Technetium-99m-DTPA-galactosyl human serum albumin liver scintigraphy evaluation of regional CT/MRI attenuation/signal intensity differences.

UNLABELLED: Regional attenuation/signal intensity differences seen on CT/magnetic resonance imaging can be a clue in detecting regional hepatic blood flow abnormality. Sometimes, however, they can be misinterpreted as a hepatic neoplasm or, in the case of a true neoplasm, they can lead to an overestimation of its size because these regions often have similar attenuation or signal intensity to hepatic neoplasms. We evaluated 99mTc-diethylenetriaminepentaacetic acid-galactosyl human serum albumin (99mTc-DTPA-GSA) liver scintigrams in patients manifesting regional attenuation/signal intensity differences to further analyze the findings. METHODS: Technetium-99m-DTPA-GSA scintigrams of 23 patients with regional attenuation/signal intensity differences in the liver at dynamic contrast-enhanced CT/magnetic resonance imaging were evaluated. The causes of the differences were arterioportal (AP) shunts in seven patients, decreases in the portal venous flow in seven patients, occlusion of right hepatic vein in one patient, confluent hepatic fibrosis in one patient and unknown in seven patients. The accumulation of 99mTc-DTPA-GSA was compared with each known cause of attenuation/signal intensity difference. Count ratios of the regions to normal hepatic parenchyma also were calculated in all cases. RESULTS: In AP shunts, none of seven patients showed any decreased accumulation in the region. Accumulation of 99mTc-DTPA-GSA decreased in six of seven patients who had decreases in portal venous flow; this incidence was significantly higher than that in patients who had AP shunts (p < 0.005). In cases of unknown cause, two of seven patients showed a decrease in accumulation, but the other five showed no such decrease. The one patient with occlusion of the right hepatic vein showed no decrease, but the confluent hepatic fibrosis showed a significant decrease. The count ratio in AP shunts was significantly larger than that of the decrease in the portal venous flow (p < 0.005). CONCLUSION: Technetium-99m-DTPA-GSA accumulation in AP shunts has a different pattern from that found in patients with a decrease in portal venous flow. Therefore, differentiation between AP shunts, which showed no decrease in 99mTc-DTPA-GSA accumulation, and hepatic neoplasms can be made more easily.

Lobar decrease in 99mTc-GSA accumulation in hilar cholangiocarcinoma.

UNLABELLED: Hilar cholangiocarcinoma can obstruct hepatic ducts and involve the portal veins. Both biliary stasis and decrease in portal venous flow are known to reduce 99mTc-diethylenetriamine pentaacetic acid-galactosyl human serum albumin (GSA) accumulation. The specific relationship between these pathological conditions due to hilar cholangiocarcinomas and 99mTc-GSA accumulation has never been clarified. METHODS: Sixteen patients with hilar cholangiocarcinomas who underwent 99mTc-GSA liver scintigraphy were reviewed. The relationship between significant decrease in 99mTc-GSA accumulation and lobar biliary stasis, or decrease in the portal venous flow, was evaluated. Average counts of region of interest placed in both right and left lobes were compared in the same transaxial SPECT section. Count ratios of right and left lobes were calculated. RESULTS: Significant lobar decrease in 99mTc-GSA accumulation was observed in 6 of the 16 patients. Ipsilateral portal venous stenosis or obstruction was seen in all these 6 patients, whereas ipsilateral portal venous stenosis or obstruction was seen in only 1 of the other 10 patients. Symmetric bile duct dilatation was seen in 13 patients, and asymmetric bile duct dilatation was seen in 3. Lobar decrease in 99mTc-GSA accumulation correlated well with decrease in ipsilateral portal venous flow (P < 0.0005). The count ratio was significantly reduced when unilateral portal venous flow decreased (P < 0.05). CONCLUSION: Using 99mTc-GSA liver scintigraphy, we can predict lobar decrease in ipsilateral portal venous flow and monitor hepatic functional lateralities in patients with hilar cholangiocarcinomas.

Flare response seen in therapy for osteomalacia.

We report an interesting case of osteomalacia in which flare response was seen during therapy. The first 99mTc-methylene diphosphonate bone scan showed increased bilateral and symmetric uptake in the ribs, clavicles and iliac bones. Thoracic CT showed symmetric radiolucent seams (Looser's zones) in both ribs, which were pathognomonic of osteomalacia. After initiation of therapy with vitamin D, the patient's subjective symptoms gradually were relieved. On a second bone scan 4 mo. after initiation of therapy, the hot spots in the ribs remained unchanged. Uptake in the bilateral clavicles had become more intense, and new hot spots were recognized in the right lower ribs and left tibia. A third bone scan after 10 mo. demonstrated an obvious decrease in the number and intensity of the hot spots. Increased uptakes in the second scan were thought to be a flare response caused by therapy.

Comparison of differential diagnostic capabilities of 201Tl scintigraphy and fine-needle aspiration of thyroid nodules.

UNLABELLED: We assessed the ability of 201TI planar scintigraphy and fine-needle aspiration (FNA) biopsy to differentiate malignant from benign lesions by comparing the findings of these techniques with those of surgical histopathology for 107 patients with 109 thyroid nodules. METHODS: 201TI (74 MBq) was injected intravenously, and an early image and a delayed image were acquired after 10 and 120 min, respectively, for 10 min each. For 201TI planar scintigraphy, accumulation of the tracer in the nodules was visually scored and the nodules were grouped. Group A showed high activity in both early and delayed images. Group B revealed high activity in only the early image. Group C showed activity in the early image equal to that in normal tissues. Quantitative calculation of the washout rate was less than 0 in group CI and 0 or higher in group CII. Group D revealed low activity in the early image and variable activity in the delayed image. Three differential diagnosis methods were used for 201TI planar scintigraphy: method 1, in which only group A was considered malignant; method 2, in which both group A and group B were considered malignant; and method 3, in which groups A, B and CI were considered malignant. FNA results were assessed and classified by experienced pathologists. Two differential diagnosis methods were used for FNA: method a, in which malignancy was assigned to class IV (probably malignant or higher), and method b, in which malignancy was assigned to class III (possibly malignant or higher). RESULTS: Concerning 201TI methods 1, 2 and 3, sensitivity was 74.0%, 84.0% and 92.0%, respectively; specificity was 83.1%, 64.4% and 54.2%, respectively; and accuracy was 78.9%, 73.4% and 71.6%, respectively. For FNA, method a and method b had a sensitivity of 36.0% and 50.0%, respectively, and a specificity of 96.6% and 84.7%, respectively. The accuracy of both methods was 68.8%. For follicular lesions, sensitivity ranged from 80.0% to 90.0% for 201TI scintigraphy and from 10.0% to 30.0% for FNA. CONCLUSION: 201TI planar scintigraphy was found to be easier to use and more accurate than FNA in the differentiation of diagnosis of benign and malignant thyroid nodules based on visual scoring combined with quantitative evaluation.

Assessment of secondary necrosis of Jurkat cells using a new microscopic system and double staining method with annexin V and propidium iodide.

Using a new system developed by us for acquiring microscopic images automatically, we compared the morphological changes that apoptotic cells undergo with changes in the staining pattern of annexin V-enhanced green fluorescent protein (AV-EGFP) and propidium iodide (PI) in individual cells. Jurkat cells were treated with 5 mM CaCl2 alone, anti-Fas antibody and heating at 42 degrees C for 30 min or 46 degrees C for 60 min, and then were incubated in medium with 5 mM CaCl2. Time-lapse DNA fragmentation analysis and morphological observation revealed that the anti-Fas antibody and heating at 42 degrees C for 30 min induced typical apoptosis in the cells, and heating at 46 degrees C for 60 min induced typical necrosis. Time-lapse observation of individual cells stained with AV-EGFP and PI confirmed that apoptotic cells were stained at first with AV-EGFP alone, and thereafter also with PI when the cellular membrane ruptured and the cell underwent secondary necrosis. Most of the cells which underwent necrosis were stained simultaneously with AV-EGFP and PI. There was a significant time interval between the staining of individual cells with AV-EGFP, indicating apoptosis, and staining of these cells with PI, which indicated the occurrence of secondary necrosis. These results suggest that time-lapse examinations are necessary to distinguish apoptosis, secondary necrosis and necrosis in cells from one another. This study presents direct evidence that apoptotic cells undergo secondary necrosis, which could be recognized with PI.

The effect of calcium on Fas-mediated apoptosis and secondary necrosis of Jurkat cells.

Our previous study using a new microscopic system indicated that apoptotic cells undergo secondary necrosis during treatment with anti-Fas antibody and calcium. In this study, we compared the time-lapse appearance of apoptosis and secondary necrosis of Jurkat cells during treatment with anti-Fas antibody with and without calcium in individual cells. Apoptosis developed in 97% and 81% of cells during 36-hour-treatment with anti-Fas antibody with and without calcium, respectively. The apoptosis of Jurkat cells showed a characteristic pattern of time-lapse morphological change. Less than 1% of the apoptotic cells divided into apoptotic bodies. There was budding in all the other apoptotic cells, but no apoptotic bodies formed. We confirmed that secondary necrosis occurs in individual apoptotic cells during treatment with anti-Fas antibody. Neither the pattern of time-lapse morphological change nor the time interval between the beginning of apoptotic budding and secondary necrosis were related to the presence of calcium. This study clarified the characteristic pattern of time-lapse morphological change in Jurkat cells during treatment with anti-Fas antibody, and presented direct evidence that individual apoptotic cells undergo secondary necrosis. The presence of calcium did not affect the pattern of morphological change or the time interval between the beginning of apoptotic budding and secondary necrosis.

Overexpression of manganese superoxide dismutase gene suppresses spontaneous apoptosis without a resultant alteration in in vivo growth of the mouse fibrosarcoma, FSa-II.

The relationship between spontaneous apoptosis and overexpression of manganese superoxide dismutase (MnSOD) gene was examined in vivo. The mouse fibrosarcoma cells expressing high MnSOD activities due to transfection with the human MnSOD cDNA (SOD-H), or the fibrosarcoma cells transfected with the selectable marker alone (NEO), were transplanted into immune-deficient Fox Chase SCID C.B-17/Icr-scid Jcl mice. Apoptosis in tumors was visually quantified by the in situ end-labeling method. The number of apoptotic cells in the SOD-H tumors was significantly less than that in the NEO tumors. The tumor growth time of the SOD-H tumors to grow from 34 to 500 mm3 in one-half of the mice was slightly longer than that of the NEO tumors, but the difference was not statistically significant. These results suggest that overexpression of MnSOD gene is involved in the suppression of spontaneous apoptosis, without a resultant alteration in the tumor growth.

Nontumorous decrease in Tc-99m GSA accumulation.

Nontutimorous decrease in 99mTc-GSA accumulation has not been well covered in the literature. Understanding of this phenomenon is, however, essential for accurate evaluation of regional hepatic function. Scintigrams (transaxial SPECT) of 269 patients who underwent 99mTc-GSA liver scintigraphy were reviewed for the presence of nontumorous decreases in 99mTc-GSA accumulation. Nontumorous decreases in 99mTc-GSA accumulation were seen in 32 of 269 patients (12%). In 16 of the 32 patients (6%), nontumorous decreases in 99mTc-GSA accumulation corresponded to regional decrease in portal venous flow. The causes of such decrease in portal venous flow were portal thrombus of hepatocellular carcinomas in eight patients, portal venous stenosis or occlusion by hilar cholangiocarcinomas in five patients, inter alia. In eight patients (3%), the regions with decreased 99mTc-GSA accumulation correlated with massive hepatic necrosis in fulminant hepatitis, scar in hepatitis, or confleuent in portal venous flow, lobar biliary stasis, or both. In four patients (1.5%), the exact causes of nontumorous decrease in 99mTc-GSA accumulation could not be determined.

Detection of hepatic metastasis from medullary thyroid cancer with Tc-99m-MIBI scintigraphy in a patient with Sipple's syndrome.

We report a case of Sipple's syndrome with a hepatic tumor. A 28-year-old male with medullary thyroid cancer and bilateral pheochromocytomas was diagnosed as having Sipple's syndrome. The hepatic tumor was found to be hypervascular by means of a dynamic abdominal CT scan. An I-131-MIBG scan showed no increased accumulation in the tumor. A whole body Tc-99m-MIBI scan had shown, however, increased accumulation in the tumor by 10 minutes after i.v. Tc-99m-MIBI. The hepatic tumor was diagnosed histologically as a metastasis from the medullary thyroid cancer. To our knowledge, there have been no previous reports of increased Tc-99m-MIBI accumulation in hepatic metastases from medullary thyroid cancer.

Kinematic magnetic resonance imaging (MRI) of the normal shoulder: assessment of the shapes and signals of the superior and inferior labra with abductive movement using an open-type imager.

A preliminary study was conducted to evaluate the superior and inferior glenoid labra with abductive movement using an open-type MR unit in asymptomatic healthy volunteers. Both fast low angle shot (FLASH) and turbo spin echo (TSE) images were obtained to evaluate the shapes of both the superior and inferior labra, as well as to assess changes in signal at these sites. As the abduction angle was increased, the shape of the superior labrum changed from round or triangular to crescentic and a higher signal was frequently seen. At an abduction angle of 150 degrees, an increase in signal was seen in one-half of the superior labra; this increase was noted more frequently in volunteers over 40 years of age. In some of the superior labra, the increase in signal seen at 150 degrees abduction disappeared on subsequent images obtained at 0 degrees abduction. Hence, the increase in signal was considered to be a reversible change. The shape of the inferior labrum tended to change from crescentic to triangular or round. An increase in signal in the inferior labrum was unrelated to the abduction angle. Abductive kinematic studies using an open-type MR unit provides information about the morphology of the superior and inferior labra, as well as information about signal changes occurring at these sites.

Attenuation changes in periportal region during triple-phasic contrast-enhanced CT.

OBJECTIVE: To evaluate attenuation changes in the periportal regions of the liver during triphasic contrast CT. MATERIALS AND METHODS: The study group consisted of 93 patients, all of whom underwent triphasic contrast-enhanced CT with a helical scanner for survey of liver disease. The three phases included the arterial phase, portal venous phase, and equilibrium phase. Attenuation changes in the periportal area in each phase were evaluated in every patient. Factors surmised to be related with periportal low attenuation, including elevation of venous pressure, presence of ascites, cardiac enlargement, and lymphadenopathy of the porta hepatis and lesser omental region, were also evaluated. RESULTS: Periportal low attenuation was seen in 65 patients (69.8%) in the portal venous phase where the liver parenchyma showed the largest attenuation value. Among them, periportal low attenuation was continuously observed in every phase in 13 patients (13.9%), while it was confirmed only in the portal venous phase in 28 patients (30.1%), and in 24 patients (32.2%) in the portal venous phase plus either the arterial or equilibrium phase. None of the factors that were investigated could be related to the appearance of periportal low attenuation. CONCLUSION: Periportal low attenuation was a relatively common finding in the portal venous phase of triphasic contrast CT, whereas it was less usual in the arterial or equilibrium phase.

Endometrial carcinoma: multisection dynamic MR imaging using a three-dimensional FLASH technique during breath holding.

PURPOSE: Our aim was to investigate the usefulness of multisection dynamic MR imaging using a 3D FLASH technique during breath holding in assessing myometrial invasion by endometrial carcinoma. MATERIALS AND METHODS: Twenty-eight endometrial carcinomas were evaluated with pathologic correlation. Dynamic MR imaging was performed using the 3D FLASH technique during breath holding. We compared accuracy in the assessment of myometrial invasion by endometrial carcinoma between T2-weighted images, contrast-enhanced T1-weighted images, and dynamic MR images. RESULTS: The accuracy rates in estimating myometrial invasion with T2-weighted images, contrast-enhanced T1-weighted images, and dynamic MR images were 64.3%, 67.8%, and 85.7%, respectively. Statistically significant differences were seen between dynamic MR images and both T2-weighted images and contrast-enhanced T1-weighted images. CONCLUSION: Multisection dynamic MR imaging using the 3D FLASH technique during breath holding is useful for the evaluation of myometrial invasion by endometrial carcinoma with polypoid growth or an unclear junctional zone on T2-weighted images.

MR appearance of endometrial carcinoma and mucinous cystadenoma in a postmenopausal patient treated with tamoxifen for breast cancer.

We present a case of endometrial carcinoma accompanied with mucinous cystadenoma in a 70-year-old postmenopausal woman treated with tamoxifen for breast cancer demonstrated by MR imaging. Tamoxifen therapy (20 mg/day) had been carried out for more than 11 years since the surgical procedure for the primary tumor. MR images showed a markedly enlarged uterus containing endometrial carcinoma, cystic atrophy of the endometrium, and a right adnexal mass with multicystic components of various signal intensities.

Reduced radioactivity in the periphery of the liver in a patient with idiopathic portal hypertension.

The authors report a case of idiopathic portal hypertension in which radioaccumulation in the peripheral region of the liver decreased markedly. On dynamic CT, peripheral regional enhancement of the liver was seen in the arterial phase. The region was hypointense on T1-weighted MR images and hyperintense on T2-weighted images. On portograms via the superior mesenteric artery, markedly decreased portal venous perfusion was seen in the peripheral region of the liver. Tc-99m galactosyl human serum albumin (GSA) liver scintigrams showed decreased accumulation in the peripheral region and unchanged accumulation in the central region of the liver. Tc-99m GSA liver scintigraphy clearly showed localized liver dysfunction in the peripheral region.

I-123 uptake in nonfunctional struma ovarii.

A case of nonfunctional struma ovarii preoperatively diagnosed by scintigraphy of the pelvis using I-123 NaI is reported. US, CT, and MRI revealed a multilobulated mass composed of cystic and solid components. CT showed cystic components with slightly high density and MRI showed various signal intensities on T1- and T2-weighted images. I-123-scintigraphy of the pelvis showed uptake in the pelvic mass. Microscopic examination revealed the histologic appearance of thyroid tissue accompanied by follicular adenoma. I-123 scintigraphy of the pelvis was useful for reaching the correct preoperative diagnosis in this patient with nonfunctional struma ovarii.

[Anatomic variants of the cystic duct and cysticohepatic junction: diagnosis with MR cholangiography].

The cystic duct are variable in length, course and site of termination. A knowledge of the variable anatomy of the cystic duct and cysticohepatic junction is important in biliary surgery, because failure to recognize anatomic variations may result in a significant ductal injury. Magnetic resonance cholangiography (MRC) is a recently developed technique that demonstrates the biliary tree noninvasively and without injection of contrast material. Anatomic variants of the cystic duct and cysticohepatic junction that may increase the risk of bile duct injury in biliary surgery are frequently identified with MRC. MRC will be a noninvasive and a useful technique in the diagnosis of anatomic variants of the cystic duct and cysticohepatic junction.

[Quantitative evaluation of regional blood flow in pulmonary sarcoidosis with bull's eye analysis].

Lung perfusion scintigraphy was performed in 23 patients with pulmonary sarcoidosis and in 11 normal volunteers. Bull's eye analysis was used to analyze regional pulmonary blood flow quantitatively. First, whole lung perfusion images were divided into three regions by three concentric circles. Then radial axes were projected from the center to define 36 x 10 degrees sectors. The counts for each sector were calculated and a Bull's eye image was displayed. The counts were compared with the lower limit of normal (mean - 2SD), and as the indices of reduction in perfusion, extent score (ES) and severity score (SS) were calculated. ES and SS showed significant reduction in perfusion 16 patients (70%) with sarcoidosis. In stage II sarcoidosis, both ES and SS were significantly higher than in stage I sarcoidosis (p less than 0.05). In comparison with the findings of transbronchial lung biopsy, both ES and SS had correlations with the degree of alveolitis and ES had a correlation with the degree of angiitis. Both ES and SS have no correlation with 67Ga scintigraphy findings. In comparison with clinical data, ES had a positive correlation with serum angiotensin-converting enzyme activity (p less than 0.05), and SS had a significant positive correlation with bronchoalveolar lavage fluid.CD+/CD8+ ratio (p less than 0.05). The Bull's eye analysis was considered useful for the quantitative evaluation of regional pulmonary blood flow in pulmonary sarcoidosis, and it was suggested that the mechanism of reduction in perfusion might be resulted mainly in its alveolitis and angiitis. Ventilation abnormality, which may happen prior to reduction in perfusion, may be an important factor of reduction in perfusion.

[A new application of bull's-eye analysis to lung perfusion scintigraphy].

Technetium-99m macroaggregated albumin lung perfusion scintigraphy was performed and evaluated semiquantitatively by bull's-eye analysis in 24, including 7 with central pulmonary carcinoma, 3 with hypersensitivity pneumonitis (HP), 3 with diffuse panbronchiolitis (DPB) and 11 normal subjects. First, whole lung field was divided into three regions by three concentric circles. And then radial axes were projected from the center to define 36 sectors, 10 degree each. The counts of each sector was calculated and bull's-eye image and circumferential profile curve were displayed. The patient's map was compared with the lower limit of normal (mean-2 SD), and the extent score (ES) and the severity score (SS) were calculated. The ES was 0.25 +/- 0.12 in pulmonary carcinoma (n = 7), 0.08 +/- 0.07 in HP (n = 3), 0.06 +/- 0.04 in DPB (n = 3). The SS was 26.39 +/- 15.17 in pulmonary carcinoma, 4.75 +/- 5.57 in HP, 4.29 +/- 3.67 in DPB. In one case of central pulmonary carcinoma, segmental perfusion defect was evaluated semiquantitatively by bull's-eye image and circumferential profile curve. And in one case of HP, the change of regional pulmonary blood flow could be followed easily using extent and severity map. This new application of Bull's eye analysis to lung perfusion scintigraphy might be useful to evaluate regional pulmonary blood flow.