Introduction: The purpose of this study was to develop a statistical model for prediction of radiation induced sensorineural hearing loss (SNHL) induced by radiotherapy in patients with brain tumors.   Materials and Methods: CT scan of 18 patients (10 males and 8 females) with brain tumor who were referred to Radiation Center of Milad Hospital in Isfahan in 2...

  Primary Hepatic Lymphoma (PHL) is rare and possibly associated with viral hepatitis and autoimmune diseases. Scleroderma could exceptionally be complicated by lymphoma. We describe PHL occurring in a 52-year-old female suffering scleroderma for eight years, with no history of cytotoxic or high-dose glucocorticoid therapy. CT scan, performed to work-up abdominal discomfort, constipation, and ...

The purpose of this study was to evaluate the dosimetric uncertainty in 4D dose calculation using three temporal probability distributions: uniform distribution, sinusoidal distribution, and patient-specific distribution derived from the patient respiratory trace. Temporal probability, defined as the fraction of time a patient spends in each respiratory amplitude, was evaluated in nine lung can...

The purpose of this study is to evaluate the dosimetric accuracy of MRI-based treatment planning for prostate cancer using a commercial radiotherapy treatment planning system. Three-dimensional conformal plans for 15 prostate patients were generated using the AcQPlan system. For each patient, dose distributions were calculated using patient CT data with and without heterogeneity correction, and...

In x-ray computed tomography (CT), the most common parameter used to estimate and minimize patient dose is the CT dose index (CTDI). The CTDI is a volume-averaged measure that is used in situations where the table is incremented in conjunction with the tube rotation. Variants of the CTDI correct for averaging across the field of view and for adjacent beam overlaps or gaps. CTDI is usually measu...

Radiation dose in x-ray computed tomography (CT) has become a topic of high interest due to the increasing numbers of CT examinations performed worldwide. This review aims to present an overview of current concepts for both scanner output metrics and for patient dosimetry and will comment on their strengths and weaknesses. Controversial issues such as the appropriateness of the CT dose index (C...