Conrad E. Nagle

Reduction of Metastatic Load to Liver after Intraarterial Hepatic Yttrium-90 Radioembolization as Evaluated by [18F]Fluorodeoxyglucose Positron Emission Tomographic Imaging

PURPOSE To assess the response of hepatic metastases after treatment with intraarterial yttrium 90 radioembolization (ie, use of SIR-Spheres) with use of [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET). MATERIALS AND METHODS Nineteen patients with metastatic cancer to the liver from various solid tumors with progression despite polychemotherapy were included. All patients underwent baseline computed tomography, FDG PET, hepatic angiography, and intraarterial technetium 99 m macroaggregated albumin scan for assessment of lung shunting fraction. Patients were treated with 90Y resin microspheres on a lobar basis and were monitored for 3 months with use of dedicated attenuation-corrected PET. For each patient, regions of interest were drawn along the liver edge to measure total liver standard uptake value (SUV) on axial images, covering the entire liver. Visual estimates were also performed and graded as +1, 0, -1, -2, or -3 for progression, no change, and mild, moderate, and dramatic improvement by posttreatment PET. RESULTS The median absorbed dose for the tumor was 76 Gy. There was a significant overall decrease in total liver SUV after treatment (baseline, 71,134 +/- 38,055; after SIR-Sphere treatment, 59,941 +/- 26,509; P = .028) for the entire group. Visual estimates placed 15 patients (79%) in response categories (-3 to -1) and four patients (21%) in nonresponse categories (0 to +1) for the liver. The percentage change of total liver SUV after treatment in the response group (-19%) was significantly greater and different in direction than that in the nonresponse group (+27%; P = .03). This percentage change was also correlated significantly with the respective visual estimates (r = 0.72; P < .0005) for each individual patient. Three patients had major complications related to hyperbilirubinemia (transient, n = 1; permanent, n= 2). CONCLUSIONS The results suggest that there is significant reduction of hepatic metastatic load as evaluated objectively by PET after 90Y radioembolization for the treatment of unresectable metastatic disease to the liver. 90Y radioembolization provides encouraging results by arresting progression of metastatic cancer to the liver.

Indium-111 OncoScint CR/OV and F-18 FDG in colorectal and ovarian carcinoma recurrences. Early observations.

lndlum-111 satumomab pendetide (ln-111 OncoScint) planar and SPECT imaging and F-18 FDG positron emission tomography (PET) have been found individually to be helpful in the detection of recurrent colorectal and ovarian cancer, but have not been compared. Twelve patients who were examined for recurrent colorectal or ovarian carcinoma underwent both ln-111 OncoScint imaging and F-18 FDG PET imaging. All had normal or equivocal results of CT or MR studies. Tumor detection abilities were similar in most cases. However, Oncoscint demonstrated an advantage in the detection of carcinomatosls. PET demonstrated an advantage in detecting focal tumor recurrence in one case and, not unexpectedly, In detecting liver metastases. All positive nuclear studies for tumor were found to be true-positives at pathology (7 patients), or by diagnostic new CT changes (1 patient). Finally, unreported, bone marrow, bowel, and colostomy sites appear to be normal sites of localization of F-18 FDG 1 hour after injection.

A statistical investigation of normal regional intra-subject heterogeneity of brain metabolism and perfusion by F-18 FDG and O-15 H2O PET imaging

BackgroundThe definite evaluation of the regional cerebral heterogeneity using perfusion and metabolism by a single modality of PET imaging has not been well addressed. Thus a statistical analysis of voxel variables from identical brain regions on metabolic and perfusion PET images was carried out to determine characteristics of the regional heterogeneity of F-18 FDG and O-15 H2O cerebral uptake in normal subjects.MethodsFourteen normal subjects with normal CT and/or MRI and physical examination including MMSE were scanned by both F-18 FDG and O-15 H2O PET within same day with head-holder and facemask. The images were co-registered and each individual voxel counts (Q) were normalized by the gloabl maximal voxel counts (M) as R = Q/M. The voxel counts were also converted to z-score map by z = (Q - mean)/SD. Twelve pairs of ROIs (24 total) were systematically placed on the z-score map at cortical locations 15-degree apart and identically for metabolism and perfusion. Inter- and intra-subject correlation coefficients (r) were computed, both globally and hemispherically, from metabolism and perfusion: between regions for the same tracer and between tracers for the same region. Moments of means and histograms were computed globally along with asymmetric indices as their hemispherical differences.ResultsStatistical investigations verified with data showed that, for a given scan, correlation analyses are expectedly alike regardless of variables (Q, R, z) used. The varieties of correlation (rs) of normal subjects, showing symmetry, were mostly around 0.8 and with coefficient of variations near 10%. Analyses of histograms showed non-Gaussian behavior (skew = -0.3 and kurtosis = 0.4) of metabolism on average, in contrast to near Gaussian perfusion.ConclusionThe co-registered cerebral metabolism and perfusion z maps demonstrated regional heterogeneity but with attractively low coefficient of variations in the correlation markers.

Bile ascites in adults. Diagnosis using hepatobiliary scintigraphy and paracentesis.

Hepatobiliary scintigraphy has been recognized as a useful diagnostic tool in detecting the presence and site of bile leaks. The authors report a case of bile ascites secondary to a postsurgical biliary leak, the scintigraphic findings in bile ascites, and the potential use of paracentesis, in combination with hepatobiliary scintigraphy, in confirming the presence of bile ascites and a bile leak.

Unexplained Shoulder Pain in a Weight Lifter.

In brief: This case report describes how the authors diagnosed the shoulder pain of a weight lifter through the use of radionuclide imaging. This technique is especially valuable because it detects increased vascularity or increased metabolic activity of lesions long before such changes can be seen on plain radiographs or other imaging modalities.

Radionuclide Imaging of Musculoskeletal Injuries in Athletes with Negative Radiographs.

In brief: Radionuclide bone scans can be useful in the diagnostic evaluation of musculoskeletal injuries in athletes. Bone scans can detect shinsplints, stress fractures, and muscle injuries before they are detectable on radiographs. Prognosis can be accurately assessed, allowing appropriate treatment to proceed without delay. The authors discuss the use of bone scans and identify musculoskeletal injuries that are associated with specific sports, such as stress fracture of the femur (soccer), tibia (running), scapula (gymnastics), and pars interarticularis (football or lacrosse).

Cost-appropriateness of whole body vs limited bone imaging for suspected focal sports injuries.

Bone imaging has been recognized as a useful diagnostic tool in detecting the presence of focal musculoskeletal injury when radiographs are normal. A retrospective review of bone images in a small number of amateur athletes indicates that secondary injuries were commonly detected at sites different from the site of musculoskeletal pain being evaluated for injury. While a larger study will be necessary to confirm the data, this review suggests that it is medically justified and cost-appropriate to perform imaging of the entire skeleton as opposed to imaging limited to the anatomic site of pain and suspected injury.

Osteitis Pubis in a Basketball Player.

In brief:An 18-year-old male varsity basketball player complained of lower left abdominal pain of a months duration. Laboratory tests were normal, and no hernia was present. A computed tomography scan showed no abnormality, and fraying of the pubic bone along the symphysis was too subtle to detect on x-ray. A bone scan (pelvic views), however, confirmed a diagnosis of osteitis pubis. Although this disease is self-limited, the patient was treated with corticosteroids and anti-inflammatory medication to enhance his comfort. His condition gradually improved within a few months, and he returned to competition the following season. Follow-up bone scans at one and two years were normal.

Diagnostic Imaging of Intracranial Trauma

In brief: Sports-related head injuries are relatively common among both amateur and professional athletes. Although most of these injuries are not severe, they occur in a wide variety of sports at all levels of participation. Diagnostic imaging for these injuries has increased in importance over the past decade, and techniques have become more sophisticated and accessible. The authors present a case report of intracranial trauma in a competitive cyclist and describe the various imaging methods-computed tomography, magnetic resonance imaging, plain film radiography, and angiography-used to evaluate head injuries. Computed tomography is emphasized because it is more widely used than the other methods.

Computer-assisted Imaging and Display for Biliary Leak Detection

Hepatobiliary scintigraphy with Tc-99m IDA derivatives is a well-established imaging technique for the detection of various biliary tract disorders, including bile leaks. The most common cause of bile extravasation is biliary surgery, followed by penetrating abdominal trauma. Blunt abdominal injury and acute inflammation are rarer causes. A case of biliary extravasation caused by penetrating trauma is presented in which early identification of the leak and its she was made possible by dynamic display of the computer-acquired data.