Morning glory disk anomaly—more than meets the eye
2009; Elsevier BV; Volume: 13; Issue: 4 Linguagem: Inglês
10.1016/j.jaapos.2009.05.015
ISSN1528-3933
Autores Tópico(s)Ocular Disorders and Treatments
ResumoThree case reports of morning glory disk anomaly in this issue of Journal of AAPOS illustrate peculiar and unique clinical aspects or associations of this uncommon optic nerve malformation.1Chew F. Visvaraja S. 47XYY and morning glory syndrome—A unique association.J AAPOS. 2009; 13: 406-407Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar, 2Choudhry N. Ramasubramanian A. Shields C.L. Brown G. Shields J.A. Spontaneous resolution of retinal detachment in morning glory disk anomaly.J AAPOS. 2009; (In press)PubMed Google Scholar, 3Loo J.E. Kim K.H. Park H.J. Lee S.J. Jea S.Y. Morning glory disk anomaly: A computerized analysis of contractile movements with implications for pathogenesis.J AAPOS. 2009; 13: 403-405Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar Although it had been described previously,4Handman M. Erbliche, vermutlich angeborene zentrale gliose Entartung des Sehnerven mit besonderer Beteiligung der Zentralgefasse.Klin Montasbl Augenheilkd. 1929; 83: 145Google Scholar, 5Pedler C. Unusual coloboma of the optic nerve entrance.Br J Ophthalmol. 1961; 45: 803-807Crossref PubMed Scopus (48) Google Scholar the clinical features of morning glory disk anomaly were delineated in 1970 by Kindler,6Kindler P. Morning glory syndrome: Unusual congenital optic disk anomaly.Am J Ophthalmol. 1970; 69: 376-384Abstract Full Text PDF PubMed Scopus (203) Google Scholar who so named the condition on account of its resemblance to the morning glory flower. Based on 10 patients, Kindler defined morning glory disk anomaly as an enlarged optic disk with a funnel-shaped excavated peripapillary region surrounded by a wide, elevated annulus of chorioretinal pigment, central white tissue, and retinal vessels appearing on the edge of the disk.6Kindler P. Morning glory syndrome: Unusual congenital optic disk anomaly.Am J Ophthalmol. 1970; 69: 376-384Abstract Full Text PDF PubMed Scopus (203) Google Scholar The degree of disk excavation, the extent of hyaloid system remnants, and the peripapillary pigment changes are variable.7Traboulsi E.I. O'Neill J.F. The spectrum in the morphology of the so-called "morning glory disc anomaly.".J Pediatr Ophthalmol Strabismus. 1988; 25: 93-98PubMed Google Scholar The retinal blood vessels that emerge from the disk extend radially rather than in an arcuate pattern.4Handman M. Erbliche, vermutlich angeborene zentrale gliose Entartung des Sehnerven mit besonderer Beteiligung der Zentralgefasse.Klin Montasbl Augenheilkd. 1929; 83: 145Google Scholar, 7Traboulsi E.I. O'Neill J.F. The spectrum in the morphology of the so-called "morning glory disc anomaly.".J Pediatr Ophthalmol Strabismus. 1988; 25: 93-98PubMed Google Scholar, 8Pollock S. The morning glory disc anomaly: Contractile movement, classification, and embryogenesis.Doc Ophthalmol. 1987; 65: 439-460Crossref PubMed Scopus (85) Google Scholar The anomaly is usually unilateral, and there is no family history of similar occurrences. Bilateral cases have been rarely reported.9Beyer W.B. Quencer R.M. Osher R.H. Morning glory syndrome: A functional analysis including fluorescein angiography, ultrasonography, and computerized tomography.Ophthalmology. 1982; 89: 1362-1367Abstract Full Text PDF PubMed Scopus (64) Google Scholar, 10Loddenkemper T. Friedman N.R. Ruggieri P.M. Marcotty A. Sears J. Traboulsi E.I. Pituitary stalk duplication in association with moya moya disease and bilateral morning glory disc anomaly—Broadening the clinical spectrum of midline defects.J Neurol. 2008; 255: 885-890Crossref PubMed Scopus (15) Google Scholar Lee and Traboulsi11Lee B. Traboulsi E.I. Morning glory disk anomaly revisited.Ophthalm Genet. 2008; 29: 47-52Crossref PubMed Scopus (53) Google Scholar have recently published an extensive review of the clinical aspects of the morning glory disk anomaly. The optic nerve develops along the path of the optic stalk that connects the developing globe to the developing forebrain.12Cook C. Sulik K. Wright K.W. Embryology.in: Wright K.W. Spiegel P.H. Pediatric Ophthalmology and Strabismus. 2nd ed. Spinger-Verlag, New York2003: 3-38Crossref Google Scholar Signals from the surrounding mesenchyme as well as a very delicate balance and well-orchestrated expression of a number of genes determine the organization of the structures that make up the nerve.13Evans A.L. Gage P.J. Expression of the homeobox gene Pitx2 in neural crest is required for optic stalk and ocular anterior segment development.Hum Mol Genet. 2005; 14: 3347-3359Crossref PubMed Scopus (139) Google Scholar Interference with the normal fetal developmental processes that guide the formation of the optic nerve proper or its surrounding and supporting structures results in congenital malformations, some of which occur with abnormalities of the brain and its vasculature or of distal organs in the context of distinct syndromes. The embryologic basis of morning glory disk anomaly is unclear. Although the exceptional, bilateral cases may be genetically determined, a stochastic process could be the cause of the much more common unilateral cases. Morning glory disk anomaly may be the result of a defect in the formation of the posterior sclera with secondary herniation of neural tissue and interference with resorption of primary hyaloidal elements. The association of midline central nervous system and craniofacial anomalies suggests a defect in midline signaling and induction during development. Given the association with moyamoya disease and the abnormal vascular patterns observed in morning glory syndrome, a defect in vascular patterning could also play a role. Chew and Visvaraja1Chew F. Visvaraja S. 47XYY and morning glory syndrome—A unique association.J AAPOS. 2009; 13: 406-407Abstract Full Text Full Text PDF PubMed Scopus (8) Google Scholar report a patient with 47,XYY and bilateral morning glory disk anomaly, accompanied by hypertelorism and pituitary dysfunction. The bilaterality of the anomaly in this patient strongly supports an underlying genetic mutation in this case, perhaps the duplication of a gene on the Y chromosome. The involvement of midline brain structures in this patient is reminiscent of a case recently reported by Loddenkemper and colleagues.10Loddenkemper T. Friedman N.R. Ruggieri P.M. Marcotty A. Sears J. Traboulsi E.I. Pituitary stalk duplication in association with moya moya disease and bilateral morning glory disc anomaly—Broadening the clinical spectrum of midline defects.J Neurol. 2008; 255: 885-890Crossref PubMed Scopus (15) Google Scholar The latter female patient had bilateral morning glory disk anomaly, duplication of the pituitary stalk, and bilateral moyamoya disease of the carotid circulation. I am surprised that, despite several recent articles emphasizing the importance of screening patients with morning glory disk anomaly for moyamoya disease, none of the 3 patients in the reports in this issue of the Journal had magnetic resonance angiographic or other studies to check on the patency and caliber of the carotid circulation or for moyamoya disease, which takes its name from the Japanese for "cloud of smoke"—describing a network of small-vessel anastomoses near the circle of Willis in association with stenosis or occlusion of the distal internal carotid arteries. Brain ischemia due to the stenosis or occlusion of the internal carotid artery leads to the collateral vascular network in the basal ganglia region. Vascular abnormalities of the brain are present in up to 40% of patients with morning glory disk anomaly14Lenhart P.D. Lambert S.R. Newman N.J. Biousse V. Traboulsi E.I. Hutchinson A.K. et al.Intracranial vascular anomalies in patients with morning glory disk anomaly.Am J Ophthalmol. 2006; 142: 644-650Abstract Full Text Full Text PDF PubMed Scopus (46) Google Scholar and could result in either significant morbidity or, as I suspect but have not yet been able to prove, mortality from cerebrovascular accidents. Most reported cases of morning glory disk anomaly have been in children. It is possible that some patients do not reach adulthood as a result of cerebrovascular accidents from associated vascular anomalies. Intracranial vascular dysgenesis may be the common denominator in patients with moyamoya disease and morning glory disk anomaly in the setting of midline abnormalities. Patients with moyamoya disease may benefit from surgical bypass procedures.15Scott R.M. Smith E.R. Moyamoya disease and moyamoya syndrome.N Engl J Med. 2009; 360: 1226-1237Crossref PubMed Scopus (1027) Google Scholar The development of retinal detachment in patients with morning glory disk anomaly is well recognized, and the presence of a unilateral total serous retinal detachment in a baby is very suggestive of an underlying morning glory disk anomaly. Choudhry and colleagues2Choudhry N. Ramasubramanian A. Shields C.L. Brown G. Shields J.A. Spontaneous resolution of retinal detachment in morning glory disk anomaly.J AAPOS. 2009; (In press)PubMed Google Scholar bring to our attention reports of rhegmatogenous retinal detachment in morning glory disk anomaly from small tears at the edge of the malformation that could be visualized with optical coherence tomography.16Ho T.C. Tsai P.C. Chen M.S. Lin L.L. Optical coherence tomography in the detection of retinal break and management of retinal detachment in morning glory syndrome.Acta Ophthalmol Scand. 2006; 84: 225-227Crossref PubMed Scopus (25) Google Scholar The success of retinal reattachment surgery depends critically on the identification of any associated retinal tears, as opposed to a pure serous detachment presumably from a communication between the subretinal and subarachnoid spaces. The latter may indeed subside spontaneously, as Choudhry and colleagues2Choudhry N. Ramasubramanian A. Shields C.L. Brown G. Shields J.A. Spontaneous resolution of retinal detachment in morning glory disk anomaly.J AAPOS. 2009; (In press)PubMed Google Scholar report. Hyperpigmented irregular demarcation lines in the posterior pole of patients with morning glory disk anomaly indicate prior spontaneously resolved serous detachments. The case report by Loo and colleagues3Loo J.E. Kim K.H. Park H.J. Lee S.J. Jea S.Y. Morning glory disk anomaly: A computerized analysis of contractile movements with implications for pathogenesis.J AAPOS. 2009; 13: 403-405Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar illustrates a very peculiar phenomenon in eyes with morning glory disk anomaly, namely, what appear to be contractions of the posterior scleral defect and its contents. It is unfortunate that the authors were not able to perform optical coherence tomography on this patient and study variation in subretinal fluid content in the disk area. While the contraction of muscle elements in the walls of the morning glory disk anomaly is an attractive theory for the pathogenesis of the observed variation in size of the posterior defect, variation in height of a shallow retinal separation within the cavitary malformation could result in the appearance of cyclical variation in size of the morning glory disk anomaly. This is another unresolved pathogenetic question. It is important to differentiate the morning glory disk anomaly from other "optic nerve colobomas" that include typical uveal colobomas involving the nerve head in which the excavation is greater in the inferior part of the papilla, and the optic nerve head excavation and malformation of the papillo-renal syndrome. Developmental mechanisms leading to the morning glory disk anomaly and the typical optic nerve head coloboma are still under investigation, but the ophthalmoscopic characteristics of these 2 types of malformations are distinct enough to allow clinical differentiation.17Traboulsi E.I. Morning glory disc anomaly or optic disc coloboma?.Arch Ophthalmol. 1994; 112: 153Crossref PubMed Google Scholar, 18Brodsky M.C. Morning glory disc anomaly or optic disc coloboma?.Arch Ophthalmol. 1994; 112: 153Crossref PubMed Scopus (15) Google Scholar The morphology of the optic nerve head in the papillo-renal syndrome due to mutations in PAX219Sanyanusin P. McNoe L.A. Sullivan M.J. Weaver R.G. Eccles M.R. Mutation of PAX2 in two siblings with renal-coloboma syndrome.Hum Mol Genet. 1995; 4: 2183-2184Crossref PubMed Scopus (151) Google Scholar is sometimes confused with a morning glory disk anomaly or a typical coloboma. The importance of the clinical distinction between these malformations lies in the unique genetics and associations of each and the consequent different clinical management plans. Other associations of the morning glory disk anomaly include basal encephalocele, retinal arteriovenous communication, neurofibromatosis type 2, midline or other brain abnormalities such as agenesis of the corpus callosum, and/or craniofacial clefting.11Lee B. Traboulsi E.I. Morning glory disk anomaly revisited.Ophthalm Genet. 2008; 29: 47-52Crossref PubMed Scopus (53) Google Scholar Interestingly, extracranial vessel changes and clefting have been described in the setting of the PHACE (posterior fossa malformations, hemangiomas, arterial abnormalities, cardiac defects, eye abnormalities) syndrome. Numerous cases with a morning glory disk anomaly and facial hemangioma have been described,20Kniestedt C. Landau K. Brodsky M.C. North P. Waner M. Infantile orofacial hemangioma with ipsilateral peripapillary excavation in girls: A variant of the PHACE syndrome.Arch Ophthalmol. 2004; 122: 413-415Crossref PubMed Scopus (18) Google Scholar suggesting a significant overlap with the PHACE neurocutaneous syndrome comprising posterior fossa malformations, facial hemangiomas, arterial, cardiac, and eye abnormalities. It is important to recognize the unique clinical features and serious associations of the morning glory disk anomaly. Vascular imaging studies of the brain such as computed tomography or magnetic resonance angiography are indicated. The identification of potentially lethal abnormalities allows surgical correction in selected patients. Radiological studies will also rule out basal encephaloceles. Traction and rhegmatogenous detachments are amenable to surgical treatment. See accompanying reports on pages 403-407. Morning glory disk anomaly: A computerized analysis of contractile movements with implications for pathogenesisJournal of American Association for Pediatric Ophthalmology and Strabismus {JAAPOS}Vol. 13Issue 4PreviewExcavated optic disk anomalies, such as morning glory disk anomaly, peripapillary staphyloma, and optic disk coloboma, are rare.1 Contractile movement of a given lesion is even rarer. Only 4 patients with morning glory disk anomalies accompanied by contractile movement have been reported.2-5 We offer a computerized analysis of the contraction, observable on a video recording of a patient with this disorder, with an explanation of the possible pathogenesis of the disorder. Full-Text PDF 47 XYY and morning glory syndrome—A unique associationJournal of American Association for Pediatric Ophthalmology and Strabismus {JAAPOS}Vol. 13Issue 4Preview47 XYY syndrome is a sporadic condition in which the human male receives an extra Y chromosome. Few ocular associations have been documented. The authors report the first case of 47 XYY associated with morning glory syndrome, frontonasal meningoencephalocele, and midfacial defects. Full-Text PDF
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