In 1942, American physician John K. Taggart and Canadian–American neurosurgeon Arthur Earl Walker detailed the phenomenon extensively, ascribing the potential cause as underdevelopment of the foramina of Luschka and Magendie, now no longer believed to be significant.The term Dandy–Walker syndrome (DWS) was introduced by German psychiatrist Clemens Ernst Benda in 1954; he also used the term Dandy–Walker malformation once. In 1976, Harwood-Nash and Fitz proposed the term Dandy–Walker variant (DWV) for a malformation in which the posterior fossa is not enlarged but the cerebellar vermis is hypoplastic. In 1989, Barkovich et al. proposed the term Dandy–Walker complex (DWC) to include classic DWM and DWV (under type A) plus a third malformation (under type B) in which the cerebellar vermis remains large enough to sit between the fourth ventricle and the cisterna magna, and instead it is mostly the cisterna magna that is enlarged (sometimes diagnosed as "mega cisterna magna"). In 1999, Calabró et al. first used the phrase Dandy–Walker continuum when referring to proposals that a condition known as Blakes pouch cyst falls under the umbrella of the Dandy–Walker complex proposed by Barkovich. These additional terms are mostly discouraged by modern authors due to additional confusion and complexity to the diagnosis of DWM. References
This article incorporates public domain material from the United States Government document: "Dandy-Walker Syndrome Information Page". Further reading
Metry Phaces article in the Journal of Pediatrics, July 2001
E-medicine webpage definition
Dandy–Walker Malformation article from Pan Arab Journal of Neurosurgery


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It may reveal both an excess of white blood cells (leukocytosis) or a decrease (leukopenia), and a low red blood cell count (anemia) and low platelets (thrombocytopenia) can also be commonly seen. A blood film may show leukemic blast cells. Inclusions within the cells called Auer rods, when seen, make the diagnosis highly likely. A definitive diagnosis requires a bone marrow aspiration and biopsy.Bone marrow is examined under light microscopy, as well as flow cytometry, to diagnose the presence of leukemia, to differentiate AML from other types of leukemia (e.g. acute lymphoblastic leukemia), and to provide information about how mature or immature the affected cells are that can assist in classifying the subtype of disease. A sample of marrow or blood is typically also tested for chromosomal abnormalities by routine cytogenetics or fluorescent in situ hybridization. Genetic studies may also be performed to look for specific mutations in genes such as FLT3, nucleophosmin, and KIT, which may influence the outcome of the disease.Cytochemical stains on blood and bone marrow smears are helpful in the distinction of AML from ALL, and in subclassification of AML. The combination of a myeloperoxidase or Sudan black stain and a nonspecific esterase stain will provide the desired information in most cases. The myeloperoxidase or Sudan black reactions are most useful in establishing the identity of AML and distinguishing it from ALL.