Amount Of Balanced Salt Solution Research Articles

Quantitative Assessment of Ophthalmic Viscosurgical Devices on Visibility, Spreadability, and Durability as Corneal Wetting Agents for the Wet Shell Technique.

PurposeTo evaluate ophthalmic viscosurgical devices (OVDs) as corneal wetting agents for the wet shell technique, a common procedure in Japan to maintain the wettability of corneal surfaces.MethodsWe surveyed Japanese ophthalmologists to determine the current state of the wet shell technique. After developing three ex vivo testing methods, we evaluated the corneal wetting properties of OVDs including 3% hyaluronic acid (HA) solution and OVD products, Opegan, Opelead, Viscoat, Shellgan, Discovisc, and Opegan-Hi.ResultsOverall, 214 ophthalmologists (70%) had performed the wet shell technique, and 91% of ophthalmologists who performed vitreous surgery had performed this technique. Using a questionnaire, we evaluated the performance of OVD as corneal wetting agents as follows: (i) visibility, smoothness of OVD surface; (ii) spreadability, coverage of the cornea; and (iii) retention durability, residual ratio of OVD on the corneal surface. The smoothness and spreadability of Opegan, Opelead, and 3% HA were superior to other OVDs. Adding an appropriate amount of balanced salt solution to the other OVDs improved smoothness and spreadability similar to that of Opelead or 3% HA. Shellgan and Viscoat, combination OVDs consisting of 3% HA and 4% chondroitin sulfate, showed high retention durability, resulting in remaining longer on the cornea compared with other OVDs.ConclusionsPhysical properties of OVDs tested in this study may provide useful information for ophthalmologists to select a suitable OVD when performing the wet shell technique.

Multiquadrant versus single quadrant cortical cleaving hydrodissection during phacoemulsification of age related cataract

PurposeTo evaluate and compare single and multiquadrant hydrodissection in age related cataract. DesignProspective, observational case series. MethodsIn this study, 220 patients were consecutively assigned to either single (n = 110) or multiquadrant (n = 110) hydrodissection during phacoemulsification. Patients having operable cataract in the nuclear grade of 1–3 of Lens Opacities Classification System III were included in the study. After hydrodissection of the nucleus nuclei were not rotated. Parameters assessed were amount of balanced salt solution (BSS) required to accomplish the hydrodissection, nucleus emulsification time (NET), and cortical aspiration time (CAT). Ease in nucleus rotation during chopping of the nucleus, cortical aspiration (easy, difficult, or very difficult) and intraoperative surgical complications were qualitatively assessed. ResultsAverage amount of BSS required in multiquadrant hydrodissection was 1.7 ml (±0.9), which was more than double the single quadrant group 0.71(±0.17), p = 0.001. No statistically significant differences were observed between the two studied groups with respect to the following parameters: mean NET (single quadrant 277 sec ± 95.5, multiquadrant 267 sec ± 98.8, p = 0.379), CAT (single quadrant 75.7 sec ± 31.2, multiquadrant 73.4sec ± 33.9p = 0.301), and total fluid required (single quadrant 154 ml ± 64.9, multiquadrant 157 ml ± 66.4p = 0.708).Almost equal number of patients in both the groups had easy rotation of the nucleus (single quadrant: n = 105, 95.45% and multiquadrant n = 103, 93.64%) and cortical aspiration (n = 102, 92.72% both the groups). Three patients in multiquadrant group had posterior capsular rupture during hydrodissection. ConclusionsA single quadrant hydrodissection is sufficient for the efficient removal of nucleus and cortex.

Evaluation of the Protective Effect of an Ophthalmic Viscosurgical Device on the Ocular Surface in Dry Eye Patients during Cataract Surgery.

PurposeTo evaluate the protective effect of applying an ophthalmic viscosurgical device (OVD) to the ocular surface during cataract surgery and its ability to prevent dry eye syndrome.MethodsTwenty-four patients aged 50 to 75 years who underwent cataract surgery at Seoul National University Bundang Hospital and agreed to participate in the study were included and divided into two groups: a study group who underwent cataract surgery after application of an OVD to the ocular surface, and a control group who underwent cataract surgery without application of an OVD. DisCoVisc was used as the OVD in the study group, while other factors including surgical techniques and administration of anesthetic agents were performed in both groups in the same manner. Indicators of dry eye syndrome including ocular staining score, tear break-up time, and tear osmolality were analyzed. Ocular surface disease index and a visual analog scale were analyzed for dry eye symptoms, and the amount of balanced salt solution used during surface irrigation and operation time were also analyzed.ResultsSignificant improvement in the tear break-up time, corneal ocular staining score, and ocular surface disease index score in the study group compared with the control group one week after operation (by the Mann-Whitney test). Use of OVD was associated with longer operating time.ConclusionsOVD applied to the ocular surface during cataract surgery had a protective effect on the ocular surface one week after surgery.

Impact of low versus high fluidic settings on the efficacy and safety of phacoemulsification

To compare intraoperative efficiency and postoperative outcomes of cataract surgery with low and high fluidic settings. In this prospective, randomized, single-blinded study, 114 eyes of 57 patients were operated with low fluidic settings for one eye (group I) and high fluidic settings for the other eye (group II). Efficiency was judged as metred surgery time, effective phacoemulsification time (EPT) and the amount of balanced salt solution used. Visual outcome and endothelial cell count were determined 1 week and 18 months postoperatively. The overall effective phacoemulsification energy was statistically significantly lower (p = 0.003) in group II than in group I. Conquest of the nuclei was achieved with about two-thirds of the energy needed in group I, with 6.59 ± 4.79 effective ultrasound energy compared with 3.99 ± 3.18 (p = 0.001). Overall, about 12% more solution was used in group II than in group I. Median visual acuity was 1.0 for both groups 18 months after surgery. The mean endothelial cell loss was 5.0% in eyes in group I compared with 6.3% in eyes in group II (p > 0.5). Switching from low fluidic settings with a conventional coaxial 20G phacoemulsification tip to higher fluidic settings with a microcoaxial phaco tip statistically significantly decreases EPT. As only marginally more solution was used with the higher aspiration flow, occlusion must be accomplished more often with high than with low fluidics. Aspiration of the quadrants was therefore more efficient with high fluidic settings. The enhanced pump speed did not result in more tissue damage.

Feasibility of the New Torsional Phacoemulsification Software Phacoemulsification (Ozil IP) in Hard Cataracts.

To assess the feasibility of using the new torsional intelligent phacoemulsification software (Ozil IP) phacoemulsification in hard cataracts of N3+. A cohort study. Eighty patients were recruited and randomized into 2 groups, the study group and the control group. Each group consisted of 40 eyes. Routine cataract surgeries were performed using standard torsional software (Ozil) and Ozil IP in hard cataracts of N3+. Main outcome measures included cumulative dissipated energy (CDE), amount of balanced salt solution (BSS) used, and changes in central corneal thickness (CCT). The mean CDE was significantly less in the study group compared with the control group (P = 0.05). The mean time in foot pedal position 3 (FP3) for varying grades of cataract density ranged from 16.3 to 30.2 seconds in the study group and from 19.1 to 39.7 seconds in the control group, which was statistically significant (P = 0.03). The amount of BSS used was 34.19 mL in the study group and 44.05 mL in the control group. On the first postoperative day, CCT was significantly different between the study and the control group (P = 0.005). The 3 parameters (CDE, FP3 and BSS amount) were found to be effective with no significant complications. The new Ozil IP required less CDE and less FP3 time with less postoperative corneal edema, and thus patients had a more rapid visual recovery.

Evaluation of the analgesic effect of intracameral lidocaine hydrochloride injection on intraoperative and postoperative pain in healthy dogs undergoing phacoemulsification

To evaluate the intraoperative and postoperative analgesic effects of intracameral lidocaine hydrochloride injection in dogs undergoing phacoemulsification. 12 healthy Beagles with healthy eyes. Dogs were randomly assigned to receive 1 of 2 intracameral injections: 2% lidocaine hydrochloride solution (0.3 mL) or an equivalent amount of balanced salt solution (BSS). All dogs were treated with acepromazine (0.05 mg/kg, i.v.) and cefazolin (30 mg/kg, i.v.), and tropicamide drops were topically applied to the eyes. Anesthesia was induced with propofol and maintained with isoflurane. The initial end-tidal isoflurane concentration was maintained at 1.2%. Heart rate, respiratory rate, arterial blood pressure, esophageal temperature, inspired and end-tidal isoflurane concentrations, and oxygen saturation were recorded every 5 minutes. The allocated agent was injected intracamerally after aspiration of the same volume of aqueous humor. Ten minutes after injection, phacoemulsification was performed. After surgery began, the isoflurane concentration was adjusted according to heart rate and mean arterial blood pressure. Pain scores were recorded before surgery and at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 6, 8, 16, and 24 hours after extubation. Isoflurane requirements were significantly higher in the BSS group than in the lidocaine group. Mean +/- SD time to administration of supplementary analgesia was significantly shorter in the BSS group (1.4 +/- 1.2 hours) than in the lidocaine group (4.9 +/- 1.2 hours). Intracameral lidocaine injection had significant analgesic effects in dogs undergoing cataract surgery. Results of this study suggest the value of intracameral lidocaine injection as an analgesic for intraocular surgery in dogs.

Microcoaxial cataract surgery outcomes: Comparison of 1.8 mm system and 2.2 mm system

To compare clinical outcomes of a 1.8 mm and a 2.2 mm microcoaxial cataract surgery system. Department of Ophthalmology and Visual Science, Kangnam St. Mary's Hospital, College of Medicine, Catholic University of Korea, Seoul, Korea. In a prospective study, eyes were randomly selected to have phacoemulsification using a Stellaris system or an Intrepid Infiniti system. The initial incision size was 1.8 mm and 2.2 mm, respectively. Measured intraoperative parameters included phacoemulsification time, mean cumulative dissipated ultrasound energy (CDE), change in incision size at each step of surgery, and total volume of balanced salt solution (BSS) used. The best corrected visual acuity (BCVA), corneal astigmatism, corneal thickness, and endothelial cell count were evaluated preoperatively and postoperatively. The study evaluated 86 eyes of 78 patients (43 eyes in each group). There were no significant differences in postoperative BCVA, surgically induced astigmatism, or amount of BSS used between the 2 systems (P >.05). However, for high-density cataracts, the 1.8 mm group had a greater change between the initial incision size and the incision size after phacoemulsification (P = .019, nuclear opalescence [NO] NO3; P = .001, NO4), a longer phacoemulsification time (P = .013, NO3), greater mean CDE (P = .005, NO3; P = .001, NO4), and greater corneal endothelial cell loss (P = .003, NO4). Both systems were safe and effective in microcoaxial phacoemulsification. The 1.8 mm system performed better with cortical-type cataract and the 2.2 mm system, with high-density nuclear-type cataract.

Comparison of the Infiniti Vision and the Series 20,000 Legacy Systems

Purpose: To compare the efficiency of the Infiniti vision system and the Series 20,000 Legacy system phacoemulsification units during routine cataract extraction. Methods: Thirty-nine eyes of 39 patients were randomized to have their cataract removed using either the Infiniti or the Legacy system, both using the Neosonix handpiece. System settings were standardized. Ultrasound time, amount of balanced salt solution (BSS) used intraoperatively, and postoperative visual acuity at postoperative days 1, 7 and 30 were evaluated. Results: Preoperatively, best corrected visual acuity was significantly worse in the Infiniti group compared to the Legacy group (0.38 ± 0.23 and 0.21 ± 0.16, respectively; p = 0.012). The mean phacoemulsification time was 39.6 ± 22.9 s (range 6.0–102.0) for the Legacy group and 18.3 ±19.1 s (range 1.0–80.0) for the Infiniti group (p = 0.001). The mean amounts of intraoperative BSS used were 117 ± 37.7 ml (range 70–195) in the Legacy group and 85.3 ± 38.9 ml (range 40–200) in the Infiniti group (p = 0.005). No differences in postoperative visual acuity were found. Conclusion: The ability to use higher flow rates and vacuum settings with the Infiniti vision system allowed for cataract removal with less phacoemulsification time than when using the Legacy system.

Increased retinal toxicity of intravitreal tissue plasminogen activator in a central retinal vein occlusion model

Intravitreal injection of tissue plasminogen activator (tPA) is used to treat several ocular conditions, although excessive doses of intravitreal tPA cause retinal toxicity. Toxicity may increase in the ischemic retina, such as in central retinal vein occlusion (CRVO), because tPA toxicity to neural tissues increases under ischemic conditions. We investigated tPA toxicity to the retina in a CRVO rat model. CRVO was induced in pigmented rats with rose Bengal-assisted laser photothrombosis. One hour after CRVO induction, 3 microl of tPA (0.075, 0.75, 3, or 7.5 microg) was injected intravitreally. Eyes that did not receive laser treatment, which served as non-CRVO controls, received tPA (0.75, 3, or 7.5 microg). The same amount of balanced salt solution (BSS) was injected as a nondrug control. Eyes were enucleated at 12 hours after injection, and terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) staining was performed to evaluate retinal cell apoptosis. The number of TUNEL-positive cells increased in a dose-dependent manner in both non-CRVO and CRVO group and significantly (P = 0.002) increased when 0.75, 3, or 7.5 microg of tPA was injected into the CRVO eyes. When comparing the number of TUNEL-positive cells between the eyes with and without CRVO that received the same treatment, apoptosis significantly increased in CRVO eyes. Retinal toxicity associated with intravitreally injected tPA can increase in a dose-dependent manner and be exacerbated in CRVO eyes, suggesting that the dose of tPA should be reduced when tPA is used to treat eyes with CRVO.

Exfoliation Syndrome as a Risk Factor for Corneal Endothelial Cell Loss in Cataract Surgery

To compare the influence of various cataract surgery pre-, intra-, and postoperative characteristics to cornea endothelium and thickness in patients with and without exfoliation syndrome (PEX). In this prospective study 27 consecutive patients with and 26 patients without PEX as a control group scheduled for cataract surgery were studied. The corneal endothelial cells were evaluated preoperatively and postoperatively at 1 day and 1 month after surgery using noncontact specular microscopy. Intraoperative parameters of operation time, phacoemulsification (phaco) time, phaco power and amount of balanced salt solution (BSS) were recorded. The effects of age, axial length, anterior chamber depth (ACD), and lens thickness were evaluated. There were no significant preoperative differences in endothelium morphology between the two groups. The mean endothelial cell loss 1 month after surgery was 18.1% in the PEX group and 11.6% in the control group (p = 0.06). Phaco time and used BSS values were significantly higher in patients with PEX but had no significant influence on endothelial cell loss. In regression analysis phaco power (p = 0.02) and age (p = 0.004) had a significant influence on endothelial cell loss. PEX in interaction with overall phaco impact had a negative influence on endothelial cell loss (p = 0.05). PEX as a main effect was not found to have a negative influence on endothelial cell loss. However, PEX in cases of high phaco impact significantly increases the risk of endothelial cell loss.

In Vivo and In Vitro Feasibility Studies of Intraocular Use of Seprafilm to Close Retinal Breaks in Bovine and Rabbit Eyes

Seprafilm, a sodium hyaluronate/carboxymethylcellulose absorbable barrier developed to prevent adhesions after abdominal surgery, adheres well to wet tissue. The authors studied the efficacy of this film for sealing retinal breaks in animals. In an in vitro study, a retinal detachment with a hole was created in bovine eyecups after the vitreous gel was removed. Seprafilm was placed over the retinal hole, and the strength of the retinal adhesion was measured by pulling the film. Permeability was tested by applying methylene blue to the film covering the retinal break. Seprafilm also was soaked in balanced salt solution (BSS) incubated at 37 degrees C, and the pH of the BSS containing Seprafilm was measured as it melted. In an in vivo study, Seprafilm was powdered and mixed in BSS solution, and 0.1 mL was injected into the right vitreous cavity in study rabbits. The same amount of BSS was injected into the right vitreous cavity in control rabbits. Ophthalmologic examinations were performed. Bilateral electroretinograms were recorded simultaneously before and 6 weeks after injection. Both eyes were enucleated for histologic evaluation. Seprafilm adhered well to the retina, was impermeable to methylene blue, and remained solid in BSS for 30 days before it dissolved, and its pH ranged from 7.2 to 8.0. No intraocular inflammatory reaction occurred after intravitreous injection of Seprafilm solution. There was no significant difference in amplitudes or implicit times of electroretinogram a-waves, b-waves, and oscillatory potentials before and after injection and between study and control groups. No significant retinal abnormality was detected by light microscopy in either group. The film adhered well to the retina with no signs of ocular toxicities. Further study is warranted for possible means of patching retinal breaks.

Comparative clinical trial of ultrasound phacoemulsification with and without the WhiteStar system

To compare the postoperative outcomes of cataract surgery performed with the Sovereign 4.0 system or the Sovereign system with WhiteStar power modulation. Ambulatory surgery centers at 4 sites in the United States. This was a 3-month, open-label, randomized, parallel-group comparative clinical trial in patients with visually interfering cataract. Surgeons used the divide-and-conquer phacoemulsification technique for nuclear removal. An intraocular lens was implanted using the recommended insertion system. Primary operative outcome measures were equivalent phaco time (EPT), percentage of phaco power, amount of balanced salt solution used, and surgical complications. Patients were seen 1 day and 3 months after surgery. Postoperative outcome measures were the change in endothelial cell count from the preoperative visit to 3 months, corneal clarity, inflammation, and corneal thickness. The Sovereign with WhiteStar group had 48 patients and the Sovereign 4.0 group, 49 patients. Mean EPT and mean percentage of power were significantly lower in the Sovereign with WhiteStar group. Mean EPT was 6.67 seconds +/- 8.2 (SD) in the Sovereign with WhiteStar group and 8.59 +/- 9.3 seconds (P = .01) in the Sovereign 4.0 group. Mean percentage of phaco power was 6.41% +/- 3.3% in the Sovereign with WhiteStar group and 8.51% +/- 4.9% in the Sovereign 4.0 group (P = .01). The Sovereign with WhiteStar group lost significantly fewer endothelial cells (-319.6 +/- 634.2 cells/mm(2)) than the Sovereign 4.0 group (-430.3 +/- 594.6 cells/mm(2)) (P = .01). Corneal clarity, cells and flare, and pachymetry were comparable with the exception of the 3-month visit. The mean change in baseline central pachymetry showed significantly less corneal thickening in the Sovereign with WhiteStar group. The Sovereign with WhiteStar power modulation system provides effective lens removal at lower levels of phaco power and ultrasound energy than the Sovereign 4.0 system. Lower ultrasound levels may reduce the risk for endothelial cell loss during phacoemulsification.

Reproduction of Echinostoma revolutum Rediae When Transferred to Uninfected Snails of Different Sizes

Mother rediae of Echinostoma revolutum were transplanted individually from infected to uninfected Stagnicola palustris ranging in length from 10 to 25 mm. The number of daughter rediae present at 30, 40, and 50 days after transfer was related to the size of the snail, progressively so with the age of the infection. There was also a direct relationship between the size of the snail and the maximum size attained by the rediae which in general was greater than that seen in naturally infected snails. When daughter rediae were transplanted in groups of five into snails 20 to 23 mm long, and examined 40 or 60 days later, none of the snails contained additional rediae and none of the rediae contained rediae and cercariae together, as is occasionally seen in natural infections. Transplantation of trematode larvae from infected to uninfected snails has been useful in studies on various aspects of larval development. Donges (1963) artificially infected snails with individual rediae of an echinostome (Isthmiophora spiculator) to determine the exact sequence of larval stages. Chernin (1966, 1967) developed a technique for transferring Schistosoma mansoni sporocysts and echinostome rediae into the cephalopedal sinus of Australorbis glabratus, and Heyneman (1966) successfully established echinostome infections by introducing either miracidia or rediae into the tissues of Lymnaea rubiginosa and Indoplanorbis exustus. Changes in the transplanted rediae and metacercariae of Metagonimoides oregonensis were studied by Meade and Pratt (1966). In a previous study the relationship between the size of the host and the size of the redial population of Echinostoma revolutum was examined (Zischke, 1967). Although it was established that the number of mother rediae produced by the sporocyst was related to the size of the snail host, the number of daughter rediae generated by mother rediae could only be indirectly estimated. Moreover, in laboratory Received for publication 23 June 1967. *Present address: Department of Biology, St. Olaf College, Northfield, Minnesota. From a dissertation submitted to the Graduate School of Tulane University in partial fulfillment of the requirements for the degree of Doctor of Philosophy. The study was supported in part by Grant 5-TI-AI-02 from the NIH, U. S. Public Health Service. infections only two generations of rediae were found whereas in naturally infected snails a third generation of rediae occasionally was seen in daughter rediae that were producing cercariae. The present study was undertaken to determine the number of daughter rediae produced when mother rediae of E. revolutum are transplanted into uninfected snails (Stagnicola palustris) of various sizes, and to establish whether transplanted daughter rediae produce an additional generation of rediae. MATERIALS AND METHODS Mature mother rediae, obtained from snails (S. palustris) which were previously exposed to 10 miracidia, were introduced through holes, drilled with a 20-gauge hypodermic needle, into the region of the body whorl of laboratory-reared snails. Mature daughter rediae were similarly introduced, either between the body whorl and the first whorl of the spire or between the first and second whorls of the spire. The rediae, together with a small amount of balanced salt solution (Dulbecco and Vogt, 1954) were placed in the hemocoel by means of a capillary tube (inner diameter, 0.4 to 0.8 mm). In vitro survival tests proved the balanced salt solution to be a suitable medium for maintaining rediae outside of the host. Care was taken to rupture the mantle so that the larvae would not be entrapped between the mantle and the shell. The opening was sealed with silicone and over-sealed with melted paraffin applied with a small artist's brush. The wound healed completely in 4 to 6 days. All procedures were carried out under a hood and with sterile instruments and glassware. Reports published by several authors subsequent to the completion of this study suggest that the latter precautions may not greatly increase transplant success. All snails were maintained at 20 to 25 C.