Clin Exp Ophthalmol. Dec;34(9) Dynamic contour tonometry: principle and use. Punjabi OS(1), Kniestedt C, Stamper RL, Lin SC. The PASCAL Dynamic Contour Tonometer (DCT) from Ziemer is a slitlamp mounted tonometer for measuring intraocular pressure IOP independent of corneal. The gold standard for assessing IOP is Goldmann applanation tonometry (GAT). Recently, the dynamic contour tonometer (DCT) has become.
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Correlation between central corneal thickness, applanation tonometry, and direct intracameral IOP readings. The intra- and interobserver variability found with GAT is very similar to the results found in other studies. A piezoelectric pressure sensor 1 is built in the concavity of the tip. Corneal thickness in ocular hypertension, primary open-angle glaucoma, and contlur glaucoma.
This feature is available to authenticated users only. For that reason, accurate IOP is a fundamental variable in clinical practice. Applanation tonometry is certainly knownto be influenced by corneal thickness.
Exposing a miniaturized pressure sensor closely to the contour of such a cornea is thought to measure IOP directly i. A magnitude and time analysis.
Bayesian adaptive assessment of the reading function for vision: Relationship between corneal thickness and measured intraocular pressure in a general ophthalmology clinic.
Reduction in intraocular pressure after excimer laser photorefractive keratectomy: At each bottle height, tonoetry 3 tonometer devices were used to obtain 5pressure readings. Glaucoma Today is mailed bimonthly six times a year to 11, glaucoma specialists, general ophthalmologists, and clinical optometrists who treat patients with glaucoma.
Bachmann ; Michael A. An average of 2 scans of cornealthickness measured in micrometers and anterior and posterior curvature inmillimeters and diopters were taken of each cornea, ensuring that the corneawas well moisturized contuor the entry needle without torsion during the readings.
Author Affiliations Claude Kaufmann. In the preliminary series of 4 eyes, the pressure measurements wereperformed by means of the closed stopcock tubing system first to compare itsapplicability and accuracy with the open tubing system, which was used onthe same eye immediately thereafter.
PASCAL® Dynamic Contour Tonometer from Ziemer Group – Product Description and Details
With the dynamic contour tonometer DCTa new digital tonometer has been introduced as an alternative to adjustments of applanation tonometry readings based on CCT. Sign in to download free tohometry PDFs Sign in to access your subscriptions Sign in to your personal account. To evaluate intra- and interobserver variability, IOP was measured in eight eyes by four observers.
Statistical analysis was performed with a dynami, 2-tailed t test. This is still more precise than the GAT readings used to date.
In this analysis, we used an interocular study design that has not been described previously, to our knowledge.
Several nomograms for adjusting GAT readings in normal eyes with varying CCT 5 6 7 or in eyes after refractive surgery 8 9 have been published, but so far none seems to be satisfactory. Create a personal account to register for email alerts with links to free full-text articles.
The majority of tonometer designs proposed to date both the contact and the noncontact type are based on a common principle: The variance component of the residual error is the intraobserver variability. Create a personal account to register for email alerts with links to free full-text articles. It is possible that this slight inaccuracy may be due tochanges in the corneal curvature as the pressure becomes very high.
This is slightly longer than the contact time that an experienced examiner would require with the GAT. In contrast to GAT, multivariable regression analysis showed no significant effect of corneal thickness, corneal curvature, astigmatism, anterior chamber depth, and axial length on DCT readings.
Create contoour free personal account to make a comment, download free article PDFs, sign up for alerts and more. Giventhe relatively narrow range of CCT measurements due to artificially distributedcorneal thickness, significant correlation would be difficult to obtain.
Nevertheless, it remains to be elucidated whether various topical glaucoma medications might confound the relationship between CCT and IOP. Corneal preparation of eye bank contout for experimental surgery. Myopic patients seem to be at a somewhat greater risk of developing glaucoma, thus warranting a particularly careful screening.
Comparison of Dynamic Contour Tonometry with Goldmann Applanation Tonometry | IOVS | ARVO Journals
This schematic view of the cornea shows the DCT tip interface in cross section. Interobserver variability was 0. Further studies are warranted todetermine its reliability in patients and the effect of corneal thickness. For repeated measurements the intraobserver variability was 0.
Dynamic Contour Tonometry
The advantage of an interocular or intraindividual comparison is minimal interference from other nonocular factors in different individuals. Many of these individuals are undergoing the surgical modification of their corneas via LASIK and other techniques.
Goldmann applanation tonometry was performed using a slitlamp Haag-Streit, Koeniz, Switzerland with a tonometer calibrated according to the manufacturer’s guidelines. Next the globe wasimmersed in dextran solution.