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We appreciate the comment by Khan on Bowen and colleagues1Bowen M. Peragallo J.H. Kralik S.F. Poretti A. Huisman T.A.G.M. Soares B.P. Magnetic resonance imaging findings in children with spasmus nutans.J AAPOS. 2017; 21: 127-130Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar and the insight into an unusual form of nystagmus2Khan A.O. Alrashed M. Alkuraya F.S. Cone dystrophy with supranormal rod response in children.Br J Ophthalmol. 2012; 96: 422-426Crossref PubMed Scopus (30) Google Scholar that can be mistaken for spasmus nutans. The particular entity described by Khan is due to KCNV2-related retinopathy.2Khan A.O. Alrashed M. Alkuraya F.S. Cone dystrophy with supranormal rod response in children.Br J Ophthalmol. 2012; 96: 422-426Crossref PubMed Scopus (30) Google Scholar, 3Khan A.O. Recognizing the KCNV2-related phenotype.Ophthalmology. 2013; 120: e79-80Abstract Full Text Full Text PDF PubMed Scopus (7) Google Scholar Several entities can mimic spasmus nutans and may be termed spasmus nutans–like. The findings upon presentation of these children with KCNV2-related retinopathy (intermittent small-amplitude, high-frequency variable nystagmus with torticollis and head shaking) are very similar to spasmus nutans, and distinguishing the two entities without an electroretinogram would be extremely difficult. Other important entities that can mimic spasmus nutans include not only retinal dystrophies such as Bardet-Biedl syndrome,4Gottlob I. Heibling A. Nystagmus mimicking spasmus nutans as the presenting sign of Bardet-Biedl syndrome.Am J Ophthalmol. 1999; 128: 770-772Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar achromatopsia,5Smith D.E. Fitzgerald K. Stass-Isern M. et al.Electroretinography is necessary for spasmus nutans diagnosis.Pediatr Neurol. 2000; 23: 33-36Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar and congenital stationary night blindness6Lambert S.R. Newman N.J. Retinal disease masquerading as spasmus nutans.Neurology. 1993; 43: 1607-1609Crossref PubMed Google Scholar but also optic pathway gliomas,7Kelly T.W. Optic glioma presenting as spasmus nutans.Pediatrics. 1970; 45: 295-296PubMed Google Scholar as mentioned by Bowen and colleagues,1Bowen M. Peragallo J.H. Kralik S.F. Poretti A. Huisman T.A.G.M. Soares B.P. Magnetic resonance imaging findings in children with spasmus nutans.J AAPOS. 2017; 21: 127-130Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar although an occurrence of optic pathway glioma was not found in this cohort. We hope that the insights into spasmus nutans and spasmus nutans–like nystagmus presented in our article and by Khan will improve the approach to patients who present with these symptoms. Magnetic resonance imaging findings in children with spasmus nutansJournal of American Association for Pediatric Ophthalmology and Strabismus {JAAPOS}Vol. 21Issue 4PreviewTo the Editor: I read with interest the article by Bowen and colleagues1 regarding magnetic imaging findings in children with spasmus nutans. The authors correctly mention that spasmus nutans may mimic underlying retinal pathology. I would like to highlight that there is one retinopathy in particular that tends to be mistaken as spasmus nutans in children—“cone dystrophy with supranormal rod response” (KCNV2-related retinopathy).2 This form of retinal dystrophy, one of the few with a pathognomonic electroretinogram, seems more common on the Arabian Peninsula and, in my experience, is the most common cause of a spasmus nutans–like picture in the region. Full-Text PDF