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P T Finger

Publications and source records attributed to P T Finger.

At least 55 records · Page 3Linked to original sources
PubMed1998

Three-dimensional ultrasonography of choroidal melanoma: localization of radioactive eye plaques.

OBJECTIVE: To evaluate the use of 3-dimensional (3D) ultrasonography for the localization of episcleral eye plaques during the treatment of choroidal melanomas. METHODS: A series of 13 patients with choroidal melanoma were treated with radioactive palladium 103 seeds affixed into gold eye plaques. During surgery, 3D ultrasonography was performed with a commercially available system to evaluate the relative position of radioactive plaques secured beneath their intraocular tumors. This system consists of an automated, rotating, handheld, B-scan ultrasonographic probe operating at 10 MHz, a personal computer, and 3D imaging software. RESULTS: We measured the margins of the plaque extending beyond the tumor and the distance between the radioactive seeds and the tumor apex. We also evaluated the relationship between the plaque edge, the episclera, and the tumor's edges. While the plaques were well centered over the tumor in all cases, the plaque margins around the tumor were found to be variably sized. When comparing measurements taken at the time of plaque insertion with those taken at the time of plaque removal, we noted changes in the apical tumor height and in plaque centration. In the 1 patient with a juxtapapillary tumor, the posterior margin of the plaque was found to be displaced away from the sclera, or "tilted." CONCLUSIONS: Three-dimensional ultrasonography offers a new method for ophthalmic plaque localization. Unique perspectives can be visualized through the use of computer-aided 3D reconstructions that permit the assessment of the relative position of the plaque to the optic nerve and the measurement of the distance between the in vivo radioactive seed and the tumor apex. Our experience suggests that when compared with 2-dimensional ultrasonography, 3D ultrasonography offers new capabilities that can be used to improve plaque placement and radiation dose calculations.

Brachytherapy↗
PubMed1998

Three-dimensional ultrasonography of choroidal melanoma: extrascleral extension.

PURPOSE: To describe the results of three-dimensional ultrasonography used to evaluate extrascleral extension of a choroidal melanoma. METHODS: Case report. The three-dimensional ultrasound system uses a 10-MHz B-mode transducer combined with a motorized rotating holder. The system acquires 180 sequential images that are stored and processed to create a three-dimensional block of the region of interest. RESULTS: Unique coronal and oblique perspectives were obtained from interactive manipulation of the three-dimensional reconstruction. Examination of the three-dimensional image allowed us to detect the transscleral uveal-orbital connection. Extrascleral melanomatous extension was confirmed on histopathologic examination. CONCLUSION: Three-dimensional ultrasonography is a promising imaging technique for evaluating melanomatous extrascleral extension.

Choroid Neoplasms↗
PubMed1998

Topical mitomycin C chemotherapy for conjunctival melanoma and PAM with atypia.

AIM: To evaluate topical mitomycin C (MMC) chemotherapy in the treatment of conjunctival melanoma and primary acquired melanosis with atypia. METHODS: In a phase I clinical trial, 10 patients with conjunctival melanoma and/or primary acquired melanosis with atypia were treated with topical MMC 0.04% four times daily. Four patients were given MMC for 28 days as a primary treatment. Six patients were treated with MMC for 7 days after excision and cryotherapy in an effort to improve local control. In this series, 10 patients have been followed for an average of 29 months. RESULTS: All patients were noted to develop transient keratoconjunctivitis during treatment. One patient also developed a transient corneal epithelial defect. Decreased conjunctival pigmentation was noted in the four patients where topical chemotherapy was used as a primary treatment. Nodular tumours were resistant to topical MMC chemotherapy. Of the six patients treated within 2 weeks after primary excision and cryotherapy, there has been no tumour recurrence or symblepharon formation. Nine of the 10 study patients have maintained within one line of their pretreatment visual acuity. No retinal or optic nerve toxicity was noted. CONCLUSION: Since no complications which might preclude further investigation of topical MMC chemotherapy occurred, it was concluded that topical MMC chemotherapy was tolerated as a treatment for conjunctival melanoma and primary acquired melanosis with atypia.

Administration, Topical↗
PubMed1998

Ultrasound biomicroscopy in the diagnosis and management of anterior segment tumors.

BACKGROUND: High-frequency ultrasound biomicroscopy has allowed eye care specialists to evaluate posterior extension of anterior segment tumors. This article evaluates the role of ultrasound biomicroscopy for the diagnosis and management of anterior segment tumors. METHODS: Fourteen patients with anterior segment tumors were selected for evaluation. Each patient underwent a complete clinical examination followed by slit-lamp photography and ultrasound biomicroscopy. RESULTS: Unlike standard ultrasonography of anterior segment tumors, high-frequency ultrasound biomicroscopy allowed quantitative measurements of tumor size, extension within and posterior to the iris, as well as differentiation of solid and cystic lesions. These characteristics were used to differentially diagnose anterior segment tumors and document the response of iridociliary body melanomas to radiotherapy. CONCLUSIONS: This study demonstrates how ultrasound biomicroscopy has become an effective and necessary procedure, used for both the diagnosis and management of anterior segment tumors.

Adult↗
PubMed1997

Microwave thermoradiotherapy for uveal melanoma: results of a 10-year study.

OBJECTIVE: The purpose of the study is to evaluate clinically the use of microwave-heating (hyperthermia) as an adjuvant to ophthalmic plaque irradiation for treatment of patients with uveal melanoma. Hyperthermia was also used as a radiation sensitizer, allowing for significant dose reductions during ophthalmic plaque radiation therapy. PARTICIPANTS: In this case series, 48 patients were treated with microwave plaque thermotherapy for uveal melanoma. INTERVENTION: Microwave treatment, which involved affixing a miniature microwave dish antenna on the sclera beneath the tumor after completion of plaque brachytherapy, was performed. During hyperthermia treatment, the tumor's apex was targeted to receive a minimum of 42 degrees C for a 45-minute duration. A subset of 38 (79%) were given reduced apical doses of ophthalmic plaque radiation (radioactive isotope of iodine [125I] or palladium-103 [103Pd]) to an average of 52.6 Gy. MAIN OUTCOME PARAMETERS: Patients were evaluated for visual function, microwave toxicity, radiation oculopathy, eye retention, local tumor control, and metastatic disease. RESULTS: Patients have been observed for up to 10 years and for an average of 60 months (5 years). To date, there have been 3 cases of postoperative tumor enlargement (growth) for a 93.8% local control rate. Two patients were lost to follow-up. Seven eyes have been enucleated: three due to neovascular glaucoma, one due to uveitic neovascular glaucoma, and three due to progressive tumor enlargement. Although 15 patients have died, only 4 deaths were because of metastatic choroidal melanoma. Of the original 48 patients, 33 (69%) have maintained within 2 lines or have better than their preoperative visual acuity. Side effects attributable to heating have included decreased intraocular pressure without hypotony as well as chorioretinal scar formation within and around the targeted zone. CONCLUSIONS: The results of this series suggest that adjuvant microwave thermotherapy can be used with reduced doses of ophthalmic plaque radiation therapy to control the growth of uveal melanomas. Although the incidence of neovascular glaucoma, enucleation, and tumor regrowth is comparable to that of other series evaluating radiation alone, the visual acuities of microwave plaque thermotherapy-treated eyes were found to be superior.

Body Temperature↗
PubMed1996

Radiotherapy for age-related macular degeneration: preliminary results of a potentially new treatment.

PURPOSE: Neovascular macular degeneration is the leading cause of severe blindness in North America today. Limited treatments are available for this disease process. A Phase I/II study was performed to determine the toxicity and efficacy of external beam radiotherapy in patients with age-related subfoveal neovascularization. METHODS AND MATERIALS: Between March 1994 and June 1995, 52 patients with a mean age of 80 (60-92) were enrolled. These patients were either not eligible or were poor candidates for laser photocoagulation, primarily because of the subfoveal location of the neovascularization. Initial visual acuities ranged from 20 out of 32 to finger counting at 3 feet. All patients underwent fluorescein angiographic evaluation and documentation of their neovascular disease prior to irradiation. Patients were treated with a single lateral 4- or 6-MV photon beam, to a dose of 14-15 Gy in eight fractions over 10 days. The field size averaged 5 x 3 cm. RESULTS: No significant acute morbidity was noted. All patients underwent ophthalmic examinations and repeat angiography at 1 and 3 months posttreatment and then at 3-month intervals. With a mean follow-up of 7 months (3-18 months), 41 patients (79%) are within two lines of their pretreatment visual acuity. On angiographic imaging, there was stabilization of subfoveal neovascular membranes in 34 patients (65%). New neovascular membranes have been noted in five patients. CONCLUSIONS: It appears that radiotherapy can affect active subretinal neovascularization, but it is unlikely to prevent new neovascular events produced by this chronic disease. Further investigation is warranted.

Aged↗
PubMed1996

Adenocarcinoma of the retinal pigment epithelium: a diagnostic and therapeutic challenge.

BACKGROUND: Adenocarcinoma of the retinal pigment epithelium (RPE) is an uncommon intraocular tumor which has been rarely if ever diagnosed prior to enucleation. Our review of the literature suggests that when a melanotic and tuberous-shaped tumor presents in a woman with signs of uveitis one should consider the diagnosis of adenocarcinoma of the RPE. METHODS: We report a case in which a 4.9-mm-tall, mushroom-shaped, moderately reflective melanotic tumor found to be present in a 50-year-old woman. Other findings included a 12 x 10-mm dense transillumination shadow and 270 deg of posterior iris synechiae. With a presumptive diagnosis of uveal melanoma the patient was treated with palladium-103 plaque radiotherapy. Within 6 months she underwent enucleation due to uncontrollable ocular pain and progressive tumor growth. Histopathologic evaluation revealed an adenocarcinoma of the (RPE). RESULTS: Two months after radiotherapy the eye developed acute angle-closure glaucoma, secondary retinal detachment, and a painful scleritis (a result similar to that of Greer, who treated an intraocular adenoma with radiation). Our diagnosis of adenocarcinoma of the RPE was made after enucleation. CONCLUSION: Adenocarcinomas of the RPE are rarely if ever diagnosed on clinical evaluation, should be suspected in women with a melanotic intraocular tumor and uveitis, and may respond poorly to ophthalmic plaque radiotherapy. All reported cases presenting without extrascleral extension have not metastasized.

Adenocarcinoma↗
PubMed1996

Radiation therapy for subretinal neovascularization.

PURPOSE: To evaluate low-dose external beam irradiation and plaque radiotherapy for the treatment of subretinal neovascularization. METHODS: The authors treated 137 patients with radiation therapy for subretinal neovascularization. Herein, they examine a subset of 75 patients with exudative age-related macular degeneration who were treated with (4- or 6-MV photons) external beam irradiation at a dose of 1200 to 1500 cGy to the affected macula. In addition, six patients were treated with palladium 103 ophthalmic plaque brachytherapy to an equivalent retinal apex dose of 1200 to 1500 cGy. The authors compared the intralesional, intraocular, and intracranial radiation dose distributions of each treatment modality. Early Treatment Diabetic Retinopathy Study-type visual acuity determinations, ophthalmic examinations, and angiography were performed before and after treatment. Clinical evaluations were performed in a nonrandomized and unmasked fashion. RESULTS: Episcleral plaque brachytherapy was found to provide a higher average radiation dose within the neovascular tissues while delivering less radiation to most normal ocular (both eyes) and all intracranial structures. Both forms of radiotherapy were associated with decreased hemorrhages, exudates, and leakage of neovascular membranes. Ten (13 percent) patients receiving external beam radiotherapy had transient epiphora and ocular irritation. CONCLUSION: Observation and laser photocoagulation of subfoveal neovascularization have been associated with poor visual outcomes. Pilot experience suggests that low-dose radiotherapy offers a method to treat subretinal neovascularization without destroying the overlying retina. Although the authors' radiation distribution studies favored plaque radiotherapy, additional factors such as relative efficacy, expense, convenience, and safety must be investigated.

Aged↗
PubMed1996

Microwave thermoradiotherapy for intraocular melanoma.

We evaluated the use of microwave hyperthermia as an adjuvant to ophthalmic plaque radiotherapy for patients with intraocular tumors. Forty-eight patients were offered combined microwave plaque thermoradiotherapy (TRT) as a primary treatment for their uveal melanomas. A dish-shaped microwave antenna was placed on the sclera beneath the tumor at the time of plaque brachytherapy. While temperatures were measured at the sclera, the tumor's apex was targeted to receive a minimum of 42 degrees C for a 45-min duration. Patients were also given full or reduced doses of plaque radiotherapy (125I or 103Pd). We reduced the minimum tumor radiation dose (apex dose) for 42 (88%) of our patients to <70 Gy (mean, 52.5 Gy). The 48 TRT patients were followed for < or =8 years (average, 45 months). To date, there has been one documented postoperative tumor enlargement, for a 97.2% local control rate. Two patients were lost to follow-up. Four eyes have been enucleated: two due to neovascular glaucoma, one to glaucoma secondary to intraocular inflammation, and one for progressive tumor enlargement. Although 13 patients have died, only four deaths were due to metastatic melanoma. Thirty-five patients (73%) have maintained within two lines or had better than their preoperative visual acuity. Side effects attributable to heating included chorioretinal scar formation within and around the targeted zone and decreased intraocular pressures without hypotony. Our experience with this heat delivery system suggests that adjuvant microwave thermotherapy can be used with plaque radiotherapy for the treatment of uveal melanoma.

Humans↗
PubMed1995

Epithelial inclusion cyst of the iris.

We describe the clinical presentation, high-frequency ultrasound biomicroscopic characteristics, and pathologic findings associated with a conjunctival inclusion cyst within the iris. The patient had undergone an uncomplicated extracapsular cataract extraction with posterior chamber intraocular lens insertion 9 months prior to presenting with a progressively enlarging iris mass. A clinical examination revealed a solid-appearing white tumor within the midiris stroma, accompanied by limbal-conjunctival hyperemia and anterior chamber inflammation. Ultrasound biomicroscopy revealed an egg-shaped solid iris stromal tumor that displaced the pigment epithelium. The mass was composed of three concentric layers of different echogenicity: a moderately reflective mantle, a less reflective middle zone, and a hyperreflective core. Within 3 days of initiation of topical corticosteroid therapy (prednisolone acetate, 0.5 mg per drop four times daily), the tumor enlarged and induced a plasmoid aqueous and a hypopyon. Histopathologic study revealed a conjunctival inclusion cyst with evidence of acute and chronic inflammation. We have found that the diagnosis of epithelial inclusion cyst within the iris can be aided by an ultrasound evaluation. This case also suggests that it may be preferable to excise these tumors prior to topical corticosteroid treatment.

Aged↗
PubMed1995

Microwave cyclodestruction: evaluation on human eyes.

AIMS: The study was set up to evaluate the effect of microwave cyclodestruction on human eyes. METHODS: Two human eyes were studied. For treatment a horn shaped 5.8 GHz microwave applicator and fibre optic thermometry were used. Just before enucleation, the rectangular (2 x 3 mm) microwave aperture was placed onto the conjunctiva at a position 1-2 mm posterior to the corneal scleral limbus. Each of three to four treatment spots was targeted to receive a thermal dose of 54 degrees C for 1 minute. Clinical, gross, and histopathological evaluations were performed. RESULTS: Clinical evaluations of the treatment sites (immediately after microwave application) revealed no evidence of conjunctival or scleral damage. Trace fluorescein 2% uptake was noted within the targeted zones. The first eye was sectioned along the equatorial axis. Examination of the ciliary body and pars plana revealed whitening of the ciliary processes and depigmentation. Histopathological evaluations revealed ciliary epithelial necrosis with pigment dispersion. The vascularity of the ciliary processes showed focal disruption and haemorrhage. The underlying ciliary muscle and sclera appeared to be unaffected. No other findings could be attributed to microwave cyclodestruction. CONCLUSION: The results of this phase I toxicity study suggest that microwave heating can be used to damage preferentially the epithelial layers of the human ciliary body.

Aged↗
PubMed1994

Palladium 103 plaque radiotherapy for uveal melanoma. Clinical experience.

PURPOSE: To evaluate the effect of palladium 103(103Pd) ophthalmic plaque brachytherapy on patients with uveal melanoma. BACKGROUND: Radioactive 103Pd seeds have become available for plaque brachytherapy, and computer-aided simulations have compared the intraocular dose distribution of 103Pd versus iodine 125 (125I) plaques in patients with uveal melanoma. The use of the lower-energy radionuclide 103Pd increased the radiation to the tumors and decreases irradiation of most normal ocular structures. METHODS: The authors have begun a phase 1 clinical trial evaluating the effect of 103Pd ophthalmic plaque radiotherapy on intraocular tumors. Uveal melanoma was diagnosed, and the patients were found to be negative for metastatic disease. All patients were given one 103Pd radioactive plaque treatment, and six patients also were given adjuvant microwave hyperthermia. RESULTS: Palladium 103 ophthalmic plaque radiotherapy was used to treat 23 patients with uveal melanoma. Patients were followed for up to 27 months (mean, 13.5 months). One eye was enucleated for progressive tumor enlargement (4 months after treatment). One patient died (of metastatic melanoma). Eight patients have lost greater than two lines of visual acuity, one has gained more than two lines. Fifteen patients (65%) were within two lines or had better than their preoperative visual acuity. Relating to the effect of treatment on visual acuity, 15 (65%) tumors were located equal to or less than 2 mm from the fovea. CONCLUSION: Palladium 103 ophthalmic plaque radiotherapy was noted to control the growth of uveal melanomas. Compared with other forms of plaque radiotherapy at this follow-up interval, the authors have noted no new complications, no difference in local control, and/or changes in tumor response to treatment. More long-term follow-up will be required to demonstrate differences between 125I and 103Pd ophthalmic plaque brachytherapy.

Brachytherapy↗
PubMed1993

Palladium-103 versus iodine-125 for ophthalmic plaque radiotherapy.

PURPOSE: A dosimetry study comparing the use of I-125 vs. Pd-103 radioactive seeds for ophthalmic plaque brachytherapy. METHODS AND MATERIALS: Palladium-103 (Pd-103) seeds in ophthalmic plaques were used to treat 15 patients with intraocular malignant melanoma. Computer-aided simulations were performed to evaluate the intraocular dose distribution of I-125 versus Pd-103 ophthalmic plaques (delivering equivalent apex doses). Seven target points were selected. Starting at the outer scleral surface, four were located along the central axis of the plaque: the 1 mm point (the inner sclera), the 6 mm point, the tumors apex, and the opposite eye wall. We also evaluated the fovea, optic nerve, and the lens because they were considered to be critical structures. RESULTS: These studies demonstrated that the lower energy photons generated by Pd-103 seeds (average 21 KeV) in ophthalmic plaques were more rapidly absorbed in tissue than photons generated by I-125 (average 28 KeV). Therefore, during ophthalmic plaque radiotherapy, Pd-103 photons were found to be more rapidly absorbed within the tumor and less likely to reach most normal ocular structures. On average, the use of Pd-103 decreased the dose to the fovea by 5.7%, to the optic nerve by 8.4%, to the lens by 26%, and to the opposite eye wall by 38.4%. CONCLUSION: Palladium-103 ophthalmic plaque brachytherapy resulted in slightly more irradiation of the tumor and less radiation to most normal ocular structures.

Brachytherapy↗
PubMed1993

Microwave diathermy of the retina and choroid.

Microwaves were used to induce chorioretinal scar formation in normal rabbit eyes. We have developed a directional 6.8-gigahertz microwave applicator with a rectangular aperture. It was designed to mimic the shape and function of a T-shaped scleral depressor. For treatment, the applicator was placed on the conjunctiva over the sclera. Then, indentation was used to visualize probe placement during indirect ophthalmoscopy. Thermocouple-controlled heating was initiated such that conjunctival temperatures in a range of 51 degrees C to 65 degrees C were induced for 10 seconds per treatment. We found that treatment at temperatures of 51 degrees C or 52 degrees C for 10 seconds produced circular areas of acute retinal whitening. From these microwave-induced lesions, there evolved chorioretinal attenuation with and without evidence of retinal pigment epithelial hyperplasia. No evidence of scleral damage was noted at these thermal doses.

Animals↗