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J A Shields

Publications and source records attributed to J A Shields.

At least 235 records · Page 13Linked to original sources
PubMed1995

Localized transscleral staphylococcal abscess simulating a neoplasm.

A 47-year-old woman with a history of breast cancer developed a focal epibulbar mass in the right eye. The initial diagnosis was nodular episcleritis, but the lesion failed to respond to local and systemic corticosteroids. The rule out an epibulbar metastatic carcinoma an excisional biopsy was performed, which demonstrate a localized staphylococcal abscess that had locally eroded the sclera and exposed the underlying uveal tract. Covering the defect with a scleral patch graft and promptly instituting oral amoxicillin/clavulanic acid and topical cefazolin treatment resulted in an uncomplicated recovery. Infectious scleral abscess in an uncommon entity and the differential diagnosis includes nodular episcleritis and epibulbar metastatic tumor.

Abscess↗
PubMed1995

Endogenous endophthalmitis simulating retinoblastoma. The 1993 David and Mary Seslen Endowment Lecture.

BACKGROUND: Among conditions that can simulate retinoblastoma, endogenous endophthalmitis is quite rare. METHODS: Case records of six children with unusual forms of endogenous endophthalmitis, all of whom were referred to the authors because retinoblastoma was a strong diagnostic consideration, were reviewed. The clinical features that may help differentiate atypical endophthalmitis from retinoblastoma were investigated. RESULTS: The final diagnosis in these cases included idiopathic subretinal abscess, streptococcal endophthalmitis, idiopathic retinovitreal abscess, cytomegalovirus endophthalmitis, Candida endophthalmitis, and meningococcal endophthalmitis. All of the affected children presented primarily with ocular findings without serious systemic infection. Although these conditions closely simulated retinoblastoma, they were more likely to have signs of concurrent or prior inflammation. CONCLUSION: Differentiation between infectious conditions and retinoblastoma can sometimes be difficult, but clues as to the diagnosis can be obtained from careful clinical examination.

Abscess↗
PubMed1995

Iris melanoma in ocular melanocytosis.

A pigmented, circumscribed iris lesion thought to be a nevus was noted in the right eye of a 64-year-old man with congenital ocular melanocytosis. Although the patient had excess episcleral and choroidal pigmentation, the iris in the affected eye was blue. Two years later, growth was documented, suggesting that the lesion was malignant. The tumor was resected by a sector iridectomy and studied by light microscopy. Histopathologically, the tumor was shown to be a malignant melanoma of the mixed-cell type. No evidence of congenital melanocytosis was found in the adjoining normal iris. This is a well-documented case of a malignant melanoma of the iris arising in a blue, uninvolved iris in a patient with sectoral congenital ocular melanocytosis. Although this specific association has not been previously reported, we believe that any pigmented uveal tumor occurring in the setting of congenital ocular melanocytosis should be observed closely for growth that can signal malignant transformation.

Choroid Neoplasms↗
PubMed1995

Risk factors for growth and metastasis of small choroidal melanocytic lesions.

PURPOSE: To investigate the clinical features that predict growth and metastasis of an unselected group of small melanocytic choroidal tumors. METHODS: A retrospective review was performed on 1329 patients with small melanocytic choroidal tumors measuring 3 mm in thickness or less. Clinical parameters of the patient and tumor were extracted and analyzed for their relationship to eventual tumor growth and metastasis using a Cox proportional hazards regression model. RESULTS: Tumor growth was documented in 18% of patients. The factors predictive of tumor growth (multivariate analysis) included greater tumor thickness, posterior tumor margin touching optic disc, symptoms of flashes, floaters, and blurred vision, orange pigment on the tumor surface, and the presence of subretinal fluid. The relative risk (rr) was greatest for initial tumor thickness > 2.0 mm (rr 5.2) and posterior margin touching the optic disc (rr 2.6). After adjusting for significant tumor variables, the effect of interventional tumor treatment showed a decreasing risk for tumor growth as compared to continued observation without treatment. Of 1329 patients, 35 (3%) developed metastases. The factors predictive of metastases (multivariate analysis) included: posterior tumor margin touching the optic disc, documented growth, and greater tumor thickness. The relative risk for metastases was greatest for tumor thickness 1.1-3.0 mm (rr 8.8) and growth (rr 3.2). CONCLUSION: Of small choroidal melanocytic tumors measuring 3 mm or less in thickness at the time of initial examination, 18% demonstrate growth and 3% metastasize during the period of followup. Based on this analysis, the clinical features of these tumors can be used to estimate the risk for tumor growth and metastases and assist the clinician with patient management.

Adolescent↗
PubMed1995

Risk factors for growth and metastasis of small choroidal melanocytic lesions.

BACKGROUND: The management of small melanocytic choroidal tumors is controversial. An important reason for this controversy is that the natural course and metastatic potential of these lesions are not defined clearly. Prior studies that have attempted to elucidate the natural course of these lesions have focused on selected small groups of patients with presumed small choroidal melanomas. There are no large studies investigating the growth potential and metastatic potential for the spectrum of small melanocytic choroidal tumors when considered as an unselected whole group. In addition, the clinical features of these tumors predictive of metastases have not yet been identified. METHODS: A retrospective review was performed on 1329 patients with small melanocytic choroidal tumors measuring 3 mm or less in thickness. Clinical parameters of the patient and tumor were obtained and analyzed for their relation to eventual tumor growth and metastasis using a Cox proportional hazards regression model. RESULTS: Tumor growth was documented in 18% of patients. The factors predictive of tumor growth (multivariate analysis) included greater tumor thickness (P = 0.0001), posterior tumor margin touching optic disc (P = 0.0001), symptoms of flashes, floaters (P = 0.002), and blurred vision (P = 0.003) relative to no symptoms, orange pigment on the tumor surface (P = 0.004), and the presence of subretinal fluid (P = 0.05). The relative risk (RR) was greatest for initial tumor thickness 2.1 to 3.0 mm (RR = 5.2) and tumor thickness 1.1 to 2.0 mm (RR = 4.3) relative to tumors 1 mm or less in thickness, as well as posterior margin touching the optic disc (RR = 2.6). After adjusting for significant tumor variables, the effect of interventional tumor treatment showed a decreasing risk for tumor growth compared with continued observation without treatment. Of 1329 patients, metastases developed in 35 (3%). The factors predictive of metastases (multivariate analysis) included posterior tumor margin touching the optic disc (P = 0.003), documented growth (P = 0.003), and greater tumor thickness (P = 0.004). The relative risk for metastases was greatest for tumor thickness 1.1 to 3.0 mm (RR = 8.8) and growth (RR = 3.2). CONCLUSION: Of small choroidal melanocytic tumors measuring 3 mm or less in thickness at the time of initial examination, 18% demonstrated growth and 3% metastasized during the period of follow-up. Based on this analysis, the clinical features of these tumors can be used to estimate the risk for tumor growth and metastases and assist the clinician with patient management.

Adolescent↗
PubMed1995

Uveal melanomas in black patients: a case series and comparative review.

Uveal melanomas are rare in black patients. Of a total of 2586 patients with the diagnosis of posterior uveal melanoma who were managed in the Oncology Service at Wills Eye Hospital from 1974 to 1987, 10 patients (0.39%) were black. Data on patient age (mean: 53.9 years), sex (male-to-female ratio: 7:3), and relative frequency of disease between black (0.39% of total cases) and white patients were similar to that of previous reports. The distinguishing characteristics (incidence, risk factors, complications, and prognostic indicators) of uveal melanoma in black versus white patients also were reviewed.

Adult↗
PubMed1994

Rarity of somatic and germline mutations of the cyclin-dependent kinase 4 inhibitor gene, CDK4I, in melanoma.

Evidence from cytogenetics, multipoint linkage analyses of familial melanoma, and loss of heterozygosity studies of familial and sporadic melanomas support localization of a melanoma susceptibility or tumor suppressor gene at chromosomal region 9p21-23. Recently, the inhibitor of cyclin-dependent kinase 4 (CDK4I; also known as p16INK4, multiple tumor suppressor 1, or CDKN2 gene) has been mapped to 9p21 and shown to be mutated or deleted in a large fraction of cell lines derived from many tumor types, including melanoma, suggesting that this gene could be a melanoma suppressor gene. In order to test for somatic mutations in the CDK4I gene in tumors, DNAs from 30 surgically resected melanomas of both cutaneous and uveal origins were sequenced. No mutations were detected in the coding region of the CDK4I gene, while mutations or deletions were detected in 60% (9 of 15) of the cultured melanoma cell line DNAs. Among presumptive familial cases, nine of which were members of families with one or two other documented melanoma cases, no germline mutations were detected by sequence analysis. A deletion in the second exon of the CDK4I gene was found in one germline allele of a familial melanoma patient from a family with eight affected first degree relatives. These results not only support the suggestion that the CDK4I gene is a familial malignant melanoma gene, they also suggest the presence of another suppressor gene locus within 9p21 which is the target of loss of heterozygosity in sporadic melanomas.

Base Sequence↗
PubMed1994

Optic nerve invasion of retinoblastoma. Metastatic potential and clinical risk factors.

BACKGROUND: Optic nerve invasion is one of the predictors for retinoblastoma metastases. This study was designed to investigate the risk of optic nerve invasion and clinical features that may identify those children with optic nerve invasion. METHODS: We reviewed the charts of 289 children with retinoblastoma treated initially with enucleation. Logistic regression analysis was performed to assess the risk for metastases from varying degrees of optic nerve invasion and to assess the clinical and histopathologic predictors of optic nerve invasion. RESULTS: There were 84 eyes (29%) with optic nerve invasion. The invasion was prelamina cribrosa in 44 cases (15%), up to but not posterior to the lamina cribrosa in 21 cases (7%), posterior to the lamina cribrosa but not to the cut end of the optic nerve in 17 cases (6%), and to the site of optic nerve transection in 2 cases (1%). Patients with optic nerve invasion were more likely to develop metastasis (P = 0.0016), particularly those with invasion to the postlaminar and cut section of the optic nerve (P = 0.0001). Development of metastasis was not statistically associated with laminar or prelaminar involvement. If those patients with choroidal invasion simultaneous with optic nerve invasion were excluded from evaluation, the presence of optic nerve invasion alone was not significant for development of metastasis. The clinical factors found to be predictive for optic nerve invasion from a univariate analysis included exophytic growth pattern (P = 0.011), elevated intraocular pressure (> 22 mm Hg) (P = 0.02), and tumor thickness greater than or equal to 15 mm (P = 0.03). The histopathologic factor significantly associated with optic nerve invasion (univariate analysis) was simultaneous choroidal invasion (P = 0.001). A trend toward an association with optic nerve invasion was found with vitreous hemorrhage (P = 0.06), iris neovascularization (P = 0.10), and poorly differentiated retinoblastoma (P = 0.07). A multivariate analysis showed the most significant clinical factors to be exophytic growth pattern (P = 0.002), tumor thickness greater than or equal to 15 mm (P = 0.01), and vitreous hemorrhage (P = 0.05). CONCLUSIONS: Optic nerve invasion of retinoblastoma beyond the lamina cribrosa is associated with a greater metastatic risk. Large exophytic retinoblastoma with secondary glaucoma is at highest risk for optic nerve invasion.

Child, Preschool↗
PubMed1994

Use of the hydroxyapatite ocular implant in the pediatric population.

OBJECTIVES: There is always a hesitancy to use an ocular implant after enucleation in children, especially in cases of eyes enucleated for retinoblastoma. DESIGN AND SETTING: In this prospective study, we report our experience of 60 consecutive cases in which we used the hydroxyapatite ocular implant after enucleation in children younger than age 10 years. RESULTS: The mean age at the time of enucleation and hydroxyapatite placement was 27 months (range, 1 to 108 months). The histopathologic diagnoses after enucleation included retinoblastoma in 51 patients, endophthalmitis in two patients, persistent hyperplastic primary vitreous in two patients, neovascular glaucoma resulting from Coats' disease in one patient, uveal melanoma in two patients, undifferentiated intraocular neoplasm in one patient, and blind painful traumatized eye in one patient. After a mean follow-up of 19 months (range, 6 to 36 months), two cases of conjunctival erosion and five cases of conjunctival thinning were recorded. These problems were associated with a flat posterior prosthesis vault in all seven cases. There were no cases of orbital cellulitis, implant extrusion, or implant migration. All children showed good small-degree prosthesis motility despite the lack of peg placement. Only one older child underwent drilling and peg placement and she had excellent small- and large-degree prosthesis motility. We generally postpone the drilling and peg placement stage and tedious prosthesis revision in children until they are able to fully cooperate with the ocularist. CONCLUSIONS: The hydroxyapatite ocular implant is well tolerated and provides good prosthesis motility in children with few complications. It is critical for the ocularist to fit the prosthesis comfortably with a high posterior vault.

Child↗
PubMed1994

Primitive neuroectodermal tumor of the orbit.

A 10-year-old girl developed a lump in the lateral aspect of the right eyebrow over a 3-week period. Computed tomography and magnetic resonance imaging revealed a soft-tissue mass in the superolateral aspect of the right orbit associated with zygo-maticofrontal bone erosion and hyperostosis. An incisional biopsy specimen was studied using light microscopy, immunohistochemical staining, and electron microscopy, resulting in a diagnosis of peripheral primitive neuroectodermal tumor. The results of an extensive evaluation for systemic involvement were negative. The patient was subsequently treated with chemotherapy and radiation therapy. Primary primitive neuroectodermal tumor of the orbit is rare. The differential diagnosis and the diagnostic features of this entity are discussed herein.

Child↗
PubMed1994

The role of fat-suppression technique and gadopentetate dimeglumine in magnetic resonance imaging evaluation of intraocular tumors and simulating lesions.

OBJECTIVE: Recent studies have shown that contrast (gadopentetate dimeglumine)-enhanced magnetic resonance imaging is useful in evaluating intraocular tumors and differentiating uveal melanoma from other simulating lesions. The purpose of this study was to study prospectively the role of fat-suppression technique and gadopentetate dimeglumine-enhanced magnetic resonance imaging in the evaluation of intraocular neoplasia. PATIENTS: Forty-three uveal melanomas and 20 other simulating intraocular lesions from 63 patients were prospectively evaluated on non-contrast-enhanced and post-contrast-enhanced T1-weighted images with and without fat-suppression technique and on T2-weighted images. RESULTS: Forty-one uveal melanomas (95%) were detected with standard pulse sequences and showed the characteristic hyperintense signal on non-contrast-enhanced T1-weighted images and hypointense signal with respect to the vitreous on T2-weighted images. All 33 uveal melanomas evaluated on non-contrast-enhanced T1-weighted images with fat-suppression technique were detected on non-contrast-enhanced images with fat-suppression technique. The intensity of the signal was statistically associated with the degree of pigmentation of the tumor on T1-weighted images with fat-suppression technique (P = .03). On post-contrast-enhanced T1-weighted images with or without fat-suppression technique, the 43 uveal melanomas showed enhancement. The degree of tumor enhancement was not statistically related to the degree of tumor pigmentation or the location of the tumor. Among the other simulating intraocular lesions, choroidal metastasis, retinoblastoma, choroidal leiomyoma, and medulloepithelioma demonstrated the same features on magnetic resonance imaging studies as uveal melanoma demonstrated on non-contrast-enhanced and post-contrast-enhanced T1-weighted images with or without fat-suppression technique. In our series, choroidal hemangioma, choroidal osteoma, posterior scleritis, retinal hemangioma, and Coats' disease can be differentiated from other amelanotic intraocular tumors by their characteristics on magnetic resonance imaging studies. CONCLUSIONS: We concluded that pre-and post-contrast-enhanced T1-weighted images with fat-suppression technique are most helpful in detecting small intraocular tumors with a thickness of more than 1.8 mm and in evaluating intraocular neoplasms and simulating lesions, particularly when T2-weighted images are not available. Moreover, in juxtapapillary choroidal or retinal tumor, fat-suppression technique may help in the detection of possible optic nerve or orbital extension by improving the conspicuousness of the tumor.

Adipose Tissue↗
PubMed1994

Observations on seven cases of intraocular leiomyoma. The 1993 Byron Demorest Lecture.

A review of seven cases of intraocular leiomyoma personally managed by the authors disclosed clinical and histopathologic characteristics that serve to differentiate this uncommon tumor from uveal melanoma. Leiomyoma generally occurs in younger patients and has a definite predilection for females. It tends to affect the ciliary body and peripheral choroid rather than the posterior choroid. In contrast to melanoma, which is located in the uveal stroma, leiomyoma usually is located in the supraciliary or suprachoroidal space. During transillumination, leiomyoma usually transmits light readily, whereas most melanomas cast a shadow. If intraocular leiomyoma is suspected clinically, the best management seems to be removal by a modified lamellar sclerouvectomy. In contrast to melanoma, leiomyoma shows positive immunoreactivity for muscle markers and negative immunoreactivity for melanoma-specific antigen and neural markers.

Adult↗
PubMed1994

Adenocarcinoma of retinal pigment epithelium arising from a juxtapapillary histoplasmosis scar.

A 66-year-old woman underwent a transocular fine-needle aspiration biopsy for an enlarging mass arising from a juxtapapillary histoplasmosis scar in the left eye. The cytologic study revealed pigmented malignant cells, suggesting that the lesion was either a malignant choroidal melanoma or an adenocarcinoma of the retinal pigment epithelium. The eye was enucleated and histopathologic studies revealed findings suggestive of an adenocarcinoma of the retinal pigment epithelium. Immunohistochemical stains were positive for cytokeratin and were negative for melanoma-specific antigen, supporting an epithelial origin of the neoplasm. It is possible that the tumor developed as a neoplastic transformation of a reactive proliferation of the retinal pigment epithelium in a histoplasmosis scar. The possible association between a chorioretinal scar and the development of a tumor of the pigment epithelium is discussed herein.

Adenocarcinoma↗
PubMed1994

Cytogenetic findings in primary uveal melanoma.

We analyzed cytogenetic abnormalities in 10 cases of primary uveal melanoma. Clonal chromosomal abnormalities were present in nine cases. Chromosome 6 was most commonly affected (seven cases) and included gain of material from 6 and/or loss of material from 6q. Trisomy of chromosome 8 or gain in material from 8q, mostly in the form of an i(8q) resulting in three to five copies of the 8q segment was seen in six cases. Monosomy of chromosome 3 and rearrangements of chromosome 9 were less frequent and were altered in three cases each. Clinical, histopathologic, and cytogenetic abnormalities are correlated.

Adult↗
PubMed1994

Current management of retinoblastoma.

OBJECTIVE: The recommended management of retinoblastoma based on personal experience with the assessment and treatment of more than 450 children with this intraocular malignant lesion is presented. RECOMMENDATIONS: Although retinoblastoma is usually managed by enucleation, the treatment of each case must be individualized; in an increasing number of children, the techniques of irradiation, photocoagulation, or cryotherapy are being used. In some patients, a combination of these techniques is necessary. Chemotherapy is often used to prevent distant metastatic involvement, although its effectiveness as a prophylactic treatment has not been clearly established. Because metastatic retinoblastoma is often fatal, intense chemotherapy is recommended in this setting. CONCLUSION: The prognosis for vision and life in patients with retinoblastoma has improved considerably during the past century, primarily because of earlier recognition of the tumor and use of modern therapeutic methods. All children of parents with a family history of retinoblastoma should be examined by a qualified ophthalmologist immediately after birth in order to detect and treat this condition as early as possible.

Child↗
PubMed1994

Melanotic schwannoma of the choroid. Immunohistochemistry and electron microscopic observations.

PURPOSE: The purpose of this article is to describe what is probably the first reported case of a melanotic schwannoma of the choroid and to discuss the clinical and histopathologic features that serve to differentiate this rare intraocular tumor from a malignant melanoma of the choroid. PATIENT AND METHODS: A 21-year-old woman underwent enucleation of the right eye for a slowly enlarging pigmented choroidal mass that was associated with ipsilateral blindness. The tumor was studied by light microscopy, immunohistochemistry, and electron microscopy. FINDINGS: The tumor was composed of fascicles and whorls of pigmented and nonpigmented plump spindle cells that had light microscopic features of a schwannoma. The tumor cells showed immunoreactivity to S-100 protein and HMB-45. Electron microscopy showed cytoplasmic processes surrounded by a continuous basement membrane and abundant extracellular collagen. The pigmented spindle-shaped cells contained melanosomes in different stages of melanogenesis. The findings were compatible with a melanotic schwannoma. CONCLUSION: Melanotic schwannoma has been reported in soft tissues, peripheral nerves, and in the orbit. To the authors' knowledge, this is the first report of a melanotic schwannoma of the choroid. This extremely rare pigmented choroidal tumor may be very difficult to differentiate clinically from choroidal melanoma.

Adult↗