Clinical trial NCT03473847: Repeatability, Reproducibility and Comparison of Cirrus OCT, RTVue OCT, MS-39 OCT, and Insight 100 VHFDU
Official title: Repeatability and Reproducibility of Carl Zeiss Meditec Cirrus HD OCT 5000, Optovue RTVue OCT, CSO MS-39 OCT and ArcScan Insight 100 Very High-frequency Digital Ultrasound and Comparison Between Devices
Study type: INTERVENTIONAL
Overall status: SUSPENDED
Phase: NA
Conditions: Corneal Thickness Measurement
Epithelial Thickness Measurement
LASIK Flap Thickness Measurement
SMILE Cap Thickness Measurement
Keywords: VHF digital ultrasound
Optical coherence tomography
Corneal thickness
Epithelial thickness
LASIK
SMILE
Lead sponsor: London Vision Clinic
Sponsor class: OTHER
Collaborators: name: Carl Zeiss Meditec AG
First posted: 2018-03-22
Enrollment: 242
Sex: ALL
Minimum age (years): 21
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Scans from 4 devices obtained on the same patient population for comparison
Primary purpose: DIAGNOSTIC

Brief summary: The purpose of this study is to evaluate the repeatability and reproducibility of corneal, epithelial, and LASIK flap thickness using the Carl Zeiss Meditec Cirrus HD OCT 5000, Optovue RTVue OCT, CSO MS-39 OCT, and ArcScan Insight 100 very high-frequency digital ultrasound arc-scanner.

Detailed description: Very high-frequency (VHF) digital ultrasound was first used in 1993 to obtain images and measure the thickness of the cornea (the window at the front of the eye) and the layers within the cornea, such as the epithelium (the layer of skin on the surface of the cornea). A commercially available instrument, known as the Artemis, has been used in routine clinical practice since 2001. The ArcScan Insight 100 VHF digital ultrasound scanner is an updated version, which obtained CE mark in 2016.

Optical coherence tomography (OCT) is another method of measuring the thickness of the cornea and the corneal epithelium. OCT has been used for measuring corneal thickness since 1997 and the technology had evolved to also measure epithelial thickness since 2012. There are currently three OCT scanners capable of measuring epithelial thickness; Carl Zeiss Meditec Cirrus HD OCT 5000, Optovue RTVue OCT, CSO MS-39 OCT.

The aim of the study is to establish the repeatability (i.e. the variability in measurements taken by a single examiner during a single visit) and reproducibility (i.e. the variability in measurements taken in the same conditions between two examiners) for each of the four devices for measuring corneal thickness and epithelial thickness.

Eligibility criteria: Inclusion Criteria:

Only patients who are medically suitable for corneal laser refractive surgery can be included in the study.

As general inclusion criteria the following aspects are defined:

* Subjects should be 21 years of age or older.
* Contact lens wearers must stop wearing their contact lenses at least four weeks per decade of wear before baseline measurements in case of hard contact lenses and one week before baseline measurements in case of soft contact lenses.
* Patient will be able to understand the patient information and willing to sign an informed consent.

For the normal eye populations:

* Eyes with no ocular pathology
* Eyes with no previous ocular or corneal surgery

For the post-op eye populations:

• Eyes between 3 and 9 months after LASIK or SMILE

Exclusion Criteria:

* Previous ocular or corneal surgery (for normal eyes)
* Patient not being able to tolerate local or topical anesthesia
* Patient has active conjunctivitis or any active ocular infection or inflammation
* Patient has a corneal ulcer
* Patient has an open wound on the corneal epithelium
* Patient has compromised epithelium (e.g. ≥Grade 3 superficial punctate keratitis)
* Pregnancy

Primary outcomes:
measure: Repeatability and reproducibility of Cirrus HD OCT 5000 corneal scans in normal eyes (standard deviation)
timeFrame: 10 minutes (5 minutes per observer)
measure: Repeatability and reproducibility of RTVue OCT corneal scans in normal eyes (standard deviation)
timeFrame: 10 minutes (5 minutes per observer)
measure: Repeatability and reproducibility of MS-39 OCT corneal scans in normal eyes (standard deviation)
timeFrame: 10 minutes (5 minutes per observer)
measure: Repeatability and reproducibility of Insight 100 VHF digital ultrasound corneal scans in normal eyes (standard deviation)
timeFrame: 30 minutes (15 minutes per observer)
measure: Repeatability and reproducibility of Cirrus HD OCT 5000 corneal scans in post-op eyes (standard deviation)
timeFrame: 10 minutes (5 minutes per observer)
measure: Repeatability and reproducibility of RTVue OCT corneal scans in post-op eyes (standard deviation)
timeFrame: 10 minutes (5 minutes per observer)
measure: Repeatability and reproducibility of MS-39 OCT corneal scans in post-op eyes (standard deviation)
timeFrame: 10 minutes (5 minutes per observer)
measure: Repeatability and reproducibility of Insight 100 VHF digital ultrasound corneal scans in post-op eyes (standard deviation)
timeFrame: 30 minutes (15 minutes per observer)
measure: Difference in corneal thickness measurements between Cirrus HD OCT 5000, RTVue OCT, MS-39 OCT, and Insight 100 VHF digital ultrasound in normal eyes
timeFrame: 20 minutes for all four scans
measure: Difference in corneal thickness measurements between Cirrus HD OCT 5000, RTVue OCT, MS-39 OCT, and Insight 100 VHF digital ultrasound in post-op eyes
timeFrame: 20 minutes for all four scans
Secondary outcomes:
Other outcomes:
Locations:
city: London
country: United Kingdom
facility: London Vision Clinic
Study officials:
affiliation: London Vision Clinic
name: Dan Z Reinstein, MD, MA, FRCOphth
role: PRINCIPAL_INVESTIGATOR
References:
citation: Reinstein DZ, Archer TJ, Gobbe M, Silverman RH, Coleman DJ. Repeatability of layered corneal pachymetry with the artemis very high-frequency digital ultrasound arc-scanner. J Refract Surg. 2010 Sep;26(9):646-59. doi: 10.3928/1081597X-20091105-01. Epub 2009 Nov 16.
citation: Reinstein DZ, Yap TE, Archer TJ, Gobbe M, Silverman RH. Comparison of Corneal Epithelial Thickness Measurement Between Fourier-Domain OCT and Very High-Frequency Digital Ultrasound. J Refract Surg. 2015 Jul;31(7):438-45. doi: 10.3928/1081597X-20150623-01.
citation: Yap TE, Archer TJ, Gobbe M, Reinstein DZ. Comparison of Central Corneal Thickness Between Fourier-Domain OCT, Very High-Frequency Digital Ultrasound, and Scheimpflug Imaging Systems. J Refract Surg. 2016 Feb;32(2):110-6. doi: 10.3928/1081597X-20151223-01.
citation: Kiraly L, Stange J, Kunert KS, Sel S. Repeatability and Agreement of Central Corneal Thickness and Keratometry Measurements between Four Different Devices. J Ophthalmol. 2017;2017:6181405. doi: 10.1155/2017/6181405. Epub 2017 Mar 5.