A Novel Method to Assess the Cornea Biomechanical Properties With Schiotz Tonometer

Keratoconus Clinical Trial

Official title:

A Novel Method to Assess the Cornea Biomechanical Properties With Schiotz

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT02475343
• Other study ID #: No.018
• Status: Recruiting
• Phase: N/A
• First received: May 28, 2015
• Last updated: November 16, 2015
• Start date: February 2015
• Est. completion date: June 2016

Study information

• Verified date: November 2015
• Source: Shandong Provincial Hospital
• Contact: Zhiwei Li, MD.
• Phone: +86-18053106729
• Email: zhiweiovs[@]hotmail.com
• Is FDA regulated: No
• Health authority: China: National Health and Family Planning Commission
• Study type: Interventional

Clinical Trial Summary

This study aims to use Schiotz tonometer to evaluate the corneal biomechanical properties. The administration of Schiotz tonometer is according to the routine protocol which is use to measure intra-ocular pressure. The results obtained from Schiotz tonometer will be compared with results obtained from ORA and/or Corvis.

Description:

Schiotz tonometer, since it firstly be developed more than 100 years ago by Hjalmar Schiotz, has been regarded as a classical method to evaluate intraocular pressure (IOP). In present study, we aims to measure the corneal biomechanical properties with schiotz tonometer and elucidate the clinical significance of this novel measurement. The corneal biomechanical property was calculated with subtracting the value displayed under loaded weight 5.5g from that under loaded weight 7.5g. We named the corneal biomechanical properties obtained with schiotz tonometer as Mulee factor, and the formulation is Mulee factor=value under loaded weight 7.5g (Value 7.5G)-value under loaded weight 5.5g (Value 5.5G).

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 1000
• Est. completion date: June 2016
• Est. primary completion date: May 2016
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• People without the disease mentioned in exclusion criteria part.

Exclusion Criteria:

• Patients with ocular diseases including keratitis, conjunctivitis, history of chronic eye/systemic diseases except myopia and keratoconus, history of ocular surgery except LASIK, pregnant or lactating females.

Study Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Single Blind (Investigator), Primary Purpose: Diagnostic

Related Conditions & MeSH terms

• Keratoconus

Intervention

Device:
• Schiotz tonometer
The corneal biomechanical properties will be measured using a Schiotz tonometer with routine manipulation protocol.This measurement will be used in normal people, keratoconic patients, patients received keratoplasty.
• UVA/riboflavin
The UVA/riboflavin corneal crosslinking will be applied using a UV-X lamp (Peschke Meditrade GmbH, Switzerland) with routine manipulation protocol (3mW/cm2, 365nm, 30 minutes).This treatment will be used in keratoconic patients.
• femto-LASIK
The keratoplasty mainly include femto-LASIK (Laser in situ keratomileusis), which will be applied using a Wavelight FS200 and Wavelight EX500 Excimer Laser (Alcon Inc. USA.).The keratoplasty will be applied in patients who would like to receive the surgery.
• Tomey SP-100 Pchymeter , Topolyzer Vario
Cornea thickness will be measured with a pachymeter (Tomey SP-100 Pchymeter, Japan); cornea topography will be measured with Topolyzer Vario (Allegro, Wavelight GmBH, Germany); anterior chamber depth, white to white, and ocular axis length will be measured using a IOL master (Carl Zeiss Meditec, Germany). These measurements will be used in normal people, keratoconic patients, patients received keratoplasty.
• Topcon CT-80, Topcon, Japan
Vision acuity will be measured with a decimal visual chart; IOP (Intra-ocular pressure) will be measured with a tonometer (Topcon CT-80, Topcon, Japan) , fundoscopy examination will be apllied with a direct ophthalmoscopy, slit lamp examination will be applied with a slit lamp. These examinations will be used in normal people, keratoconic patients, patients received keratoplasty.
• Corvis-ST
Cornea biomechanical properties will be measured with a ocular response analyzer (Reichert, USA.) and/or a Corvis-ST (Oculus, Germany).These measurements will be used in normal people, keratoconic patients, patients received keratoplasty.

Locations

Country	Name	City	State
China	Shandong Provincial Hospital	Jinan	Shandong

Sponsors (1)

Lead Sponsor	Collaborator
Zhiwei Li

Country where clinical trial is conducted

China, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The Mulee factor obtained with Schiotz tonometer as a measure of cornea biomechanical property	Mulee factor= Value displayed with Schiotz tonometer under 7.5g load-Value displayed with Schiotz tonometer under 5.5g load	up to 1 year	No