Surgically induced astigmatism in phacoemulsification, pars plana vitrectomy, and combined phacoemulsification and vitrectomy: a comparative study

LONG-TERM ANALYSIS OF INTRASCLERAL FIXATION OF INTRAOCULAR LENS: Trocar-Cannula-Based Sutureless Intrascleral Fixation Versus Sutured Scleral Fixation

PURPOSE

To compare the long-term outcomes of sutureless intrascleral fixation of the intraocular lens versus sutured scleral fixation.

METHODS

The authors retrospectively analyzed the medical records of patients who underwent intrascleral fixation of the intraocular lens using two different techniques: trocar-cannula-based sutureless fixation and sutured scleral fixation. Clinical outcomes were compared before and 1-, 3-, 6-, and 12-month follow-ups after the operation.

RESULTS

A total of 51 patients were followed over a 12-month period after the operation, including 28 eyes in the sutureless group and 23 eyes in the sutured group. Best-corrected visual acuity and spherical equivalent values reached targeted values faster in the sutureless scleral fixation of the intraocular lens. However, no significant difference was observed between the two groups. For intraocular lens capture, there was a statistically significant difference observed in the incidence of postoperative complications, which was demonstrated by one eye in the sutureless group and seven in the sutured group ( P = 0.009). To exclude the effect of corneal astigmatism, surgically induced astigmatism was calculated based on the astigmatism value 1 year after surgery. It was found that the sutureless technique significantly reduced the occurrence of astigmatism (2.43 ± 1.42 vs. 1.65 ± 0.94, P = 0.031).

CONCLUSION

In a 1-year follow-up period, the trocar-cannula-based sutureless technique was reliable and effective. Sutureless fixation was associated with fewer postoperative complications and lower surgically induced astigmatism values than those with sutured fixation.

Combining cataract surgery with 25-gauge high-speed pars plana vitrectomy: A prospective study

PURPOSE

To compare visual outcome and postoperative complications of combined 25-gauge pars plana vitrectomy and phacoemulsification with vitrectomy alone surgery in patients with epiretinal membrane and macular hole.

METHODS

A total of 110 eyes (73 eyes with epiretinal membrane and 37 eyes with macular hole) were enrolled in this prospective study. The eyes were divided into two groups: Group A included 55 eyes which underwent phacovitrectomy at the same time and Group B included 55 eyes which underwent vitrectomy alone. Follow-up visits were at 1, 3, and 6 months.

RESULTS

The best-corrected visual acuity correlation by analysis of variance measurement showed statistically non-significant differences between the two groups (p = 0.32). The post hoc analysis from baseline, 1°, 2°, and 3° follow-ups was not statistically significant (p > 0.05). The most common postoperative complication was cystoid macular edema that has been detected in 11 patients (10%) (seven eyes in Group A and four eyes in Group B): 2 patients (1.8%) developed a chronic macular edema. Intraocular hypertension occurred in five eyes (4.5%) (three in Group A and two in Group B). Four eyes (3.6%) underwent another surgical procedure for a persistent macular hole (two in Group A and two in Group B). The intraocular lens repositioning was performed one day after surgery in three eyes (2.7%) (Group A). The mean preoperative visual acuity was not different between the two groups (p = 0.80).

CONCLUSION

No significative differences between combined surgery and vitrectomy alone have been detected, in terms of postoperative complications and visual outcome.

Evaluation of corneal topographic changes and surgically induced astigmatism after transconjunctival 27-gauge microincision vitrectomy surgery

PURPOSE

To evaluate the corneal topographic changes and postvitrectomy astigmatism after 27-gauge (g) microincision vitrectomy surgery (MIVS) by using Pentacam HR-Scheimpflug imaging system.

METHODS

This prospective descriptive study included 30 eyes of 30 patients who underwent 27-g MIVS. All eyes underwent a Pentacam HR examination preoperatively and on the first week, first month and third month postoperatively. The power of the corneal astigmatism, mean keratometry (K m), K 1 and K 2 values and corneal asphericity (Q value) values for the both front and back surfaces of the cornea, index of surface variance (ISV), index of vertical asymmetry (IVA), index of height asymmetry (IHA), index of height decentration (IHD) and higher-order aberrations including coma, trefoil, spherical aberration, higher-order root-mean-square and total RMS were recorded. Additionally, the mean induced astigmatism was estimated by vector analysis.

RESULTS

No statistically significant changes were observed in the mean power of corneal astigmatism, mean keratometry, K 1 and K 2 values, corneal asphericity values, ISV, IVA, IHA, IHD and higher-order aberrations on the first week, first month and third month after the operation. The mean surgically induced astigmatism was calculated as 0.23 ± 0.11 D on the first week, 0.19 ± 0.10 D on the first month and 0.19 ± 0.08 D on the third month postoperatively.

CONCLUSION

Minor corneal surface and induced astigmatic changes are expected to result in rapid visual rehabilitation after pars plana vitrectomy with the 27-g MIVS system.

Intraocular lens power estimation in combined phacoemulsification and pars plana vitrectomy in eyes with epiretinal membranes: a case-control study

PURPOSE

To evaluate the accuracy of postoperative refractive outcomes of combined phacovitrectomy for epiretinal membrane (ERM) in comparison to cataract surgery alone.

MATERIALS AND METHODS

Thirty-nine eyes that underwent combined phacovitrectomy with intraocular lens (IOL) implantation for cataract and ERM (combined surgery group) and 39 eyes that received phacoemulsification for cataract (control group) were analyzed, retrospectively. The predicted preoperative refractive aim was compared with the results of postoperative refraction.

RESULTS

In the combined surgery group, refractive prediction error by A-scan and IOLMaster were -0.305±0.717 diopters (D) and -0.356±0.639 D, respectively, compared to 0.215±0.541 and 0.077±0.529 in the control group, showing significantly more myopic change compared to the control group (p=0.001 and p=0.002, respectively). Within each group, there was no statistically significant difference in refractive prediction error between A-scan and IOLMaster (all p>0.05). IOL power calculation using adjusted A-scan measurement of axial length based on the macular thickness of the normal contralateral eye still resulted in significant postoperative refractive error (all p<0.05). Postoperative refraction calculated with adjusted axial length based on actual postoperative central foveal thickness change showed the closest value to the actual postoperative achieved refraction (p=0.599).

CONCLUSION

Combined phacovitrectomy for ERM resulted in significantly more myopic shift of postoperative refraction, compared to the cataract surgery alone, for both A-scan and IOLMaster. To improve the accuracy of IOL power estimation in eyes with cataract and ERM, sequential surgery for ERM and cataract may need to be considered.

Postoperative refractive error after phacovitrectomy for epiretinal membrane with and without macular oedema

PURPOSE

This study was initiated to investigate whether the presence of macular oedema influenced intraocular lens (IOL) power calculation in eyes with epiretinal membrane.

METHODS

The files of patients undergoing combined phacoemulsification were retrospectively reviewed. Two groups were defined according to presence of macular oedema. The main outcome measure was the IOL power prediction error (PE). Secondary outcome measures were the correlation between preoperative macular thickness, absolute change of macular thickness and dioptric shift. The mean postoperative PE achieved with the Haigis formula was compared with the PE that would have been obtained had the SRKII and HofferQ formulas been used.

RESULTS

We investigated 47 eyes of 47 consecutive patients. Regardless of the IOL formula used, the PE was on average higher in eyes without macula oedema (group 1). The myopic dioptric shift was dependent on preoperative macular thickness and absolute change of macular thickness. This association was more markedly pronounced in group 1.

CONCLUSIONS

Increased retinal thickness is the main cause for underestimation of the cornea-photoreceptor layer distance, and therefore could contribute to inaccuracy in IOL power calculations. The current results show that a myopic shift tends to be less pronounced in cases where a macula oedema is present. Eyes with pure traction have less predictable refractive results in terms of higher PE and dioptric shift.

23- and 20-gauge vitrectomy with air tamponade with combined phacoemulsification for idiopathic macular hole: a single-surgeon study

PURPOSE

To compare the results of 23- and 20-gauge vitrectomies combined with phacoemulsification and aspiration and intraocular lens implantation (phacoemulsification surgery) 1 year after repair of idiopathic macular holes.

DESIGN

Retrospective, consecutive, comparative case series.

METHODS

The medical charts of 100 consecutive eyes were reviewed that had undergone either 23- or 20-gauge vitrectomy combined with phacoemulsification surgery to treat an idiopathic macular hole performed by 1 surgeon. The rate of improvement of the logarithm of the minimal angle of resolution visual acuity (VA) was calculated using the formula: (postoperative value - preoperative value) × 100/(1-year postoperative value - preoperative value).

RESULTS

The macular holes closed successfully after the primary vitrectomy in all eyes in both groups. Although the VAs did not differ significantly before surgery or 1 year after surgery between the 2 groups, the VA improvement was significantly greater 1 and 3 months after surgery (P = .02, for both) in the 23-gauge group compared with the 20-gauge group. The induced corneal astigmatism levels 1 week and 1 and 3 months after surgery were significantly lower (P = .01, P = .01, and P = .03, respectively) and the surgical time was significantly shorter (P = .01) in the 23-gauge group than in the 20-gauge group. No apparent complications developed in either group.

CONCLUSIONS

Since 23-gauge vitrectomy combined with phacoemulsification surgery is advantageous because the VA improved rapidly after treating the macular holes with an acceptable safety profile, idiopathic macular holes are a good indication for 23-gauge vitrectomy combined with phacoemulsification surgery.