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Biomedical subjects

C L Shields

Publications and source records attributed to C L Shields.

At least 109 records · Page 6Linked to original sources
PubMed1999

Adenoma of the ciliary body pigment epithelium: the 1998 Albert Ruedemann, Sr, memorial lecture, Part 1.

BACKGROUND: Adenoma of the pigment epithelium of the ciliary body (CPE) is a rare neoplasm. Most reported cases have been misdiagnosed as ciliary body melanoma. OBJECTIVES: To evaluate clinical features, management, pathological features, and prognosis of adenoma of the CPE and to determine clinical features that may differentiate it from ciliary body melanoma. PATIENTS AND METHODS: A retrospective review was performed of medical charts, photographs, and pathological features of patients with adenoma of the CPE who were treated by the authors. RESULTS: Of the 8 patients with adenoma of the CPE, 3 were male and 5 were female. Seven were white, and 1 was Asian. The mean age at diagnosis was 51 years (range, 8-73 years). The referring diagnosis was ciliary body melanoma in 7 patients and cyst in 1 patient. The lesions were all solitary and unilateral and ranged from 3 x 3 x 3 to 13 x 13 x 8 mm. Clinically, all tumors were gray to black, had abruptly elevated margins, and were dome shaped. Associated findings included secondary cataract (6 patients) and vitreous hemorrhage (1 patient). Results of ancillary studies such as transillumination, fluorescein angiography, and ultrasonography showed patterns that were helpful in differentiation from ciliary body melanoma. Fine needle aspiration biopsy, performed in 3 patients, was an accurate diagnostic adjunct. Microscopic diagnosis was adenoma of the CPE in 7 cases in which tissue was available. A consistent histopathologic feature was the presence of typical clear vacuoles within the tumor. One tumor invaded the sensory retina. Results of immunohistochemical studies were consistent with a tumor of neuroectodermal origin. CONCLUSIONS: Adenoma of the CPE has characteristic features that may help differentiate it from ciliary body melanoma. In contrast to melanoma, it is generally darker and its margins are more abruptly elevated. Although it is benign cytologically, it can exhibit growth. If the diagnosis is suspected, removal of the tumor by local resection is advisable.

Adenoma↗
PubMed1999

Neoplasms of the retinal pigment epithelium: the 1998 Albert Ruedemann, Sr, memorial lecture, Part 2.

BACKGROUND: Neoplasms of the retinal pigment epithelium (RPE) are rare, and little is known about their clinical variations, clinical course, and prognosis. Although most are benign, they can simulate choroidal melanoma. OBJECTIVES: To evaluate the clinical characteristics, management, pathological features, and prognosis of acquired neoplasms of the RPE (adenoma and adenocarcinoma) and to define clinical features that help differentiate them from uveal melanoma. PATIENTS AND METHODS: The medical records of patients with acquired tumor of the RPE were reviewed retrospectively, and the clinical features, management, and histopathologic findings were studied. RESULTS: Of 13 affected patients, 10 were women and 3 were men. Ten were white and 3 were African American. The mean age at diagnosis was 53 years (range, 28-79 years). All patients were referred with the diagnosis of suspected choroidal melanoma. All tumors were solitary, unilateral, and ranged from a small, asymptomatic lesion measuring 2 x 2 x 1 mm to a massive neoplasm that measured 17 x 17 x 17 mm. There was no predilection for retinal location or laterality. The tumors were dark brown to black in 11 patients and only minimally pigmented in 2. Prominent retinal feeder vessels were visualized in 8 patients, 5 of whom had an exudative retinal detachment. Two patients had recurrent vitreous hemorrhage. Transillumination generally revealed blockage of light by the tumor. Fluorescein angiography showed early hypofluorescence and late minimal hyperfluorescence of the tumor, without visibility of choroidal vessels. Ultrasonography typically demonstrated the tumor to be abruptly elevated and to have medium to high internal reflectivity and acoustic solidity. Results of diagnostic fine needle aspiration biopsy, performed on 4 patients, disclosed cells compatible with a pigment epithelial origin. Treatment ultimately included observation in 4 patients, enucleation in 3, local tumor resection in 3, irradiation in 2, and laser therapy in 1. Microscopic verification of the diagnosis was available in 3 eyes after fine needle aspiration biopsy, 3 eyes after local resection, 3 eyes after enucleation, and 1 eye post mortem. The microscopic diagnosis was adenoma in 8 patients and adenocarcinoma in 2. Microscopically, the lesions were composed of a neoplastic proliferation of RPE cells. Tumors arising from the anterior portion of the RPE had a vacuolated pattern, and those in the posterior portion of the RPE had a glandular or tubular configuration. CONCLUSIONS: Neoplasms of the RPE show considerable clinical variation. In contrast to melanoma, they generally are darker, more abruptly elevated, and more likely to have retinal feeder vessels and exudative retinal detachment; show early hypofluorescence and mild late hyperfluorescence on angiographic findings; and have high internal reflectivity on ultrasonographic findings. Although most acquired tumors of the RPE are benign cytologically, they can exhibit aggressive clinical behavior.

Adenocarcinoma↗
PubMed1999

Radiation retinopathy following plaque radiotherapy for posterior uveal melanoma.

OBJECTIVE: To identify the risk factors that lead to the development of radiation retinopathy following plaque radiotherapy for posterior uveal melanoma. Radiation retinopathy is a slowly progressive, occlusive vasculopathy characterized by radiation-induced endothelial damage. METHODS: Review of the medical records of patients with posterior uveal melanoma treated with plaque radiotherapy. RESULTS: Of 1300 patients with posterior uveal melanoma treated with plaque radiotherapy from July 1, 1976, through June 30, 1992, radiation retinopathy developed in 560 (43.1%). By using Kaplan-Meier survival estimates, we found that 5% of the patients had nonproliferative radiation retinopathy at 1 year (95% confidence interval [CI], 3%-6%) and 42% at 5 years (95% CI, 38%-45%). The proportion of patients with proliferative retinopathy was 1% at 1 year (95% CI, 0.2%-1.5%) and 8% at 5 years (95% CI, 5%-10%). Multivariate analyses showed that the subset of clinical variables best related to the development of nonproliferative radiation retinopathy were tumor margin of less than 4 mm from foveola (P<.001), tumor limited to the choroid (P = .002), and radiation dose rate of greater than 260 cGy/h to the tumor base (P = .02). The best subset of independent variables related to the development of radiation maculopathy were tumor of less than 4 mm to foveola (P<.001) and the use of radioisotope iridium 192 (192Ir) (P = .02) compared with iodine 125 (125I). From a multivariate model, the most important factors for the development of proliferative radiation retinopathy included diabetes mellitus (P = .01), radioisotope 192Ir (P = .01) compared with 125I, and tumor base of greater than 10 mm (P = .02). CONCLUSIONS: Radiation retinopathy is a common finding after plaque radiotherapy for choroidal melanoma, occurring in 42% of patients at 5 years. The main predictors of radiation retinopathy are posterior tumor location with margin near the foveola and high radiation dose rate to the tumor base.

Adult↗
PubMed1999

Adenoma of the iris pigment epithelium: a report of 20 cases: the 1998 Pan-American Lecture.

BACKGROUND: Adenoma of the iris pigment epithelium (IPE) is an uncommon lesion that can simulate iris or ciliary body melanoma, melanocytoma, and pigment epithelial cyst. OBJECTIVES: To evaluate the clinical and pathological features and prognosis of adenoma of the IPE in patients managed by us and to elucidate the features that help to differentiate this tumor from iris melanoma and other similar conditions. PATIENTS AND METHODS: The medical records of 20 patients with adenoma of the IPE were reviewed, and the clinical and histopathologic features were tabulated. RESULTS: Ten patients were male and 10 were female, with a mean age of 60.0 years (range, 11-85 years). All patients were referred because of suspected iris or ciliary body melanoma. All lesions were solitary and unilateral. Sixteen were located in the peripheral iris; 2, in the midzone; and 2, near the pupillary margin. Clinically, all tumors were abruptly elevated, all but 1 were dark gray to black, and all had a smooth, but sometimes multinodular, surface. The tumors caused thinning or complete effacement of the overlying iris stroma, but they did not directly involve the stroma. They typically blocked light with transillumination. On ultrasound biomicroscopy findings, adenoma of the IPE shows a solid tumor pattern, sometimes with small cystoid spaces. The tumor was managed by local resection in 2 patients and observation in 18, all of whom have been stable, with follow-up ranging from 6 months to 9 years. Histopathologic examination revealed a tumor originating in the IPE consisting of cords of pigment epithelial cells separated by septae of connective tissue. CONCLUSIONS: Adenoma of the IPE usually has characteristic features that should differentiate it from iris melanoma, ciliary body melanoma, iris melanocytoma, and iris cyst. Adenoma of the IPE is a benign tumor that may remain relatively stable for years.

Adenoma↗
PubMed1999

Thermotherapy for retinoblastoma.

OBJECTIVE: To evaluate the results of thermotherapy for retinoblastoma. DESIGN: Prospective, nonrandomized analysis of the treatment method. PARTICIPANTS: A total of 188 retinoblastomas in 80 eyes of 58 patients who were treated with thermotherapy. MAIN OUTCOME MEASURES: Tumor response and ocular adverse effects. RESULTS: Of 188 retinoblastomas treated with thermotherapy, mean tumor base was 3.0 mm and tumor thickness was 2.0 mm. Complete tumor regression was achieved in 161 tumors (85.6%), and 27 tumors (14.4%) developed recurrence. Using univariate analysis, the predictors of local tumor recurrence were male sex (P = .005), no color change ("no visible take") in tumor after treatment (P = .01), increasing number of treatment sessions (P = .002), and previous use of chemoreduction (P = .02). By multivariate analysis, the most important predictors of local tumor recurrence were male sex (P = .01) and previous use of chemoreduction (P = .03), the latter likely reflecting the fact that these tumors were initially larger with more ominous findings, and required chemoreduction therapy to reduce them to a size amenable to focal treatment with thermotherapy. When evaluating thermotherapy variables as a function of tumor size, it was apparent that larger tumors (> or =3.0-mm base) required greater energy and time than did smaller tumors (<3.0-mm base). Comparison of treatment variables for larger vs smaller tumors was as follows: number of treatment sessions, 3.3 vs 2.3; spot size, 1.7 vs 1.3 mm; power, 540 vs 370 mW; treatment duration, 49 vs 14 minutes; and coupling of thermotherapy with chemotherapy, 79% vs 48% of cases (P < or =.001 for each variable). Complications of thermotherapy in the 80 eyes included focal iris atrophy in 29 eyes (36%), peripheral focal lens opacity in 19 eyes (24%), retinal traction in 4 eyes (5%), retinal vascular obstruction in 2 eyes (2%), and transient localized serous retinal detachment in 2 eyes (2%). There were no cases of corneal scarring, central lens opacity, iris or retinal neovascularization, or rhegmatogenous retinal detachment. All eyes with focal lens opacity demonstrated adjacent focal iris atrophy. By multivariate analysis, the predictors of thermotherapy-induced focal iris atrophy were increasing number of treatment sessions (P = .001) and increasing tumor base (P = .02). CONCLUSIONS: Thermotherapy is used for relatively small retinoblastomas without associated vitreous or subretinal seeds. This treatment provides satisfactory control for selected retinoblastomas, with 86% of tumors demonstrating lasting regression. Tumors that measure 3.0 mm or larger in base at the time of thermotherapy require more intense treatment than smaller tumors and are at greatest risk for ocular complications such as focal iris atrophy and focal paraxial lens opacity.

Chemotherapy, Adjuvant↗
PubMed1999

Giant cell reparative granuloma of the orbit.

PURPOSE: To report a case of giant cell reparative granuloma occurring in the orbit and to discuss its clinical, radiologic, and histopathologic characteristics in contrast with other similar lesions. METHODS: A 38-year-old man developed pain and mild proptosis of the left eye. Computed tomography and magnetic resonance imaging demonstrated an intraosseous cystic orbital mass. Excisional biopsy disclosed giant cell reparative granuloma of the orbit. RESULT: At 11 months' follow-up, the patient had normal vision, with no tumor recurrence. CONCLUSION: Giant cell reparative granuloma of the orbit is a rare benign fibro-osseous proliferation that is generally seen in young adulthood. It should be considered in the differential diagnosis of orbital fibro-osseous proliferation. Surgical excision and curettage is the therapeutic method of choice.

Adult↗
PubMed1999

Radiation complications and tumor control after plaque radiotherapy of choroidal melanoma with macular involvement.

PURPOSE: To determine the outcome of plaque radiotherapy in the treatment of macular choroidal melanoma and to identify the risk factors associated with the development of radiation complications, tumor recurrence, and metastasis. METHODS: Chart analysis of 630 consecutive patients (630 eyes) with macular choroidal melanoma managed by plaque radiotherapy between July 1976 and June 1992. RESULTS: The median largest basal tumor diameter was 10 mm, and the median tumor thickness was 4 mm. By means of Kaplan-Meier estimates, visually significant maculopathy developed at 5 years in 40% of the patients, cataract in 32%, papillopathy in 13%, and tumor recurrence in 9%. Vision decrease by 3 or more Snellen lines was found in 40% of the patients at 5 years. Sixty-nine eyes (11%) were enucleated because of radiation complications and recurrence. Twelve percent of the patients developed metastasis by 5 years and 22% by 10 years. Results of multivariate Cox proportional hazards analyses showed that the significant predictors for tumor recurrence were a distance of tumor margin from the optic disk of less than 2 mm (P = .003) and retinal invasion (P = .009). The significant variables that were predictive of metastasis included tumor thickness greater than 4 mm (P = .02) and largest basal tumor diameter greater than 10 mm (P = .03). CONCLUSIONS: Plaque radiotherapy offers a 91% 5-year local tumor control rate for macular choroidal melanoma. Despite good local tumor control, the risk for metastasis is 12% at 5 years and 22% at 10 years. In 11% of the patients, enucleation eventually became necessary because of radiation complications and tumor recurrence.

Adult↗
PubMed1999

Oral cimetidine (Tagamet) for recalcitrant, diffuse conjunctival papillomatosis.

PURPOSE: To report the efficacy of cimetidine for treatment of conjunctival papillomatosis. METHODS: An 11-year-old boy had an 8-year history of diffuse conjunctival papillomas, treated previously with standard measures of excisional biopsy and cryotherapy. He developed spontaneous conjunctival bleeding and diffuse tumor recurrence over the entire conjunctival surface. Oral cimetidine liquid (30 mg/kg/day) was prescribed. RESULTS: Within 2 months, dramatic tumor regression was noted, with nearly complete resolution by 4 months. The patient had no local or systemic side effects from the medication. CONCLUSIONS: Oral cimetidine possesses immune modulation properties and may be useful in some cases of virus-induced conjunctival papillomatosis.

Adjuvants, Immunologic↗
PubMed1999

Extraocular extension of unrecognized choroidal melanoma simulating a primary optic nerve tumor: report of two cases.

BACKGROUND: Orbital extraocular extension of choroidal melanoma is well known and is usually detected in eyes with medium and large tumors, but it is very rare with small melanomas. It is particularly unusual for choroidal melanomas of any size to invade the optic nerve or its meninges. DESIGN: Two case reports. PARTICIPANTS: Two patients with small, relatively inconspicuous juxtapapillary pigmented choroidal lesions were referred with the diagnosis of primary optic nerve tumor. Both demonstrated a large nodular tumor in the meninges of the optic nerve, immediately posterior to the globe. METHODS: Retrospective review of clinical records and histopathology. RESULTS: In both cases, orbital magnetic resonance imaging confirmed the presence of a hyperintense enhancing nodular mass near the anterior portion of the optic nerve, prompting optic nerve biopsy in one case. Subsequent fundus examination disclosed a small juxtapapillary pigmented choroidal lesion measuring 1.0 mm or less in thickness. These observations suggested that the optic nerve tumor might be nodular extraocular extension of a small choroidal melanoma. Modified enucleation was performed in both cases, and histopathologic examination revealed a nodule of malignant melanoma within the meninges that compressed the optic nerve and extended extraocularly from a small, relatively inapparent juxtapapillary choroidal melanoma. In both cases, the extraocular component was large and symptomatic, whereas the intraocular component was inconspicuous. CONCLUSIONS: Small juxtapapillary choroidal melanomas can exhibit prominent extension into the orbit. All patients with orbital tumors should have careful ophthalmoscopy.

Aged↗
PubMed1999

Invasive giant cell astrocytoma of the retina in a patient with tuberous sclerosis.

OBJECTIVE: To report an unusual case of giant cell astrocytoma of the retina. DESIGN: Case report. INTERVENTION: A 10-month-old girl with tuberous sclerosis was found to have bilateral astrocytic hamartomas, the right eye being prominently involved by elevated and pedunculated lesions. At 7 years of age, she had posterior subcapsular cataract, retinal detachment, and subretinal exudation develop in the right eye. At 12 years of age, her blind, painful right eye had to be enucleated because of neovascular glaucoma and a spontaneous scleral perforation. RESULTS: Histopathologic examination showed that the entire vitreous cavity was filled with a mixture of tumor, granulation tissue, and necrotic debris. Part of the tumor was composed of spindle-shaped glial cells. The remainder was composed of large gemistocytic cells that contained large atypical nuclei and copious amounts of cytoplasm, which was intensely eosinophilic in some areas. The tumor contained foci of necrosis and rare mitotic figures. It had infiltrated the parenchyma of the retrolaminar nerve and extended to the surgical margin. Areas of unequivocal choroidal invasion were also identified. The tumor cells were intensely immunoreactive for neuron-specific enolase and S-100 protein. In contrast, glial fibrillary acidic protein was only minimally positive. CONCLUSIONS: The histologic and immunohistochemical features of this retinal tumor resemble those of subependymal giant cell astrocytoma, a characteristic lesion in tuberous sclerosis. Although this unusual giant cell astrocytoma of the retina had atypical histopathologic features and local aggressive behavior, the systemic prognosis was excellent.

Astrocytoma↗
PubMed1999

The 1998 Pan American Lecture. Intraocular invasion of conjunctival squamous cell carcinoma in five patients.

PURPOSE: To report five patients with intraocular invasion of conjunctival squamous cell carcinoma and to make recommendations regarding clinical recognition and treatment of this condition. METHODS: The authors reviewed the clinical records and pathology slides on five patients who had intraocular invasion of conjunctival squamous cell carcinoma, and they describe the presenting features and histopathology in these cases. RESULTS: Intraocular invasion of conjunctival squamous cell carcinoma occurred in older patients who had one or more recurrences of a previously excised conjunctival epithelial tumor located near the comeoscleral limbus. The intraocular recurrence often was heralded by the onset of low-grade inflammation and secondary glaucoma, simulating a granulomatous iridocyclitis. A white mass generally was observed in the anterior chamber angle. Histopathologic examination revealed an ingrowth of malignant epithelial cells through the limbus with diffuse involvement of the anterior segment of the eye. The reported patients were managed by modified enucleation (standard enucleation with excision of affected conjunctival tissue). Metastatic disease did not develop in any of the patients. CONCLUSIONS: The onset of signs of uveitis and glaucoma and a white mass in the anterior chamber angle in a patient with prior excision of a conjunctival squamous cell neoplasm tumor should raise suspicion of intraocular recurrence of conjunctival squamous cell carcinoma. Most affected patients require enucleation or subtotal orbital exenteration. The prognosis is good.

Aged↗
PubMed1999

Transpupillary thermotherapy for choroidal melanoma.

The management of choroidal melanomas depends on many factors, most importantly, tumor size and location. Small choroidal melanoma in the posterior fundus is amenable to treatment options such as enucleation, radiotherapy, laser photocoagulation, and transpupillary thermotherapy or a combination of these methods. Transpupillary thermotherapy is a technique of tumor heating by infrared radiation delivered through the pupil into the tumor. This method causes dramatic tumor necrosis in choroidal melanomas up to 4 mm in thickness. With properly selected small choroidal melanomas, tumor control is approximately 94%. The heat induces cellular damage at the site of treatment with few remote side effects; therefore, complications are generally limited to the site of treatment and include retinal vascular obstruction (23%), retinal traction (20%), retinal neovascularization (6%), and retinal hole with detachment (< 1%). Tumors located temporal to the foveola demonstrate a statistically higher risk for retinal traction than those located in other quadrants. Tumors near the optic disk demonstrate a higher incidence of retinal neovascularization due to heat-induced obstruction of a major retinal vascular arcade. Overall, vision preservation is satisfactory after thermotherapy for choroidal melanoma, with more than 50% of patients maintaining the same or better vision after treatment, depending primarily on tumor location. In summary, small choroidal melanomas can be controlled with transpupillary thermotherapy, especially those near the optic disk and foveola in areas that are otherwise difficult to irradiate. Longer follow-up is necessary to assess for local recurrence and the impact of treatment on life prognosis.

Animals↗
PubMed1999

Iris cysts in children: classification, incidence, and management. The 1998 Torrence A Makley Jr Lecture.

BACKGROUND: Iris cysts in children are uncommon and there is relatively little information on their classification, incidence, and management. METHODS: The records of all children under age 20 years who were diagnosed with iris cyst were reviewed and the types and incidence of iris cysts of childhood determined. Based on these observations recommendations were made regarding management of iris cysts in children. RESULTS: Of 57 iris cysts in children, 53 were primary and four were secondary. There were 44 primary cysts of the iris pigment epithelium, 34 of which were of the peripheral or iridociliary type, accounting for 59% of all childhood iris cysts. It was most commonly diagnosed in the teenage years, more common in girls (68%), was not recognised in infancy, remained stationary or regressed, and required no treatment. The five mid-zonal pigment epithelial cysts were diagnosed at a mean age of 14 years, were more common in boys (83%), remained stationary, and required no treatment. The pupillary type of pigment epithelial cyst was generally recognised in infancy and, despite involvement of the pupillary aperture, also required no treatment. There were nine cases of primary iris stromal cysts, accounting for 16% of all childhood iris cysts. This cyst was usually diagnosed in infancy, was generally progressive, and required treatment in eight of the nine cases, usually by aspiration and cryotherapy or surgical resection. Among the secondary iris cysts, two were post-traumatic epithelial ingrowth cysts and two were tumour induced cysts, one arising from an intraocular lacrimal gland choristoma and one adjacent to a peripheral iris naevus. CONCLUSIONS: Most iris cysts of childhood are primary pigment epithelial cysts and require no treatment. However, the iris stromal cyst, usually recognised in infancy, is generally an aggressive lesion that requires treatment by aspiration or surgical excision.

Adolescent↗