{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T23:29:02Z","timestamp":1789774142212,"version":"4.0.1"},"reference-count":28,"publisher":"Springer Science and Business Media LLC","issue":"12","license":[{"start":{"date-parts":[[2023,10,20]],"date-time":"2023-10-20T00:00:00Z","timestamp":1697760000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2023,10,20]],"date-time":"2023-10-20T00:00:00Z","timestamp":1697760000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100009827","name":"Alexandria University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100009827","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Int Ophthalmol"],"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Purpose<\/jats:title>\n                <jats:p>The purpose of this prospective study was to evaluate the effect of combined photorefractive keratectomy (PRK) and corneal collagen cross-linking (CXL) on intraocular pressure (IOP) in patients with keratoconus (KC).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>We included 64 eyes of 34 patients (19 males and 15 females; age: 19-40y) with stages 1\u20132 keratoconus which had undergone combined wavefront-optimized photorefractive keratectomy and corneal collagen cross linking. Two other groups of patients were added as controls: the PRK group including 110 eyes of 57 patients (23 males and 34 females; age: 18-44y) which had undergone wavefront-optimized photorefractive keratectomy for myopic refractive errors, and the CXL group including 36 eyes of 23 patients (14 males and 9 females; age: 12-38y) with keratoconus, not filling the inclusion criteria for combined PRK and CXL, which had undergone corneal collagen cross-linking. IOP was recorded preoperatively and postoperatively at 3, 6 and 12\u00a0months follow-up visits.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Preoperative IOP in both CXL (12.1\u2009\u00b1\u20092.53\u00a0mmHg) and PRK\u2009+\u2009CXL (13.2\u2009\u00b1\u20092.50\u00a0mmHg) groups was significantly lower than PRK group (15.8\u2009\u00b1\u20093.10\u00a0mmHg) (F\u2009=\u200930.505, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001). At 3\u00a0months postoperatively, IOP showed no statistically significant difference between the three studied groups (F\u2009=\u20091.821, <jats:italic>p<\/jats:italic>\u2009=\u20090.164). At 6\u00a0months postoperatively, IOP in the CXL group (14.6\u2009\u00b1\u20092.64\u00a0mmHg) was significantly higher than both PRK (13.4\u2009\u00b1\u20092.27\u00a0mmHg) and PRK\u2009+\u2009CXL (13.3\u2009\u00b1\u20092.62\u00a0mmHg) groups (F\u2009=\u20093.721, <jats:italic>p<\/jats:italic>\u2009=\u20090.026). At 12\u00a0months postoperatively, IOP in the CXL group (14.3\u2009\u00b1\u20092.69\u00a0mmHg) was significantly higher than the PRK group (13.2\u2009\u00b1\u20092.23\u00a0mmHg) and was higher than PRK\u2009+\u2009CXL group (13.3\u2009\u00b1\u20092.59\u00a0mmHg) although not statistically significant (F\u2009=\u20093.393, <jats:italic>p<\/jats:italic>\u2009=\u20090.035).<\/jats:p>\n                <jats:p>Regarding the percent of change from preoperative IOP, a statistically significant difference between the three studied groups was detected at 3, 6 and 12\u00a0months postoperatively (H\u2009=\u2009117.459, 109.303, 122.694 respectively, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001). The median percent of change from preoperative IOP in the PRK group was \u221216.7%, \u221215%, and \u221216.7%, in the CXL group was\u2009+\u200914.3%,\u2009+\u200919.4%, and\u2009+\u200919.1%, while in PRK\u2009+\u2009CXL group was 0% at 3, 6 and 12\u00a0months postoperatively. (Post-hoc power analysis 75%).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Combined PRK and CXL in patients with KC shows no significant effect on IOP, in contrast to either procedure performed separately.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s10792-023-02886-w","type":"journal-article","created":{"date-parts":[[2023,10,20]],"date-time":"2023-10-20T06:02:26Z","timestamp":1697781746000},"page":"4837-4849","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Intraocular pressure after combined photorefractive keratectomy and corneal collagen cross-linking for keratoconus"],"prefix":"10.1007","volume":"43","author":[{"given":"Karim Mahmoud","family":"Nabil","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmed Abdel Karim","family":"Elmassry","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silas","family":"Ntakarusho","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amr Ahmed","family":"Said","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2023,10,20]]},"reference":[{"issue":"12","key":"2886_CR1","doi-asserted-by":"publisher","first-page":"1929","DOI":"10.18240\/ijo.2019.12.16","volume":"12","author":"MM Al-Mohaimeed","year":"2019","unstructured":"Al-Mohaimeed MM (2019) Combined corneal CXL and photorefractive keratectomy for treatment of keratoconus: a review. Int J Ophthalmol 12(12):1929\u20131938","journal-title":"Int J Ophthalmol"},{"issue":"9","key":"2886_CR2","first-page":"S812","volume":"25","author":"AJ Kanellopoulos","year":"2009","unstructured":"Kanellopoulos AJ (2009) Comparison of sequential vs same-day simultaneous collagen cross-linking and topography-guided PRK for treatment of keratoconus. J Refract Surg 25(9):S812\u2013S818","journal-title":"J Refract Surg"},{"issue":"1","key":"2886_CR3","first-page":"48","volume":"11","author":"AM Al-Amri","year":"2018","unstructured":"Al-Amri AM (2018) 5-year follow-up of combined non-topography guided photorefractive keratectomy and corneal collagen cross linking for keratoconus. Int J Ophthalmol 11(1):48\u201352","journal-title":"Int J Ophthalmol"},{"issue":"4","key":"2886_CR4","doi-asserted-by":"publisher","first-page":"235","DOI":"10.1016\/j.joco.2017.07.003","volume":"29","author":"M Mohammadpour","year":"2017","unstructured":"Mohammadpour M, Masoumi A, Mirghorbani M, Shahraki K, Hashemi H (2017) Updates on corneal collagen cross-linking: indications, techniques and clinical outcomes. J Curr Ophthalmol 29(4):235\u2013247","journal-title":"J Curr Ophthalmol"},{"key":"2886_CR5","doi-asserted-by":"publisher","first-page":"5494","DOI":"10.1167\/iovs.06-1479","volume":"48","author":"T Romppainen","year":"2007","unstructured":"Romppainen T, Bachmann LM, Kaufmann C, Kniestedt C, Mrochen M, Thiel MA (2007) Effect of riboflavin-UVA-induced collagen cross-linking on intraocular pressure measurement. Invest Ophthalmol Vis Sci 48:5494\u20135498","journal-title":"Invest Ophthalmol Vis Sci"},{"issue":"10","key":"2886_CR6","doi-asserted-by":"publisher","first-page":"1724","DOI":"10.1016\/j.jcrs.2010.05.016","volume":"36","author":"GD Kymionis","year":"2010","unstructured":"Kymionis GD, Grentzelos MA, Kounis GA, Portaliou DM, Detorakis ET, Magarakis M, Karampatakis VE, Pallikaris IG (2010) Intraocular pressure measurements after corneal collagen crosslinking with riboflavin and ultraviolet A in eyes with keratoconus. J Cataract Refract Surg 36(10):1724\u20131727","journal-title":"J Cataract Refract Surg"},{"issue":"3","key":"2886_CR7","doi-asserted-by":"publisher","first-page":"471","DOI":"10.1016\/j.ophtha.2014.09.033","volume":"122","author":"JM Schallhorn","year":"2015","unstructured":"Schallhorn JM, Schallhorn SC, Ou Y (2015) Factors that influence intraocular pressure changes after myopic and hyperopic LASIK and photorefractive keratectomy: a large population study. Ophthalmology 122(3):471\u2013479","journal-title":"Ophthalmology"},{"issue":"4","key":"2886_CR8","doi-asserted-by":"publisher","first-page":"459","DOI":"10.1136\/bjophthalmol-2013-304132","volume":"98","author":"K Kamiya","year":"2014","unstructured":"Kamiya K, Ishii R, Shimizu K, Igarashi A (2014) Evaluation of corneal elevation, pachymetry and keratometry in keratoconic eyes with respect to the stage of Amsler-Krumeich classification. Br J Ophthalmol 98(4):459\u2013463","journal-title":"Br J Ophthalmol"},{"issue":"3","key":"2886_CR9","doi-asserted-by":"publisher","first-page":"253","DOI":"10.1097\/ICO.0B013E31823D1EE0","volume":"31","author":"R Ishii","year":"2012","unstructured":"Ishii R, Kamiya K, Igarashi A, Shimizu K, Utsumi Y, Kumanomido T (2012) Correlation of corneal elevation with severity of keratoconus by means of anterior and posterior topographic analysis. Cornea 31(3):253\u2013258","journal-title":"Cornea"},{"issue":"5","key":"2886_CR10","doi-asserted-by":"publisher","first-page":"357","DOI":"10.1016\/j.clae.2015.04.001","volume":"38","author":"I Toprak","year":"2015","unstructured":"Toprak I, Yaylali V, Yildirim C (2015) A combination of topographic and pachymetric parameters in keratoconus diagnosis. Cont Lens Anterior Eye 38(5):357\u2013362","journal-title":"Cont Lens Anterior Eye"},{"issue":"8","key":"2886_CR11","doi-asserted-by":"publisher","first-page":"1371","DOI":"10.1016\/j.jcrs.2007.04.021","volume":"33","author":"D Ortiz","year":"2007","unstructured":"Ortiz D, Pi\u00f1ero D, Shabayek MH, Arnalich-Montiel F, Ali\u00f3 JL (2007) Corneal biomechanical properties in normal, post-laser in situ keratomileusis, and keratoconic eyes. J Cataract Refract Surg 33(8):1371\u20131375","journal-title":"J Cataract Refract Surg"},{"issue":"2","key":"2886_CR12","doi-asserted-by":"publisher","first-page":"233","DOI":"10.1111\/cxo.12016","volume":"96","author":"PG Firat","year":"2013","unstructured":"Firat PG, Orman G, Doganay S, Demirel S (2013) Influence of corneal parameters in keratoconus on IOP readings obtained with different tonometers. Clin Exp Optom 96(2):233\u2013237","journal-title":"Clin Exp Optom"},{"issue":"5","key":"2886_CR13","doi-asserted-by":"publisher","first-page":"334","DOI":"10.5455\/medarh.2015.69.334-338","volume":"69","author":"SS Kasumovic","year":"2015","unstructured":"Kasumovic SS, Mavija M, Kasumovic A, Lepara O, Duric-Colic B, Cabric E, Muhamedagic L, Sakovic-Racic A, Jankov M (2015) Intraocular Pressure Measurements Referring to the Corneal Thickness in Keratoconic Eyes After Corneal Crosslinking with Riboflavin and Ultraviolet A. Med Arch 69(5):334\u2013338","journal-title":"Med Arch"},{"issue":"12","key":"2886_CR14","doi-asserted-by":"publisher","first-page":"8377","DOI":"10.1167\/iovs.14-15348","volume":"55","author":"N Morishige","year":"2014","unstructured":"Morishige N, Shin-Gyou-Uchi R, Azumi H, Ohta H, Morita Y, Yamada N, Kimura K, Takahara A, Sonoda KH (2014) Quantitative analysis of collagen lamellae in the normal and keratoconic human cornea by second harmonic generation imaging microscopy. Invest Ophthalmol Vis Sci 55(12):8377\u20138385","journal-title":"Invest Ophthalmol Vis Sci"},{"issue":"8","key":"2886_CR15","doi-asserted-by":"publisher","first-page":"767","DOI":"10.1111\/aos.12811","volume":"93","author":"JH Mathew","year":"2015","unstructured":"Mathew JH, Goosey JD, S\u00f6derberg PG, Bergmanson JP (2015) Lamellar changes in the keratoconic cornea. Acta Ophthalmol 93(8):767\u2013773","journal-title":"Acta Ophthalmol"},{"key":"2886_CR16","doi-asserted-by":"publisher","first-page":"97","DOI":"10.1006\/exer.1997.0410","volume":"66","author":"E Spoerl","year":"1998","unstructured":"Spoerl E, Huhle M, Seiler T (1998) Induction of cross-links in corneal tissue. Exp Eye Res 66:97\u2013103","journal-title":"Exp Eye Res"},{"issue":"5","key":"2886_CR17","doi-asserted-by":"publisher","first-page":"620","DOI":"10.1016\/S0002-9394(02)02220-1","volume":"135","author":"G Wollensak","year":"2003","unstructured":"Wollensak G, Spoerl E, Seiler T (2003) Riboflavin\/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol 135(5):620\u2013627","journal-title":"Am J Ophthalmol"},{"issue":"7","key":"2886_CR18","first-page":"2402","volume":"63","author":"SC Kaufman","year":"2022","unstructured":"Kaufman SC, Liaboe C, Meduri A (2022) Alterations in measured intraocular pressure following corneal collagen cross linking. Invest Ophthalmol Vis Sci 63(7):2402-A0205","journal-title":"Invest Ophthalmol Vis Sci"},{"issue":"5","key":"2886_CR19","doi-asserted-by":"publisher","first-page":"503","DOI":"10.1097\/01.ico.0000105827.85025.7f","volume":"23","author":"G Wollensak","year":"2004","unstructured":"Wollensak G, Wilsch M, Spoerl E, Seiler T (2004) Collagen fiber diameter in the rabbit cornea after collagen crosslinking by riboflavin\/UVA. Cornea 23(5):503\u2013507","journal-title":"Cornea"},{"issue":"1","key":"2886_CR20","doi-asserted-by":"publisher","first-page":"10","DOI":"10.15406\/aovs.2022.12.00409","volume":"12","author":"N Waheed","year":"2022","unstructured":"Waheed N, Kamal M, Azam S, Priyanka P, Ali H, Kiran A, Talpur AH (2022) Effect of corneal cross linkage (CXL) on intraocular pressure (IOP) measurements in keratoconus patients. Advances in Ophthalmology & Visual System 12(1):10\u201312","journal-title":"Advances in Ophthalmology & Visual System"},{"key":"2886_CR21","doi-asserted-by":"publisher","first-page":"2921","DOI":"10.2147\/OPTH.S318317","volume":"15","author":"KA Beckman","year":"2021","unstructured":"Beckman KA (2021) Epithelium-on corneal collagen cross-linking with hypotonic riboflavin solution in progressive keratoconus. Clin Ophthalmol 15:2921\u20132932","journal-title":"Clin Ophthalmol"},{"issue":"8","key":"2886_CR22","doi-asserted-by":"publisher","first-page":"1150","DOI":"10.1016\/j.ophtha.2020.12.023","volume":"128","author":"S Nath","year":"2021","unstructured":"Nath S, Shen C, Koziarz A, Banfield L, Nowrouzi-Kia B, Fava MA, Hodge WG (2021) Transepithelial versus epithelium-off corneal collagen cross-linking for corneal ectasia: a systematic review and meta-analysis. Ophthalmology 128(8):1150\u20131160","journal-title":"Ophthalmology"},{"key":"2886_CR23","first-page":"5592195","volume":"2021","author":"CC Chou","year":"2021","unstructured":"Chou CC, Shih PJ, Lin HC, Chen JP, Yen JY, Wang IJ (2021) Changes in intraocular pressure after transepithelial photorefractive keratectomy and femtosecond laser in situ keratomileusis. J Ophthalmol 2021:5592195","journal-title":"J Ophthalmol"},{"issue":"12","key":"2886_CR24","doi-asserted-by":"publisher","first-page":"2757","DOI":"10.4103\/ijo.IJO_1841_20","volume":"68","author":"VP Kankariya","year":"2020","unstructured":"Kankariya VP, Dube AB, Grentzelos MA, Kontadakis GA, Diakonis VF, Petrelli M, Kymionis GD (2020) Corneal cross-linking (CXL) combined with refractive surgery for the comprehensive management of keratoconus: CXL plus. Indian J Ophthalmol 68(12):2757\u20132772","journal-title":"Indian J Ophthalmol"},{"key":"2886_CR25","doi-asserted-by":"publisher","first-page":"88","DOI":"10.3928\/1081597X-20140120-03","volume":"30","author":"J Kanellopoulos","year":"2014","unstructured":"Kanellopoulos J, Asimellis G (2014) Keratoconus management: long-term stability of topography-guided normalization combined with high fluence CXL stabilization (the Athens Protocol). J Refract Surg 30:88\u201393","journal-title":"J Refract Surg"},{"key":"2886_CR26","doi-asserted-by":"crossref","unstructured":"Iqbal M, Elmassry A, Tawfik A, Elgharieb ME, El Deen Al Nahrawy OM, Soliman AH, Saad HA, Ibrahim Elzembely HA, Saeed AM, Mohammed OA, Kamel AG, El Saman IS. Evaluation of the Effectiveness of Cross-Linking Combined With Photorefractive Keratectomy for Treatment of Keratoconus. Cornea. 2018 ;37(9):1143\u20131150.","DOI":"10.1097\/ICO.0000000000001663"},{"issue":"14","key":"2886_CR27","doi-asserted-by":"crossref","first-page":"251584142210833","DOI":"10.1177\/25158414221083362","volume":"23","author":"G De Rosa","year":"2022","unstructured":"De Rosa G, Rossi S, Santamaria C, Boccia R, De Rosa L, D\u2019Alterio FM, Simonelli F (2022) Combined photorefractive keratectomy and corneal collagen cross-linking for treatment of keratoconus: a 2-year follow-up study. Ther Adv Ophthalmol 23(14):25158414221083360","journal-title":"Ther Adv Ophthalmol"},{"issue":"4","key":"2886_CR28","doi-asserted-by":"publisher","first-page":"e623","DOI":"10.1111\/aos.13986","volume":"97","author":"M Iqbal","year":"2019","unstructured":"Iqbal M, Elmassry A, Tawfik A, Elgharieb M, Nagy K, Soliman A, Saad H, Tawfik T, Ali O, Gad A, El Saman I, Radwan A, Elzembely H, Abou Ali A, Fawzy O (2019) Standard cross-linking versus photorefractive keratectomy combined with accelerated cross-linking for keratoconus management: a comparative study. Acta Ophthalmol 97(4):e623\u2013e631","journal-title":"Acta Ophthalmol"}],"container-title":["International Ophthalmology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10792-023-02886-w.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s10792-023-02886-w\/fulltext.html","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10792-023-02886-w.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,12,15]],"date-time":"2023-12-15T15:10:50Z","timestamp":1702653050000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s10792-023-02886-w"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,10,20]]},"references-count":28,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2023,12]]}},"alternative-id":["2886"],"URL":"https:\/\/doi.org\/10.1007\/s10792-023-02886-w","relation":{},"ISSN":["1573-2630"],"issn-type":[{"value":"1573-2630","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,10,20]]},"assertion":[{"value":"16 May 2023","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"27 September 2023","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"20 October 2023","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}},{"value":"None.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflict of interest"}},{"value":"All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and\/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"Informed consent to participate in the study was obtained from all individual participants included in the study.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Informed consent"}},{"value":"Informed consent to publish the results of the study was obtained from all individual participants included in the study.","order":6,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent to publish"}}]}}