered, although of course patient specific risk factors remain [4, 14]. The risk of endophthalmitis for vitreoretinal surgery is lower than for cataract surgery, approximately 0.05% as shown in meta-analysis [15]. However, intra-operative complications such as iatrogenic breaks and lens or retinal touch, suprachoroidal haemorrhage and post-operative complications such chronic cystoid macular oedema, chronic proliferative vitreoretinopathy retinal detachment and phthisis are all likely to be higher than in cataract surgery. Rates of reported complications vary widely but the National Ophthalmology Database study found for diabetic vitrectomy with delamination a 30% intra-operative complication rate, 15% needing further vitrectomy, 63% achieving visual improvement and 15% visual loss [16]. However, the risk of permanent vision loss from delayed retinal surgery compared to cataract surgery is also far greater, thus the harms vs. benefit analysis is very different from that of cataract and straight lines of comparison cannot be drawn as surgery is more urgent.

Given the dearth of published evidence we see two prerequisites to considering ISBVS, first, a thought experiment that both patient and surgeon are satisfied that if a staged approach was taken and the first eye developed a delayed vision threatening complication (such as endophthalmitis) one would still proceed to operate on the second eye [2, 3]. Secondly, the patient is at significant risk of life-threatening complications from anaesthetic or permanent vision loss from delayed surgery. If both criteria are satisfied a detailed discussion regarding ISBVS is justified. Where the first prerequisite is satisfied but not the second, and the patient wishes it also seems there is a case to be made for an immediate sequential approach.

ISBVS offers significant potential advantages in terms of reducing the risks from repeated anaesthetics, progression of disease due to delay and benefits for patients’ recovery and follow-up. This case series illustrates the feasibility of immediate sequential bilateral vitreoretinal surgery as a treatment option, but each case should be tailored to the situation at hand and discussed with the patient. Questions of risk are hard to address as only small numbers of published cases are available and we advocate further larger studies to better establish the safety of this technique to inform better patient care.

The research methods and analysis plan adhered to the tenets of the Declaration of Helsinki. NHS Health Research Authority was approached and this project was considered an Audit and no further ethics approval was required. Written informed consent was obtained for all patients included into the study.

The authors declare that they have no competing interests.

No funding received for this study.

A.I.S.: main manuscript writing, data acquisition. A.G.: manuscript writing, final review of the manuscript. S.W.: data acquisition, final review of the manuscript. G.M.: data acquisition, final review of the manuscript. S.B.: data acquisition, final review of the manuscript. C.M.R.: data acquisition, final review of the manuscript. A.C.: data acquisition, final review of the manuscript. J.K.: data acquisition, final review of the manuscript. A.D.: data acquisition, final review of the manuscript. R.H.: data acquisition, final review of the manuscript. D.H.S.: data acquisition, final review of the manuscript. S.S.: project conceptualisation, manuscript writing, final review of the manuscript. All authors read and approved the final manuscript.

The data that support the findings of this study are not publicly available due their containing information that could compromise the privacy of research participants but are available from the corresponding author upon reasonable request.