Study of Phacodepth Required for Safe and Effective Chop During Phacoemulsification for Cataract.

Study Results

Results available

Outcome measurements, participant flow, baseline characteristics, and adverse events have been published for this study.

View full results

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Total Enrollment

200 participants

Study Classification

OBSERVATIONAL

Study Start Date

2010-11-30

Study Completion Date

2011-02-28

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

There is a correlation between phacodepth required for full thickness nuclear crack and the various grades of cataract

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

BACKGROUND:- Phacochop techniques have been categorized as either horizontal or vertical. These approaches are thought to be among the best techniques for managing hard cataracts. In vertical chop technique proper placement of the phaco tip is crucial. It must be embedded deeply into the centre of the nucleus , pointing toward the optic nerve , with high vacuum and burst mode.Inadequate penetration of phacotip may result in partial thickness nuclear crack with residual posterior plate and overzealous penetration may result in posterior capsular rupture.This may be avoided if some estimate can be made preoperatively of the depth of penetration required to achieve full thickness crack. With this in mind the study intends to make a preoperative assessment of the depth required to reach the centre of the nuclei and observe the actual depth of penetration required for a safe and effective vertical chop.

MATHEMATICAL BASIS :- The cross section of a lens nucleus is ellipsoidal . A geometrical estimate of the radius of the ellipse (x )traversed by the phacotip to reach the centre can be made preoperatively.The calculation would depend largely on three parameters.

The major axis of the ellipse ( namely the lens diameter\[b\] ) The minor axis of the ellipse (namely lens thickness\[a\] ) The point of entry on the surface of the lens.This defines an angle Ø which this radius makes with the vertical axis and in turn can be approximated by the length of the arc from centre of lens surface to entry point\[y\].

Adult human crystalline lens varies in thickness from 4.2+/-0.5 mm and has a diameter of 9.6+/- 0.4mm. Assuming the lens diameter (b) to be from 9.2 mm to 10.0mm , the lens thickness ( a) varying from 3.7mm to 4.7mm and the point of entry of phacotip 2.0mm to 3.0mm from centre of anterior lens surface ( y ) , this distance (x) would vary from 2.59mm to 3.2mm.(using Online Wolfram calculator) in thinnest to thickest nuclei. This would be increased with increase in ( a ) as well as ( y ) .In cataractous lens the harder a nucleus the deeper it may be required to penetrate to achieve a full thickness crack.

If the investigators make a note of all three variables i.e lens thickness , nuclear hardness and point of entry at the time of surgery and correlate with the actual depth required at the time of surgery the investigators may be able to recommend an effective and safe phacodepth for achieving full thickness nuclear crack in various grades of hard cataract.

Till now it was not possible to measure the length of penetration of phacotip during surgery. The investigators have designed a calibrated phacotip with visible markings on 0.2mm scale from 2 to 3. 4mm to enable measurements and recordings.

Thus the investigators aim to identify a safe and effective phacodepth required in each grade of cataract {3.0 - 6.9 according to Lens Opacities Classification System( LOCS-III )}to achieve successful nuclear crack . At the same time any correlation between different nuclear grades and the effective phacodepth would be analysed to find any association between them.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Cataract

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

cataract phacoemulsification phacochop phacotip

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Study Time Perspective

CROSS_SECTIONAL

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Patients (\> 40 years of age) with grade 3.0 to 6.9( according to LOCS-III) of senile cataract will be included in this study

Exclusion Criteria

1. Subluxated and dislocated lens.
2. Central leukomatous corneal opacity preventing visualization of cataractous lens for grading and surgery.

Minimum Eligible Age

40 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Dr. Praveen Kumar Malik

Professor and Consultant,ophthalmology

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Praveen K Malik, MS

Role: PRINCIPAL_INVESTIGATOR

Dr. R.M.L.Hospital,New Delhi,India

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

Dr. R.M.L.Hospital,

New Delhi, National Capital Territory of Delhi, India

Site Status

Countries

Review the countries where the study has at least one active or historical site.

India

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

RMLH-001-EYE

Identifier Type: -

Identifier Source: org_study_id