The contact and immersion ultrasound methods compared using the ray tracing method

• Autorzy: Falhar M. , Rehak J.
• Języki publikacji: EN

Abstrakty

EN

The goal of this article was to compare the contact and immersion ultrasound methods using simulated data. The pursued changes were interrelated with both the axial length of the eye and with partial biometry parameters. The results were compared with empirical data from real eye samples. The main analysing method was a modified algorithm for the ray tracing method created in the DELPHI programming environment (Borland Enterprise). The sample included 129 eyes (64% women and 36% men) of average age 73.65 (SD 9.33) scheduled for surgical removal of cataract. The average axial length was 23.12 mm (SD 1.31). The methods were compared using the simulated movement of the probe from central and coincident positions. We confirmed the tendency of the contact method to register more scattered beam which provides distorted biometric data from the periphery. This was verified by the real data analysis. The average axial length of the eye was 23.12 mm (SD 1.315), measured by the contact method and 23.26 mm (SD 1.298), measured by the immersion method. The difference between the methods was 0.145 mm. The most important changes occur in the vitreum depth which correlated with the total axial length (r = 0.89). The ray tracing method provided evidence of greater accuracy of the immersion method which was more sensitive to probe displacement and provided more accurate data. The axial length of the eye was longer according to the immersion method but this had only secondary influence on the accuracy of the method. Applanation of the cornea is the primary source of the contact method inaccuracy. The vitreum depth was the most influenced.

Słowa kluczowe

EN

biometry; ultrasound measurement; immersion and contact method; ray tracing

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Optica Applicata
• Rocznik: 2010
• Tom: Vol. 40, nr 1
• Strony: 77--92
• Opis fizyczny: Bibliogr. 29 poz.

Twórcy

autor

Falhar M.

autor

Rehak J.

• Faculty of Science, Palacky University, Olomouc, Czech Republic

Bibliografia

• [1] ELEFTHERIADIS H., IOLMaster biometry: refractive results of 100 consecutive cases, British Journal of Ophthalmology 87(8), 2003, pp. 960–963.
• [2] OLSEN T., Sources of error in intraocular lens calculation, Journal of Cataract and Refractive Surgery 18(2), 1992, pp. 125–129.
• [3] NARVÁEZ J., ZIMMERMAN G., STULTING R.D., CHANG D.H., Accuracy of intraocular lens power prediction using the Hoffer Q, Holladay 1, Holladay 2 and SRK/T formulas, Journal of Cataract and Refractive Surgery 32(12), 2006, pp. 2050–2053.
• [4] HILL W.E., Highly accurate IOL calculations, Cataract and Refractive Surgery Today, URL: www.crstoday.com, March 2005, Download: 17.11.2005.
• [5] VETRUGNO M., CARDASCIA N., CARDIA L., Anterior chamber depth measured by two methods in myopic and hyperopic phakic IOL implant, British Journal of Ophthalmology 84(10), 2000,pp. 1113–1116.
• [6] HŘEBCOVÁ J., VAŠKŮ A., Comparison of contact and immersion techniques of ultrasound biometry, Česká a Slovenská Oftalmologie 64(1), 2008, pp. 16–18 (in Czech).
• [7] WATSON A., ARMSTRONG R., Contact or immersion technique for axial length measurement?, Australian and New Zealand Journal of Ophthalmology 27(1), 1999, pp. 49–51.
• [8] HOFFMANN P.C., HÜTZ W.W., ECKHARDT H.B., HEURING A.H., Intraocular lens calculation and ultrasound biometry: immersion and contact procedures, Klinische Monatsblätter für Augenheilkunde 213(9), 1998, pp. 161–165 (in German).
• [9] OLSEN T., NIELSEN P.J., Immersion versus contact technique in the measurement of axial length by ultrasound, Acta Ophthalmologica 67(1), 1989, pp. 101–102.
• [10] KRONBAUER A.L., KRONBAUER F.L., KRONBAUER C.L., Comparative study of the biometric measurements made by immersion and contact techniques, Arquivos Brasileiros de Oftalmologia 69(6), 2006, pp. 875–880 (in Portugese).
• [11] BEN-ZION I., NEELY D.E., PLAGER D.A., OFNER S., SPRUNGER D.T., ROBERTS G.J., Accuracy of IOL calculations in children: comparison of immersion versus contact A-scan biometry, J AAPOS 12(5), 2008, pp. 440–444.
• [12] HENNESSY M.P., FRANZCO, CHANG D.G., Contact versus immersion biometry of axial length before cataract surgery, Journal of Cataract and Refractive Surgery 29(11), 2003, pp. 2195–2198.
• [13] NARVÁEZ J., CHERWEK D.H., STULTING R.D., WALDRON R., ZIMMERMAN G.J., WESSELS I.F., WARING G.O., Comparing immersion ultrasound with partial coherence interferometry for intraocular lens power calculation, Ophthalmic Surgery, Lasers and Imaging 39(1), 2008, pp. 30–34.
• [14] PACKER M., FINE I.H., HOFFMAN R.S., COFFMAN P.G., BROWN L.K., Immersion A-scan compared with partial coherence interferometry: outcome analysis, Journal of Cataract and Refractive Surgery 28(2), 2002, pp. 239–242.
• [15] KISS B., FINDL O., MENAPACE R., WIRTITSCH M., PETTERNEL V., DREXLER W., RAINER G., GEORGOPOULOS M., HITZENBERGER C.K., FERCHER A.F., Refractive outcome of cataract surgery using partial coherence interferometry and ultrasound biometry: clinical feasibility study of a commercial prototype II, Journal of Cataract and Refractive Surgery 28(2), 2002, pp. 230–234.
• [16] HAIGIS W., LEGE B., MILLER N., SCHNEIDER B., Comparison of immersion ultrasound biometry and partial coherence interferometry for intraocular lens calculation according to Haigis, Graefes Archive for Clinical and Experimental Ophthalmology 238(9), 2000, pp. 765–773.
• [17] OBRAZ J., Ultrazvuk v měřicí technice, 2nd Edition, SNTL 1984, Praha (in Czech).
• [18] BYRNE S.F., GREEN R.L., Ultrasound of the Eye and Orbit, St Luios, Mosby, 1992, pp. 219–220.
• [19] SPENCER G.H., MURTY M.V.R.K., General ray-tracing procedure, Journal of the Optical Society of America 52(6), 1962, pp. 672–678.
• [20] LOTMAR W., Theoretical eye model with aspherics, Journal of the Optical Society of America 61(11), 1971, pp. 1522–1529.
• [21] DRASDO N., FOWLER C.W., Non-linear projection of the retinal image in a wide-angle schematic eye, British Journal of Ophthalmology 58(8), 1974, pp. 709–714.
• [22] KOOIJMAN A.C., Light distribution on the retina of a wide-angle theoretical eye, Journal of the Optical Society of America 73(11), 1983, pp. 1544–1550.
• [23] NAVARRO R., SANTAMARÍA J., BESCÓS J., Accommodation-dependent model of the human eye with aspherics, Journal of Optical Society of America A 2(8), 1985, pp. 1273–1280.
• [24] LIOU H.L., BRENNAN N.A., Anatomically accurate, finite model eye for optical modeling, Journal of Optical Society of America A 14(8), 1997, pp. 1684–1695.
• [25] JIVRAJKA R., SHAMMAS M.C., BOENZI T., SWEARINGEN M., SHAMMAS H.J., Variability of axial length, anterior chamber depth, and lens thickness in the cataractous eye, Journal of Cataract and Refractive Surgery 34(2), 2008, pp. 289–294.
• [26] FALHAR M., ŘEHÁK J., A theoretical model of the human eye based on ultrasound and corneal data, Optica Applicata 39(1), 2009, pp. 195–210.
• [27] KORYNTA J., CENDELÍN J., Teoretické základy bezchybné biometrie, Česká a Slovenská Oftalmologie 51(1), 1995, pp. 44–55 (in Czech).
• [28] NEMETH G., VAJAS A., TSORBATZOGLOU A., KOLOZSVARI B., MODIS L., BERTA A., Assessment and reproducibility of anterior chamber depth measurement with anterior segment optical coherence tomography compared with immersion ultrasonography, Journal of Cataract and Refractive Surgery 33(3), 2007, pp. 443–447.
• [29] LEGE B.A., HAIGIS W., Laser interference biometry versus ultrasound biometry in certain clinical conditions, Graefes Archive for Clinical and Experimental Ophthalmology 242(1), 2004, pp. 8–12.