Effect of carbachol on intraocular pressure in small-incision cataract surgery

Sixty patients, who underwent phacoemulsification and implantation of a folded polyHema intraocular lens were assigned to two groups. Following wound closure 0.5 ml of 0.01% carbachol or balanced salt solution was instilled into the anterior chamber. Healon was used in all eyes but evacuated from the capsular bag behind the intraocular lens and the anterior chamber. Intraocular pressure was measured the day before as well as 6 and 18 hours postoperatively. At 6 hours the mean change of intraocular pressure from baseline was ±2.8 ± 5.3 mmHg in the carbachol group compared with +4.7 ± 8.0 mmHg in the BSS group (p < 0.0001). At 18 hours the mean change from baseline was ±3.0 ± 4.6 mmHg in the treatment group and +2.3 ± 8.5 in the control group (p < 0.0001). Intraocular pressure exceeding 25 mmHg at 6 hours was observed in 8 (27%) eyes of the control group but none of the treatment group. At 18 hours 4 (13%) eyes of the control group and 1 (3%) of the carbachol group still had an increase of intraocular pressure. Summarizing our results we conclude that the effect of Healon on the postoperative intraocular pressure is successfully counteracted by its aspiration from the capsular bag and the anterior chamber, especially when carbachol is used for intraoperative miosis.     

Effect of acetylcholine on intraocular pressure following small-incision cataract surgery.

40 patients, who underwent phacoemulsification and implantation of a polyHema intraocular lens (IOGEL-1103) were assigned to two groups. After evacuation of Healon from the capsular bag behind the lens and the anterior chamber, either 0.5 ml of 1% acetylcholine chloride or 0.5 ml of balanced salt solution was injected into the anterior chamber. When compared with preoperative values, the mean intraocular pressure (IOP) 6 h postoperatively was unchanged in the acetylcholine group (0 +/- 8.5 mm Hg) but increased in the control group (+4.1 +/- 7.4 mm Hg). 18 h postoperatively, the mean intraocular pressure slightly decreased in the acetylcholine group (-0.5 +/- 6.1 mm Hg) compared with an increase of +1.4 +/- 4.4 mm Hg in the control group. Intraocular pressure exceeding 25 mm Hg was observed at 6 h in 2 (10%) patients of the acetylcholine group and in 4 (20%) of the control group. At 18 h, intraocular pressure was elevated in only 1 (5%) patient of the acetylcholine group and in 3 (15%) of the control group. From these results, we conclude that the evacuation of Healon from the capsular bag behind the implanted lens and acetylcholine reduce the incidence of postoperative elevations of intraocular pressure.     

Immediate changes in intraocular pressure after clear corneal micro-incision versus small-incision cataract surgery

Purpose

We sought to examine changes in intraocular pressure (IOP) in the immediate period after clear corneal micro-incision cataract surgery (MICS) and after small-incision cataract surgery (SICS).

Methods

Sixty-eight eyes of 34 patients scheduled for coaxial phacoemulsification were randomized into one of two groups: (a) eyes that were to undergo a 2.0-mm MICS, and (b) a 2.65-mm SICS. At the conclusion of surgery, the IOP was adjusted to the range between 15–40 mmHg with stromal hydration. The IOP was measured using a rebound tonometer preoperatively, at the conclusion of surgery, and at 3, 6, 9, 12, and 15 min postoperatively. The Seidel test and anterior segment-optical coherence tomography were performed at 20 min postoperatively.

Results

Mean IOP at the conclusion of surgery was 27.7 ± 4.7 mmHg in the MICS group and 29.7 ± 5.1 mmHg in the SICS group (p = 0.1239). In both groups, mean IOP decreased to the preoperative level within 9 min postoperatively and did not change significantly for up to 15 min. Mean IOP was similar between the MICS and SICS groups throughout the observation period (p ≥ 0.1239). Hypotony (≤10 mmHg), positive Seidel test, and loss of wound coaptation were not detected in all eyes.

Conclusions

After adjusting the IOP to a relatively high level at the conclusion of surgery, the IOP decreased within 9 min and was stable within 15 min without hypotony. The IOP was comparable between eyes after MICS and SICS, and both incisions virtually closed within 20 min postoperatively.     

Removal times for a dispersive and a cohesive ophthalmic viscosurgical device correlated with intraocular lens material

PURPOSE: To investigate the removal times of ophthalmic viscosurgical devices (OVDs) with different intraocular lens (IOL) designs and materials. SETTING: Center for Research on Ocular Therapeutics and Biodevices, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA, and Heidelberg IOL & Refractive Surgery Research Group, Department of Ophthalmology, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany. METHODS: In a standardized laboratory setup, the Miyake-Apple posterior view video technique was used to evaluate OVD removal from capsular bags in human autopsy eyes implanted with poly(methyl methacrylate) (PMMA), silicone, and acrylic IOLs. The cohesive OVD ProVisc (sodium hyaluronate 1.0%) and the dispersive OVD Viscoat (sodium hyaluronate 3.0% and chondroitin sulfate 4.0%) were stained with fluorescein for better visualization. The open-sky preparation and an Alcon Series 20000 Legacy phaco machine with a flow rate of 25 mL/min and a vacuum setting of +500 mm Hg (maximum irrigation/aspiration) were used. The time needed for complete removal of the cohesive and dispersive OVDs with each IOL type was measured and analyzed statistically. RESULTS: The mean removal times for both OVDs were as follows: Alcon MZ60BD PMMA IOL-25.0 seconds +/- 3.7 (SD) (Viscoat), 15.9 +/- 6.9 seconds (ProVisc); Alcon AcrySof MA60BM IOL-35.5 +/- 10.0 seconds (Viscoat), 25.6 +/- 4.7 seconds (ProVisc); Chiron/Bausch & Lomb C1043 silicone IOL-46.5 +/- 10.5 seconds (Viscoat), 17.3 +/- 2.1 seconds (ProVisc); AMO SI-30 silicone IOL-33.5 +/- 3.1 seconds (Viscoat), 15.3 +/- 6.3 seconds (ProVisc); and Pharmacia 912 silicone IOL-18.3 +/- 5.8 seconds (Viscoat), 19.8 +/- 4.3 seconds (ProVisc). CONCLUSIONS: Differences in OVD removal times were detected. The removal time for the cohesive OVD correlated with the IOL material. Overall, the time needed for complete removal was significantly longer for the dispersive OVD than for the cohesive OVD.     

Retention and removal of a new viscous dispersive ophthalmic viscosurgical device during cataract surgery in animal eyes

AIMS: To assess the retention and removal properties of a new viscous dispersive ophthalmic viscosurgical device (OVD), DisCoVisc, in comparison with those of cohesive (Provisc), dispersive (Viscoat), and viscoadaptive (Healon5) OVDs. METHODS: In 20 porcine eyes, cataract surgery was simulated using one of the four OVDs which were stained with fluorescein for better visualisation. Three parameters were measured. Firstly, the presence/absence of OVDs in the chamber at the completion of phacoemulsification was recorded. Secondly, the time until the OVDs were completely removed from the anterior chamber using the phaco needle was measured. Thirdly, after intraocular lens (IOL) implantation, the time needed to completely remove the OVDs from the chamber with irrigation/aspiration tip was recorded. RESULTS: At the completion of phacoemulsification, the OVDs retained in 0% (0/5) for Provisc, 80% (4/5) for Healon5, 100% (5/5) for DisCoVisc, and 100% (5/5) for Viscoat. The retention of OVDs during phacoemulsification was greatest with Viscoat followed by, in descending order, DisCoVisc, Healon5, and Provisc. The removal of OVDs after IOL implantation took longest with Viscoat followed by Healon5, DisCoVisc, and Provisc. CONCLUSION: The viscous dispersive DisCoVisc showed excellent retention during phacoemulsification, while its removal after IOL implantation was very easy. When compared with the viscoadaptive Healon5, DisCoVisc was retained better in the chamber and was easier to remove. These features of DisCoVisc should be highly advantageous when considering covering the entire cataract surgery procedure with a single OVD.     

Effect of a fixed dorzolamide-timolol combination on intraocular pressure after small-incision cataract surgery with Viscoat

PURPOSE: To evaluate the effect of a fixed dorzolamide-timolol combination (Cosopt) on intraocular pressure (IOP) after small-incision cataract surgery with sodium chondroitin sulfate 4%-sodium hyaluronate 3% (Viscoat). SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria. METHODS: This prospective randomized study comprised 76 eyes of 38 patients scheduled for small-incision cataract surgery in both eyes. Patients were randomized to receive 1 drop of the fixed dorzolamide-timolol combination in 1 eye or no treatment (control) immediately after cataract surgery. The fellow eye received the other assigned treatment. Cataract surgery was performed with Viscoat in an identical fashion in both eyes. The IOP was measured preoperatively and 6 hours, 20 to 24 hours, and 1 week postoperatively. RESULTS: Six hours after surgery, the mean increase in IOP was significantly lower in the dorzolamide-timolol group than in the control group (4.3 mm Hg +/- 5.6 [SD] versus 8.4 +/- 6.1 mm Hg; P =.003). Two eyes in the dorzolamide-timolol group and 9 in the control group had IOP spikes of 30 mm Hg or higher (P =.022). Twenty to 24 hours after surgery, the mean IOP change was -2.6 +/- 3.3 mm Hg in the dorzolamide-timolol group and 1.5 +/- 3.2 mm Hg in the control group (P<.001). CONCLUSIONS: The fixed dorzolamide-timolol combination was effective in reducing IOP 6 hours and 20 to 24 hours after cataract surgery. However, it did not prevent Viscoat-induced IOP spikes of 30 mm Hg or higher.     

Hydroxyl radical scavenging activity of a new ophthalmic viscosurgical device

PURPOSE: To quantify the hydroxyl radical scavenging activity of a new ophthalmic viscosurgical device (OVD) based on sodium hyaluronate and hydroxypropylmethylcellulose (named VISC28) in comparison with Viscoat, Healon, and Amvisc Plus. METHODS: The hydroxyl radicals that represent the principal free-radical species generated during phacoemulsification were produced by the Fenton reaction, and the scavenging activity of the tested viscoelastic substances was evaluated in vitro by the 2-deoxy-D-ribose (2-DR) oxidation method that produces the thiobarbituric acid-malondialdehyde (TBA-MDA), complex. An aliquot of viscosurgical formulation was added to phosphate buffer and mixed with 2-DR, Fe2 +/ethylenediaminetetraacetic acid (EDTA), and H2O2. The sample mix was incubated and thiobarbituric acid-trichloroacetic acid solution was added. The sample was then incubated for 30 min, and a chromatographic analysis was performed to quantify the TBA-MDA complex. The data were expressed as micromoles of MDA per milliliter of sample. RESULTS: All tested OVDs showed a marked hydroxyl radical scavenging activity. The MDA level was significantly lower in VISC28 (0.045 +/- 0.007 micromol/ml) compared with Viscoat (0.070 +/- 0.012 micromol/ ml, p < 0.05), Amvisc Plus (0.111 +/- 0.008 micromol/ml, p < 0.001), and Healon (0.175 +/- 0.016 micromol/ml, p < 0.001). A reduced scavenging activity was shown by VISC28 phosphate-buffered solution (PBS) (no TRIS and no sorbitol) compared with VISC28 (p < 0.001). CONCLUSIONS: The new OVD, VISC28, showed significantly higher hydroxyl radical inhibition compared with the other viscosurgical formulations. The following rank order for the scavenging activity was established: VISC28 > Viscoat > Amvisc Plus > Healon.     

Spontaneously resolving descemet’s membrane detachment caused by an ophthalmic viscosurgical device during cataract surgery

We present a case of a central Descemet’s membrane detachment (DMD) induced by an Ophthalmic Viscosurgical Device during phacoemulsification surgery that resolved spontaneously, leaving a best spectacle corrected visual acuity of 20/20. The detachment was monitored with serial anterior segment optical coherence tomography images. Most cases of central DMD reported in the literature have been managed surgically to facilitate rapid visual recovery and minimize the risk of scarring. Our case adds to the literature in providing an alternative management strategy where surgical intervention may not be possible.     

Scheimpflug photography study of ophthalmic viscosurgical devices during simulated cataract surgery

PURPOSE: To evaluate by Scheimpflug photography the capacity of several commercially available ophthalmic viscosurgical devices (OVDs) to remain in the anterior chamber and maintain anterior chamber depth (ACD) during simulated cataract surgery in porcine cadaver eyes. SETTING: Department of Preclinical Ophthalmology, Pharmacia & Upjohn AB, Uppsala, Sweden. METHODS: Eighty eyes from newly slaughtered pigs were used. They were distributed equally among 8 OVDs: Amvisc Plus (sodium hyaluronate 1.6%), Biolon (sodium hyaluronate 1.0%), Biolon Prime (sodium hyaluronate 1.2%), Healon (sodium hyaluronate 1.0%), Healon GV (sodium hyaluronate 1.4%), Healon5 (sodium hyaluronate 2.3%), Provisc (sodium hyaluronate 1.0%), and Viscoat (sodium hyaluronate 3.0%-chondroitin sulfate 4.0%). Scheimpflug photographs were taken using a Nidek EAS-1000 instrument before surgery (control), after injection of the OVD, after continuous curvilinear capsulorhexis (CCC), and after lens extraction by phacoemulsification. Differences in the ACD with a P value less than 0.05 were considered statistically significant. The retention capacity was visually assessed. RESULTS: Healon5 had a significantly higher capacity to maintain the ACD than the other OVDs after CCC and phacoemulsification. After injection, Healon5, Viscoat, and Biolon Prime showed similar ACD-maintaining capacities. CONCLUSIONS: The capacity of Healon5 to maintain the ACD during cataract surgery, ie, neutralizing the vitreous pressure and stabilizing the anterior segment of the eye, was significantly higher than that of the other OVDs.     

小切口非超声乳化白内障手术后角膜曲率变化的分析

目的：测量小切口非超声乳化白内障手术后角膜曲率的变化,探讨手术源性角膜散光的特点。 方法：分别测量小切口非超声乳化白内障手术患者99例116眼的术前、术后3 d;1,2 wk;1,3,6 mo;1,2,3 a的角膜水平曲率（ horizontal corneal curvature, HCC）和垂直曲率值（ vertical corneal curvature,VCC）,求出HCC和VCC的术后相对于术前的差值。用统计软件对术后HCC差值和VCC差值进行统计分析。 结果：术后3d,VCC减少2.01D,HCC增大1.62D,两者之间有显著差异（ P〈0.001）;术后3 mo内HCC和VCC差值均迅速减小,3mo时VCC差值-0.52D,HCC差值0.46D;3 mo后VCC和HCC差值均缓慢减少,6 mo时VCC差值-0.29D,HCC差值0.29D,两者之间无显著差异（ P=0.801）;术后3a,VCC仍较术前小（-0.26D）,HCC较术前大（0.25D）。术后各时间点的角膜曲率差值进行配对t检验：术后3d至术后6mo的时间内,VCC和HCC均明显减小（P〈0.001）,术后6mo 到3a 之间 VCC（P=0.284）和HCC（P =1.000）无明显改变。 结论：小切口白内障手术术后短期角膜散光较大,手术方式需进一步改进以减少散光。     

Comparison of the effect of Viscoat and DuoVisc on postoperative intraocular pressure after small-incision cataract surgery

PURPOSE: To evaluate the effect of Viscoat (sodium chondroitin sulfate 4%-sodium hyaluronate 3%) and DuoVisc (Viscoat and Provisc [sodium hyaluronate 1%]) on postoperative intraocular pressure (IOP) after bilateral small-incision cataract surgery. SETTING: Department of Ophthalmology, University of Vienna, Vienna, Austria. METHODS: This prospective randomized study comprised 60 eyes of 30 consecutive patients with age-related cataract in both eyes. Each patient's eyes were randomly assigned to receive Viscoat or DuoVisc during cataract surgery. DuoVisc is a packet containing 2 ophthalmic viscosurgical devices (OVDs): the dispersive Viscoat, which was used for intraocular lens (IOL) implantation. In the Viscoat group, the Viscoat was used during the entire surgery. The intraocular pressure (IOP) was measured preoperatively as well as 1, 6, and 20 to 24 hours postoperatively. RESULTS: One and 6 hours postoperatively, the mean IOP was significantly higher in the Viscoat group than in the DuoVisc group (25.8 mm Hg and 20.5 mm Hg, respectively, at 1 hour and 24.7 mm Hg and 21.1 mm Hg, respectively, at 6 hours) (P<.05). At 20 to 24 hours, the mean IOP was not statistically significantly different between the 2 groups. Intraocular pressure spikes to 30 mm Hg or higher occurred in 4 eyes in the DuoVisc group and 11 eyes in the Viscoat group (P<.05). CONCLUSIONS: Viscoat caused significantly higher IOP increases and significantly more IOP spikes than DuoVisc in the early postoperative period. Therefore, if Viscoat is used during cataract surgery, an additional cohesive OVD should be used for IOL implantation.     

Effect of incisional friction and ophthalmic viscosurgical devices on the heat generation of ultrasound during cataract surgery

PURPOSE: To determine the thermal features of the Legacy (Alcon) and Sovereign (Advanced Medical Optics) phacoemulsification machines in a cadaver eye and with 7 ophthalmic viscosurgical devices (OVDs). SETTING: In situ and in vitro study. METHODS: Temperature without occlusion was recorded at the sleeve placed in the wound of a cadaver eye, and temperature over baseline was determined after 60 seconds. The result was then compared with the results in a previous study that used balanced salt solution (BSS) in artificial chambers. In the second portion of the experiment, with irrigation and aspiration lines occluded, temperature was recorded at the sleeve placed in an artificial chamber filled with sodium hyaluronate 2.3% (Healon5), sodium hyaluronate 1.4% (Healon GV), sodium hyaluronate 1.0% (Healon), sodium hyaluronate 1.6% (Amvisc Plus), sodium hyaluronate 1.0% (Provisc), sodium hyaluronate 3.0%-chondroitin sulfate 4.0% (Viscoat), or hyaluronate 3.0% (Vitrax). Temperature over baseline was also determined after 60 seconds. These results were compared with each set of OVD data and with the results in the prior BSS study. RESULTS: In the eye-bank model, the Legacy machine had a 62% temperature increase from incisional friction and the Sovereign machine had a decrease of 8.6% over results in an artificial anterior chamber. The OVD temperature increases were greater for the Sovereign (P<.001) and followed the same general trend for the Legacy. The least temperature increase was with Amvisc Plus, Healon, and Healon GV; the intermediate increases were with Provisc and Vitrax; and the greatest increases were with Viscoat and Healon5. The OVD findings did not correlate with viscosity or pseudoplasticity. CONCLUSIONS: Incisional friction alone increased heat generation in the Legacy, a stroke-length driven instrument, more than in the Sovereign, a power-driven instrument. Ophthalmic viscosurgical devices are not only a concern due to outflow occlusion but can also add up to 6 times the heat in comparison with BSS. The need to aspirate the OVD before using ultrasound is thus verified.     

白内障术毕结膜囊应用黏弹剂对患者术后早期干眼的预防效果

目的　探讨白内障术毕结膜囊应用黏弹剂对患者术后早期干眼的预防效果。方法　本研究为前瞻性随机对照研究。随机选取2020年6月至2021年2月在北京大学国际医院眼科行超声乳化白内障吸除联合人工晶状体植入术的年龄相关性白内障患者95例（114眼）。采用随机数字表法将患者分为黏弹剂组48例（58眼）和对照组47例（56眼）。术毕,黏弹剂组患者结膜囊内滴入黏弹剂,对照组患者结膜囊内滴入平衡盐溶液。术前1周,术后1 d、7 d、30 d依次记录和检测患者主观眼表疾病指数(OSDI)量表评分、泪膜破裂时间（BUT）、眼表染色评分（OSS）、Schirmer I 试验值（SIt）。对记录和检测的两组患者各项指标进行统计分析。结果　术前两组患者OSDI评分、BUT、角膜与结膜OSS及SIt比较差异均无统计学意义（均为P>0.05）。术后1 d、7 d、30 d两组患者OSDI评分均较术前提高,差异均有统计学意义（均为P<0.05）。术后1 d及30 d,黏弹剂组OSDI评分均低于对照组,差异均有统计学意义（均为P<0.05）。黏弹剂组患者术后1 d及7 d BUT较术前升高,对照组术后1 d BUT较术前降低,差异均有统计学意义（均为P<0.05）。术后1 d及7 d,黏弹剂组患者BUT均高于对照组,差异均有统计学意义（均为P<0.05）。对照组患者角膜OSS在术后1 d、7 d及30 d均高于术前,结膜OSS在术后1 d高于术前;黏弹剂组患者仅角膜OSS在术后1 d高于术前,差异均有统计学意义（均为P<0.05）。术后1 d、7 d及30 d黏弹剂组患者角膜OSS均低于对照组,术后1 d结膜OSS低于对照组,差异均有统计学意义（均为P<0.05）。术后1 d黏弹剂组患者SIt低于对照组,差异有统计学意义（P<0.05）。结论　白内障术毕结膜囊应用黏弹剂可以有效减轻患者术后早期干眼症状和体征。     

Effect of bimatoprost on intraocular pressure after cataract surgery

Background: An increase in intraocular pressure (IOP) frequently occurs after otherwise uneventful phacoemulsification cataract surgery. This study was conducted to determine the efficacy of bimatoprost 0.03% drops given preoperatively in preventing IOP rise following phacoemulsification cataract surgery.Methods: In this prospective, randomized, double-masked, placebo-controlled study, 91 eyes of 85 patients scheduled to have clear corneal phacoemulsification cataract surgery were randomly divided into 2 groups. One hour before surgery, 1 group (48 eyes) received 1 drop of bimatoprost 0.03%, and the other group (43 eyes) received 1 drop of a balanced saline solution (placebo). A masked observer measured IOP preoperatively, and 3 and 24 hours postoperatively. Anterior chamber cellular reaction was measured on the first day after surgery. Preoperative and postoperative central corneal thickness (CCT) was assessed.Results: The mean IOP changes from baseline were not statistically different between the 2 groups at 3 hours (p = 0.618). At 24 hours, there was a statistically significant difference between the mean IOP changes of the groups (p = 0.001). The incidence of IOP elevation greater than 5 or 10 mm Hg at 24 hours was significantly higher in the control group (9 of 43 eyes) than the bimatoprost group (3 of 48 eyes) (p = 0.039). Anterior chamber reaction was not increased by bimatoprost. Mean CCT change was not different between the groups at 24 hours (p = 0.615).Interpretation: When compared with placebo, prophylactic use of 1 drop of bimatoprost before phacoemulsification cataract surgery failed to produce a significantly different effect on IOP levels from placebo at 3 hours postoperatively, but it caused a significant IOP reduction at 24 hours.     

Astigmatism after small-incision clear corneal cataract extraction and intraocular lens implantation in children

PURPOSE: To investigate the magnitude of postoperative astigmatism in children having cataract extraction with intraocular lens (IOL) implantation through a 3.0 mm superior clear corneal incision. SETTING: Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, USA. METHODS: This retrospective chart review comprised all pediatric patients having cataract surgery with IOL implantation through a 3.0 mm clear corneal incision from 1997 to 2002. One hundred two eyes of 75 patients were included. All refractions were performed manually by an experienced pediatric ophthalmologist. RESULTS: The mean postoperative retinoscopic cylinder in all patients was 0.63 diopter (D) (range 0.0 to 4.50 D) at 1 month, 0.40 D (range 0.0 to 1.75 D) at 6 months, and 0.51 D (range 0.0 to 2.50 D) at 1 year. Patients aged 0 to 36 months at the time of surgery had a mean postoperative cylinder of 0.22 D at 1 month, 0.03 D at 6 months, and 0.21 D at 1 year. Patients between 36 months and 6 years of age at surgery had a mean refractive cylinder of 0.50 D, 0.38 D, and 0.75 D, respectively. Patients older than 6 years at surgery had a mean refractive cylinder of 0.94 D, 0.75 D, and 0.76 D, respectively. CONCLUSIONS: Small-incision clear corneal cataract extraction with IOL implantation in children led to minimal postoperative astigmatism that remained stable over time. Less astigmatism was observed in children having surgery before they were 36 months old.     

Influence of corneal diameter on surgically induced astigmatism in small-incision cataract surgery

ObjectiveClear corneal incisions (CCI) in cataract surgery create a variable amount of surgically induced astigmatism (SIA). As refractive outcomes become increasingly important, it is necessary to understand factors that impact SIA and refractive surprises. In this study, we evaluate the effect of horizontal corneal diameter (white-to-white, WTW) on SIA in 2.2 mm small-incision cataract surgery.DesignProspective study at an academic-university-based outpatient clinic (Duke Eye Center).ParticipantsWe enrolled adults ≥18 years of age without prior corneal surgery or corneal pathology undergoing cataract surgery with a single surgeon (R.R.V.).MethodsAll surgeries were uncomplicated and performed through a manually constructed, limbal, temporal, or superotemporal 2.2 mm CCI. Enrolled participants received standard-of-care evaluations and postoperative management. SIA was calculated at the first postoperative month using the Jaffe and Clayman vector analysis equation.ResultsWe enrolled 43 subjects (55 eyes) with a mean age of 71 years with WTW corneal diameter values ranging from 11.34 to 12.99 mm obtained from Lenstar® (Haag-Streit Group, Koeniz, Switzerland). Postoperative SIA ranged from 0.072 to 1.6 D (mean 0.47 D, standard deviation 0.33 D). SIA was plotted against WTW and best fit to a linear regression model with a slope of −0.056 and an R² value of 0.006.ConclusionsIn this prospective study, WTW diameter had minimal effects on the SIA in uncomplicated small-incisional cataract surgery through a 2.2 mm temporal or superotemporal CCI with a single surgeon. Our findings suggest that corneal diameter does not play a clinically significant role in this population undergoing small-incisional cataract surgery.     

Removal times and techniques of a viscoadaptive ophthalmic viscosurgical device

PURPOSE: To analyze removal techniques for Healon5 (sodium hyaluronate 2.3%). SETTING: Center for Research on Ocular Therapeutics and Biodevices, Charleston, South Carolina, USA, and Department of Ophthalmology, Ruprecht-Karls-University, Heidelberg, Germany. METHODS: In a standardized laboratory setup, the Miyake-Apple posterior view video technique in human autopsy eyes was used to evaluate removal of an ophthalmic viscosurgical device (OVD) from capsular bags implanted with poly(methyl methacrylate), silicone, and acrylic intraocular lenses (IOLs). Healon5 was stained with fluorescein for better visualization. Open-sky preparation and an Alcon Legacy Series 20000 phaco machine with a flow rate of 25 mL/minute and a vacuum setting of +500 mm Hg (maximum irrigation/aspiration [I/A]) were used. With Technique 1, the I/A tip was placed on the center of the IOL and maximum aspiration was applied. With Technique 2 (modified rock 'n roll technique), the I/A tip was moved in quick circular movements on top of the IOL to break the OVD chains and facilitate aspiration. RESULTS: With Technique 1, the mean removal time was 59.0 seconds +/- 23.1 (SD) and with Technique 2, 23.6 +/- 10.3 seconds (P =.004). The removal time of Healon5 correlated with the IOL material. With Technique 2, removal was fastest with silicone IOLs (13.5 +/- 2.1 seconds) followed by PMMA IOLs (17.5 +/- 2.1 seconds). With acrylic IOLs, remnants of the OVD trapped behind the IOL optic resulted in a longer removal time of 34.1 +/- 1.2 seconds. CONCLUSIONS: Healon5 was completely removed from the capsular bag with the modified rock 'n roll technique. With acrylic IOLs, remnants can be trapped behind the optic and may be overlooked with an unstained OVD. Aspiration behind the optic is recommended with this IOL type.     

小切口白内障摘出术和超声乳化白内障摘出术对角膜规则性的影响

背景 白内障手术诱发干眼的发病机制除切口对角膜神经纤维的影响外,可能还与手术改变角膜的规则性有关. 目的 探讨手法小切口白内障摘出术与超声乳化白内障摘出术后角膜前表面规则性改变及泪膜和角膜散光的动态变化.方法 采用前瞻性非随机病例对照研究设计.收集46例50眼年龄相关性白内障患者,其中30例30眼行小切口白内障摘出术,16例20眼行超声乳化白内障摘出术.于术前及术后1d、1周、1个月行角膜地形图检查,测量角膜不规则指数(CIM)、形状系数(SF)和散光值,对患者主观感觉进行评分,于术前及术后1周、1个月测量泪膜稳定性值、泪膜破裂时间(BUT)与基础泪液分泌试验Ⅰ(SⅠt)值;分别行各组内、两组间参数比较.结果 两组术眼CIM值随着手术前后时间的不同发生变化,术后CIM值均明显高于手术前,总体比较差异有统计学意义(F时间=22.864,P=0.000),其中术后1d、1周、1个月两组术眼CIM值明显高于术前,差异均有统计学意义(P＜0.01);不同时间点两组间术眼CIM值比较差异无统计学意义(F分组=0.062,P=0.804).两组术前及术后不同时间点、两组间SF比较差异均无统计学意义(F时间=4.600,P=0.428;F分组 =0.009,P=0.925).两组术眼随着术后时间的延长,BUT值逐渐降低,差异有统计学意义(F时间=39.384,P=0.000),术后1周、1个月各组BUT值较术前降低,差异均有统计学意义(均P=0.000),但各时间点两组间术眼BUT值的比较差异无统计学意义(F分组=0.000,P=0.983).小切口组术眼手术后1周、1个月SⅠt值与术前比较差异均有统计学意义(P＜0.01).两组术后1d、1周、1个月均存在手术源性散光(SIA),但随时间的推移,两组SIA值逐渐减小,差异有统计学意义(F时间=21.479,P=0.000),不同时间点两组间的SIA值比较差异有统计学意义(F分组=8.709,P=0.005);其中术后各时间点超声乳化白内障摘出术组SIA值均明显低于小切口组,差异均有统计学意义(P＜0.01). 结论 小切口白内障摘出术和超声乳化白内障摘出术术后早期,角膜前表面不规则性增加,泪膜稳定性下降,均可产生SIA.