Reliability of Hertel Exophthalmometer Measurements

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
David Chesnutt, MD, University of North Carolina, Chapel Hill
ClinicalTrials.gov Identifier:
NCT01691183
First received: June 5, 2012
Last updated: September 21, 2012
Last verified: September 2012
  Purpose

The purpose of this research study is to learn about the variability in proptosis measurements. Measurements will be recorded using the Hertel exophthalmometer. This noninvasive tool is an instrument designed to measure the forward protrusion of the eye and may be used normally during a general eye exam. This instrument provides a method of evaluating and recording the progression and regression of the prominence of an eye caused by disorders such as thyroid disease and tumors of the orbit.


Condition
Standardization of Hertel Measurements

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Reliability of Hertel Exophthalmometer Measurements

Further study details as provided by University of North Carolina, Chapel Hill:

Primary Outcome Measures:
  • Proptosis [ Time Frame: approximately 5 minutes ] [ Designated as safety issue: No ]
    Amount of protrusion of eye from orbital rim measured in millimeters. Two people will be taking both a baseline and a secondary measurement to assess standardization of the "base measurement".

  • "Base Measurement" [ Time Frame: approximately 5 minutes ] [ Designated as safety issue: No ]
    User #1 will take a baseline measurement and then a second measurement to help evaluate intrauser variability. User #2 will then independently take a baseline measurement (to help evaluate interuser variability) and then a second measurement after being provided only the base measurement of user #1's first measurement, in order to help determine if standardizing the base measurement will improve interuser variability.


Secondary Outcome Measures:
  • Orbital Disease status [ Time Frame: baseline ] [ Designated as safety issue: No ]
    Record presence or absence of orbital disease at time of measurement


Enrollment: 85
Study Start Date: May 2012
Study Completion Date: June 2012
Primary Completion Date: June 2012 (Final data collection date for primary outcome measure)
Groups/Cohorts
Study Subjects
Subjects with or without orbital disease that present to clinic for scheduled appointments.

Detailed Description:

Aim 1. In order to determine intrauser reliability of the Hertel exophthalmometer, patients will have 2 independent exams using the Hertel exophthalmometer on the same day performed by each of the same researcher (either DAC or HLP) in a blinded fashion. For each patient, we will independently measure the base value and the values for the right and left eye proptosis, respectively, using the same Hertel exophthalmometer. A randomization process will be employed to determine which researcher (either DAC or HLP) will take the first set of measurements. The distance of the observer from the patient will be standardized for all measurements. Patient research data will be de-identified and recorded for each patient and subsequently analyzed for interobserver reliability.

Aim 2. In order to determine interuser reliability of the Hertel exophthalmometer, patients will have a second independent exam on the same day by the second observer as determined for Aim 1 above. For each patient, we will independently measure the base value and the values for the right and left eye proptosis, respectively, using the same Hertel exophthalmometer. The distance of the observer from the patient will be standardized for all measurements.

Patient research data will be de-identified and recorded for each patient and subsequently analyzed for interobserver reliability.

Aim 3. Variability in Hertel measurements may be related in large part to differences in the base measurement. The base measurement is determined by the bony orbital structures and should not be significantly affected over time by the soft tissue remodeling commonly seen in TED and most other orbital disease processes. We will have the second observer re-measure the same patient using the same Hertel exophthalmometer by beginning with the same base measurement determined by the first observer. Again, all measurement distances will be standardized. No other information will be provided to the second observer other than the beginning base measurement. Patient research data will again be de-identified prior to recording the information and subsequently analyzed to determine if beginning with the same base improves interobserver reliability.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

150 consecutive adult patients of both sexes and all ages will be recruited by David Chesnutt MD from the UNC Eye Clinic. Patients taken from a pool of patients already scheduled for appointments.

Criteria

Inclusion Criteria:

  • Patients will be at least 18 years old and will be able to converse in written and spoken English.

Exclusion Criteria:

  • None
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01691183

Locations
United States, North Carolina
UNC Kittner Eye Center
Chapel Hill, North Carolina, United States, 27599
Sponsors and Collaborators
University of North Carolina, Chapel Hill
Investigators
Principal Investigator: David Chesnutt, MD UNC Chapel Hill
  More Information

No publications provided

Responsible Party: David Chesnutt, MD, Assistant Professor, University of North Carolina, Chapel Hill
ClinicalTrials.gov Identifier: NCT01691183     History of Changes
Other Study ID Numbers: 12-0705
Study First Received: June 5, 2012
Last Updated: September 21, 2012
Health Authority: United States: Institutional Review Board

Keywords provided by University of North Carolina, Chapel Hill:
Hertel
exophthalmometer
proptosis
eye disease

ClinicalTrials.gov processed this record on August 20, 2014