OHM

Comparative quantification of ingress of trypan blue into anterior chamber following

microcoaxial phacoemulsification with torsional or longitudinal ultrasound

The authors have received travel expense reimbursement from Alcon Laboratories, USA

Abhay Vasavada, Vaishali A Vasavada, Devarshi Gajjar,

Shetal Raj

Iladevi Cataract and IOL Research Center, Ahmedabad,

India

Berdahl JP, Jun P, DeStafeno JJ, et al

Comparison of a torsional handpiece through microincision versus standard clear corneal cataract wounds

J Cataract Refract Surg 2008; 34 (12): 2091-2095

Phacoemulsification using the OZil™ handpiece through a microincision with an Ultrasleeve and a 45-degree miniflared tip showed favorable clinical and intraoperative characteristics such as less total energy use and less endothelial cell loss at 6 months

Introduction

Praveen MR, Vasavada AR, Gajjar D, et al

Comparative quantification of ingress of trypan blue into the anterior chamber after microcoaxial, standard coaxial, and bimanual phacoemulsification: randomized clinical trial

J Cataract Refract Surg 2008 Jun; 34 (6): 1007-12

* Trypan blue ingress into the anterior chamber found in all three groups.

* There was no significant difference between the standard coaxial and microcoaxial phacoemulsification following IOL implantation.

Aim To compare ocular surface fluid ingress into the anterior

chamber during microcoaxial phacoemulsification performed

with the Torsional ultrasound (Ozil™) and Longitudinal

ultrasound using Trypan Blue as the quantifying tracer

Study design: Study design: Prospective, Randomized, Masked studyProspective, Randomized, Masked study

Study population: Study population:

80 consecutive patients undergoing phacoemulsification for 80 consecutive patients undergoing phacoemulsification for uncomplicated age-related cataractsuncomplicated age-related cataracts

80 eyes - Random allocation into 2 groups:80 eyes - Random allocation into 2 groups:

Group ITorsional ultrasound

(n = 40)

Group IILongitudinal ultrasound

(n = 40)

Exclusion Criteria

• Dense cataracts (> grade 4), uveitis, shallow anterior chamber, glaucoma, high myopia (AL > 25mm)

• Intraoperative complications: Wound site thermal injury (WSTI), Posterior capsule rupture, Incisional damage / suture

Materials And MethodsMaterials And Methods

Surgical TechniqueSurgical Technique

•All surgeries performed by a single surgeon (ARV)

•Microcoaxial phacoemulsification performed on the Infiniti

Vision System ™

• 2.2mm temporal single plane clear corneal incision

• Standardized surgical parameters

• 0.9mm miniflared ABS 45 deg Kelman tip used

Surgical Parameters Used

Group II: Longitudinal Ultrasound

•Torsional amplitude : Ozil continuous with linear control, upto 80

•Aspiration flow rate (AFR) : 25cc/min

•Vacuum (mmHg) : upto 650mmHg ( depending on grade cataract )

•Bottle height : 90-110cm

•Preset U/S power (Pulse mode) : 60% preset, 40 pps, 40% on time

•Aspiration flow rate (AFR) : 25cc/min

•Vacuum (mmHg) : upto 650mmHg ( depending on grade cataract )

•Bottle height : 90-110cm

Group I: Torsional Ultrasound (Ozil ™)

Methodology

All incisions were hydrated

Speculum was removed

Trypan blue applied over conjunctiva

Encouraged to blink for 2 min

After IOL implantationAfter IOL implantation

0.1ml aqeous aspirated0.1ml aqeous aspirated

Observation

Quantify the ingress of trypan blue in anterior chamber in the two groups

** Trypan blue was first scanned at different wave lengths (190nm Trypan blue was first scanned at different wave lengths (190nm to 900nm) using a U.V visible spectrophotometerto 900nm) using a U.V visible spectrophotometer

** The maximum optical density of trypan blue was found to be at The maximum optical density of trypan blue was found to be at 595nm595nm

** A standard graph using different dilutions of trypan blue was A standard graph using different dilutions of trypan blue was createdcreated

Quantification of Trypan BlueQuantification of Trypan Blue

Standard GraphSpectrophotometry of Trypan blue

00.5

11.5

22.5

33.5

44.5

0 0.6 1 1.6 2 2.6 3 4 5

Log dilution with Normal saline

Absorb

ance a

t

Comparison of log of denominators of Trypan blue ingress into the anterior chamber between the two groups:

GROUP N MEAN + SD MIN. MAX.

OzilTM 40 3.77 + 0.82* 1.0 4.75

Longitudinal ultrasound 40 3.40 + 0.60 1.6 4.75

Mann Whitney U Test P= 0.007

ResultsResults

* Higher Log value of Trypan blue ingress indicates lesser amount of Trypan blue in the anterior chamber

Conclusion

• Trypan blue ingress was found in both groups

• Trypan Blue ingress was statistically significantly

greater following phacoemulsification with

Longitudinal ultrasound as compared to Torsional

ultrasound (OzilTM)