Interfractional reproducibility of lung tumor location using various methods of respiratory motion mitigation.

Purpose: To determine interfractional reproducibility of the location of lung tumors using respiratory motion mitigation.

Methods And Materials: Free-breathing four-dimensional computed tomography (CT) data sets and CT data sets during breath hold were acquired weekly for 17 patients undergoing treatment for non-small-cell lung cancer. Distances between the center of the gross tumor volume (GTV) and a reproducible bony reference point under conditions of breath hold on end inspiration (EI) and end expiration (EE) and during free breathing on the 0% phase (corresponding to EI) and 50% phase (corresponding to EE) were analyzed for interfractional reproducibility.

Potential dosimetric benefits of four-dimensional radiation treatment planning.

Purpose: To determine the extent of dosimetric differences between conventional three-dimensional (3D) dose calculations and four-dimensional (4D) dose calculations based on deformation of organ models.

Methods And Materials: Four-dimensional dose calculations were retrospectively performed on computed tomography data sets for 15 patients with Stage III non-small-cell lung cancer, using a model-based deformable registration algorithm on a research version of a commercial radiation treatment planning system. Target volume coverage and doses to critical structures calculated using the 4D methodology were compared with those calculated using conventional 3D methodology.

Consequences of anatomic changes and respiratory motion on radiation dose distributions in conformal radiotherapy for locally advanced non-small-cell lung cancer.

Purpose: To determine the effect of interfractional changes in anatomy on the target and normal tissue dose distributions during course of radiotherapy in non-small-cell lung cancer patients.

Methods And Materials: Weekly respiration-correlated four-dimensional computed tomography scans were acquired for 10 patients. Original beam arrangements from conventional and inverse treatment plans were transferred into each of the weekly four-dimensional computed tomography data sets, and the dose distributions were recalculated.

Utility of four-dimensional computed tomography for analysis of intrafractional and interfractional variation in lung volumes.

Purpose: To assess the viability of four-dimensional (4D) computed tomography (CT) in describing intrafractional and interfractional changes in lung volumes and to determine which breathing phase, if any, produces the most highly reproducible lung volumes among fractions.

Methods And Materials: Weekly 4D CT scans were acquired for 13 patients with non-small-cell lung cancer during a course of radiotherapy. Contours delineating the right lung, left lung, and total lung were obtained by adapting library models of the anatomic structures to the CT images and propagating them to all 10 respiratory phases represented in the 4D CT image data set.

Determination of an optimal organ set to implement deformations to support four-dimensional dose calculations in radiation therapy planning.

Surface-based deformable image registration to generate a four-dimensional (4D) dose calculation in radiation treatment planning requires the selection of a set of organ contours to represent a basis set to generate anatomic deformation. The purpose of the present work was to determine the optimal set of organs needed to generate a basis set for deformation in treatment planning for thoracic tumors such that the required computations are minimized but dose accuracy is high. Using retrospectively reviewed records, we calculated 4D dose distributions based on treatment plans for 10 patients with thoracic tumors using a deformable model algorithm in a research version of a commercial radiation treatment planning system.

International Scientific Committee of Radionuclides in Nephrourology (ISCORN) consensus on renal transit time measurements.

This report is the conclusion of the international consensus committee on renal transit time (subcommittee of the International Scientific Committee of Radionuclides in Nephrourology) and provides recommendations on measurement, normal values, and analysis of clinical utility. Transit time is the time that a tracer remains within the kidney or within a part of the kidney (eg, parenchymal transit time). It can be obtained from a dynamic renogram and a vascular input acquired in standardized conditions by a deconvolution process.

A phase II study on stereotactic body radiotherapy for stage I non-small cell lung cancer.

Background And Purpose: The outcome of stage I non-small cell lung cancer (NSCLC) patients treated with conventional radiotherapy is inferior to that of patients treated surgically. We aimed to evaluate the clinical outcome of stereotactic body radiotherapy (SBRT) in the treatment of stage I NSCLC.

Materials And Methods: We performed SBRT for 31 stage I NSCLC patients.

Assessment of gross tumor volume regression and motion changes during radiotherapy for non-small-cell lung cancer as measured by four-dimensional computed tomography.

Purpose: To investigate the magnitudes of the changes in mobility and volume of locally advanced non-small-cell lung cancer (NSCLC) tumors during radiotherapy, using four-dimensional computed tomography (4DCT).

Methods And Materials: Five to ten 4DCT data sets were acquired weekly for each of 8 patients throughout treatment. Gross tumor volumes (GTVs) were outlined on each data set.

The management of differentiated thyroid cancer using 123I for imaging to assess the need for 131I therapy.

Background: Follow-up of 131I whole-body scanning after 131I ablation is associated with potential stunning. Previous studies have suggested that, for scanning, 123I is more sensitive than 131I in identifying thyroid tissue, but its specificity when positive is less certain.

Aim: The use of 123I as an imaging agent in place of serial 131I imaging has been evaluated in the surveillance and treatment of differentiated thyroid carcinoma.

The prospective clinical and scintigraphic assessment of patients with preserved left ventricular systolic function after transmyocardial laser revascularisation.

Aim: To analyse the clinical outcome and myocardial perfusion and function after transmyocardial revascularisation (TMR) in patients with normal left ventricular function and multivessel coronary artery disease non-amenable for standard revascularisation.

Method And Results: Twenty three severely symptomatic patients (CCS score median 4) with normal left ventricular systolic function but coronaries non-amenable for either PTCA or CABG were subjected to TMR. The angina score, left ventricular systolic and diastolic function in radionuclide ventriculography at rest, exercise tolerance and myocardial perfusion--Thallium-201 SPECT (adenosine stress 74 and 37 MBq under nitrate cover) were evaluated before and 3, 6, 12 months post-operatively.

Imaging with radiolabelled monoclonal antibody (MUJ591) to prostate-specific membrane antigen in staging of clinically localized prostatic carcinoma: comparison with clinical, surgical and histological staging.

Objective: To evaluate the reliability of prostate scintigraphy using a radiolabelled antibody (MUJ591) raised against the external domain of prostate-specific membrane antigen (PSMA) in the staging of early prostate cancer.

Patients And Methods: This was a prospective study of 16 patients who had radical retropubic prostatectomies (median PSA 9.75 ng/mL).

Evaluation of inter- and intrafraction organ motion during intensity modulated radiation therapy (IMRT) for localized prostate cancer measured by a newly developed on-board image-guided system.

Purpose: To investigate prostatic organ motion at both setup and intrafraction using an onboard image-guided system. An intrafraction field-based repositioning method also was evaluated.

Materials And Methods: A dual fluoroscopy with amorphous-silicon flat panel (DFFP) system was used for the three-dimensional registration of implanted markers in the prostate of eight organ-confined cancer patients planned for treatment with intensity modulated radiation therapy (IMRT).

Elimination of the influence of total renal function on renal output efficiency and normalized residual activity.

Unlabelled: One of the potential limitations in the usefulness of both renal output efficiency (ROE) and normalized residual activity (NORA) is their residual dependence on total renal function. The purpose of this study was to present and examine a new quantitative method whereby the effects of this dependence may be removed.

Methods: The analytic method involves the determination of a retention function using an unconstrained matrix algorithm deconvolution technique followed by reconvolution with a chosen standard input function to yield a new secondary renal activity time (A/T) curve from which normalized values of ROE and NORA, denoted as N_ROE and N_NORA, respectively, can then be obtained using conventional definitions.

[Clinical outcome of patients after transmyocardial laser revascularization alone and combined with coronary artery bypass grafting].

The aim of the study was to assess the effect of transmyocardial laser revascularization (TMLR) alone and in combination with coronary artery bypass grafting (CABG) on the angina score (CCS--Canadian Cardiovascular Society class), exercise tolerance and left ventricular function 6 months after the procedures. Sixty two patients were subjected to revascularization, 38 to sole TMLR procedure and 24 to combination CABG and TMLR (CABG/TMLR group). The angina score and exercise stress test together with radionuclide ventriculography were performed before and 6 months after the operation.

The comparison of two gated SPET protocols: adenosine Tc-99m tetrofosmin and treadmill exercise Tc-99m MIBI.

Background: The effect of adenosine and exercise on gated SPET left ventricular ejection fraction (LVEF), end diastolic volume (EDV) and end systolic volume (ESV) has not been fully investigated. The aim of the study was to compare functional measurements obtained in one-day adenosine rest and two-day stress-rest protocols in relation to ischaemia.

Material And Methods: Out of 226 consecutive patients examined with submaximal treadmill stress-rest 700 MBq Tc-99m MIBI, 26 were chosen to match those subjected to adenosine (140 micro g/kg/min) enhanced by a low level exercise protocol (300 MBq and 700 MBq Tc-99m tetrofosmin for stress and rest respectively).

Left ventricular function assessed by gated spet after an exercise-augmented adenosine infusion. Correlation with myocardial ischaemia.

Background: Gated single photon emission tomography (SPET) may simultaneously assess perfusion and function of the myocardium.

Aim: To evaluate the relationship between the presence of ischaemia during an adenosine stress test and the changes in left ventricular (LV) function obtained after stress and at rest with gated SPET by using adenosine same-day stress and rest protocol.

Methods: The study population consisted of twenty eight patients.

Radiation therapy combined with cis-diammine-glycolatoplatinum (Nedaplatin) and 5-fluorouracil for untreated and recurrent esophageal cancer.

From January 1999 to November 2000, a total of 24 esophageal cancer patients (17 untreated and 7 recurrent cases) were treated with radiation therapy (60-70 Gy) combined with cis-diammine-glycolatoplatinum (Nedaplatin) (80-120 mg/body) and 5-fluorouracil (5-FU) (500-1,000 mg/body/24 h, continuous infusion for 5 days). Grade III leukocytopenia was observed in 6 (25%) of the patients. Grade III and IV thrombocytopenia was observed in one patient each.