{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T17:35:57Z","timestamp":1787160957330,"version":"build-2736575974"},"reference-count":55,"publisher":"Georg Thieme Verlag KG","issue":"01","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Klin Monbl Augenheilkd"],"published-print":{"date-parts":[[2023,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Keratoconus (KC) must be distinguished from other corneal ectatic diseases and thinning disorders for stage-appropriate and suitable management of each condition. The most relevant corneal\n\t\t\t\t\tpathologies that may imitate the tomographic KC pattern are pellucid marginal degeneration (PMD), keratoglobus, posterior keratoconus, and Fuchs-Terrien marginal degeneration (FTMD). In\n\t\t\t\t\tmoderate cases of KC, differentiation is typically possible using slit lamp examination and corneal tomography with evaluation of the location of the corneal thinning region. In early cases,\n\t\t\t\t\thowever, differential diagnosis may be more challenging since the cornea may look relatively normal. In severe cases, the extended area of corneal thinning also complicates differentiation.\n\t\t\t\t\tBiomicroscopic findings cannot always give all the information needed to distinguish KC from related ectatic corneal conditions. The aim of this work is to discuss contemporary techniques\n\t\t\t\t\tand findings to assist physicians to identify the correct diagnosis. Corneal topography has been used in recent decades as the main tool for imaging in ectatic corneal diseases. Moreover,\n\t\t\t\t\tScheimpflug cameras (corneal tomographers), which analyze both anterior and posterior corneal surfaces, curvatures, pachymetry, elevation data, higher order aberrations, Fourier analysis of\n\t\t\t\t\tkeratometric data, and corneal density have become the most promising tools for diagnosis and follow-up of ectatic diseases. A noninvasive air pulse tonometer in conjunction with an\n\t\t\t\t\tultrahigh-speed Scheimpflug camera complements tomographic findings by analyzing biomechanical corneal properties. \u0391 confocal microscopy system, which is a novel clinical technique for the\n\t\t\t\t\tstudy of corneal cellular structure, could contribute effectively in the same direction. Moreover, anterior segment optical coherence tomography (AS-OCT) creates cross-sections, which can be\n\t\t\t\t\tgenerated into a three-dimensional structure to produce corneal epithelial thickness (ET) measurements. ET mapping is increasingly recognized as a sensitive tool for the diagnosis of ocular\n\t\t\t\t\tsurface disorders. Combining information of all these systems could lead to a more effective identification and differential diagnosis of ectatic corneal disorders.<\/jats:p>","DOI":"10.1055\/a-1920-6929","type":"journal-article","created":{"date-parts":[[2022,8,8]],"date-time":"2022-08-08T18:49:20Z","timestamp":1659984560000},"page":"57-72","source":"Crossref","is-referenced-by-count":12,"title":["Differential Diagnosis of Keratoconus Based on New Technologies"],"prefix":"10.1055","volume":"240","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8415-1233","authenticated-orcid":false,"given":"Haris","family":"Sideroudi","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Saarland University Medical Center and Saarland University Faculty of Medicine, Homburg\/Saar, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0423-3624","authenticated-orcid":false,"given":"Elias","family":"Flockerzi","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Saarland University Medical Center and Saarland University Faculty of Medicine, Homburg\/Saar, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9701-8204","authenticated-orcid":false,"given":"Berthold","family":"Seitz","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Saarland University Medical Center and Saarland University Faculty of Medicine, Homburg\/Saar, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2022,11,27]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"297","DOI":"10.1016\/s0039-6257(97)00119-7","article-title":"Keratoconus","volume":"42","author":"Y S Rabinowitz","year":"1998","journal-title":"Surv Ophthalmol"},{"key":"ref2","first-page":"931","volume-title":"Stromal Degenerations","author":"O Shakir","year":"2018"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"1109","DOI":"10.1097\/ICO.0b013e31817f815a","article-title":"Keratoconus clinical findings according to different age and gender groups","volume":"27","author":"A Ertan","year":"2008","journal-title":"Cornea"},{"key":"ref4","doi-asserted-by":"publisher","first-page":"382","DOI":"10.4103\/0301-4738.116054","article-title":"Epidemiology of keratoconus","volume":"61","author":"N S Gokhale","year":"2013","journal-title":"Indian J Ophthalmol"},{"key":"ref5","doi-asserted-by":"publisher","first-page":"267","DOI":"10.1016\/0002-9394(86)90817-2","article-title":"A 48-year clinical and epidemiologic study of keratoconus","volume":"101","author":"R H Kennedy","year":"1986","journal-title":"Am J Ophthalmol"},{"key":"ref6","doi-asserted-by":"publisher","first-page":"1069","DOI":"10.1136\/bjophthalmol-2020-316789","article-title":"Keratoconus staging by decades: a baseline ABCD classification of 1000 patients in the Homburg Keratoconus Center","volume":"105","author":"E Flockerzi","year":"2021","journal-title":"Br J Ophthalmol"},{"key":"ref7","doi-asserted-by":"crossref","first-page":"1217","DOI":"10.1001\/archopht.1978.03910060051009","article-title":"Pellucid marginal corneal degeneration","volume":"96","author":"J H Krachmer","year":"1978","journal-title":"Arch Ophthalmol"},{"key":"ref8","first-page":"873","article-title":"Ein Beitrag zur Kenntnis des Keratotorus","volume":"148","author":"I Stankovic","year":"1966","journal-title":"Klin Monbl Augenheilkd"},{"key":"ref9","first-page":"47","article-title":"Su di un case di degenerazione marginale della cornea \u2013 varieta inferiore pellucida \u2013 studio clinic ed istologico","volume":"88","author":"G Zucchini","year":"1962","journal-title":"Ann Ottalmol Clin Oculitl"},{"key":"ref10","doi-asserted-by":"publisher","first-page":"385","DOI":"10.1136\/bjo.73.5.385","article-title":"Keratoglobus in Rubinstein-Taybi syndrome","volume":"73","author":"M E Nelson","year":"1989","journal-title":"Br J Ophthalmol"},{"key":"ref11","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1016\/0002-9394(77)90621-3","article-title":"Keratoglobus and blue sclera","volume":"83","author":"A W Biglan","year":"1977","journal-title":"Am J Ophthalmol"},{"key":"ref12","doi-asserted-by":"publisher","first-page":"1029","DOI":"10.1001\/archophthalmol.2009.184","article-title":"Histopathologic and immunohistochemical studies of keratoglobus","volume":"127","author":"B Meghpara","year":"2009","journal-title":"Arch Ophthalmol"},{"key":"ref13","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1007\/978-94-009-8662-6_18","article-title":"Myopia and scleral stress","volume":"28","author":"E S Perkins","year":"1981","journal-title":"Doc Ophthalmol Proc Series"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"30","DOI":"10.1136\/bjo.16.1.30","article-title":"Two Rare Corneal Conditions: I. 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