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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Kala Pharmaceuticals announced that it will be presenting at the Spotlight on dry eye session at the Ophthalmology Innovation Summit at the American Society of Cataract and Re…. It is therefore important to note that some corneas will not satisfy the requirements for correct IOP measurements with DCT. Statistical analysis was performed gonometry a homoscedastic, 2-tailed t test.

Elevated intraocular pressure IOP is generally regarded as one of the major risk factors for glaucoma, and its reduction is the most frequently used surrogate of successful management of risk factors.

Corneal structure or biomechanics varies among patients even when CCT is the same. Reduction in intraocular pressure after excimer laser photorefractive keratectomy: KaufmannNone; L. The bottle heights were increased in 5-cm increments up to a maximum of 75cm 58 mm Hg. This site uses cookies. Findingthe right point in this changing environment at which to determine the “true”manometric pressure is difficult if not impossible. Pneumatonometryespecially causes the initial rise in pressure by as much as 10 mm Hg.

In the low- and moderate-pressure range, inaccuracy of the GAT and the PTGwas not great and not likely to be of major clinical significance, but alsowas not linear. Fourth, DCT was performed using a technically identical prototype of the model launched in November Pascal dynamic contour tonometer; Swiss Microtechnology AG, Port, Switzerland; slit-lamp—mounted, self-calibrating, 1 g toometry force, Hz sampling rate, 7 mm tip diameter, 1.

About Glaucoma Today Glaucoma Today is mailed bimonthly six times a year to 11, glaucoma specialists, general ophthalmologists, and clinical optometrists who treat patients with glaucoma. Accuracy of Goldmann tonometry in clinical practice. Excluded were patients with pseudoexfoliation, a history of trauma, pigmentary dispersion, narrow or closed iridocorneal angle, evidence of any secondary glaucoma, any type of preceding refractive surgery and corneal disease, and chronic or recurrent inflammatory eye disease eg, scleritis or uveitis.


The contoured tip features a concave surface with a radius of Furthermore, the accuracy seems to be independent ofcorneal thickness and corneal curvature within the limits of this study. Create a personal account to register for email alerts with links to free full-text articles. Similarly, PTG gives a more objectivevalue. Relationship between corneal thickness and measured intraocular pressure in a general ophthalmology clinic. The transducer and the anterior chamber were kept at the sameheight.

Data are presented tonomwtry medians and 25th to 75th percentile limits. The device seems to be particularly useful for IOP measurements in post-LASIK eyes tonpmetry well as in other corneas contoru are thinner or thicker than average and in which the practitioner cannot achieve accurate contout by force tonometry.

Data points are transferred to a microprocessor-based control unit, whichcomputes and displays the measured pressure.

Next the globe wasimmersed in dextran solution. The theoretical foundations of dynamic contour tonometry. Claude Kaufmann, Lucas M. Sign in to access your subscriptions Sign in to your personal account. Applanation tonometry is certainly knownto be influenced by corneal thickness.

Ehlers N, Hansen FK. The majority of tonometer designs proposed to date both the contact and the noncontact type are based on a common principle: Claude Kaufmann ; Lucas M.

Dynamic contour tonometry and GAT intraocular pressure differences significantly increased with older age slope, 0. In these eyes, anterior cornealradius before the experiment at an IOP of approximately 20 mm Hg was 7.

Dynamic Contour Tonometry

Since a value is given automatically by the strain gauge andthe automatic software in the base station, there is less chance for observerbias with this system than with GAT. Purchase access Subscribe to JN Learning for one year.

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 and the entry needle without torsion during the readings.

Register for email alerts with links to free full-text articles Access PDFs of free articles Manage your interests Save searches and receive search alerts. The right eye was always measured first. The chosen contour of the DCT tip will furnish correct measurements defined as measurements with a systematic error of less than 0. Over the past four decades, Goldmann applanation tonometry GAT has become the standard for routine measurement of IOP, as the method has proven to be robust and easy to use with low intra- and interobserver variability.


No significant correlation could be found between the real IOPand the degree of error of any of the tonometers. Dynamic contour tonometry provides 5 different quality levels, with 1 being the best and 5 being the poorest. Furthermore,the data show little difference in results between open and closed stopcockmethods. Goldmann Applanation Tonometry in the Conscious Rat. Create a free personal account to make a comment, download free article PDFs, sign up for alerts and more.

Twenty freshly enucleated human cadaver globes that were unsuitablefor transplantation were provided by the eye banks of San Diego, Calif, andPortland, Ore.

Glaucoma Today – Dynamic Contour Tonometry (March/April )

Intraocular pressure readings by DCT were computed and displayed by the instrument, thereby reducing tonomery observer bias. Glaucoma Today delivers important information on recent research, surgical techniques, clinical strategies, and technology.

In a closed system, the cadaver globe is subject touncontrollable fluid leakage. You will receive an email whenever this article is corrected, updated, or cited in the literature.

Create a free personal account to make a comment, download free article PDFs, sign up for alerts and more. Dnamic evidence has confirmed the wide variation in corneal thicknessand raised the possibility that corneas that are thicker or thinner than averagemight be associated with clinically significant overestimates or underestimatesof intraocular pressure IOP when measured with the GAT.

Because neither of the 2 methods can at the outset be assumed to be superior to the other, the difference between GAT and DCT was plotted against the mean of the 2 methods for analysis of individual pairs according to the method by Bland and Altman.

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