commonly seen, as are inguinal hernias Ocular abnormalities occur in about three-quarters of patients The most frequent are subluxation of the lenses and myopia Because of the importance of identifying individuals with this disease, a multidisciplinary group of experts produced diagnostic criteria known as the Ghent nosology.198 The 2010 revised Ghent nosology is divided into those with a positive family history and those without a positive family history For those without a positive family history, the definitive diagnosis can be made with aortic root dilation (z-score plus 2 at the sinus of Valsalva or aortic root dissection) and one of the following; ectopia lentis, FBN1 mutations, and/or a systemic score of 7 or greater In the absence of aortic root dilation the diagnosis can be made in the presence of ectopia lentis and an FBN1 mutation known to cause aortic root dilation In the present of a positive family history the diagnosis can be made in the presence of ectopia lentis, systemic score of 7 or greater, or an aortic root z-score of 2 or greater if the patient is above age 20 years, or 3 or greater if the patient is younger than age 20 years (Box 59.1) The addition of the systemic score allows for findings in multiple organ systems to be factored into the diagnostic criteria Table 59.1 Adolescents and children may not meet the criteria If clinical suspicion remains high, this group should still be monitored for aortic root dilation.199 a systemic score calculator with additional diagnostic details can be found at https://www.marfan.org/ FIG 59.3 (A) Typical body habitus of a patient with Marfan syndrome shows how the arm span exceeds the height by more than 5% (B) The positive wrist sign and (C) the positive thumb sign Box 59.1 2010 Revised Ghent Nosology for the Diagnosis of Marfan Syndrome Absence of Family History of Marfan Syndrome Aortic root z-score ≥2 and ectopia lentis Aortic root z-score ≥2 and FBN1 mutation Aortic root z-score ≥2 and systemic score ≥7 Ectopia lentis and an FBN1 mutation with known aortic root dilation Presence of Family History of Marfan Syndrome Ectopia lentis Systemic score ≥7 Aortic root z-score ≥2 if >20 years old and aortic root z-score ≥3 if