Assessment of bladder motion for clinical radiotherapy practice using cine-magnetic resonance imaging.

PURPOSE: Organ motion is recognized as the principal source of inaccuracy in bladder radiotherapy (RT), but there is currently little information on intrafraction bladder motion. METHODS AND MATERIALS: We used cine-magnetic resonance imaging (cine-MRI) to study bladder motion relevant to intrafraction RT delivery. On two occasions, a 28 minute cine-MRI sequence was acquired from 10 bladder cancer patients and 5 control participants immediately after bladder emptying, after abstinence from drinking for the preceding hour. From the resulting cine sequences, bladder motion was subjectively assessed. To quantify bladder motion, the bladder was contoured in imaging volume sets at 0, 14, and 28 min to measure changes to bladder volumes, wall displacements, and center of gravity (COG) over time. RESULTS: The dominant source of bladder motion during imaging was bladder filling (up to 101% volume increase); rectal and small bowel movements were transient, with minimal impact. Bladder volume changes were similar for all participants. However for bladder cancer patients, wall displacements were larger (up to 58 mm), less symmetrical, and more variable compared with nondiseased control bladders. CONCLUSIONS: Significant and individualized intrafraction bladder wall displacements may occur during bladder RT delivery. This important source of inaccuracy should be incorporated into treatment planning and verification.

Trans-perineal implantation of radio-opaque treatment verification markers into the prostate: an assessment of procedure related morbidity, patient acceptability and accuracy.

On-line imaging of prostate markers can be used to compensate for errors in radiation delivery. This study assessed the patient acceptability and morbidity associated with the trans-perineal route of implantation. A minority experienced acute pain or bleeding. Placement was accurate in all but one subject. An operator related learning curve exists. Although this is an invasive procedure most patients found it acceptable. Implementation for routine clinical practice is feasible.

Evaluation of the LENT-SOMA scales for the prospective assessment of treatment morbidity in cervical carcinoma.

PURPOSE: To examine the Late Effects Normal Tissue Task Force (LENT)-Subjective, Objective, Management, Analytic (SOMA) scales prospectively in carcinoma of the cervix treated curatively with radiotherapy (RT) using interviews and postal questionnaires and to test the sensitivity of the scales in assessing the radiation effects. METHODS AND MATERIALS: A consecutive series of 100 patients completed questionnaires to score the subjective part of the published LENT-SOMA scales. Assessments were made before RT and at approximately 21, 70, 200, 400, 600, and 800 days after the start of treatment. The acceptability and feasibility of using the scales was examined using compliance in completion of the questionnaires. The scales were validated by evaluating the concordance of data obtained by two independent scorers and by examining the ability of the scales to measure radiation-related symptoms. RESULTS: Questionnaires were completed for 89 patients before RT. The level of noncompliance was 11%. The concordance between scores when two people completed the questionnaires independently was excellent. Subjective subsite scores were highest 21 days after treatment but generally fell by 70 days. The average baseline overall LENT-SOMA subjective scores increased with advancing stage (p = 0.008) and were higher for patients treated with RT alone (p = 0.044). CONCLUSION: In cervical carcinoma, the LENT-SOMA scales were acceptable and feasible to administer in the clinic and appropriate in the measurement of early subjective morbidity from RT.