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J Van Dyke

Publications and source records attributed to J Van Dyke.

8 recordsLinked to original sources

American Association of Physicists in Medicine Radiation Therapy Committee Task Group 53: quality assurance for clinical radiotherapy treatment planning.

In recent years, the sophistication and complexity of clinical treatment planning and treatment planning systems has increased significantly, particularly including three-dimensional (3D) treatment planning systems, and the use of conformal treatment planning and delivery techniques. This has led to the need for a comprehensive set of quality assurance (QA) guidelines that can be applied to clinical treatment planning. This document is the report of Task Group 53 of the Radiation Therapy Committee of the American Association of Physicists in Medicine. The purpose of this report is to guide and assist the clinical medical physicist in developing and implementing a comprehensive but viable program of quality assurance for modern radiotherapy treatment planning. The scope of the QA needs for treatment planning is quite broad, encompassing image-based definition of patient anatomy, 3D beam descriptions for complex beams including multileaf collimator apertures, 3D dose calculation algorithms, and complex plan evaluation tools including dose volume histograms. The Task Group recommends an organizational framework for the task of creating a QA program which is individualized to the needs of each institution and addresses the issues of acceptance testing, commissioning the planning system and planning process, routine quality assurance, and ongoing QA of the planning process. This report, while not prescribing specific QA tests, provides the framework and guidance to allow radiation oncology physicists to design comprehensive and practical treatment planning QA programs for their clinics.

Algorithms↗

Improved oxygenation and lower peak airway pressure in severe adult respiratory distress syndrome. Treatment with inverse ratio ventilation.

Two patients with the adult respiratory distress syndrome (ARDS) were placed on pressure-controlled inverse-ratio ventilation (IRV) when their condition deteriorated despite optimal treatment with intermittent mandatory ventilation and positive end-expiratory pressure. In the first case, high peak airway pressure was reduced by 50 percent with the institution of IRV. In the second, refractory hypoxemia was eliminated by using an inspiratory-to-expiratory ratio of 4:1. These cases show that IRV may offer certain advantages in the treatment of severe ARDS.

Adult↗

Computed tomography in malignant endometrial neoplasms.

Malignant uterine neoplasms are the most common invasive gynecological malignancies. The prognosis depends on the history, the grade, and the stage. Recent reports have stressed that a small percentage of patients with clinically low stage disease have unsuspected metastases. We retrospectively reviewed 61 patients with known malignant uterine neoplasms. In 18 patients with preoperative computed tomographic examinations, these scans detected unsuspected omental metastases in two and pelvic adenopathy in three. There was one false positive and one false negative examination. Computed tomography was superior to the clinical examination in defining the extent of the tumor in five patients. Computed tomography was also helpful in evaluating patients with suspected recurrent disease.

Adenocarcinoma↗