To compare pars plana vitrectomy (PPV) with combined PPV and scleral buckle (SB) for the repair of noncomplex primary rhegmatogenous retinal detachment (RRD).
Retrospective, nonrandomized, interventional case series.
We reviewed 181 consecutive cases of vitrectomy for primary RRD at 2 major medical centers in Israel. The follow-up was at least 3 months. There were 96 eyes in the PPV group and 85 eyes in the PPV plus SB group. Main outcome measures were single-surgery anatomic success (SSAS) and final visual acuity (VA).
SSAS was achieved in 81.3% and 87.1% in the PPV and PPV plus SB groups, respectively ( P = .29). Final anatomic success rate was 98.9% and 98.8%, respectively ( P = .61). Final VA was 0.41 (20/51) in the PPV group and 0.53 (20/68) in the PPV plus SB group ( P = .13). The final VA was significantly better than the preoperative VA in both groups ( P < .0001). In detachments caused by inferior tears, SSAS rates were 80.9% and 81.5% in the PPV and PPV plus SB groups, respectively ( P = .74). In phakic eyes, SSAS rates were 92% and 87.5%, respectively, and in pseudophakic eyes, SSAS rates were 77.5% and 86.7%, respectively, in the PPV and PPV plus SB groups ( P = .29).
The reattachment rate and the final VA were similar in both groups. The addition of SB did not improve the results and was associated with slightly lower VA than with PPV alone. Tear location or lens status had no significant effect on success rates. It is likely that in eyes undergoing PPV for primary RRD, addition of a SB is not warranted.
Different surgical methods are available for the treatment of rhegmatogenous retinal detachment (RRD), including pneumatic retinopexy, scleral buckling (SB), and pars plana vitrectomy (PPV). High anatomic (retinal reattachment) and functional success rates are achieved with all methods in properly selected cases. Review of the recent literature indicates a shift toward the use of PPV instead of SB in certain RRD cases. A related controversy is whether to add an encircling buckle after vitrectomy is chosen as the primary procedure for RRD. In this retrospective study, we investigated the anatomic and functional results of PPV and PPV plus SB performed over a 6-year period for RRD in 2 large retina services in Israel. We also tried to identify prognostic factors for primary success in both surgical techniques, the causes for failure, and the final outcomes.
The charts of patients who underwent PPV for RRD in 2 public medical centers in Israel (The Sheba Medical Center and the Tel Aviv Medical Center) were reviewed retrospectively. The review period extended from January 1, 2004, through December 31, 2009. Inclusion criteria were primary RRD, PPV as the primary procedure (with or without SB), and a follow-up period of at least 3 months. Exclusion criteria were repair of RRD by SB or pneumatic retinopexy alone, any previous vitreoretinal surgery, any other previous ocular surgery except cataract extraction, proliferative vitreoretinopathy (PVR) grade C or worse, traumatic RD, traction RD resulting from proliferative diabetic retinopathy or other retinal conditions, RD related to retinopathy of prematurity, RD in children younger than 16 years, use of silicone oil in the first surgery, and giant tears. Because this was a retrospective study, there were no guidelines for the choice of the surgical approach, and the choice of whether to perform PPV or PPV plus SB was left to the surgeon’s preferences. The operations were performed by 5 vitreoretinal surgeons (A.B.,J.M. and three independent surgeons).
The data retrieved from the charts included: age, gender, laterality, duration of symptoms, hospitalization period, axial length, pre-existing diabetes mellitus and glaucoma, preoperative clinical examinations, intraoperative data and data from all follow-up examinations, additional surgeries needed, and complications. The patients were divided into 2 groups: patients who underwent only PPV and patients who underwent a combined PPV plus SB procedure.
Visual acuity (VA) was measured in all eyes on Snellen charts and was converted to the logarithm of the minimal angle of resolution. Very low VAs, such as counting fingers, hand movements, light perception, and no light perception, were substituted by logarithm of the minimal angle of resolution values of 1.7, 2.0, 2.5, and 3.0, respectively. The extent of the detachment was marked in clock hours. Number and location of breaks and involvement of the macula also were noted. Retinal breaks were defined as inferior if located between 4 and 8 o’clock. All other breaks were defined as superior.
Primary failure was defined as redetachment observed within 8 weeks from the surgical procedure, and late failure was defined as redetachment occurring after 8 weeks. Single-surgery anatomic success (SSAS) was defined as reattachment of the retina with 1 surgical procedure, not requiring any additional retinal procedures until the end of the follow-up period.
All patients underwent a standard 3-port 20-gauge PPV using a noncontact wide-angle viewing system combined with an image inverter (BIOM; Oculus, Lynnwood, Washington, USA). Perfluorodecalin (ARCAD Ophta; ARCALINE, Toulouse, France) was used to reattach the retina in all eyes. Endolaser photocoagulation was applied around the retinal breaks and 360 degrees at the periphery. In all cases, a nonexpansible concentration of perfluoropropane in air (12% to 16%) was used for tamponade. The buckling element in the PPV plus SB group was a 360-degree encircling band (no. 41 or no. 42 band; Labtician Ophthalmics, Oakville, Ontario, Canada). The anesthesia was either general or local (retrobulbar or sub-Tenon) with intravenous sedation.
Comparison between the 2 groups of patients regarding demographic and clinical data was carried out using the 2-sample t test for continuous variables, the Mann–Whitney nonparametric test for order-scale variables, and the chi-square test for categorical variables. Postoperative VA was compared with preoperative VA using the paired t test. A 2-way analysis of variance was performed to examine the effect of the type of surgery and lens status on the final VA. The interaction of the 2 parameters also was included in the analysis. Multivariate models were applied to the data to study the independent association of all demographic and clinical variables on surgical outcomes. Logistic regression was used for the need of added operation, and linear regression was performed for the final VA. Several model-building techniques were used to arrive at the best model: forced entry, forward selection, and backward elimination. SAS software for Windows version 9.1.3 (SAS Institute, Cary, North Carolina, USA) was used for all statistical analysis.
One hundred eighty-one eyes were included in the study series. The PPV group included 96 eyes, and the PPV plus SB group included 85 eyes. The average follow-up period was 12.8 ± 11.2 months in the PPV group and 11.7 ± 8.9 months in the PPV plus SB group ( P = .51).
Preoperative characteristics are summarized in Table 1 . The only difference between the 2 groups was a higher rate of pseudophakic eyes in the PPV group ( P = .003). No tear was found in 11 eyes (11.5%) and 17 eyes (20%) in the PPV and PPV plus SB groups, respectively. One tear was found in 47 patients (48.9%) and 44 patients (51.8%), and 2 or more tears were found in 38 patients (40.0%) and 24 patients (28.2%), respectively. These differences were not statistically significant. The intraoperative data are summarized in Table 2 . General anesthesia was used more frequently in the PPV plus SB group ( P < .0001). The duration of the operation was measured from conjunctival peritomy to closure of the last conjunctival suture, not including the anesthesia-related time. The average duration was 16 minutes longer in the PPV plus SB group ( P = .0009). Concurrent cataract extraction was performed in a small number of patients (9 patients, 5.0%).
|PPV plus SB Group (n = 85)||PPV Group (n = 96)||P Value|
|Average age (y)||60.3||62.1||.30|
|Right eye (%)||50.6||50.0||.93|
|Diabetes mellitus (%)||9.4||9.4||.79|
|Axial length a||25.8||25.0||.056|
|Intraocular pressure (mm Hg)||13.9||13.3||.41|
|Vitreous hemorrhage (%)||14.1||11.5||.59|
|Durations of symptoms (%)|
|1 day or fewer||11.8||20.8||.11|
|1 to 2 days||15.3||22.9|
|3 to 7 days||38.8||25.0|
|1 week or more||34.1||31.3|
|LogMAR visual acuity (Snellen)||1.07 (20/234)||0.96 (20/182)||.40|
|Macula on (%)||34.1||43.8||.36|
|Average no. of breaks||1.3||1.6||.10|
|Tear not seen (%)||20.0||11.5||.27|
|Average clock hours detached||5.0||5.4||.99|
|Detachment d/t superior tears||61.2||71.9||.29|
|PPV plus SB Group (n = 85)||PPV Group (n = 96)||P Value|
|Duration of operation (min)||92.2||76.2||.0009|
|Laser 360 degrees (%)||100||100||—|
|Gas tamponade (%)||100||100||—|
|Cataract surgery (%)||4.7||5.2||.88|
|Retina fully attached at operation (%)||97.7||97.9||.90|
Full attachment of the retina during surgery was achieved in all but 2 patients in each group. In the PPV group, 1 patient had a small persistent localized area of detachment around the inferior arcade. The other patient had a persistent localized RD, and 2 days later, a second operation was performed and the retina was fully attached. In the PPV plus SB group, 1 patient had a persistent small anterior detachment with laser applications surrounding it. The second patient had a small posterior retinal cyst and the surgeon decided not to drain it. The cyst resolved during follow-up.
Visual Acuity Results
The mean preoperative VA was 0.96 (20/182) and 1.07 (20/234) in the PPV and PPV plus SB groups, respectively ( P = .42). In both groups, the final VA was significantly better than the preoperative VA ( P < .0001 in both groups). The mean final VA was slightly better in the PPV group: 0.41 (20/51) compared with 0.53 (20/68) in the PPV plus SB group, but the difference did not reach statistical significance ( P = .13). The VA results were divided into 3 categories (so the functional outcomes are more easily interpreted) and are shown in Table 3 .
|PPV plus SB Group (n = 85)||PPV Group (n = 96)|
|20/40 or better||27 (32%)||33 (34%)|
|20/50 to > 20/200||15 (18%)||25 (26%)|
|20/200 or worse||43 (50%)||38 (40%)|
|20/40 or better||40 (47%)||60 (62.5%)|
|20/50 to > 20/200||30 (35%)||24 (25%)|
|20/200 or worse||15 (18%)||12 (12.5%)|
SSAS was achieved in 78 of 96 eyes (81.3%) in the PPV group and in 74 of 85 eyes (87.1%) in the PPV plus SB group ( P = .29). The rates of primary surgical failure (12.5% [12/96] and 9.4% [8/85] in the PPV and PPV plus SB groups, respectively) and late surgical failure (6.2% [6/96] and 3.5% [3/85], respectively) were similar. Overall, 152 (84%) of 181 eyes remained attached after a single procedure. In the 29 eyes (in both groups) that required additional retinal attachment surgery, PVR was responsible for 17 cases (58.6%), reopening of the original tear or a new tear were responsible for 7 cases (24.1%), and 1 redetachment was related to a direct ocular trauma. In the other 4 eyes, a specific cause could not be identified from the charts. The 29 eyes with redetachment required, overall, 38 additional surgeries to reattach the retina. In most cases (23/29), a single additional operation was sufficient, and only 2 eyes required more than 2 additional procedures. Most of the additional procedures included silicone oil injection with or without SB (34/38). In 6 eyes, the silicone oil was not removed until end of follow-up. Final anatomic success was achieved in 179 (98.9%) of 181 eyes: 95 (98.9%) of 96 eyes in the PPV group and 84 (98.8%) of 85 eyes in the PPV plus SB group.
Cataract surgery was performed during primary retinal reattachment surgery in 5 eyes in the PPV group and in 4 eyes in the PPV plus SB group. In the PPV group, progression of cataract was noted during the follow-up in 17 (85%) of 20 phakic eyes, and cataract surgery was performed in 10 eyes. In the PPV plus SB group, progression of cataract was noted in 33 (91.2%) of 36 phakic eyes, and cataract surgery was performed in 20 eyes. There was no statistical difference between the groups regarding cataract progression ( P = .59). Overall during the follow-up period, cataract surgery was performed in 60% of eyes that remained phakic after the primary retinal reattachment surgery.
Additional Nonretinal Reattachment Surgeries and Complications
Fifteen additional procedures for complications other than cataract were performed in 7 PPV eyes and 8 PPV plus SB eyes, including epiretinal membrane peeling (4 in each group), intraocular lens repositioning (2 in each group), removal of a perfluorocarbon bubble (1 in each group), scraping of band keratopathy in 1 patient, and band removal in another patient. Postoperative glaucoma was documented in 10 eyes, 2 in the PPV group and 8 in the PPV plus SB group ( P = .03). Pseudophakic bullous keratopathy developed in 5 eyes, 2 in the PPV group and 3 in the PPV plus SB group.
Lens Status and Outcome
Overall, pseudophakic patients underwent significantly more PPV without SB compared with phakic patients ( P = .003). The SSAS rate was 89.2% (58/65) and 81% (94/116) in the phakic and pseudophakic patients, respectively ( P = .15). In the PPV group, the SSAS rate was 92% (23/25) and 77.5% (55/71) in the phakic and pseudophakic patients, respectively ( P = .11). In the PPV plus SB group, it was 87.5% (35/40) and 86.7% (39/45), respectively ( P = .91). The mean final VAs in the phakic and pseudophakic groups were 0.48 (20/60) and 0.46 (20/58), respectively, and the difference was not significant ( P = .81). In the PPV group, mean final VA was 0.41 (20/51) and 0.42 (20/53) in the phakic and pseudophakic groups, respectively. In the PPV plus SB group, mean final VA was 0.52 and 0.53 in the phakic and pseudophakic groups, respectively.
Tear Location and Outcome
There was no difference regarding tear location in both groups. In 121 (66.8%) eyes (69 and 52 in PPV and PPV plus SB groups, respectively), superior retinal tears were found, and in 48 (26.5%) eyes (21 and 27 in PPV and PPV plus SB groups, respectively), inferior tears were found ( P = .29). In 12 (6.6%) eyes, 6 in each group, a tear was not found, and SSAS was achieved in 10 (83.3%) of these 12 eyes. In 2 cases, a single additional surgery was performed because of primary surgical failure. In all cases of retinal detachments resulting from an unknown tear, the retina was attached at the end of follow-up. Tear location did not determine the rate of SSAS, which was 85.1% (103/121), 81.2% (39/48), and 83.3% (10/12) for the superior, inferior, and undetectable tear groups, respectively ( P = .74).
A multivariant analysis was carried out for all preoperative and intraoperative data. These included age, gender, diabetes mellitus, glaucoma, duration of symptoms, preoperative VA, presence of vitreous hemorrhage, lens status, number of tears, size of detachment in clock hours, detachment resulting from superior or inferior tears, macular status (on or off), and type of surgery (PPV vs PPV plus SB). We evaluated these parameters against 2 outcomes: SSAS rate and final VA. The only parameter that correlated with final VA was the preoperative VA. None of the other mentioned parameters was correlated with the final VA or SSAS rate.