Pars plana vitrectomy (PPV) with gas tamponade is widely popular for the treatment of rhegmatogenous retinal detachment (RRD). Nonexpansile gases, such as 18% sulfur hexafluoride (SF6), 14% octafluoropropane (C3F8), and room air, are commonly used as gas tamponade at the end of vitrectomy [
Due to technical advances, the success rate of vitrectomy for RRD has soared; however, surgeons consider the success rate as well as patient compliance. Recently, a prospective study of inferior RRD by Zhou et al. [
Herein, we review our case results with room air tamponade and compare them with previous results using heterogeneous gas tamponade.
The current study was a retrospective, interventional, consecutive case series. The medical records of consecutive patients that underwent vitrectomy and gas tamponade for primary RRD between January 2013 and December 2015 were reviewed. We excluded cases treated by scleral buckling, vitrectomy combined with scleral buckling, or use of silicone oil tamponade. Patients who had a history of intraocular surgery, except for cataract and uveitis or retinal vascular disorders, were excluded. The institutional review board of Pusan National University Hospital approved the study protocol, and the protocol complied with the tenets of the Declaration of Helsinki.
Scleral buckling and vitrectomy combined with scleral encircling were usually used in young phakic RRD and severe proliferative vitreoretinopathy cases, respectively. Silicone oil tamponade after vitrectomy was applied in cases with failure to sufficiently remove subretinal fluid or the vitreoretinal proliferative membrane. We deemed vitrectomy with gas tamponade as the best choice in cases other than those described above.
All patients were operated on by a single surgeon (SW Park), who used the Constellation (Alcon Laboratories Inc., Fort Worth, TX) sutureless 23-gauge (G) or 25 G vitrectomy system and a noncontact wide viewing system, the Resight 700 (Carl Zeiss Meditec AG, Jena, Germany). Phacoemulsification was combined concurrently at the surgeon’s discretion. If necessary, to confirm the presence of posterior vitreous detachment or epiretinal membrane, triamcinolone acetonide was applied during the PPV. For shaving the peripheral vitreous, an assistant usually indented the sclera. Prophylactic laser photocoagulation was applied only around retinal breaks or lesions predisposed to retinal detachment, not on the normal-looking retina. During vitrectomy, perfluorocarbon liquid (PFCL) was used if necessary. Patients were instructed to maintain a face-down position for 1 to 3 days after the operation.
The patients were divided into two groups: the air group and the control group. The air group underwent vitrectomy after July 2014 and received only air tamponade. The control group underwent vitrectomy between January 2013 and June 2014 and received heterogeneous gas tamponade.
The following baseline characteristics were collected: type of gas, age, sex, intraocular pressure (IOP), lens status, axial length, high myopia, involvement of macula, number of retinal breaks, range of retinal detachment, presence of inferior breaks, use of PFCL during operation, and best-corrected visual acuity (BCVA), which was quantified using lines of Snellen visual acuity. The inferior breaks were defined as one or more breaks inside the retinal detachment located between the 4 and 8 o’clock positions.
The primary reattachment was defined as a retina reattached at 3 months after a single operation without any additional procedure. The primary reattachment rate was compared between the two groups. BCVA was compared at 1 and 3 months postoperative. IOP measurements at 1 and 7 days postoperative were analyzed. In the redetached cases, duration to detect the redetached retina, total number of surgeries, final BCVA, and presence of inferior breaks was investigated and compared.
All statistical analyses were performed using SPSS for Windows 21.0 (SPSS Inc., Chicago, IL). BCVA was converted to a logarithm of the minimum angle of resolution (logMAR) for statistical analysis. Differences between the two groups were assessed using an independent Student’s
The air group comprised 174 eyes in patients with primary RRD who underwent surgery for RRD over an 18-month period beginning in July 2014. Of these 174 eyes, the following were excluded: 51 eyes (29.3%) that received a scleral buckling procedure, 29 eyes (16.7%) that received a combined scleral buckling with vitrectomy, and 23 eyes (13.2%) that were treated with silicone oil as tamponade. Finally, a total of 71 eyes (40.8%) were included in the air group. The control group comprised 180 eyes in patients with primary RRD patients who underwent surgery for RRD for an 18-month period beginning in January 2013. Of these 180 eyes, the following were excluded: 64 eyes (35.6%) that received a scleral buckling procedure, 30 eyes (16.7%) that received a combined scleral buckling with vitrectomy, and 14 eyes (7.8%) that were treated with silicone oil as tamponade. Finally, a total of 72 eyes (40.0%) were included in the control group (Table
Choice of surgical method in each 18-month period.
Surgical methods | Before July 2014 ( |
After July 2014 ( |
|
---|---|---|---|
Vitrectomy + gas tamponade | 72 (40.0) | 71 (40.8) | 0.914 |
Scleral buckling | 64 (35.6) | 51 (29.3) | 0.214 |
Scleral buckling with vitrectomy | 30 (16.7) | 29 (16.7) | 1.000 |
Vitrectomy + silicone oil tamponade | 14 (7.8) | 23 (13.2) | 0.118 |
Total | 180 (100) | 174 (100) |
Baseline characteristics of each group.
Control group | Air group |
| |
---|---|---|---|
Type of gas ( |
15 : 55 : 2 | 71 : 0 : 0 | <0.001† |
Age (mean ± SD, yr) | 56.9 ± 9.8 | 58.6 ± 8.8 | 0.351 |
Sex (M : F) | 40 : 32 | 34 : 37 | 0.401† |
BCVA (mean ± SD, logMAR) | 1.38 ± 1.11 | 1.11 ± 1.05 | 0.143 |
IOP (mean ± SD, mmHg) | 13.6 ± 2.7 | 13.0 ± 3.1 | 0.237 |
Axial length (mean ± SD, mm) | 25.14 ± 2.11 | 24.83 ± 1.65 | 0.336 |
Proportion of high myopia ( |
23 (31.9%) | 16 (22.5%) | 0.282† |
Macula |
32 : 40 | 36 : 35 | 0.614† |
Number of retinal breaks |
1.8 ± 1.3 | 1.6 ± 1.0 | 0.315 |
Range of retinal detachment |
4.4 ± 1.7 | 4.6 ± 1.9 | 0.357 |
Lens state |
58 : 14 | 52 : 19 | 0.422† |
Inferior break ( |
28 (38.9%) | 18 (25.4%) | 0.111† |
Use of PFCL ( |
20 (27.8%) | 21 (29.6%) | 0.336† |
The primary reattachment was observed in 67 of 71 eyes (94.4%) in the air group and 68 of 72 eyes (94.4%) in the control group, with no significant difference between the groups (
In the air group, BCVA improved from 1.11 ± 1.05 logMAR (median, 20/125) at baseline to 0.23 ± 0.25 (median, 20/32) at 1 month and 0.18 ± 0.19 (median, 20/25) at 3 months postoperatively. In the control group, BCVA improved from 1.38 ± 1.11 logMAR (median, 20/300) at baseline to 0.33 ± 0.34 (median, 20/40) at 1 month and 0.20 ± 0.24 (median, 20/25) at 3 months. At 1 month postoperatively, BCVA was significantly better in the air group (
Clinical outcomes of each group.
Control group | Air group |
| |
---|---|---|---|
Primary reattachment rate ( |
68/72 (94.4%) | 67/71 (94.4%) | 0.951† |
Final reattachment rate ( |
72/72 (100.0%) | 71/71 (100.0%) | 1.000† |
BCVA (mean ± SD, logMAR) | |||
At 1 month | 0.33 ± 0.34 | 0.23 ± 0.25 | 0.021 |
At 3 months | 0.20 ± 0.24 | 0.18 ± 0.19 | 0.561 |
IOP (mean ± SD, mmHg) | |||
At 1 day | 17.2 ± 7.2 | 10.5 ± 3.1 | <0.001 |
At 7 days | 15.6 ± 5.9 | 15.1 ± 4.2 | 0.414 |
In the subgroup of redetached retina cases, surgical failure was recognized significantly earlier in the air group (9.3 ± 0.5 days) compared with that in the control group (21.3 ± 7.4 days) (
Subgroup analysis of the eyes with redetached retinas.
Control group | Air group |
| |
---|---|---|---|
Duration to detect the redetached (days) | 21.25 ± 7.44 | 9.25 ± 0.50 | 0.041 |
Total number of surgery | 2.25 ± 0.50 | 2.50 ± 0.58 | 0.686† |
Final BCVA (mean ± SD, logMAR) | 0.29 ± 0.28 | 0.22 ± 0.46 | 0.556 |
Inferior break ( |
2 (50%) | 1 (25%) | 0.465† |
In selected RRD cases where air was used as gas tamponade, noninferior results to long-acting gas have been reported [
Tamponades serve as a barrier to prevent the movement of fluid between the vitreous cavity and the subretinal space. Once adhesion between the retina and retinal pigment epithelium (RPE) has been established, the barrier is no longer needed. Theoretically, retina-RPE adhesion occurs within 24 hours in situations without subretinal fluid (SRF) [
The results of primary vitrectomy for RRD were first reported by Escoffery et al. [
Air tamponade has several advantages over long-acting gases, which require additional buying, keeping, and dilution, and it can reduce the cost and surgical time. Dilution and keeping these gases can lead to complications such as elevated IOP, faster absorption than expected, and toxicity due to gas contamination. Additionally, the results of the current study showed that visual recovery and recognition of surgical failure were faster using air. Although we found no significant difference in the final visual outcomes between the groups among the redetached retina cases, an earlier recognition of surgical failure would be expected to offer better outcomes [
This study had several limitations. First, there were selective biases due to the retrospective nature. The current study did not include all types of RRD. This study enrolled only simple cases. The cases with insufficient removal of SRF and vitreoretinal proliferative membrane were filled with silicone oil and excluded. The cases treated with scleral buckling or encircling were also excluded. Second, air was compared with heterogeneous gases rather than long-acting gases because we could not find a control group with comparable baseline characteristics who received a long-acting gas. Third, there was a time gap between the surgeries in the two groups, during which technical advances or surgical skill might have had an impact. However, we reasoned that 18 months was too short a time to have a large effect. Finally, while a 3-month follow-up was too short to determine visual outcome, it was enough to evaluate anatomical outcomes and helped to reduce selective biases. In spite of these limitations, the baseline characteristics were quite comparable and a wide spectrum of RRD cases was consecutively enrolled. The current results should be interpreted in consideration of these limitations, and large randomized prospective studies will be needed in the future.
Air used exclusively as gas tamponade in vitrectomy for RRD in a consecutive case series spanning 18 months delivered anatomical and visual outcomes that were comparable to those of the control group receiving heterogeneous gases and also to those described in recent reports [
The authors declare that there is no conflict of interest regarding the publication of this paper.