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Biomedical subjects

J A Shields

Publications and source records attributed to J A Shields.

At least 343 records · Page 19Linked to original sources
PubMed1991

Massive orbital extension of posterior uveal melanomas.

Among 2,135 consecutive patients with posterior uveal melanoma who were evaluated clinically in the Ocular Oncology Service of Wills Eye Hospital between February 1974 and December 1986, 123 (5.8%) were found to have some degree of extrascleral extension of the tumor. Ten of the 2,135 patients (0.5%) had massive orbital extension we defined as extrascleral tumor having an estimated volume exceeding 1,000 mm3. Three of these patients were characterized by orbital recurrence sometime after enucleation, whereas seven had massive orbital extension as the initial manifestation of the neoplasm with no prior history of enucleation. These cases of advanced orbital extension are presented in detail with emphasis on clinical features, diagnostic problems, pathologic findings, and follow-up observation. Based on our observations, suggestions are made regarding the diagnosis and management of advanced orbital extension of posterior uveal melanoma.

Adult↗
PubMed1991

Magnetic resonance imaging in choroidal osteoma.

High resolution magnetic resonance imaging (MRI) with surface coil and contrast material was used to demonstrate the presence of bone in choroidal osteoma. Contrary to initial impressions, choroidal osteoma does not show typical negative image of the bone in MRI scans. The ossifying tumor of the choroid appears as a bright (hyperintense) signal on T1-weighted images and as an area of relative low intensity on T2-weighted images. On contrast T1-weighted scans, the tumor showed gadolinium-DPTA (Gd-DPTA) enhancement. These MRI findings are discussed in relation with histopathologic features of choroidal osteoma and the presence of fat marrow in the intertrabecular spaces of the bone at the level of the choroid.

Adult↗
PubMed1991

Orbital exenteration with eyelid sparing: indications, technique, and results.

Of 22 orbital exenterations performed from January 1980 to December 1989, 16 were performed by an eyelid-sparing technique, and six were allowed to heal by spontaneous granulation. Reviewing these procedures, we conclude that the eyelid-sparing method is indicated mainly for advanced primary orbital malignancies and for certain secondary orbital malignancies such as orbital extension of uveal melanoma, conjunctival melanoma, and conjunctival squamous cell carcinoma. It is not usually applicable to orbital invasion of malignant eyelid tumors such as basal cell carcinoma and sebaceous gland carcinoma. Advantages of the eyelid-sparing method are more rapid healing and earlier fitting of a prosthesis.

Aged↗
PubMed1991

Malignant tumors of the eye in geriatric patients.

The ocular tissues can be the site of a number of malignant tumors in adults and geriatric patients. In addition to posing a threat to the patient's life, these tumors can cause severe visual loss or blindness. Therefore, the primary care clinician should be capable of prompt diagnosis of the various malignant ocular tumors and be prepared to refer the patient for appropriate management. This article provides a photographic guide to the most common primary and secondary malignancies that can affect the eyelid, conjunctiva, intraocular structures, and orbit in the geriatric patient.

Aged↗
PubMed1991

Differential diagnosis of retinoblastoma.

Retinoblastoma is a malignant intraocular tumor of childhood that requires accurate diagnosis and prompt treatment. It is well known that several other ocular conditions of childhood can clinically simulate retinoblastoma. Knowledge of the clinical features that serve to differentiate retinoblastoma from simulating lesions may assist the clinician in arriving at the correct diagnosis and preventing misdirected therapy. This review provides a simple classification of those pseudoretinoblastomas and reviews the recent literature on this subject. It emphasizes the clinical features that help differentiate pseudoretinoblastomas from true retinoblastoma.

Diagnosis, Differential↗
PubMed1991

Band keratopathy secondary to an iris melanoma.

A 27-year-old white man presented with a sectoral band keratopathy overlying an iris melanoma. Clinically, it appeared as a 3 x 3-mm yellowish-white, granular subepithelial deposit in the inferonasal right cornea. Occasional small, round holes were scattered within the opacity. Clinical presentation of this lesion is described, and this unusual cause of band keratopathy is discussed.

Adult↗
PubMed1990

A randomized study of methanol-extraction residue of bacille Calmette-Guerin as postsurgical adjuvant therapy of uveal melanoma.

A randomized controlled clinical trial of methanol-extracted residue of bacille Calmette-Guerin adjuvant treatment of posterior uveal melanoma was undertaken. Of 113 patients, 34 patients received adjuvant immunotherapy and 79 patients received no treatment. No difference in survival was observed between the adjuvant-treated group and the control group of patients. This study found that the size of the tumor was a highly significant risk factor for death caused by metastasis of uveal melanomas. The standard deviation of the nucleolar area of the neoplastic cells was a significant risk factor, even though patients with tumors composed of Callender's spindle-type cells were not included in the study.

Adjuvants, Immunologic↗
PubMed1990

Comparison of xenon arc and argon laser photocoagulation in the treatment of choroidal melanomas.

We analyzed the follow-up data in 38 consecutive patients with selected choroidal melanomas that were treated by photocoagulation between 1971 and 1980. Indications for treatment included photographic documentation of tumor growth or an unequivocally positive radioactive phosphorus uptake test, or both. Xenon arc photocoagulation was used in 22 patients (58%) and argon laser was used in 16 patients (42%). At the time of data analysis, the length of follow-up was at least 58 months in all patients. Although all treated tumors were initially eradicated according to ophthalmoscopic and fluorescein angiographic criteria, there was subsequent regrowth in three of the 22 patients (14%) treated with xenon photocoagulation and in ten of the 16 patients (64%) treated with argon laser. The recurrences were observed on an average of 71 months after completion of treatment in the xenon-treated group and on an average of 30 months in the argon-treated group. More treatment sessions were required in the argon laser group to achieve tumor control. Complications of vitreous hemorrhage, cystoid macular edema, and retinal detachment were greater in the xenon photocoagulation group.

Adult↗
PubMed1990

Multiple orbital neurofibromas unassociated with von Recklinghausen's disease.

A 58-year-old man with a 10-year history of right periorbital pain treated with multiple analgesics presented with slowly progressive exophthalmos of the right eye. Orbital imaging studies disclosed three separate well-defined tumors, located in the temporal fossa, the intraconal space, and within the floor of the orbit. All three tumors were removed intact and proved on histopathologic evaluation to be localized neurofibromas. The patient had complete relief of the chronic pain following removal of the tumors. We emphasize that the unusual occurrence of multiple circumscribed orbital tumors should suggest the diagnosis of neurofibroma even in the absence of von Recklinghausen's neurofibromatosis.

Humans↗
PubMed1990

The role of photocoagulation in the management of retinoblastoma.

We treated selected patients with retinoblastoma with xenon arc photocoagulation between February 1974 and August 1987. Of 790 individual tumors in 410 affected eyes, 45 were treated by this technique. Overall photocoagulation alone was successful in eradicating 76% of the tumors, while in 24% of the tumors additional treatment with cryotherapy, plaque radiotherapy, external beam radiotherapy, or enucleation was necessary. In cases where the tumor was less than or equal to 3.0 mm in diameter and 2.0 mm in thickness and was confined to the sensory retina, without seeding into the adjacent vitreous, tumor destruction was achieved with photocoagulation. The mean number of photocoagulation sessions needed for complete tumor regression was 2.5. Photocoagulation alone was generally unsuccessful for tumors greater than 4.5 mm in diameter and 2.5 mm in thickness, and supplemental treatment with other modalities was often necessary in such cases. Based on observations in these patients, we point out certain misconceptions regarding photocoagulation of retinoblastomas and define our current indications and contraindications for this treatment modality.

Adolescent↗
PubMed1990

Solitary orbital involvement with juvenile xanthogranuloma.

A newborn girl was noted to have a smooth superonasal orbital and preseptal mass at the time of birth. The mass enlarged slightly over 3 months and a biopsy revealed histiocytes and Touton giant cells, compatible with juvenile xanthogranuloma. The infant had no other manifestations of juvenile xanthogranuloma. The mass subsided after systemic corticosteroid therapy was administered. Solitary orbital involvement with juvenile xanthogranuloma is exceedingly rare and most of these patients are found to lack the typical cutaneous lesions. Observation, oral prednisone, or low-dose radiotherapy are recommended forms of treatment.

Adrenal Cortex Hormones↗
PubMed1990

Removal of radiation-induced cataracts in patients treated for retinoblastoma.

Experience with removal of radiation-induced cataract in patients treated for retinoblastoma is limited. We retrospectively reviewed the records of 38 patients with retinoblastoma (42 eyes) who underwent removal of radiation-induced cataract from 1973 to 1989. Nineteen eyes (45%) without macular tumors or severe radiation complications had final visual acuities in the range of 20/20 to 20/50. One eye (2.4%) developed a rhegmatogenous retinal detachment and four eyes (9.5%) were noted to have amblyopia after cataract removal. Three eyes (7%) developed retinoblastoma recurrence, one with extension of retinoblastoma into the subconjunctival space through the previous sclerotomy. Exenteration was performed and the patient was alive after 8 years. Cataract removal can be visually beneficial in selected patients with radiation-induced cataracts.

Adolescent↗
PubMed1990

Enucleation after plaque radiotherapy for posterior uveal melanoma. Histopathologic findings.

A review of 1019 patients with posterior uveal melanomas, who were treated with episcleral plaque radiotherapy between April 1976 and December 1987, showed that 59 (6%) of these patients have thus far required enucleation of the affected eye. The most common clinical reasons for enucleation were tumor regrowth (51%) and neovascular glaucoma (31%). These irradiated melanomas were of mixed cell type in 40 cases (68%), spindle in 10 cases (17%), totally necrotic in 7 cases (12%), and epithelioid in 2 cases (3%). Some degree of tumor necrosis was seen in all cases. Overall, the median number of mitoses per 40 high-power fields in these irradiated tumors was 0. Most (64%) of the tumors had no identifiable mitosis in 40 high-power fields. A three-way simultaneous comparison of the following groups was made: irradiated eyes enucleated for tumor regrowth, irradiated eyes enucleated for neovascular glaucoma, and a matched group of nonirradiated posterior uveal melanomas. This comparison showed that the largest tumor dimension was significantly greater in the irradiated eyes enucleated for tumor regrowth than in the other two groups. Mitotic activity was significantly higher in the irradiated tumor regrowth and nonirradiated groups than in the irradiated neovascular group. There was no significant difference among the three groups in an analysis of height. The results suggested that mitotic activity may exist after plaque radiotherapy, especially when there is clinical evidence of tumor regrowth.

Brachytherapy↗
PubMed1990

Color Doppler imaging in the management of intraocular tumors.

Forty-four intraocular mass lesions were studied using a new, non-invasive ultrasound technique known as color Doppler imaging (CDI). This technique displays color-encoded Doppler flow information throughout a two-dimensional gray scale image thus providing selective analysis of Doppler spectra in small vessels using pulsed Doppler. Abnormal Doppler shifts were demonstrated within 39 neoplastic lesions studied, but Doppler shifts could not be detected in three tumor-simulating lesions. In a group of 12 choroidal melanomas studied after radiation therapy, lower Doppler shifts were seen compared with a group of 28 tumors before therapy. This change in Doppler shift may reflect the decreased vascular supply of the tumor. Color Doppler imaging may be of value as an additional useful tool in the diagnosis and management of intraocular tumors.

Adolescent↗
PubMed1990

Cystic adenoma of the pigmented ciliary epithelium. Clinical, pathologic, and immunohistopathologic findings.

A 51-year-old white man was found to have a deeply pigmented mass in the ciliary body and peripheral choroid of his right eye with an associated vitreous hemorrhage. Although the tumor appeared to be a ciliochoroidal melanoma, a melanocytoma and adenoma of the pigment epithelium also were considered in the differential diagnosis. The tumor was removed by a large partial lamellar sclerocyclochoroidectomy. Results of histopathologic evaluation showed a cystic adenoma of the pigmented ciliary epithelium. To the authors' knowledge, this was the first immunohistopathologic study of this tumor. Results of the study showed marked immunoreactivity for low molecular weight cytokeratins, vimentin, and S-100 protein. These immunohistochemical studies are consistent with the origin of this tumor from pigment epithelial cells.

Antibodies, Monoclonal↗
PubMed1990

Congenital hypertrophy of the retinal pigment epithelium. Electron microscopic and morphometric observations.

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a well-circumscribed, flat, pigmented fundus lesion that is stable and generally nonprogressive. Light and electron microscopy and morphometric analysis was used to study a lesion with the clinical characteristics of CHRPE found in an eye enucleated for a posterior segment malignant melanoma. These studies showed that the lesion was composed of tall, maximally pigmented RPE cells that had a density 1.7 times greater than the density of the adjacent normal peripheral RPE. These observations suggested that cellular hyperplasia and hypertrophy may contribute to CHRPE. Ultraviolet fluorescence microscopy showed no autofluorescent granules of lipofuscin in the CHRPE, suggesting that the lesion's constituent cells lack the capacity to phagocytose and digest photoreceptor outer segments. Photoreceptor degeneration in the overlying retina consequent to this functional defect could be responsible for the localized visual field defects that typically occur in patients with CHRPE.

Choroid Neoplasms↗