Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Wallace A. Longton is active.

Publication


Featured researches published by Wallace A. Longton.


International Journal of Radiation Oncology Biology Physics | 1996

External Radiotherapy in Macular Degeneration: Technique and Preliminary Subjective Response

Jorge E. Freire; Wallace A. Longton; Curtis T. Miyamoto; Luther W. Brady; James J. Augsburger; Gary C. Brown; Bizhan Micaily; Ricardo Unda

PURPOSE This study attempted to assess the toxicity and possible preliminary benefits from the administration of low-dose external beam irradiation for age-related macular degeneration (ARMD). The premise of the treatment is that radiation induces regression and/or promotes inactivation of the subretinal neovasculature which would result in reabsorption of fluid and blood. This would reduce the risk for further leakage or bleeding, as well as subretinal fibrosis. Consequently, the beneficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet ARMD with the possibility for slight improvement. METHODS AND MATERIALS Allegheny University Department of Radiation Oncology treated 41 patients prospectively from January through October 1995 with low-dose irradiation for wet-type macular degeneration. A total of 39 patients were treated with a total dose of 14.4 Gy in eight fractions of 1.8 Gy/fraction over 10-13 elapsed days. The first two patients were treated with a total dose of 10 Gy in five fractions of 2 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. Some of the patients (36.7%) had laser treatments in the study eye: 21.9% (9) once, 5% (2) twice, 9.7% (4) thrice or more. Subjective visual acuity and toxicity data were collected on all patients. RESULTS At 2-3 weeks after treatment 29 patients (70%) retained their visual acuity without change, 10 (24.5%) stated they had improved vision, and 2 (4.8%) stated their vision continued to decrease. At 2-3 months after treatment, 27 patients (65.8%) had no change in their vision, 11 (27%) had an improvement in their vision, and 3 (7.2%) had a decrease in visual acuity. Six patients of 41 in the treated group had acute transient side effects. CONCLUSION Our observations in this group of 41 patients support the conclusion that many patients will have improved or stable vision after treatment with low-dose irradiation for age-related wet-type macular degeneration.


International Journal of Radiation Oncology Biology Physics | 1997

Radiation therapy for macular degeneration: technical considerations and preliminary results.

Luther W. Brady; Jorge E. Freire; Wallace A. Longton; Curtis T. Miyamoto; T James J. Augsburger; Gary C. Brown; Bizhan Micaily; Robert H. Sagerman

Purpose: This study was undertaken to assess the toxicity and possible benefits from the administration of low-dose external-beam irradiation for Age-Related Macular Degeneration (ARMD). The premise of the treatment is that radiation induces regression and/or promotes inactivation of the subretinal neo-vasculature, resulting in reabsorption of fluid and blood thus reducing the risk for further leakage or bleeding, as well as subretinal fibrosis. Clinically, the beneficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet type of ARMD with the possibility for some visual improvement. Methods and Materials: Allegheny University Hospitals, Hahnemann, Department of Radiation Oncology, treated 278 patients prospectively beginning in January 1995 with low-dose irradiation for wet-type macular degeneration. Two hundred forty-nine patients were treated with a total dose of 14.40 Gy in eight fractions of 1.80 Gy over 10-13 elapsed days, and 27 patients with 20 Gy at 2 Gy per fraction over 12-15 days. The first two patients were treated to a total dose of 10.00 Gy in five fractions of 2.00 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. A percentage (36.7%) of the patients had previously received laser treatments in the study eye, 21.9% once, 5% twice, 9.7% three or more. Subjective visual acuity and toxicity data was collected on all patients. Results: At 2-3 weeks after treatment 195 patients (70%) retained their visual acuity without change, 68 patients (24.5%) stated they had improved vision, and 15 patients (4.8%) stated their vision continued to decrease. Two to 3 months after treatment, 183 patients (65.8%) had no change in their vision. 75 patients (27%) patients had an improvement in their vision, and 20 patients (7.2%) had a decrease in visual acuity. Transient acute reactions occurred in 14 of the 278 patients treated. Conclusion: Our observations in this group of 278 patients support the conclusion that many patients will have improved or stable vision after treatment with low-dose irradiation for age related wet type macular degeneration.


Seminars in Surgical Oncology | 1997

Brachytherapy in primary ocular tumors.

Jorge E. Freire; Patrick De Potter; Luther W. Brady; Wallace A. Longton

Patients with primary ocular tumors are seen infrequently in the medical profession, and most of these patients are referred to specialty centers which has resulted in a good study population. In the past, ocular tumors were treated with enucleation, but the current emphasis is now on organ preservation with sparing of all or partial visual acuity. In the management of these tumors, plaque brachytherapy and particle beam therapy have been used more frequently as an alternative to enucleation. A multi-institutional study, the Collaborative Ocular Melanoma Study (COMS), is currently underway, organized by the National Eye Institute. The COMS isotope of choice is Iodine-125 (I-125). Recurrence after plaque therapy is approximately 15%, although it may be as high as 37% at 15 years for metastatic disease. In one study, nondiffuse iris melanoma has been controlled in 93% of patients by custom plaques utilizing I-125. Plaque brachytherapy also utilizes I-125 for the treatment of retinoblastoma tumors either as primary therapy or following external beam radiation. Currently, through the utilization of plaque radiation therapy, enucleation may be avoided in the majority of patients, and many patients may retrieve some visual acuity. We will review plaque brachytherapy techniques, diagnosis, staging, and some of the pertinent literature of the two most frequently encountered primary ocular tumors: choroidal melanoma, sometimes referred to as uveal melanoma, with an incidence of approximately 1,500 new cases per year in the adult population; and retinoblastoma, the most common intraocular primary malignancy found in childhood, with a frequency of approximately 250 [corrected] new cases per year.


Archive | 1998

Treatment-Related Complications for Bladder Carcinoma: Radical Surgery Versus Bladder-Preserving Techniques

B. J. Costleigh; Wallace A. Longton; Luther W. Brady; Curtis T. Miyamoto; J. E. Friere; Bizhan Micaily; F. Farzin

The morbidity and mortality of bladder carcinoma treatment are dependent upon which treatment modalities are employed. The treatment should be chosen to best fit the stage of disease. The standard treatment regimen for in situ or early-stage bladder cancer has been transurethral resection of the bladder tumor (TURBT). This treatment is given with or without intravesicular chemotherapy or BCG therapy for many years and is very tolerable with regard to morbidity of normal tissues.


Seminars in Surgical Oncology | 1997

Freire JE, De Potter P, Brady LW, Longton WA: Brachytherapy in primary ocular tumors. Semin Surg Oncol 1997; 13:167‐176.

Jorge E. Freire; P DePotter; Luther W. Brady; Wallace A. Longton

There is an error at the end of this abstract. It reads: “approximately 15,000 new cases per year”. It should read: “one in every 15,000 live births, 250 cases a year”. The corrected abstract is printed below. Patients with primary ocular tumors are seen infrequently in the medical profession, and most of these patients are referred to specialty centers which has resulted in a good study population. In the past, ocular tumors were treated with enucleation, but the current emphasis is now on organ preservation with sparing of all or partial visual acuity. In the management of these tumors, plaque brachytherapy and particle beam therapy have been used more frequently as an alternative to enucleation. A multi-institutional study, the Collaborative Ocular Melanoma Study (COMS), is currently underway, organized by the National Eye Institute. The COMS isotope of choice is Iodine-125 (I-125). Recurrence after plaque therapy is approximately 15%, although it may be as high as 37% at 15 years for metastatic disease. In one study, nondiffuse iris melanoma has been controlled in 93% of patients by custom plaques utilizing I-125. Plaque brachytherapy also utilizes I-125 for the treatment of retinoblastoma tumors either as primary therapy or following external beam radiation. Currently, through the utilization of plaque radiation therapy, enucleation may be avoided in the majority of patients, and many patients may retrieve some visual acuity. We will review plaque brachytherapy techniques, diagnosis, staging, and some of the pertinent literature of the two most frequently encountered primary ocular tumors: choroidal melanoma, sometimes referred to as uveal melanoma, with an incidence of approximately 1,500 new cases per year in the adult population; and retinoblastoma, the most common intraocular primary malignancy found in childhood, with a frequency of approximately one in every 15,000 live births, 250 cases a year. Semin. Surg. Oncol. 13:167-176, 1997.


Archive | 1999

Graduated intraluminal catheter and methods of use thereof

Wallace A. Longton; Curtis Miyamoto; Daniel Rukstalis


Archive | 2002

Diagnostic imaging tabletop

Wallace A. Longton; Curtis Miyamoto


Cancer Journal | 2002

Tc-99m Sulfur Colloid Imaging in Evaluation of Adhesion Formation Post External Beam Radiation Therapy or P-32 Therapy: P-39

Simin Dadparvar; Wallace A. Longton; Curtis Miyamoto; Christopher M. Hand; Jacqueline Emrich; Gustavo Ayala


Archive | 1999

Intraluminal catheter with a scale, as well as methods for its application

Wallace A. Longton; Curtis Miyamoto; Daniel Rukstalis


Archive | 1999

Intraluminaler katheter mit einer skala, sowie methoden zu seiner anwendung The intraluminal catheter having a scale, as well as methods for its application

Wallace A. Longton; Curtis Miyamoto; Daniel Rukstalis

Collaboration


Dive into the Wallace A. Longton's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge