Comparison of corneal endothelial cell loss during phacoemulsification using continuous anterior chamber infusion versus those using ophthalmic viscosurgical device: randomized controlled trial

The safety and efficacy of phacoemulsification surgery in uncomplicated cataracts with and without an ophthalmic-viscosurgical-device

PURPOSE

To compare and evaluate the results of phacoemulsification surgery involving and not involving an ophthalmic-viscosurgical-device (OVD).

METHODS

A prospective, randomized controlled trial included 60 eyes of 60 patients scheduled to receive phacoemulsification surgery. In order of presentation, patients were randomized into two groups to undergo different surgical techniques: the OVD-free group (n = 30) and the OVD group (n = 30). Each patient's operating time, total ultrasonography (U/S) time, cumulative dissipated energy (CDE), aspiration time, and volume of balanced salt solution (BSS) aspirated were recorded. At 1 day, 1 week, and 1 and 3 months postoperation, measurements of endothelial cell density (ECD) and intraocular pressure (IOP), were taken and compared between the groups.

RESULTS

Total U/S time (p = .567) and CDE (p = .168) were similar between the groups. In the OVD group, operating time (p = .011), aspiration time (p < .001), and volume of BSS aspirated (p < .001) were greater than in the OVD-free group. The change in ECD between the groups was not statistically significant at all visits (p = .433, p = .147, p = .379, p = .534; respectively). Although IOP increased in the OVD group at 1 day postoperation (p = .001), no difference emerged between the groups at 3 months postoperation (p = .121).

CONCLUSION

Phacoemulsification surgery without an OVD took less time than with the OVD and caused no significant loss in ECD. Surgeons concerned about elevated IOP following cataract surgery should apply the OVD-free method.

Corneal endothelial protection during manual small-incision cataract surgery: A narrative review

Cataract causes bilateral blindness in 20 million people globally, the vast majority of whom live in developing countries. Manual small-incision cataract surgery (MSICS) has emerged as an efficient and economical alternative to phacoemulsification, giving comparable results in terms of final visual gain. One of the important determinants of postoperative visual gain is the status of the corneal endothelium. Multiple factors such as corneal distortion, irrigation solution turbulence, mechanical trauma by instruments, nuclear fragments, intraocular lens contact, and free oxygen radicals, all have been implicated in causing corneal damage during cataract surgery. MSICS with posterior chamber intraocular lens implantation has been reported to cause an endothelial cell loss of 15.83%, which is comparable with other modes of cataract surgery like extracapsular cataract extraction and phacoemulsification. Thorough preoperative assessment of endothelial status and taking necessary steps for endothelial protection during surgery can decrease the endothelial cell loss and overall burden of pseudophakic bullous keratopathy. In addition to surgical techniques, the type of irrigating solutions, ocular viscoelastic devices, intracameral dyes, and drugs all affect the endothelial cell status. This review presents a summary of available literature on the protection of endothelial cells during different steps of MSICS. This is especially relevant for developing countries where large-scale MSICS cataract surgeries are performed to decrease the cataract blindness burden.

Comparison of corneal endothelial cell loss during manual small-incision cataract surgery using viscoelastic-assisted nucleus removal versus continuous balanced salt solution plus technique - Randomized controlled trial

Purpose

The purpose of this study was to compare and analyze the endothelial cell loss during manual small-incision cataract surgery (MSICS) using the viscoelastic-assisted nucleus removal versus basal salt solution plus technique.

Methods

This was a prospective randomized trial of 204 patients who underwent MSICS using viscoelastic-assisted nucleus removal (Group 1- OVD) versus basal salt solution plus technique (Group 2- BSS) at a tertiary eye care hospital in North India from January 2018 to 2021. Of these 204 patients, 103 (50.5%) and 101 (49.5%) were allocated to Group 1 and 2, respectively. The parameters assessed were detailed history, demographics, and anterior and posterior segment details. Visual acuity, intraocular pressure (IOP), keratometry, pachymetry, and endothelial cell density were evaluated preoperatively and postoperatively on day 1 and 30.

Results

The mean age of the patients was 64.5 ± 8.2 years (range 48-82 years). There were 129 (63.2%) males and 75 (36.8%) females. The mean LogMAR visual acuity for both groups on day 1 (Group 1- 0.3 ± 0.1, Group 2- 0.5 ± 0.2) and day 30 (Group 1- 0.1 ± 0.2, Group 2- 0.1 ± 0.1) was statistically significant (P &lt; 0.001), and the mean IOP value showed a statistically significant value (P &lt; 0.009) on day 1 in Group 2 (15.0 ± 2.4 mmHg) and on day 30 (P &lt; 0.001) in both the groups (Group 1- 13.6 ± 1.8 mmHg, Group 2- 13.5 ± 2 mmHg). The horizontal and vertical k values also showed a statistically significant difference on day 1 and day 30 (P &lt; 0.001). The mean percentage change of central corneal thickness (CCT) in Group 1 was 17.7% and in Group 2 was 17.4% on day 1, and it was 1.1% on day 30 in both the groups, which was statistically significant (P &lt; 0.001) compared to preoperative values. The percentage change in endothelial cell density on day 1 was 9% in Group 1 and 4.6% in Group 2, which was statistically significant (P &lt; 0.001). On day 30, it was 9.7% and 4.8%, respectively, which was statistically significant (P &lt; 0.001).

Conclusion

Our study highlights statistically significant endothelial cell loss with viscoelastic-assisted nuclear delivery compared to BSS-assisted nuclear delivery during MSICS in a short follow-up of 1 month. The CCT values showed a slight increase, and the keratometry and IOP were unaffected compared to the preoperative parameters in both the groups.

Corneal endothelial cell density loss following glaucoma surgery alone or in combination with cataract surgery: A systematic review and meta-analysis

TOPIC

Corneal endothelial cell density (ECD) loss following glaucoma surgery with or without cataract surgery.

CLINICAL RELEVANCE

Corneal ECD loss may occur due to intraoperative surgical trauma in glaucoma surgery or postoperatively with chronic endothelial cell trauma or irritation.

METHODS

Trabeculectomy, glaucoma filtration surgery or microinvasive glaucoma surgery in participants with ocular hypertension, primary and secondary open angle glaucoma, normal tension glaucoma and angle-closure glaucoma were included. Pediatric populations and participants with pre-existing corneal disease were excluded. Laser treatments and peripheral iridotomy were excluded. Electronic databases searched in December 2021 included MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov and The International Prospective Register of Systematic Reviews (PROSPERO), FDA PMA and FDA 510(k).

RESULTS

39 studies were included in quantitative synthesis. 12 months following suprachoroidal MIGS mean ECD loss was 282 cells/mm² (95% Confidence Interval (CI) 220 to 345; p <0.00001; Chi² = 0.06; I² = 0%; 2 studies; very low certainty). Mean ECD loss after Schlemm's canal implantable devices was 338 cells/mm² (95% CI 185 to 491; p<0.0001; Chi² = 0.08; I² = 0%; 2 studies; low certainty) at 12 months. When compared to phacoemulsification alone, Schlemm's canal implants combined with phacoemulsification showed statistically significant mean ECD reduction at 24 months; mean difference of ECD was -19% (95% CI -37% to -2%; p=0.03; Chi² = 3.04; I² = 34%; 3 studies; low certainty). Mean ECD loss was 64 cells/mm² (95% CI 21 to 107; p=0.004; Chi² = 4.55; I² = 0%; 6 studies; low certainty) following Schlemm's canal procedures (without implantable devices) at 12 months. At 12 months the mean ECD loss after trabeculectomy was 33 cells/mm² (95% CI -38 to 105, p=0.36, Chi² = 1.17; I² = 0%; moderate certainty). At 12 months mean ECD loss was 121 cells/mm² (95% CI 53 to 189; p=0.0005; Chi² = 3.00; I² = 0%; 5 studies; low certainty) after Express implantation. When compared to control fellow eye, aqueous shunt surgery reduced ECD by 5.75% (95% CI -0.93 to 12.43; p=0.09 Chi² = 1.32; I² = 0%; low certainty) and 8.11% ECD loss (95%CI 0.06 to 16.16 p=0.05; Chi²= 1.93; I²=48%) at 12 and 24 months, respectively.

CONCLUSIONS

Overall there is low certainty evidence to suggest that glaucoma surgery involving long-term implants has a greater extent of ECD loss than glaucoma filtration surgeries without the use of implants. The results of this review support long-term follow-up (beyond 36 months) to assess ECD loss and corneal decompensation following implantation of glaucoma drainage implants.

Effect of Anterior Chamber Instability during Phacoemulsification Combined with Intraocular Lens Implantation

Purpose

To determine the incidence of anterior chamber (AC) instability during phacoemulsification (phaco) combined with intraocular lens implantation and investigate its effect on intraocular tissues.

Methods

Among the 248 enrolled eyes, 121 and 127 eyes were categorized into the irrigation and nonirrigation groups, respectively, depending on the use of a self-made anterior chamber maintainer (ACM) during phaco. AC stability was evaluated using operating microscopy and intraoperative optical coherence tomography (iOCT). Slit-lamp examination of AC flare and cells was performed 1 day postoperatively. Corrected distance visual acuity (CDVA), intraocular pressure (IOP), endothelial cell density (ECD), central corneal thickness (CCT), posterior vitreous detachment (PVD), and central foveal thickness (CFT) were evaluated preoperatively and at 1 week, 1 month, and 3 months postoperatively.

Results

There was good consistency in AC stability evaluation between operating microscopy and iOCT. The incidence of AC instability was significantly different between groups after the phaco and irrigation/aspiration tips were withdrawn from the AC (P < 0.001). At 1 day postoperatively, after excluding eyes in which the AC could not be visualized, AC cell grades were significantly lower in the irrigation group (P = 0.014). There was no significant difference in CDVA, IOP, ECD, and CCT between groups during the 3-month follow-up (P > 0.05). At 1 month and 3 months postoperatively, PVD occurred in 8 (16.3%) and 14 (28.6%) eyes and in 22 (40.7%) and 37 (68.5%) eyes in the irrigation and nonirrigation groups, respectively (P = 0.006 and P < 0.001). CFT was significantly higher in the nonirrigation group at 1 and 3 months postoperatively (P = 0.018 and P = 0.010).

Conclusions

Both operating microscopy and iOCT are efficient for AC stability evaluation. When the phaco and I/A tips were withdrawn from the AC, there was frequent instability. Intraoperative AC instability can increase surgery-induced inflammation and lead to postoperative complications such as PVD, retinal detachment, and macular edema. The self-made ACM can effectively reduce the incidence of intraoperative AC instability and these complications.

Corneal endothelial damage in phacoemulsification using an anterior chamber maintainer compared with using an ophthalmic viscosurgical device

PURPOSE

To compare the effects of phacoemulsification surgery (PE) using an anterior chamber maintainer (ACM) and conventional PE using an ophthalmic viscosurgical device (OVD) on corneal endothelial cells.

SETTING

Department of Ophthalmology, Celal Bayar University, Manisa, Turkey.

DESIGN

Prospective randomized controlled trial.

METHODS

Eyes in the OVD group (n = 50) underwent conventional PE, whereas eyes in the ACM group (n = 50) underwent PE using an ACM. Endothelial cell density (ECD), coefficient of variation (CV), hexagonality (HEX), and noncontact central corneal thickness (CCT) measurements were performed by specular microscopy before and at 1 month, 3 months, and 6 months after PE.

RESULTS

This study included 100 eyes of 97 patients undergoing PE. The mean age was 64.7 ± 10.6 years in the OVD group, 64.0 ± 12.6 years in the ACM group (P > .05). The groups did not differ significantly in preoperative ECD, CV, HEX, and CCT or total PE time (P > .05 for all). ECD was significantly lower in the ACM group compared with the OVD group at postoperative 1 month, 3 months, and 6 months (P = .002, P = .002, and P = .001, respectively). Similarly, ECD loss compared with preoperative value was greater in the ACM group at all postoperative timepoints (P = .003, P = .001, and P = .001, respectively). CV increased and HEX decreased in both groups postoperatively (P > .05 for both). CCT showed a transient increase of less than 10 μm at postoperative 1 month in both groups (P = .296).

CONCLUSIONS

PE with ACM was associated with greater corneal ECD loss compared with conventional PE. ACM should not be used during PE in patients with limited corneal endothelial reserve.

The Effects of Glaucoma and Glaucoma Therapies on Corneal Endothelial Cell Density

A healthy corneal endothelium is required for corneal clarity. Both the glaucoma disease state and its various forms of treatment can have adverse effects on the corneal endothelium. Both the presence of glaucoma and the magnitude of intraocular pressure elevation are related to endothelial cell loss (ECL). Topical medical therapy, laser procedures, and both traditional surgeries-trabeculectomy and tube-shunts-and newer minimally invasive glaucoma surgeries have variable effects on ECL. This review will summarize the reported effects of glaucoma and its treatment on ECL. Concerns for corneal endothelial cell health should be part of the decision-making process when planning glaucoma therapy for lowering intraocular pressure, with added caution in case of planned device implantation in eyes with preexisting ECL and low endothelial cell density at high risk for corneal endothelial decompensation.

Non-contact specular microscopy with Topcon instruments to assess central corneal thickness of healthy human eyes - A 20 year review

BACKGROUND

The purpose of this review was to evaluate the consistency of central corneal thickness (CCT) values reported with use of Topcon SP-2000 P and SP-3000 P non-contact specular microscopes since their introduction in 1999 with the two microscopes having been commonly used in a wide range of studies.

METHODS

As a primary resource, PubMed was used to search for peer-reviewed articles in any language that included CCT values obtained with non-contact specular microscopy reported for humans with nominally healthy corneas. Relevant articles were obtained and any cited publications also checked.

RESULTS

A total of 76 articles were identified which reported CCT on different small-to-moderate sized groups of individuals, published between 1999 and 2019. From these, an overall group mean CCT value of 0.525 ± 0.013 mm (median 0.525 mm) can be calculated. An estimated 95 % confidence interval (CI, based on 1.96 SD) would be between 0.500 and 0.550 mm. For the two Topcon models, the group mean ± SD values were 0.529 ± 0.013 mm and 0.517 ± 010 mm respectively. An assessment of the CCT data sets in relation to the reported average age indicated no statistically significant effect (p = 0.289, r = -0.129). Very similar average CCT values were also encountered in 4 other reports where these microscopes were used in large-scale population studies as well as in 2 other reports using the newer Topcon SP-1 P model.

CONCLUSIONS

The Topcon stand-alone non-contact specular microscopes have yielded consistent and predictable corneal thickness measures over many years.

[Energy load and state of corneal endothelium in hybrid (femtosecond laser-assisted) and torsional phacoemulsification]

Postoperative state of the corneal endothelium is the most important criterion for evaluating the safety of cataract phacoemulsification.

PURPOSE

To compare the intraoperative energy load and postoperative state of corneal endothelium in hybrid (femtosecond laser-assisted) and torsional phacoemulsification.

MATERIAL AND METHODS

The study analyzed surgical outcomes of 603 patients (714 eyes) divided into 3 groups: 225 patients (267 eyes) underwent modified femtosecond laser-assisted phacoemulsification (1st group), 237 patients (278 eyes) underwent standard femtosecond laser-assisted phacoemulsification (2nd group), and 141 patients (169 eyes) who underwent torsional phacoemulsification (3rd group). The follow-up period lasted up to 2 years.

RESULTS

In patients with grade II lens density (here and further - L. Buratto classification is used), effective ultrasound time was 0.56±0.11 s in the 1st group, 0.83±0.17 s in the 2nd group, and 2.78 ± 0.51 s in the 3rd group (p(1-2)<0.05; p(1-3)<0.05; p(2-3)<0.05). In patients with grade III lens density effective ultrasound time was 2.04±0.37 s in the 1st group, 2.97±0.53 s in the 2nd group, and 4.59±0.91 s in the 3rd group (p(1-2)<0.05; p(1-3)<0.05; p(2-3)<0.05). In patients with grade IV lens density, effective ultrasound time was 3.95±0.81 s in the 1st group, 5.11±1.03 s in the 2nd group, and 8.37±1.73 s in the 3rd group (p(1-2)<0.05; p(1-3)<0.05; p(2-3)<0.05). In patients with grade II lens density, loss of endothelial cells was 3.3±1.1% in the 1st group, 3.7±1.2% in the 2nd group, and 4.3±1.2% in the 3rd group (p(1-2)>0.05; p(1- 3)<0.05; p(2-3)<0.05). In patients with grade III lens density, loss of endothelial cells was 5.1±1.4% in the 1st group, 5.7±1.5% in the 2nd group, 7.2±1.7% in the 3rd group (p(1-2)>0.05; p(1-3)<0.05; p(2-3)<0.05). In patients with grade IV lens density, loss of endothelial cells was 8.9±2.1% in the 1st group, 10.1±2.3% in the 2nd group, and 13.3±2.5% in the 3rd group (p(1-2)>0.05; p(1-3)<0.05; p(2- -3)<0.05).

CONCLUSION

Both techniques of femtosecond laser-assisted phacoemulsification significantly reduce the effective ultrasound time (p<0.05) and the degree of corneal endothelial cells loss (p<0.05) compared with torsional phacoemulsification.

Corneal Endothelial Cell Loss and Morphometric Changes 5 Years after Phacoemulsification with or without CyPass Micro-Stent

PURPOSE

To characterize long-term changes in corneal endothelial cells after phacoemulsification with or without supraciliary Micro-Stent (Alcon) implantation in eyes with open-angle glaucoma (OAG) and visually significant cataract.

DESIGN

Three-year safety extension of a 2-year randomized clinical trial.

METHODS

Patients from the multicenter Study of an Implantable Device for Lowering Intraocular Pressure in Glaucoma Patients Undergoing Cataract Surgery (COMPASS) trial who underwent Micro-Stent implantation plus phacoemulsification (n = 282) or phacoemulsification alone (n = 67) were analyzed post hoc. Specular microscopy was used to assess endothelial cell loss (ECL), including changes from baseline in endothelial cell density (ECD), coefficient of variation, and percentage of hexagonal cells.

RESULTS

Preoperative ECDs in the microstent group (2,432.6 cells/mm² [95% confidence interval [CI], 2,382.8-2,482.4 cells/mm²]) were similar to those in the control group (2,434.5 cells/mm² [95% CI, 2,356.5-2,512.4 cells/mm²]) groups. ECL at months 48 and 60 was greater in the Micro-Stent group than in the control group. At month 60, the mean percent of changes in ECD was -20.4% (95% CI, -23.5% to -17.5%) in the Micro-Stent group and -10.1% (95% CI, -13.9% to -6.3%) in the control group. No statistically significant between-group changes from baseline in cellular morphology were observed. Nine adverse events were possibly related to ECL, including 3 eyes with transient focal corneal edema and 4 eyes that required Micro-Stent trimming due to protrusion.

CONCLUSIONS

In eyes with OAG, ECL after phacoemulsification is acute and stabilizes after 3 months, whereas ECL after phacoemulsification plus Micro-Stent implantation proceeds for at least 5 years. Clinical findings associated with ECL in these eyes were uncommon (3.3% of implanted eyes), suggesting that ECL is generally a subclinical phenomenon.

Comparative analysis of endothelial cell loss following phacoemulsification in pupils of different sizes

Purpose:

To compare Endothelial cell(EC) loss following Phacoemulsification (PKE) in pupils of different sizes.

Methods:

A prospective double masked observational study in which a total of 150 eyes of 150 patients between 50 & 70 years of age with senile cataract of nuclear sclerosis grade II were enrolled. Patients were allocated into three groups of 50 eyes each in Group A (pupil size <5 mm), Group B (pupil size 5–7 mm) and Group C (pupil size >7 mm). Pupillary size was measured by determining the height of slit on slit-lamp biomicroscope examination. PKE was done by the same expert surgeon using vertical chop technique and a foldable intraocular lens was implanted in the capsular bag. Corneal EC count and pachymetry were performed twice and average of 2 readings was taken for the purpose of this study. Measurements were taken preoperatively and postoperatively on day 1, day 7 and day 30.

Results:

The mean EC count loss on postoperative day 1 in Group A was 19.45%, Group B 14.89%, Group C 10.19% with statistical significant difference between Group A and Group B, as also Group A and Group C. The difference was not significant between Group B and Group C, though there was a fall in EC count in Group C as well. Increase in corneal thickness on postoperative day 1 in group A was 5.43%, Group B 3.55%, Group C 2.14% with statistical significant difference between Group A and Group B, as also Group A and Group C with no difference in Group B and Group C.

Conclusion:

PKE done in eyes with maximal pupillary dilatation of <5 mm causes a greater EC loss and results in thicker corneas postoperatively as compared to eyes with pupillary dilatation of >5 mm at the end of one month.

Comparison of central corneal thickness and endothelial cell measurements by Scheimpflug camera system and two noncontact specular microscopes

PURPOSE

To investigate the correlation of Scheimpflug camera system and two noncontact specular microscopes in terms of central corneal thickness (CCT) and corneal endothelial cell morphology measurements.

METHODS

One hundred eyes of 50 healthy subjects were examined by Pentacam Scheimpflug Analyzer, CEM-530 (Nidek Co, Ltd, Gamagori, Japan) and CellChek XL (Konan Medical, California, USA) via fully automated image analysis with no corrections made. Measurement differences and agreement between instruments were determined by intraclass correlation analysis.

RESULTS

The mean age of the subjects was 36.74 ± 8.59 (range 22-57). CCTs were well correlated among all devices, with having CEM-530 the thinnest and CellChek XL the thickest measurements (intraclass correlation coefficient (ICC) = 0.83; p < 0.001 and ICC = 0.78; p < 0.001, respectively). Mean endothelial cell density (ECD) given by CEM-530 was lower than CellChek XL (2613.17 ± 228.62 and 2862.72 ± 170.42 cells/mm², respectively; ICC = 0.43; p < 0.001). Mean value for coefficient of variation (CV) was 28.57 ± 3.61 in CEM-530 and 30.30 ± 3.53 in CellChek XL. Cell hexagonality (HEX) with CEM-530 was higher than with CellChek XL (68.70 ± 4.16% and 45.19 ± 6.58%, respectively).

CONCLUSIONS

ECDs with CellChek XL and CEM-530 have good correlation, but the values obtained by CellChek XL are higher than CEM-530. Measurements for HEX and CV differ significantly and show weak correlation. Thus, we do not recommend interchangeable use of CellChek XL and CEM-530. In terms of CCTs, Pentacam, CEM-530 and CellChek XL specular microscopy instruments are reliable devices.

Changes in corneal endothelium cell characteristics after cataract surgery with and without use of viscoelastic substances during intraocular lens implantation

PURPOSE

To evaluate whether the use of balanced salt solution (BSS) or an ophthalmic viscoelastic device (OVD) during hydrophilic acrylic intraocular lens (IOL) implantation variously impacts corneal endothelial cell characteristics in eyes undergoing uneventful phacoemulsifications.

METHODS

Prospective nonrandomized observational clinical trial. Patients were assigned either to the BSS plus(®) or to the OVD Z-Celcoat™ group depending on the substance used during IOL implantation. Corneal endothelium cell characteristics were obtained before, 1 week, and 6 weeks after surgery. Intraoperative parameters (eg, surgery time, phacoemulsification energy) were recorded.

RESULTS

Ninety-seven eyes were assigned to the BSS plus and 86 eyes to the Z-Celcoat group. Preoperative corneal endothelium cell density (ECD) and endothelium cell size were 2,506±310 cells/mm(2)/2,433±261 cells/mm(2) and 406±47 µm(2)/416±50 µm(2) (P=0.107/P=0.09). After 1 and 6 weeks, ECD decreased and endothelium cell size increased significantly in both groups (each P<0.001) without significant differences between both groups (each P>0.05). Irrigation-aspiration suction time (30.3±16.6 versus 36.3±14.5 seconds) and overall surgical time (7.2±1.2 versus 8.0±1.4 minutes) were significantly longer in the OVD Z-Celcoat group (each P<0.001). No complications or serious side effects occurred.

CONCLUSION

Implantation of a hydrophilic acrylic IOL under BSS infusion seems to be a useful and faster alternative in experienced hands without generating higher ECD loss rates.

Femtosecond laser-assisted cataract surgery without OVD: a prospective intraindividual comparison

PURPOSE

To compare femtosecond laser-assisted cataract surgery without the use of ophthalmic viscosurgical device (OVD) with standard phacoemulsification using OVD.

METHODS

This was a prospective, randomized, single-center trial of 37 patients (74 eyes) diagnosed as having significant cataract in both eyes. Randomly, one eye underwent standard phacoemulsification with OVD (the OVD group); this group acted as controls. The other eye was treated with the femtosecond laser; the subsequent manual part of the procedure was performed without OVD (non-OVD group). Time of surgery, amount of fluid used during phacoemulsification, central corneal thickness, intraocular pressure, endothelial cell count, and visual acuity were documented over the 6-month follow-up.

RESULTS

There were no major complications and no significant difference in overall surgery time (non-OVD: 375 ± 81 seconds; OVD: 362 ± 43 seconds; P = .713) and in the quantity of fluid passing through the eye (non-OVD: 187 ± 35 mL; OVD: 186 ± 27 mL; P = .952) between groups. Endothelial cell loss after 6 months was not significantly different between groups (non-OVD: -2.4%; OVD: -2.7%; P = .880). Central corneal thickness was not different at 1 week postoperatively between groups (non-OVD: 575 ± 45 µm; OVD: 573 ± 46 µm; P = .820). Three patients in the OVD group and one patient in the non-OVD group experienced intraocular pressure greater than 25 mm Hg at 1 day postoperatively. There were no significant differences in corrected distance visual acuity between groups (logMAR non-OVD: 0.024; OVD: 0.038; P = .461).

CONCLUSIONS

Femtosecond laser-assisted treatment allows the cataract surgeon to perform phacoemulsification and intraocular lens implantation without the use of OVD at no additional risk to the corneal endothelium. Furthermore, there was a tendency toward fewer increases in intraocular pressure in patients treated with the femtosecond laser.

Safety of hydroimplantation: a foldable intraocular lens implantation without the use of an ophthalmic viscosurgical device

PURPOSE

To compare the safety of a single-piece, foldable intraocular lens (IOL) hydroimplantation with that of a standard implantation using an ophthalmic viscosurgical device (OVD).

METHODS

One hundred consecutive patients with bilateral age-related cataract surgery were enrolled into a prospective double-blind study. Each patient's first eye was randomly assigned to a standard implantation technique with an OVD or the hydroimplantation technique, while the fellow eye received the opposite technique. The main outcomes measured were endothelial cell loss, postoperative changes of intraocular pressure (IOP), and the frequency of complications.

RESULTS

The reduction of endothelial cell density 1 month and 6 months after the surgery was 9.76% ± 13.5%, 10.7% ± 12.6%, respectively, in group A (OVD) and 9.07% ± 12.7%, 9.13% ± 13.7%, respectively, in group B (hydroimplantation). The differences were not statistically significant. The mean IOP 2 hours after surgery was 10.19 ± 6.78 mm Hg in group A and 9.92 ± 7.01 mm Hg in group B. Twenty-four hours and 1 month after surgery, the mean IOP was 14.52 ± 5.59 mm Hg and 13.21 ± 3.5 mm Hg, respectively, in group A, and 15.45 ± 5.77 mm Hg and 13.1 ± 3.44 mm Hg, respectively, in group B. The differences between groups A and B were not statistically significant.

CONCLUSIONS

The hydroimplantation technique is a safe technique for single-piece foldable IOL implantation. There was no increase in intraoperative and postoperative complications compared with the standard implantation technique using an OVD.

Comparison of OVD and BSS for maintaining the anterior chamber during IOL implantation

PURPOSE

To compare surgical results between conventional intraocular lens (IOL) implantation using an ophthalmic viscosurgical device (OVD) and IOL implantation using a balanced salt solution (BSS) after irrigation/aspiration (I/A) of the lens cortex.

METHODS

A randomized prospective study was conducted on 62 patients who underwent cataract surgery. Following completion of conventional I/A of the lens cortex, we divided patients into two groups according to whether or not BSS was used. In group A (n = 31), the anterior chamber and the capsular bag were completely filled with an OVD before IOL implantation. On the other hand, in group B (n = 31), BSS was irrigated into the anterior chamber through a previous side port during IOL implantation. Surgical results were compared between the two groups.

RESULTS

In both groups, IOP peaked six hours after surgery. The occurrence of an IOP spike by postoperative day one was observed in six cases (6 / 31) in group A and in no cases (0 / 31) in group B, a difference that was statistically significant (p = 0.024). The values of endothelial cell density, central corneal thickness, anterior chamber inflammation, myopic shift, and posterior capsule opacification were not significantly different between the two groups.

CONCLUSIONS

Compared with the use of OVD for IOL implantation, use of BSS during IOL implantation resulted in reductions in postoperative IOP spike and OVD removal time.