The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform

Jonas A. Castelijns - One of the best experts on this subject based on the ideXlab platform.

  • guidelines for imaging retinoblastoma imaging principles and mri standardization
    Pediatric Radiology, 2012
    Co-Authors: Pim De Graaf, Sophia Goricke, Firazia Rodjan, Paolo Galluzzi, Philippe Maeder, Jonas A. Castelijns, Henry Brisse
    Abstract:

    Retinoblastoma is the most common intraocular tumor in children. The diagnosis is usually established by the ophthalmologist on the basis of fundoscopy and US. Together with US, high-resolution MRI has emerged as an important imaging modality for pretreatment assessment, i.e. for diagnostic confirmation, detection of local tumor extent, detection of associated developmental malformation of the brain and detection of associated intracranial primitive neuroectodermal tumor (trilateral retinoblastoma). Minimum requirements for pretreatment diagnostic evaluation of retinoblastoma or mimicking lesions are presented, based on consensus among members of the European Retinoblastoma Imaging Collaboration (ERIC). The most appropriate techniques for imaging in a child with leukocoria are reviewed. CT is no longer recommended. Implementation of a standardized MRI protocol for retinoblastoma in clinical practice may benefit children worldwide, especially those with hereditary retinoblastoma, since a decreased use of CT reduces the exposure to ionizing radiation.

  • retinal dysplasia mimicking intraocular tumor mr imaging findings with histopathologic correlation
    American Journal of Neuroradiology, 2007
    Co-Authors: Paul Van Der Valk, A C Moll, Saskia M Imhof, A Schoutenvan Y N Meeteren, Jonas A. Castelijns
    Abstract:

    We report a 6-month-old boy who presented with unilateral leukocoria, retinal detachment, and a retrolental mass in a microphthalmic eye based on retinal dysplasia with concurrent optic nerve aplasia. Dysplastic retinal tissue, a rare congenital defect, may create a clinical and radiologic picture of an intraocular mass closely resembling tumor tissue. MR imaging findings with histopathologic correlation are presented to facilitate discrimination of the more common causes of leukocoria.

Ronald L. Green - One of the best experts on this subject based on the ideXlab platform.

  • Echographic Characteristics of Ocular Toxocariasis
    Ophthalmology, 1991
    Co-Authors: W. Lee Wan, Miriam R. Cano, Keith J. Pince, Ronald L. Green
    Abstract:

    Ocular toxocariasis most commonly presents as one of three distinct clinical syndromes: endophthalmitis, localized posterior granuloma, or peripheral granuloma. Using standardized echography, the authors studied 11 toxocariasis patients presenting with one of these syndromes. Common echographic findings were noted in ten of these patients, and included: (1) a solid, high-reflective peripheral mass, (2) a vitreous band or membranes extending between the posterior pole and the mass, and (3) a traction retinal detachment or fold from the posterior pole to the mass. These findings were present in patients presenting with leukocoria or endophthalmitis, as well as in patients in whom the peripheral nematode lesion could be visualized clinically. In combination with the history, clinical examination, and enzyme-linked immunosorbent assay (ELISA), standardized echography may be useful in establishing the diagnosis of ocular toxocariasis in cases of leukocoria in which nematode endophthalmitis is suspected.

Thaddeus P. Dryja - One of the best experts on this subject based on the ideXlab platform.

Ramon L Font - One of the best experts on this subject based on the ideXlab platform.

  • melanogenic neuroectodermal tumor of the retina primary malignant melanoma of the retina
    Archives of Ophthalmology, 1997
    Co-Authors: Suzanne K Freitag, Ralph C. Eagle, Jerry A. Shields, Jay S Duker, Ramon L Font
    Abstract:

    A 35-month-old girl with leukocoria was clinically diagnosed with unilateral sporadic retinoblastoma. Macroscopic examination of her enucleated eye disclosed a white retinal tumor that appeared to be a retinoblastoma. Histopathologic examination, however, revealed that the tumor was composed of poorly differentiated neuroblastic cells, larger spindle-shaped cells, and anaplastic epithelioid cells, which is inconsistent with retinoblastoma. Immunohistochemical testing disclosed that the tumor cells were immunoreactive for melanoma-specific antigen HMB-45, while electron microscopy showed premelanosomes in the tumor cells, both of which are consistent with melanogenesis. To our knowledge, such an ocular tumor has not been reported previously.

Shizuo Mukai - One of the best experts on this subject based on the ideXlab platform.

  • colorimetric and longitudinal analysis of leukocoria in recreational photographs of children with retinoblastoma
    PLOS ONE, 2013
    Co-Authors: Alireza Abdolvahabi, Brandon W Taylor, Rebecca L Holden, Elizabeth V Shaw, Alex Kentsis, Carlos Rodriguezgalindo, Shizuo Mukai, Bryan F Shaw
    Abstract:

    Retinoblastoma is the most common primary intraocular tumor in children. The first sign that is often reported by parents is the appearance of recurrent leukocoria (i.e., “white eye”) in recreational photographs. A quantitative definition or scale of leukocoria – as it appears during recreational photography – has not been established, and the amount of clinical information contained in a leukocoric image (collected by a parent) remains unknown. Moreover, the hypothesis that photographic leukocoria can be a sign of early stage retinoblastoma has not been tested for even a single patient. This study used commercially available software (Adobe Photoshop®) and standard color space conversion algorithms (operable in Microsoft Excel®) to quantify leukocoria in actual “baby pictures” of 9 children with retinoblastoma (that were collected by parents during recreational activities i.e., in nonclinical settings). One particular patient with bilateral retinoblastoma (“Patient Zero”) was photographed >7, 000 times by his parents (who are authors of this study) over three years: from birth, through diagnosis, treatment, and remission. This large set of photographs allowed us to determine the longitudinal and lateral frequency of leukocoria throughout the patient's life. This study establishes: (i) that leukocoria can emerge at a low frequency in early-stage retinoblastoma and increase in frequency during disease progression, but decrease upon disease regression, (ii) that Hue, Saturation and Value (i.e., HSV color space) are suitable metrics for quantifying the intensity of retinoblastoma-linked leukocoria; (iii) that different sets of intraocular retinoblastoma tumors can produce distinct leukocoric reflections; and (iv) the Saturation-Value plane of HSV color space represents a convenient scale for quantifying and classifying pupillary reflections as they appear during recreational photography.

  • colorimetric and longitudinal analysis of leukocoria in recreational photographs of children with retinoblastoma
    PLOS ONE, 2013
    Co-Authors: Alireza Abdolvahabi, Brandon W Taylor, Rebecca L Holden, Elizabeth V Shaw, Alex Kentsis, Carlos Rodriguezgalindo, Shizuo Mukai, Bryan F Shaw
    Abstract:

    Retinoblastoma is the most common primary intraocular tumor in children. The first sign that is often reported by parents is the appearance of recurrent leukocoria (i.e., “white eye”) in recreational photographs. A quantitative definition or scale of leukocoria – as it appears during recreational photography – has not been established, and the amount of clinical information contained in a leukocoric image (collected by a parent) remains unknown. Moreover, the hypothesis that photographic leukocoria can be a sign of early stage retinoblastoma has not been tested for even a single patient. This study used commercially available software (Adobe Photoshop®) and standard color space conversion algorithms (operable in Microsoft Excel®) to quantify leukocoria in actual “baby pictures” of 9 children with retinoblastoma (that were collected by parents during recreational activities i.e., in nonclinical settings). One particular patient with bilateral retinoblastoma (“Patient Zero”) was photographed >7, 000 times by his parents (who are authors of this study) over three years: from birth, through diagnosis, treatment, and remission. This large set of photographs allowed us to determine the longitudinal and lateral frequency of leukocoria throughout the patient's life. This study establishes: (i) that leukocoria can emerge at a low frequency in early-stage retinoblastoma and increase in frequency during disease progression, but decrease upon disease regression, (ii) that Hue, Saturation and Value (i.e., HSV color space) are suitable metrics for quantifying the intensity of retinoblastoma-linked leukocoria; (iii) that different sets of intraocular retinoblastoma tumors can produce distinct leukocoric reflections; and (iv) the Saturation-Value plane of HSV color space represents a convenient scale for quantifying and classifying pupillary reflections as they appear during recreational photography.

  • Case records of the Massachusetts General Hospital. Case 5-2006. An 11-year-old girl with loss of vision in the right eye.
    The New England journal of medicine, 2006
    Co-Authors: David S. Walton, Shizuo Mukai, Eric F. Grabowski, John E. Munzenrider, Thaddeus P. Dryja
    Abstract:

    An 11-year-old girl noticed a sudden loss of vision in her right eye. An examination disclosed Leukokoria; she was sent to the emergency department. A test for visual acuity revealed only light perception in the right eye. Further examination and an ultrasonographic study disclosed a detached retina.