Elsevier

Survey of Ophthalmology

Volume 63, Issue 4, July–August 2018, Pages 579-588
Survey of Ophthalmology

Diagnostic and surgical techniques
Clinically undetected retinal breaks causing retinal detachment: A review of options for management

https://doi.org/10.1016/j.survophthal.2017.08.002Get rights and content

Abstract

The successful detection of retinal breaks is a critical step in rhegmatogenous retinal detachment surgery in order to prevent persistent/recurrent retinal detachments. Not all retinal breaks causing retinal detachments are obvious. Retinal breaks may be obscured by opacities that are either anterior segment related, lens related, or posterior segment related. Rules to identify breaks based on subretinal fluid configuration are more difficult to apply in pseudophakic, aphakic, and scleral buckle encircled eyes—and in eyes with repeat detachments and those with proliferative vitreoretinopathy. Exudative detachments exhibit characteristic features and must be ruled out. A thorough clinical examination preoperatively is important even if a vitrectomy is planned. We review the incidence and causes of undetected breaks, along with preoperative/clinical issues that may hinder break detection. We review the literature with respect to investigative approaches and techniques that are available to the vitreoretinal surgeon when primary breaks remain clinically undetected during the preoperative examination. We broadly divide the surgical approaches into ones where the surgeon utilizes techniques to pursue actively a search for breaks versus adopting a purely speculative approach. Advantages and disadvantages of various techniques are appraised. Intuitively one might argue that an encircling scleral buckle combined with vitrectomy would give higher single operation success than pars plana vitrectomy alone because “undetected” retinal breaks would be addressed by a 360° plombage. We could not confirm this concept. Newer techniques, such as pars plana vitrectomy augmented with dye extrusion or endoscopic-assisted pars plana vitrectomy, show encouraging results. Technological advances such as intraoperative optical coherence tomography will also help to broaden the vitreoretinal surgeon's armamentarium. At this time, there is no gold standard in terms of the recommended approach, and this is reflected in the many options that are available for management. The surgeon must consider the benefits versus the risk of their preferred approach.

Introduction

Identification of retinal breaks is an important aspect of rhegmatogenous retinal detachment (RRD) repair. An unsealed break will allow transretinal fluid flow into the subretinal space and cause a redetachment. Despite a thorough preoperative search, retinal breaks in a thin, optically translucent retina may remain elusive. We consider the incidence and causes of undetected breaks along with preoperative/clinical issues that may hinder break detection. We review the management strategies and techniques that have been described in the literature to identify and manage clinically undetected breaks. We discuss their results and appraise their advantages and disadvantages. Future tools and directions are reviewed. This assumes that a thorough preoperative examination was unsuccessful in determining the location of a primary break.

Broadly speaking, the management of clinically undetected breaks can be divided into a surgical approach where the surgeon employs techniques that are aimed at break detection, versus a management strategy that is speculative, where the intention is not to determine the location of the break.

Where the intention of the surgeon is to find the break, the preoperative search can be performed externally or internally. External approaches are cryotherapy-based interventions. Internal approaches can be gas-assisted interventions (largely of historical interest) or vitrectomy-based interventions. In contrast, with the speculative approach the aim is not to seek a break operatively, but to apply a buckle to the area the break is likely to be found. Only a postoperative successful reattachment confirms that the primary break was adequately treated.

The techniques are individually discussed, and their advantages and disadvantages appraised. A descriptive approach is taken in the analysis of the published studies. As different studies employed different outcome measures, direct comparisons are not possible. All published methods pertaining to undetected breaks found in our literature search are discussed. Some options are of historical interest, but have been included for the sake of completeness. Table 1 summarizes the techniques and study findings.

External approaches are cryotherapy-based interventions involving 1) changes in retinal opacity and/or 2) schlieren.

Griffith and colleagues 12 described the use of cryotherapy in the search for retinal breaks. They noted that the small breaks could be temporarily rendered opaque as they were being engulfed by the cryotherapy-induced ice ball. This was termed as the “immediate cryotherapy test.” Additionally, they noted that the break was seen more clearly a few minutes later as the retina developed a light gray change (“delayed cryotherapy test”). In effect the break is rendered visible owing to the contrast with the freeze-induced opaque retina surrounding the break. Cryotherapy in 2 confluent rows was applied between the ora and equator in the region of the suspected area. This was followed by drainage of subretinal fluid (SRF) and scleral buckling (SB) anterior to the equator. They reported their technique in a case series of 41 eyes with no apparent break. Cure was defined as reattachment for 6 months and was achieved in 91% of cases where there were no cases of proliferative vitreoretinopathy (PVR).

Schlieren phenomenon is defined as optical inhomogeneities in transparent media and may be observed with kinetic indentation during binocular examination (see Clinical detection section). Additionally, with the cryotherapy approach previously mentioned, it may be possible to see pigment dispersed into the SRF from the retinal pigment epithelium (RPE) as a plume through the break. We discuss the concept of schlieren in more detail later in the context of heavy liquids in the following section.

Internal approaches can be divided into 1) gas-assisted interventions and 2) pars plana vitrectomy (PPV)-based interventions. These are further subdivided into: 1) indentation, 2) schlieren, with and without heavy fluids and/or silicone, 3) subretinal dyes, 4) PPV combined with SB, and 5) PPV assisted with endoscopy.

Lincoff and colleagues21 describe a technique using an expanding bubble of intraocular gas (xenon). After expansion of an appropriate expansile volume of gas, the eye is serially monitored over the next few days as the expanding bubble flattens the retina. Once the expanding gas bubble reaches the level of the clinically undetected break and seals it, the retina inferior to the bubble flattens due to resorption of SRF by the RPE pump. The same principle can be applied in reverse as the bubble resorbs, but the SRF needs to be drained first. This technique can be applied in the setting of multiple breaks, in which case once the expanding bubble seals the superior break, the level of SRF should drop to that of the next lower-down break. The authors describe the successful use of the technique in a case series of 5 patients. Possible problems with this technique include situations where there is delayed resorption of SRF making it difficult to determine the level of the break, though this is unlikely. Second, they point out that a bubble could displace superior fluid and make an inferior detachment more bullous. Once again, they point out that this is unlikely as the expansion is slow, and SRF will probably return to the vitreous compartment until the break is tamponaded.

An internal search for retinal breaks using indentation microsurgery was first described by Rosen et al.31 The technique encourages visualization of breaks near the ora serrata. Deep kinetic indentation of the sclera combined with endoillumination enabled breaks that were thought to be the cause of the retinal detachment (RD) to be identified during closed microsurgery in 95% (74/78) of cases. In 52 cases, the breaks were preequatorial. There was a preponderance of breaks in the superior hemisphere. In those eyes with previous SB (48 cases), newly discovered breaks were posterior to the buckle in 20 cases (42%), anterior in 9 cases (19%), on the buckle in 2 cases (<1%), and bore no relation to the explant in the remainder (20%). Retinal reattachment was eventually achieved in 85%.

Heavy liquids alone can be used to vent SRF out of a break. The surgeon relies on the difference between the refractive indices of the proteinaceous SRF versus the vitreous infusate. The optical inhomogeneity in transparent media, visualized as a distortion in the form of a “streak” or “plume” is termed “schlieren.”9 The observation of schlieren during vitrectomy therefore suggests the presence of SRF and a retinal break not already diagnosed. It is argued that the success rate with this technique may be relatively low due to the likely small size of the undetected breaks and the small volume of SRF streaming out through the break.14, 23

Brazitikos and colleagues3 describe the use of schlieren in a case series in the setting of pseudophakic RD with no breaks diagnosed preoperatively (14 patients). PPV was the primary means of repair, but SB was used in cases where there was significant vitreous inflammation (2 cases), an iatrogenic sclerotomy site break (1 case), in the presence of subretinal strands (1 case) and in one instance where the break was not found. Perfluoro-n-octane (PFO [C39F41]) was used as an intraocular tool, principally for retinal flattening. Most schlieren were detected without the use of PFO. The final attachment rate was 100%.

Martinez-Castillo and colleagues23 describe a stepwise escalating approach in cases where a primary break could not be identified preoperatively. Starting with dynamic scleral indentation, peripheral vitrectomy, and diffuse illumination, break detection was attempted by the application of Lincoff's rules.20 After this, PFO was injected to promote the schlieren effect. This was only effective in 11 of 25 eyes. The low detection rate was attributed to the small size of the retinal breaks and the small amount of SRF streaming out through the breaks. Failure of this was followed by meticulous peripheral dissection of the peripheral vitreous after injection of PFO and triamcinolone acetonide, with dynamic scleral indentation. The aim was to allow drainage of SRF through the break and facilitate Schlieren. When no retinal break could be identified with the vitreous cavity filled with PFO or air, then circumferential retinopexy was performed using a diode laser, and the vitreous cavity was filled with silicone oil. Otherwise, balanced salt solution was left in the vitreous cavity. With this approach, retinal breaks were found intraoperatively in 60 eyes (98%). In 25 of 61 study eyes (41%), best-corrected visual acuity was 20/40 or better. Primary retinal reattachment was attained in 60 study eyes (98%). Final reattachment was achieved in all 61 eyes.

The principle of direct internal search with schlieren phenomenon has been modified using dyes to increase contrast between plumes of dye against the vitreous infusate. This is achieved by preplacing a dye in the subretinal space. These are extrusion techniques,13, 16, 40 involving injection trypan blue (TB) (Membrane Blue, DORC, and NI) into the SRF. Extrusion of the dye is encouraged through the clinically undetected break using perfluorocarbon liquid to fill the eye and systematic rotation of the globe, with the aim of seeing a plume of dye venting out of the break. The use of a dye provides color contrast that aids detection and is an advantage over the use of heavy liquid alone. In some instances, the dye stains the devitalized tissue of the break itself. The techniques are reported in the context of both primary and repeat RD repair during vitreous surgery. Two approaches of preplacing dye into the subretinal space are described: transretinal16, 40 and transscleral.13

The transretinal injection technique was employed after standard scleral indention failed to reveal any break.16, 40 TB was injected in the postequatorial subretinal space using either a 41-G needle or through a posterior retinotomy using a 20-G soft-tipped cannula. Perfluorocarbon liquid was injected over the retinotomy and displaced the TB anteriorly. Breaks were identified by searching for extrusion of dye, encouraged by indentation, from sites other than the retinotomy. This technique could also be used to trap the dye in suspected areas in order to exclude a break at a given location. Dye was removed through the retinotomy site. Breaks were found in 89% of eyes (42/47), and 81% underwent only local retinopexy and gas tamponade. Overall anatomical success rate was 76%, with a success rate of 83% in primary RD repair and 74% in repeat surgery. Eighteen of 47 had PVR graded C2 or worse. Interestingly, with respect to the distribution of occult breaks, 29/47 were in the previously untreated retina, 7/47 at the edge of previous retinopexy sites, 3/47 were leaks at the anterior vitreous base, and 2 were peripapillary breaks.

A transscleral approach has also been described in the context of recurrent/persistent RD in vitrectomized eyes.13 In a retrospective, consecutive, single-surgeon case series, patients presenting with a repeat RRD after having been treated with PPV as the method of primary RRD repair, transscleral injection of subretinal vision blue was used to help identify retinal breaks during repeat vitrectomy. With this technique, vision blue was injected transsclerally using a 30-G needle mounted on a 1-ml syringe and the needle tip placed against the globe like an indenter, bevel orientated away from the sclera. Dye was injected into the most bullous portion of the RD. Dynamic scleral depression using an indenter with endoillumination was performed to encourage the dye to vent out of the undetected break. When successful, a plume of dye was visible in the vitreous infusate. If no plume was seen, then heavy oil (perfluorodecalin) could be used, in conjunction with globe rotation, to encourage expression of dye. Once it was determined that there were no other breaks, the dye was drained through the break site. A drainage retinotomy was required on one occasion where no break was identified. Cryotherapy was applied to the newly found break.

The transscleral injection of subretinal vision blue technique was used in 8 instances in 7 eyes. All 8 instances were repeat RDs. Transscleral injection of subretinal vision blue facilitated occult break detection in 7/8 instances of use. Breaks were at or adjacent to the previous cryo site in 3 cases. Persistent retinal attachment was achieved in 5/7 cases. Final visual acuity increased in 5/7 cases. Possible complications inherent with this technique include choroidal hemorrhage and hypotony, though none were reported.

Studies that are presented in this section are those where the authors' choice of approach was to combine SB with PPV at the outset. These are by Wong and colleagues39 and Desai and Strassman.7 Studies that employed SB alone (or compared SB with SB + PPV) are reviewed separately in the speculative approach section.

Wong and colleagues39 describe a series of 47 patients with combined PPV and SB (20-G PPV, peeling of preretinal membranes if present, SB, cryotherapy, and internal tamponade) for RRD with unseen retinal holes. They reported no statistical difference in the incidence of finding holes between cases with a good view (10/25 cases) and poor view (8/22 cases). There was a statistically significant difference in the location of the holes in cases with a good view (all 10 in the preequatorial retina) and those with a poor view (4 located preequatorially and 4 posteriorly). In the 29 cases where the hole was not detected, the retina was attached in 16 cases (52%). Of the 18 cases where the break was undetected preoperatively, the retina was attached in 12 (67%). It was noted that PPV did not guarantee break detection (holes not found in 29/47). Where the preoperative view is poor due to media opacities, holes were not found in 14/22 cases. The main advantage of PPV was the removal of media opacities that enabled the detection of posterior breaks that would not have been supported by equatorial encirclement. When the preoperative view was good and PVR graded C1 or C2, patients receiving vitrectomy in 12/16 (75%) and conventional RD encirclement surgery 12/17 (70.5%) achieved successful reattachment, demonstrating no significant difference between the 2 approaches.

Desai and Strassman7 describe PPV, fluid-air exchange, internal drainage, and endolaser together with SB for pseudophakic or aphakic patients with an RD with an unseen break in 10 patients. At 6-month follow-up, all patients maintained an attached retina after 1 operation.

More recently, direct endoscopic visualization to find undetected retinal breaks in the context of pseudophakic and aphakic RDs has been described.18 This technique involved a 20-G 3-port PPV using a fiberoptic endoscope as a light source. Under endoscopic control, shaving of the vitreous base and detection of retinal breaks were performed without scleral indentation. Breaks were treated with transscleral cryopexy or with laser endophotocoagulation under endoscopic visualization. In 19/20 eyes, breaks were identified and retina reattached after single surgery in all cases. The case in which the break could not be visualized was one of high myopia with chorioretinal atrophy and a tessellated fundus. Here, indentation did not help either, and SB was used. SB was used in 7 additional cases (3 due to vitreous inflammation and 4 due to younger age). There were no serious complications related to the technique.

SB (segmental or encircling) can also be used for dealing with unidentified breaks during primary repair. As such, these are not methods aimed at detection of an unidentified break, but rather areas are treated so as to cover the likely region in which a break exists, based on the configuration of the RD, since the primary break is localized there 95% of the time.33

“Prospective segmental buckling,”31 also termed “speculative,”29 is where SB is applied to only to the area of probability of the break location. Applying Lincoff's rules,20 for superior temporal or nasal RD, the upper 1.5 hours are buckled; for a superior RD crossing the 12 o'clock radian, 1.5 hours either side 12 o'clock are buckled. With an inferior RD, up to 3 hours beneath the higher border of RD to 6 o'clock. Interrupted laser applied over the entire length of the prospective segmental buckle to secure any undetected breaks on it. Failure of attachment suggests that the area buckled probably does not contain the break or all of the breaks. Lincoff and Kreissig21 describe rules for managing such breaks.

Studies that are discussed here are those in which the initial intended definitive management was with SB (Salicone and colleagues32; Tewari and colleagues35; Crick and Chignell6; Wu and colleagues42; and Kocaoglan and colleagues19); 2 of these studies had a comparison group (Salicone32 and Tewari35) of SB +PPV; and these studies are discussed here instead of the following section (combined approach). Wu and and colleagues42 and Kocaoglan and colleagues19 used PPV as the secondary, follow-up, procedure in the event of unsuccessful reattachment.

Crick and Chignell6 describe a case series of 30 patients where breaks could not be identified. This series excluded cases in which cryotherapy during the operation revealed the break. The exact number of these was not stated. Thirteen eyes were encircled (8 of these were total RDs and 5 involved all quadrants and had no localizing signs), and 15 were drained, principally because of poor retinal mobility. Four cases (13%) failed, requiring repeat surgery, with 2 of these being successful. Of the 4 cases that failed, 3 were traumatic and 1 was a chronic RD over 6 months old. The authors go on to give examples of when radial buckles and encircling SB would be appropriate, concluding that “no-hole” RDs are best treated with encircling SB given that 60% of all RDs have more than 1 hole.

Kocaoglan and colleagues,19 treated 45 eyes without detectable breaks using an SB (360° 2.5-mm encircling silicone band) placed just anterior to the equator with one mattress suture in each quadrant. SRF was drained externally (hypotony in 16 cases was managed with air). Cryotherapy was applied to lattice and suspicious areas in 21 eyes. As the primary procedure, SB was successful in 28/45 eyes (62.2%). Re-operation was indicated in 17 eyes but only possible in 11 (due to patients being lost to follow-up or declining treatment). PPV was employed as the second procedure and successful in 6/11 eyes.

Wu and colleagues,42 describe SB (with cryotherapy) extending over the circumference of RD as the primary treatment in 25 cases of pseudophakic RD with anatomic success in 18 cases (72%). Uncomplicated recurrence of RRD was treated with PPV + internal SRF drainage and long-term tamponade, and the overall success rate was 92%.

Tewari and colleagues35 compared SB alone with PPV plus SB combined. Forty-four consecutive cases where the RDs were uncomplicated and ocular media were clear were included in the study and randomized into 2 groups for management. The SB group underwent 360° SB (7-mm grooved asymmetric silicone tire) with encirclement (2.5-mm silicone band), cryopexy to suspicious areas, and external SRF drainage (26-G needle). A primary reattachment rate of 70% (14/20 cases at 3 months) was achieved, with no statistical difference in the results between the isolated SB group and combined group (P = 0.716) and no statistically significant difference in the final visual acuity (P=0.4). The 6 eyes with failure resulted from open breaks with PVR in 3/6, advanced PVR in 2/6, and an open break in 1/6. These were found during subsequent PPV. In patients undergoing the combined approach, retinal holes in 11/20 (55%) were found during vitrectomy. Of the 4 patients that failed in this group, 3 had advanced PVR, and 1 had a break at the laser burn site. They concluded that, when there is a good preoperative view of the retina, PPV does not offer any additional benefits over SB, nor does the PPV guarantee localization of occult breaks. They noted that the complications (intraoperatively and postoperatively) were higher in the PPV group, with raised intraocular pressure, persistent epithelial defects, progression of cataracts, and cystoid macular edema.

Salicone and colleagues32 compared primary SB (360° with cryopexy to suspicious areas and external SRF drainage) with SB + PPV. They achieved a single operation success rate of 61.5% (16/26) in the SB group, versus 72% (13/18) in the combined approach, with no statistically significant difference between the 2 groups (P = 0.17 log-rank test). At the final visit, the retina was attached in 83.3% of cases managed with a combined approach and 84.6% managed with SB. Complication rates were similar in both groups but the PPV approach accelerated cataract formation.

Section snippets

First principles for finding the retinal break

The shape of the RD indicates the position of the primary break 96% of the time, as per Lincoff's rules.20 These rules divide primary breaks into superior or total, lateral (temporal or nasal), and inferior. The extension of SRF depends upon the position of the most superior break, the effect of gravity, and anatomical limits (the disc, the ora serrata, and any chorioretinal adhesions). Conversely, when a break is found, its location must be able to account for the configuration of the RD;

Conclusions

The goal of RD surgery is to optimize visual outcome, not solely to achieve retinal reattachment. Vitreoretinal surgeons will be aware that not all retinal breaks causing RDs are obvious. Retinal breaks may be undetected because of opacities that are either anterior segment related, lens related or posterior segment related. Rules to identify breaks based on SRF configuration are more difficult to apply in pseudophakic, aphakic, encircled eyes, and eyes with repeat detachments and those with

Disclosures

The authors report no proprietary or commercial interest in any product mentioned or concept discussed in this article.

References (42)

  • D.J. Bradford et al.

    Pseudophakic retinal detachments

    Retina

    (1989)
  • P.D. Brazitikos et al.

    Primary vitrectomy with perfluoro-n-octane use in the treatment of pseudophakic retinal detachment with undetected retinal breaks

    Retina

    (1999)
  • P.A. Campochiaro et al.

    Cryotherapy enhances intravitreal dispersion of viable retinal pigment epithelial cells

    Arch Ophthalmol

    (1985)
  • M.D. Crick et al.

    Treatment of rhegmatogenous detachment without apparent holes

    Trans Ophthalmol Soc U K

    (1977)
  • U. Desai et al.

    Combined pars plana vitrectomy and scleral buckling for pseudophakic and aphakic retinal detachments in which a break is not seen preoperatively

    Ophthalmic Surg Lasers

    (1997)
  • L. Gopal

    Locating the retinal break(s) in rhegmatogenous retinal detachment: the first step in successful management

    Indian J Ophthalmol

    (2001)
  • D. Gupta et al.

    Trans-scleral dye injection during vitreous surgery to identify clinically undetectable retinal breaks causing retinal detachment

    Eye

    (2011)
  • E.H. Jaccoma

    Cryotherapy causes extensive breakdown of the blood-retinal barrier

    Arch Ophthalmol

    (1985)
  • J.H. Kim et al.

    Modified external needle drainage of subretinal fluid in primary rhegmatogenous retinal detachment: a prospective, consecutive, interventional, single-surgeon study

    Retina

    (2007)
  • M. Kita et al.

    Endoscope-assisted vitrectomy in the management of pseudophakic and aphakic retinal detachments with undetected retinal breaks

    Retina

    (2011)
  • H. Kocaoglan et al.

    Management of rhegmatogenous retinal detachment without detectable breaks

    Clin Exp Ophthalmol

    (2002)
  • Cited by (0)

    Acknowledgement of any proprietary interests or research funding: Nil to declare.

    1

    These authors contributed equally.

    View full text