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At least 379 records · Page 21Linked to original sources
PubMed1999

T2-weighted breathold imaging of the liver: a quantitative and qualitative comparison of fast spin echo and half Fourier single shot fast spin echo imaging.

The imaging characteristics of two EPI-hybrid breath-hold sequences, T2-weighted fast spin-echo [FSE, effective echo time (TEeff) 138 ms] and half Fourier single shot turbo spin-echo (HASTE, TEeff 60 ms), were compared in hepatic imaging. A total of 111 patients with suspected hepatic disease were studied at 1.5 Tesla using a body phase-array coil. The signal-to-noise (S/N) and contrast-to-noise (C/N) ratios for organs and lesions were calculated and quantitatively compared. Organ delineation, visualization of anatomical structures and pathological lesions, artifacts, and total image quality were qualitatively assessed and statistically compared. The final diagnoses were metastases from colorectal, breast, and pancreatic cancer in 23/111, hepatocellular carcinoma in 15/111, cysts in 19/111, hemangiomas in 9/111, several other lesions in 7/111, and no lesions in 38/111 of the cases. A total of 139 lesion in 73% of the patients were seen while 85% of the lesions were at least 1.5 cm in size. Regarding S/Ns HASTE was significantly (P < 0.03) superior to FSE with only minor (P > 0.05) differences in C/Ns between the two sequences for anatomical and pathological structures. HASTE demonstrated in almost all (97.3%) of the cases no artifacts, while on fast SE imaging moderate to minor artifacts were present in 23.5-51.7% of the cases. The overall image quality and diagnostic confidence was rated significantly higher (good 43.2%, excellent 53.2%) for HASTE than for fast SE imaging (good 44.8%, excellent 17.6%). Providing comparable C/Ns for anatomical and pathological structures, breatheld HASTE imaging proved to be superior to fast SE in T2-weighted imaging of the upper abdomen regarding general image quality, and, with adequate technical prerequisites, may be a suitable substitute of fast T2-imaging techniques.

Evaluation Studies as Topic↗
PubMed1997

A digital imaging and communications in medicine (DICOM) print service for chest imaging.

Large-scale picture archiving and communication systems (PACS) have not been widely implemented in this or other countries. In almost all radiology departments film remains the medium for diagnostic interpretation and image archive. Chest imaging is the dominant screening examination performed within most imaging departments and as such, is an extremely high-volume, low-margin examination. Digital technologies are being applied to chest imaging to overcome limitations of screen-film receptors (limited latitude) and current film management systems (single-image copy). Efficient management of images and information is essential to the success of a chest imaging program. In this article we report on a digital imaging and communications in medicine (DICOM)-based centralized printing network for chest imaging. The system components and their operational characteristics are described. Our experience integrating DICOM-compliant equipment supplied by several vendors is described. We conclude that the print model supported by DICOM is adequate for cross-sectional (eg, computed tomography and magnetic resonance) imaging but is too simplistic to be generally applied to projection radiography.

Humans↗
PubMed1997

High-resolution echo-planar imaging of the brain: is it suitable for routine clinical imaging?

To assess the value of echo-planar imaging (EPI) for ultra-fast routine clinical diagnostic MRI, we compared four different EPI sequences with conventional T2-weighted spin-echo images on a commercial clinical imager. We examined 25 randomly selected patients who posed different clinical questions. The images were interpreted by two experienced neuroradiologists blinded as to the sequence used. Image quality and diagnostic certainty were evaluated and the main diagnosis established from the EPI study was compared to that obtained from the T2-weighted images. Finally, EPI- and T2-based diagnoses were compared with the diagnosis resulting from a complete MRI examination. Apart from one sequence that was generally rated low as regards both diagnostic certainty and image quality, the EPI sequences were comparable to each other, but inferior to the T2-weighted images. However, two EPI sequences gave better diagnostic results than T2-weighted images compared to the full MRI examination. Gradient-echo EPI was particularly sensitive to haemorrhagic lesions. All normal cases were correctly identified on EPI studies. Only two pathological cases were missed; both had isolated cranial nerve lesions. The absence of false-positive results and the high sensitivity to ischaemic and mass lesions mean that EPI can be used for ultra-fast screening. However, from these initial studies, EPI seems unsuitable for neuroradiological investigation of patients who may have subtle lesions whose detection requires either special sequences or administration of contrast medium. EPI can nevertheless be used in addition to high-resolution T1-weighted images and may replace T2-weighted spin-echo sequences for special indications.

Adolescent↗
PubMed2004

Interactive image enhancement of CR and DR images.

There is continual pressure on the radiology department to increase its productivity. Two important links to productivity in the computed/digital radiography (CR/DR) workflow chain are the postprocessing step by technologists and the primary diagnosis step by radiologists, who may apply additional image enhancements to aid them in diagnosis. With the large matrix size of CR and DR images and the computational complexity of these algorithms, it has been challenging to provide interactive image enhancement, particularly on full-resolution images. We have used a new programmable processor as the main computing engine of enhancement algorithms for CR or DR images. We have mapped these algorithms to the processor, maximally utilizing its architecture. On a 12-bit 2688 x 2688 image, we have achieved the execution time of 465A ms for adaptive unsharp masking, window/level, image rotate, and lookup table operations using a single processor, which represents at least an order of magnitude improvement compared to the response time of current systems. This kind of performance facilitates rapid computation with preset parameter values and/or enables truly interactive QA processing on radiographs by technologists. The fast response time of these algorithms would be especially useful in a real-time radiology setting, where the radiologist's waiting time in performing image enhancements before making diagnosis can be greatly reduced. We believe that the use of these processors for fast CR/DR image computing coupled with the seamless flow of images and patient data will enable the radiology department to achieve higher productivity.

Algorithms↗
PubMed2004

Validation of diagnostic imaging based on repeat examinations. An image interpretation model.

PURPOSE: To develop an interpretation model, based on repeatedly acquired images, aimed at improving assessments of technical efficacy and diagnostic accuracy in the detection of small lesions. MATERIAL AND METHODS: A theoretical model is proposed. The studied population consists of subjects that develop focal lesions which increase in size in organs of interest during the study period. The imaging modality produces images that can be re-interpreted with high precision, e.g. conventional radiography, computed tomography, and magnetic resonance imaging. At least four repeat examinations are carried out. RESULTS: The interpretation is performed in four or five steps: 1. Independent readers interpret the examinations chronologically without access to previous or subsequent films. 2. Lesions found on images at the last examination are included in the analysis, with interpretation in consensus. 3. By concurrent back-reading in consensus, the lesions are identified on previous images until they are so small that even in retrospect they are undetectable. The earliest examination at which included lesions appear is recorded, and the lesions are verified by their growth (imaging reference standard). Lesion size and other characteristics may be recorded. 4. Records made at step 1 are corrected to those of steps 2 and 3. False positives are recorded. 5. (Optional) Lesion type is confirmed by another diagnostic test. CONCLUSION: Applied on subjects with progressive disease, the proposed image interpretation model may improve assessments of technical efficacy and diagnostic accuracy in the detection of small focal lesions. The model may provide an accurate imaging reference standard as well as repeated detection rates and false-positive rates for tested imaging modalities. However, potential review bias necessitates a strict protocol.

Diagnostic Imaging↗
PubMed2002

Evaluation of image quality in terahertz pulsed imaging using test objects.

As with other imaging modalities, the performance of terahertz (THz) imaging systems is limited by factors of spatial resolution, contrast and noise. The purpose of this paper is to introduce test objects and image analysis methods to evaluate and compare THz image quality in a quantitative and objective way, so that alternative terahertz imaging system configurations and acquisition techniques can be compared, and the range of image parameters can be assessed. Two test objects were designed and manufactured, one to determine the modulation transfer functions (MTF) and the other to derive image signal to noise ratio (SNR) at a range of contrasts. As expected the higher THz frequencies had larger MTFs, and better spatial resolution as determined by the spatial frequency at which the MTF dropped below the 20% threshold. Image SNR was compared for time domain and frequency domain image parameters and time delay based images consistently demonstrated higher SNR than intensity based parameters such as relative transmittance because the latter are more strongly affected by the sources of noise in the THz system such as laser fluctuations and detector shot noise.

Diagnostic Imaging↗
PubMed2004

Improved image contrast of calcifications in breast tissue specimens using diffraction enhanced imaging.

The contrast of calcifications in images of breast tissue specimens using a synchrotron-based diffraction enhanced imaging (DEI) apparatus has been measured and is compared to the contrast in images acquired using a conventional synchrotron-based radiographic imaging modality. DEI is an imaging modality which derives image contrast from x-ray absorption, refraction and small-angle scatter-rejection (extinction), unlike conventional radiographic techniques, which can only derive contrast from absorption. DEI is accomplished by inserting an analyser crystal in the beam path between the sample and the detector. Two of the three breast tissue specimens contained calcifications associated with cancer, while a third contained benign calcifications. Results of the image analysis indicate that the DEI contrast of images taken with the analyser crystal tuned to the peak of its rocking curve, was as much as 19 times that of the conventional radiograph, with an average of 5.5 for all calcifications. This improved image contrast for even near-pixel-size calcifications suggests potential utility for DEI in breast imaging.

Breast Diseases↗
PubMed2006

A method of image registration for small animal, multi-modality imaging.

Many research institutions have a full suite of preclinical tomographic scanners to answer biomedical questions in vivo. Routine multi-modality imaging requires robust registration of images generated by various tomographs. We have implemented a hardware registration method for preclinical imaging that is similar to that used in the combined positron emission tomography (PET)/computed tomography (CT) scanners in the clinic. We designed an imaging chamber which can be rigidly and reproducibly mounted on separate microPET and microCT scanners. We have also designed a three-dimensional grid phantom with 1288 lines that is used to generate the spatial transformation matrix from software registration using a 15-parameter perspective model. The imaging chamber works in combination with the registration phantom synergistically to achieve the image registration goal. We verified that the average registration error between two imaging modalities is 0.335 mm using an in vivo mouse bone scan. This paper also estimates the impact of image misalignment on PET quantitation using attenuation corrections generated from misregistered images. Our technique is expected to produce PET quantitation errors of less than 5%. The methods presented are robust and appropriate for routine use in high throughput animal imaging facilities.

Animals↗
PubMed2002

Quantitative 3-d diagnostic ultrasound imaging using a modified transducer array and an automated image tracking technique.

An approach for acquiring dimensionally accurate three-dimensional (3-D) ultrasound data from multiple 2-D image planes is presented. This is based on the use of a modified linear-phased array comprising a central imaging array that acquires multiple, essentially parallel, 2-D slices as the transducer is translated over the tissue of interest. Small, perpendicularly oriented, tracking arrays are integrally mounted on each end of the imaging transducer. As the transducer is translated in an elevational direction with respect to the central imaging array, the images obtained by the tracking arrays remain largely coplanar. The motion between successive tracking images is determined using a minimum sum of absolute difference (MSAD) image matching technique with subpixel matching resolution. An initial phantom scanning-based test of a prototype 8 MHz array indicates that linear dimensional accuracy of 4.6% (2 sigma) is achievable. This result compares favorably with those obtained using an assumed average velocity [31.5% (2 sigma) accuracy] and using an approach based on measuring image-to-image decorrelation [8.4% (2 sigma) accuracy]. The prototype array and imaging system were also tested in a clinical environment, and early results suggest that the approach has the potential to enable a low cost, rapid, screening method for detecting carotid artery stenosis. The average time for performing a screening test for carotid stenosis was reduced from an average of 45 minutes using 2-D duplex Doppler to 12 minutes using the new 3-D scanning approach.

Carotid Arteries↗
PubMed1995

Digital portal image registration by sequential anatomical matchpoint and image correlations for real-time continuous field alignment verification.

Detection of radiotherapy field misalignments with electronic portal imaging devices requires the precise initial registration of the digital portal image with a reference image indicating the prescribed field alignment. Moreover, for real-time continuous detection this registration must be performed rapidly--arguably within 250 ms. The quality of this registration is sensitive to the ability of the user to accurately identify corresponding anatomical landmarks in the image pair. To improve the accuracy of the registration and, ultimately, that of the field misalignment measurement, we have developed a sequential digital portal image registration method using both user-identified anatomical matchpoints and image information. A first pass generates registration parameters from user-provided matchpoint coordinates and explicitly accounts for the uncertainty in matchpoint identification. The second pass uses both the initial registration parameters and image information to further improve the registration quality by maximizing cross correlations between segments of the image pair. As this registration method does not use massive matrix/vector computations common to other algorithms, it is inherently faster and well-suited for real-time field placement error detection. On a platform representative of those controlling many commercial electronic portal imaging devices (486 CPU), this algorithm registers portal images in times of less than 6 ms per matchpoint with errors of less than 2% in magnification, 0.5 degree in in-plane rotation, and less than 1 pixel dimension in in-plane translation. As the algorithm assumes a rigid-body geometry, it is sensitive to out-of-plane rotations. A quantitative analysis of this algorithm is presented, indicates its accuracy, and describes its sensitivity to out-of-plane rotations.

Algorithms↗
PubMed1998

Evaluation of imaging geometries calculated from biplane images.

A technique is developed that will calculate accurate and reliable imaging geometries and three-dimensional (3D) positions from biplane images of a calibration phantom. The calculated data provided by our technique will facilitate accurate 3D analysis in various clinical applications. Biplane images of a Lucite cube containing lead beads 1 mm in diameter were acquired. After identifying corresponding beads in both images and calculating their image positions, the 3D positions of the beads relative to each focal spot were determined. From these data, the transformation relating the 3D configurations were calculated to give the imaging geometry relating the biplane views. The 3D positions of objects were determined from the biplane images along with the corresponding imaging geometries. In addition, methods are developed to evaluate the quality of the calculated results on a case-by-case basis in the clinical setting. Methods are presented for evaluating the reproducibility of the calculated geometries and 3D positions, the accuracy of calculated object sizes, and the effects of errors due to time jitter, variation in user-indication, centering, and distortions on the calculated geometries and 3D reconstructions. The precision of the translation vectors and rotation matrices of the calculated geometries were within 1% and 1 degree, respectively, in phantom studies, with estimated accuracies of approximately 0.5% and 0.4 degree, respectively, in simulation studies. The precisions of the absolute 3D positions and orientations of the calculated 3D reconstructions were approximately 2 mm and 0.5 degree, respectively, in phantom studies, with estimated accuracies of approximately 1.5 mm and 0.4 degree, respectively, in simulation studies. This technique will provide accurate and precise imaging geometries as well as 3D positions from biplane images, thereby facilitating 3D analysis in various clinical applications. We believe that the study presented here is unique in that it represents the first steps toward understanding and evaluating the reliability of these 3D calculations in the clinical situation.

Biophysical Phenomena↗
PubMed2002

Water excitation as an alternative to fat saturation in MR imaging: preliminary results in musculoskeletal imaging.

PURPOSE: To compare fat suppression methods by using spectrally selective fat saturation and section-selective water excitation in standard magnetic resonance (MR) imaging sequences used in day-to-day musculoskeletal practice. MATERIALS AND METHODS: Eighty-three patients underwent MR examination with a 1.5-T system. The two methods were compared by using three common sequences: T1-weighted spin-echo (SE) imaging performed after contrast material injection (n = 24), intermediate-weighted fast SE (n = 36) imaging, and T2-weighted fast SE (n = 36) imaging. Acquisition times of the sequences and signal-to-noise and contrast-to-noise ratios of bone, muscle, fat, and water for the two methods were compared quantitatively. Images were then qualitatively reviewed by two radiologists who were blinded to the type of fat suppression used. Image quality was scored according to four criteria (homogeneity of fat suppression, susceptibility and foldover artifacts, conspicuousness of lesion, and overall image quality) by using a five-point scale (0, bad; 1, poor; 2, fair; 3, good; and 4, excellent). A paired Student t test was used to compare the quantitative data, and a nonparametric paired-data Wilcoxon signed rank test was used for qualitative analysis. RESULTS: Water excitation allowed a substantial decrease in acquisition time (by up to 50%) for T1-weighted sequences. Quantitative measurements revealed a greater signal-to-noise ratio (P <.01) with water excitation for all three sequences, whereas the contrast-to-noise ratio was greater with water excitation only in intermediate-weighted sequences (P <.01). Qualitatively, water excitation proved statistically better than or equal to fat saturation for all criteria in all imaging sequences (P <.05). Mean scores of overall image quality ranged between 2.5 and 3.0 for fat saturation and 3.4 and 3.7 for water excitation, respectively (P <.05). CONCLUSION: Section-selective water excitation is faster than conventional fat saturation and produces images of better quality.

Adolescent↗
PubMed1993

Wilms tumor and nephroblastomatosis: imaging characteristics at gadolinium-enhanced MR imaging.

Twelve children with Wilms tumors were prospectively evaluated with 1.5-T magnetic resonance (MR) imaging. Spin-echo images were obtained before and after administration of gadopentetate dimeglumine. Nine of the 12 children had histologically proved nephroblastomatosis or nephrogenic rests involving a total of 14 kidneys. MR imaging depicted involvement in eight of these kidneys, including five of five kidneys with lesions contralateral to the primary Wilms tumor. Overall sensitivity of detection of nephrogenic rests was 43% on nonenhanced images and 58% when gadolinium-enhanced images were added. Nephrogenic rests admixed with Wilms tumors less than 4 mm in diameter were not depicted at MR imaging. On gadolinium-enhanced T1-weighted images, Wilms tumors and hyperplastic were hypointense to normal renal tissue. On T2-weighted images, Wilms tumors and hyperplastic nephrogenic rests were iso- or slightly hyperintense to renal cortex, while sclerotic nephrogenic rests were hypointense to renal cortex. On all images, including gadolinium-enhanced T1-weighted images, the signal intensity of Wilms tumors was inhomogeneous, while the signal intensity of nephrogenic rests was homogeneous.

Child↗
PubMed1997

Peritoneal tumor: MR imaging with dilute oral barium and intravenous gadolinium-containing contrast agents compared with unenhanced MR imaging and CT.

PURPOSE: To compare fat-suppressed, gadolinium-enhanced, breath-hold magnetic resonance (MR) imaging after administration of dilute oral barium solution with unenhanced MR imaging and computed tomography (CT) in the detection of peritoneal tumors. MATERIALS AND METHODS: In 24 patients in whom peritoneal tumor was known or suspected, double-contrast MR imaging and CT were performed prospectively. MR imaging included T1-weighted, fast spin-echo T2-weighted, and immediate and delayed gadolinium-enhanced, breath-hold, fast multiplanar sequences with fat saturation. Helical and conventional dynamic CT were performed with intravenously and orally administered contrast media. MR images and CT scans were reviewed independently and prospectively by different pairs of radiologists for presence of peritoneal tumor in 17 anatomic sites. Imaging findings were compared with surgical and histopathologic results. RESULTS: Of the 24 patients, 18 had peritoneal tumor confirmed at surgery. Detection of tumor sites was superior with double-contrast MR images (mean sensitivity, specificity, and accuracy, 84%, 87%, and 86%, respectively) compared with CT scans (mean sensitivity, specificity, and accuracy, 54%, 91%, and 74%, respectively). Double-contrast MR imaging enabled better detection of carcinomatosis and tumors less than 1 cm in diameter (75%-80%) than CT (22%-33%; P < .0001). CONCLUSION: Double-contrast MR imaging demonstrated more peritoneal tumors than CT or unenhanced spin-echo MR imaging.

Administration, Oral↗
PubMed1999

Bedside imaging of intracranial hemorrhage in the neonate using light: comparison with ultrasound, computed tomography, and magnetic resonance imaging.

Medical optical imaging (MOI) uses light emitted into opaque tissues to determine the interior structure. Previous reports detailed a portable time-of-flight and absorbance system emitting pulses of near infrared light into tissues and measuring the emerging light. Using this system, optical images of phantoms, whole rats, and pathologic neonatal brain specimens have been tomographically reconstructed. We have now modified the existing instrumentation into a clinically relevant headband-based system to be used for optical imaging of structure in the neonatal brain at the bedside. Eight medical optical imaging studies in the neonatal intensive care unit were performed in a blinded clinical comparison of optical images with ultrasound, computed tomography, and magnetic resonance imaging. Optical images were interpreted as correct in six of eight cases, with one error attributed to the age of the clot, and one small clot not seen. In addition, one disagreement with ultrasound, not reported as an error, was found to be the result of a mislabeled ultrasound report rather than because of an inaccurate optical scan. Optical scan correlated well with computed tomography and magnetic resonance imaging findings in one patient. We conclude that light-based imaging using a portable time-of-flight system is feasible and represents an important new noninvasive diagnostic technique, with potential for continuous monitoring of critically ill neonates at risk for intraventricular hemorrhage or stroke. Further studies are now underway to further investigate the functional imaging capabilities of this new diagnostic tool.

Animals↗
PubMed1993

Perception of image quality in direct digital radiography after application of various image treatment filters for detectability of dental disease.

This study evaluated dentists' perception of the quality of digitally captured radiographs. Thirty radiographs were taken with the Visualix digital video radiographic system, 10 periapicals for tooth and bone anatomy, 10 periapicals for bone disease and 10 bitewings for dental caries. Three numeric copies were made of each image and treated with three different filters: 'optimize', 'enhance' and 'enhance + smooth', respectively. Four images of the same case were displayed simultaneously in a random sequence on the monitor. Twenty dentists ranked each set of four images on a scale from 1 to 4. In general, most dentists preferred a treated image to the original. The optimized and enhanced images were selected most frequently as first or second choice from the tooth and bone anatomy and bone disease groups. The original image was ranked lowest in more than half (55%) of the series. For the bitewings, the smoothed images were ranked significantly higher. In conclusion, image treatment possibilities should be offered in digital radiography as the majority of dentists preferred a treated image to the original version. The image treatment chosen seemed to be task dependent; less treatment was required to delineate the more subtle tissue differences.

Dental Caries↗
PubMed2001

A preliminary study on comparison and fusion of metabolic images of PET with anatomic images of CT and MRI.

OBJECTIVE: To compare and match metabolic images of PET with anatomic images of CT and MRI. METHODS: The CT or MRI images of the patients were obtained through a photo scanner, andthen transferred to the remote workstation of PET scanner with a floppy disk. A fusion method was developed to match the 2-dimensional CT or MRI slices with the correlative slices of 3-dimensional volume PET images. RESULTS: Twenty-nine metabolically changed foci were accurately localized in 21 epilepsy patients' MRI images, while MRI alone had only 6 true positive findings. In 53 cancer or suspicious cancer patients, 53 positive lesions detected by PET were compared and matched with the corresponding lesions in CT or MRI images, in which 10 lesions were missed. On the other hand, 23 lesions detected from the patients' CT or MRI images were negative or with low uptake in the PET images, and they were finally proved as benign. CONCLUSIONS: Comparing and matching metabolic images with anatomic images helped obtain a full understanding about the lesion and its peripheral structures. The fusion method was simple, practical and useful for localizing metabolically changed lesions.

Carcinoma, Squamous Cell↗
PubMed2005

The role of imaging with (111)In-ibritumomab tiuxetan in the ibritumomab tiuxetan (zevalin) regimen: results from a Zevalin Imaging Registry.

UNLABELLED: The ibritumomab tiuxetan therapeutic regimen consists of a dose of rituximab, 250 mg/m(2), followed by (111)In-ibritumomab tiuxetan, for imaging, on day 1 and a dose of rituximab followed by (90)Y-ibritumomab tiuxetan, for therapy, on day 7, 8, or 9. Treatment with the Food and Drug Administration-approved regimen also requires that scans be performed at 2-24 h and at 48-72 h after the (111)In-ibritumomab tiuxetan, with an optional third scan at 90-120 h, to confirm appropriate biodistribution. In the clinical trials before the approval of the regimen, only 1 patient (of approximately 400) was not treated with (90)Y-ibritumomab tiuxetan after imaging with (111)In-ibritumomab tiuxetan, because of altered biodistribution. The Zevalin Imaging Registry was established by Biogen Idec Inc. to identify cases of potential altered biodistribution and to collect clinical information in cases in which the regimen was not completed after imaging. METHODS: The registry surveyed treating physicians to verify completion of treatment with the ibritumomab tiuxetan therapeutic regimen in patients treated with (111)In-ibritumomab tiuxetan between March 27, 2002, and March 31, 2003. RESULTS: Survey data were collected on 953 of an estimated 1,144-1,192 patients in whom ibritumomab tiuxetan therapy was initiated (case capture rate of 80%-83%). Thirty-eight cases were reported in which a decision not to treat was made after imaging with (111)In-ibritumomab tiuxetan (4.0% of all cases captured); 16 of these were for imaging reasons, and 22 were for medical reasons. Twelve of the 16 imaging cases met the criteria for altered biodistribution (1.3%). Of these 12 cases, 6 (0.6%) were suspected to be true altered biodistribution and 6 appeared to be due to the use of a procedure for radiolabeling (111)In-ibritumomab tiuxetan that differed from that in the prescribing information. All cases of altered biodistribution were seen on the first image (2-24 h) after the administration of (111)In-ibritumomab tiuxetan. The 22 cases in which decisions not to treat were made for medical reasons accounted for 2.3% of the cases. The majority of these cases (19/22) were in patients who had an expected biodistribution but had a rapid change in their clinical condition that precluded treatment. CONCLUSION: The rate of true altered biodistribution was 0.6% in the Zevalin Imaging Registry, which collected treatment decisions based on data from approximately 80% of all patients treated commercially in the first year after drug approval. All cases of altered biodistribution were apparent on the first image, obtained at 2-24 h after the administration of (111)In-ibritumomab tiuxetan.

Antibodies, Monoclonal↗