Prithvi Ramtohul1, Michael Engelbert2,3, Ariane Malclès4, Edward Gigon4, Elisabetta Miserocchi5, Giulio Modorati5, Eduardo Cunha de Souza6, Cagri G Besirli7, Christine A Curcio8, K Bailey Freund2,3. 1. Centre Hospitalier Universitaire de l'Hôpital Nord, Marseille, France. 2. Vitreous Retina Macula Consultants of New York, New York, New York. 3. Department of Ophthalmology, NYU Langone School of Medicine, New York, New York. 4. Department of Ophthalmology, Geneva University Hospitals, Geneva, Switzerland. 5. Department of Ophthalmology, San Raffaele Scientific Institute, University Vita-Salute, Milan, Italy. 6. Department of Ophthalmology, Hospital das Clínicas da FMUSP, São Paulo, Brazil. 7. Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan; and. 8. Department of Ophthalmology and Visual Sciences, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
Abstract
PURPOSE: To clarify the histologic basis of bacillary layer detachment (BALAD) through a review of the current literature and an analysis of retinal imaging. METHODS: The literature for previous reports of BALAD were reviewed. An analysis of retinal images was performed to support anatomical conclusions. RESULTS: A total of 164 unique patients with BALAD on optical coherence tomography (OCT) were identified from the published literature. Twenty-two underlying etiologies, all associated with subretinal exudation, were identified. Forty-one different OCT terminologies were found. The defining OCT feature of BALAD was a split at the level of the photoreceptor inner segment myoid creating a distinctive intraretinal cavity. Resolution of BALAD was followed by a rapid restoration of the ellipsoid zone. Histology of age-related macular degeneration eyes suggests that individual photoreceptors can shed inner segments. Furthermore, detachment of the entire layer of inner segments is a common postmortem artifact. It is proposed that BALAD occurs when outwardly directed forces promoting attachment of photoreceptor outer segments to the retinal pigment epithelium exceed the tensile strength of the photoreceptor inner segment myoid. CONCLUSION: This review serves to strengthen the OCT nomenclature "bacillary layer detachment," based on specific reflectance information obtained by OCT and previously published histologic observations.
PURPOSE: To clarify the histologic basis of bacillary layer detachment (BALAD) through a review of the current literature and an analysis of retinal imaging. METHODS: The literature for previous reports of BALAD were reviewed. An analysis of retinal images was performed to support anatomical conclusions. RESULTS: A total of 164 unique patients with BALAD on optical coherence tomography (OCT) were identified from the published literature. Twenty-two underlying etiologies, all associated with subretinal exudation, were identified. Forty-one different OCT terminologies were found. The defining OCT feature of BALAD was a split at the level of the photoreceptor inner segment myoid creating a distinctive intraretinal cavity. Resolution of BALAD was followed by a rapid restoration of the ellipsoid zone. Histology of age-related macular degeneration eyes suggests that individual photoreceptors can shed inner segments. Furthermore, detachment of the entire layer of inner segments is a common postmortem artifact. It is proposed that BALAD occurs when outwardly directed forces promoting attachment of photoreceptor outer segments to the retinal pigment epithelium exceed the tensile strength of the photoreceptor inner segment myoid. CONCLUSION: This review serves to strengthen the OCT nomenclature "bacillary layer detachment," based on specific reflectance information obtained by OCT and previously published histologic observations.
Authors: Raphaela M Fuganti; Antonio M Casella; Luiz Roisman; Claudio Zett; Maurício Maia; Michel E Farah; Luiz H Lima Journal: Am J Ophthalmol Case Rep Date: 2022-09-07