Medications Effect on Lenstar Measurements

The Effects of Dilation Medication on Lenstar Measurements for Cataract Surgery

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02780063

Enrollment

Registered

2016-05-23

Start date

2015-09-18

Completion date

2018-07-24

Last updated

2019-01-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cataract

Keywords

Dilation, Intraocular, Ophthalmology

Brief summary

Prior to cataract surgery the lens must be calculated to appropriately fit a patient for the intraocular lens implant. Lenstar is an optical biometer that calculates the axial length, keratometry, lens thickness, pupillometry, and anterior chamber depth. Dilation drops are routinely used in eye exams in addition to pre-cataract surgery. The dilation drops include Tropicamide 1%, and Phenylephrine 2.5%. The Tropicamide achieves the dilation of the pupil which causes an anterior rotation of the ciliary body, which may affect the Lenstar measurements. This study is to determine if dilating medications affect the lens power prediction for emmetropia by the Lenstar biometer. Prior to dilation, Lenstar biometry will be performed on each eye. Patients will receive dilation medication and after waiting 20 minutes Lenstar biometry will be performed on each eye. Dilation and measurement with Lenstar will be done as standard of care. Measurements and calculations from before and after will be compared.

Interventions

OTHERLenstar Biometer

uses optical principles (laser interferometry) to measure axial length, measuring distance from the corneal apex to the retinal RPE. In addition to axial length, it also measures corneal thickness, anterior chamber depth, lens thickness, radii of curvature of flat and steep meridian, axis of flat meridian, white to white distance, and pupil diameter.

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

SCREENING

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

50 Years to No maximum

Healthy volunteers

Inclusion criteria

* Candidates for cataract surgery undergoing routine evaluation of cataracts.

Exclusion criteria

* Patients that have had their cataracts removed * Patients that cannot undergo routine evaluation for cataract surgery (because they are too ill to sit upright in a chair)

Design outcomes

Primary

Measure	Time frame
Baseline Lens Power will be compared to Post dilation measurements using Lenstar biometer	One Day

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026