Immediate effects of cigarette smoking on the cornea and front of the eye

Acute Effects of Cigarette Smoking on Corneal Tomographic and Biometric Parameters: A Prospective Controlled Study

Observational Istanbul University · NCT07580040

Researchers will see if 10 minutes of cigarette smoking causes immediate changes in corneal tomography and other front-of-eye measurements in healthy adult smokers compared with never-smokers.

Quick facts

Study typeObservational
Enrollment90 (estimated)
Ages18 Years to 60 Years
SexAll
SponsorIstanbul University Academic / other
Locations1 site (Istanbul)
Trial IDNCT07580040 on ClinicalTrials.gov

What this trial studies

This is a single-center, prospective, controlled study that compares short-term corneal tomographic and biometric measurements between current smokers and never-smokers. Baseline eye exams and Pentacam AXL measurements are taken on the right eye only, then participants spend 10 minutes outdoors during which smokers smoke and controls do not. The same measurements are repeated immediately after the exposure period to capture acute changes. Within-group and between-group differences in measurement changes are then compared.

Who should consider this trial

Good fit: Healthy adults aged 18–60 who are either current cigarette smokers (for the smoking group) or never-smokers (for the control group) and who can undergo Pentacam AXL measurements are ideal candidates.

Not a fit: People with prior ocular surgery or trauma, existing corneal or retinal disease, significant dry eye, recent contact lens use, systemic diseases like diabetes or hypertension, former smokers, or users of e-cigarettes or other tobacco products are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, the study could show whether very short-term smoking causes measurable changes in corneal shape or thickness, which could inform patient counseling and interpretation of diagnostic measurements.

How similar studies have performed: Prior work has documented chronic smoking effects on the eye, but immediate corneal tomographic changes after very short smoking exposure are relatively untested.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Healthy adults aged 18 to 60 years
* Current smokers in the smoking group
* Never-smokers in the control group
* Willing and able to undergo ophthalmic examination and Pentacam AXL measurements

Exclusion Criteria:

* History of ocular surgery or ocular trauma
* Presence of corneal disease, retinal disease, or ocular surface disorder
* Clinically significant dry eye disease
* Contact lens use within the last 2 weeks
* Use of medications that may affect the ocular surface or pupillary dynamics, including anticholinergics or sympathomimetics
* Systemic diseases such as diabetes mellitus or hypertension
* Former smoking history in the control group
* Use of electronic cigarettes or other tobacco products
* Inability to cooperate adequately for accurate measurement

Where this trial is running

Istanbul

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions SmokingCorneaAnterior Eye Segment MeasurementsCigarette SmokingCorneal TomographyBiometryPentacamAnterior Segment
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.