Takusagawa HL, Hoguet A, Junk AK, Nouri-Mahdavi K, Radhakrishnan S, Chen TC.
Swept-Source OCT for Evaluating the Lamina Cribrosa: A Report by the American Academy of Ophthalmology. Ophthalmology 2019;126(9):1315-1323.
AbstractPURPOSE: To review the published literature on the use of swept-source (SS) OCT for evaluating the lamina cribrosa in glaucoma. METHODS: A PubMed and Cochrane Library literature search initially conducted on March 3, 2017, and updated on June 26, 2018, yielded a total of 64 articles. Articles that were reviews or that were not published in English were excluded, and 29 were found to fit the inclusion criteria. The panel methodologist then assigned a level of evidence rating to each study. Fifteen studies were rated level III, 14 studies were rated level II, and no studies were rated level I. RESULTS: Different aspects of the lamina cribrosa were studied using SS-OCT, including the anterior lamina cribrosa curvature, anterior lamina cribrosa depth, anterior lamina cribrosa insertions, laminar thickness, focal lamina cribrosa defects (FLCDs), and lamina cribrosa microarchitecture. In general, imaging of the anterior lamina can be achieved reliably, although shadowing from blood vessels at the neuroretinal rim remains an issue. Imaging of the posterior lamina can be achieved with varying levels of success. In glaucoma, there is posterior migration of the anterior lamina cribrosa insertions as well as increased thinning and posterior curvature of the lamina cribrosa. Focal lamina cribrosa defects appear more commonly in glaucoma, and this may hint at the pathogenesis of axonal damage. In addition, there may be remodeling of the microarchitecture of the lamina, resulting in more variable laminar pores. There are limited studies comparing SS-OCT with spectral-domain (SD) OCT with regard to imaging of the lamina, but the difference in image quality between enhanced depth imaging (EDI) with SD-OCT and SS-OCT seems minimal. CONCLUSIONS: Imaging of the lamina cribrosa using SS-OCT has demonstrated that the lamina cribrosa is likely biomechanically active and that significant changes occur in glaucoma. The diagnostic utility of SS-OCT for lamina cribrosa imaging is promising, but standardized nomenclature, automated measurements, and longitudinal studies with larger and more diverse sample sizes are needed.
Tieger MG, Jakobiec FA, Ma L, Wolkow N.
Small Benign Storiform Fibrous Tumor (Fibrous Histiocytoma) of the Conjunctival Substantia Propria in a Child: Review and Clarification of Biologic Behavior. Ophthalmic Plast Reconstr Surg 2019;35(5):495-502.
AbstractPURPOSE: A case of a small benign storiform fibrous tumor of the conjunctival substantia propria is described to clarify the category of fibrous histiocytoma. In addition, a comparison of the various spindle cell tumors of the conjunctival substantia propria is explored. METHODS: The patient underwent a complete tumor excision, and the specimen was analyzed by histopathologic and immunohistochemical investigations. RESULTS: A cellular mass, composed solely of spindle cells in a storiform pattern without a component of histiocytic cells, was found beneath an undisturbed nonkeratinizing squamous epithelium and was separated from the epithelium by a grenz zone of uninvolved collagen. The lesion was sharply demarcated but not encapsulated. The Masson trichrome stain revealed scant deposition of intercellular collagen. The reticulin stain displayed numerous and delicate wiry fibers between the tumor cells and encircling capillaries. The Alcian blue stain demonstrated faint positivity in the interstitium. Immunohistochemistry revealed positivity for vimentin, factor XIIIa, smooth muscle actin, CD10, and CD45. Negative stains were obtained for CD34, CD56, S100, desmin, and Ki67. CONCLUSIONS: The broad term of fibrous histiocytoma should be reserved for deep fibroblastic spindle cell tumors (e.g., those of the orbit) that display an aggressive behavior. More benign superficial spindle cell tumors of the dermis are now preferentially characterized as dermatofibromas. It is suggested that equally benign epibulbar tumors should no longer be designated as fibrous histiocytomas but rather as benign storiform fibrous tumors. Tumors completely composed of polygonal histiocytoid (epithelioid) cells that are CD34+ should be excluded from the benign storiform fibrous tumor category. Positive smooth muscle actin and factor XIIIa staining in conjunction with negative staining for CD34 and desmin in the current spindled tumor cells are findings consistent with those of cutaneous dermatofibromas. Both the epibulbar and dermal spindle cell lesions have displayed an indolent and nonaggressive behavior. Microscopically they contain a high proportion of dendrocytic stellate cells that are either factor XIIIa+ or XIIIa-. Given the anatomic differences between the dermis and conjunctiva, the term dermatofibroma is inappropriate for the current tumor; instead the term benign storiform fibrous tumor has been proposed for superficial tumors of the conjunctiva.