Small left atrium: an adjunctive sign of hemodynamically compromised massive pulmonary embolism.

Pulmonary embolism (PE) is a common disease with a high mortality rate due to right ventricular dysfunction and underfilling of the left ventricle. We present a case of a 33-year-old man with hemodynamically compromised massive PE. His left atrium was collapsed with marked dilatation of the right atrium and ventricle on multi-detector-row CT scans. The patient was treated with an intracatheter injection of a mutant tissue-type plasminogen activator and subsequently showed clinical and radiological improvements. The small left atrial size in combination with a right ventricular pressure overload was considered to be an adjunctive sign of hemodynamically compromised massive PE.

Teaching radiology to military nursing students.

OBJECTIVES: To assess the students' perceptions and evaluations of radiology lectures and to determine the factors correlating with performance on examinations. METHODS: Sixty-three nursing students were asked to submit their opinions regarding the lecture at the end of each lecture, and they were asked to evaluate the lectures as a whole at the end of the course. Relationships between each of the survey items (student curiosity, overall understanding, usefulness of the lecture, difficulty level, incentive to study, and total number of opinions regarding the lecture) and the final examination score were examined with Spearman correlation analysis. RESULTS: Statistically significant positive correlations were found between student curiosity and the final examination score (n = 62, rs = 0.281, p < 0.028) and between the total number of opinions and the final examination score (n = 63, rs = 0.273, p < 0.032). However, the other variables did not reach statistical significance. CONCLUSIONS: Our results suggest that lectures enhancing student curiosity and eliciting feedback from students may be related to high performance on examinations.

Carcinoid tumor of the ampulla of Vater. Magnetic resonance imaging findings.

Carcinoid tumors arising from the ampulla of Vater are rare, and their magnetic resonance (MR) imaging findings have not been reported in the literature to date. We report a case of carcinoid tumor of the ampulla of Vater and discuss the characteristic MR imaging findings. The tumor was isointense relative to the muscle on both the T1- and T2-weighted images with heterogeneous enhancement after gadolinium administration. Both the common bile and the pancreatic ducts were dilated on the MR cholangiopancreatography.

Optimal particle size of radiocolloid for sentinel node identification in breast cancer-electron microscopic study and clinical comparison.

BACKGROUND: Sentinel node (SN) biopsy using a radiotracer is easy to learn, reproducible, and performed by the majority of breast cancer surgeons. However, this technique raises the question: what is the optimal particle size of colloid? METHODS: Patients were injected with conventional tin colloid (median particle diameter: 700 nm) and the predominant particle size of radiocolloid retained in the SN was measured using electron microscopy. This showed a narrow distribution of colloidal size (100-150 nm). Patients were then injected with modified tin colloid having a median particle size of 100 nm. A clinical comparison was performed between conventional particle size or reduced particle size tin colloid and the SN biopsy success rate, the number of SNs, and the colloidal uptake in SNs. RESULTS: A total of 118 patients were injected with the conventional tin colloid (group I) and 124 patients with the smaller particle colloid (group II). The identification rate and the number of SN in both groups were almost equal, and the patients with low-uptake SNs were not significantly less in group I(p = 0.55). However, in the subgroup of patients 60 years of age or more, group II had significantly more SNs than group I(1.4 vs 1.9; p = 0.03) and low-uptake SNs were significantly less common than in group I(p = 0.02). CONCLUSIONS: The improvement of colloidal uptake in SNs using the smaller particle size tin colloid was confirmed, and this impact was statistically significant in the older population.

Primary peritoneal clear cell carcinoma.

The computed tomography (CT) and magnetic resonance imaging findings of primary peritoneal clear cell carcinoma in a 53-year-old woman are reported. A CT scan showed a complex cystic mass with solid components that involved the right upper quadrant and displaced the liver and the right kidney. Magnetic resonance imaging revealed a multicystic mass with hemorrhage and heterogeneous solid protrusions. The diagnosis of primary peritoneal clear cell carcinoma was made by histopathologic study of the surgical specimen.

Utility of axillary ultrasound examination to select breast cancer patients suited for optimal sentinel node biopsy.

BACKGROUND: Because sentinel node (SN) biopsy (SNB) is known to produce false-negative results, we examined the usefulness of axillary ultrasound (AUS) in selecting patients suitable for optimal SNB. METHODS: A positive AUS finding (positive AUS) was defined as an echo pattern of a homogeneously hypoechoic SN without an echo-rich center, indicating massive to extensive nodal involvement. The identification of SNs was performed, and complete axillary dissection was carried out. RESULTS: A total of 262 women were enrolled into the study (T1 disease = 94; T2 disease = 145; and T3 disease = 23). The incidence of positive AUS increased with increasing size of breast tumor (P <0.0001). The overall identification and false-negative rates were 88.2% and 10.8%, respectively. However, when limited to AUS-negative patients, SNs were identified in 205 of 208 patients (98.6%), and the false-negative rate was 1.7%. CONCLUSIONS: AUS should be included in the preoperative procedure for the selection of breast cancer patients suitable for SNB.

Pleomorphic sarcoma of the adult urinary bladder: sonographic findings.

Sarcomas with muscular differentiation (eg, rhabdomyosarcoma, leiomyosarcoma, pleomorphic sarcoma) are uncommon in the adult urinary bladder. We report the sonographic findings in a case of pleomorphic sarcoma with muscular differentiation arising from the bladder dome that mimicked urachal carcinoma; findings of correlative imaging are also discussed.

Soft copy using image processing in place of hard copy for detection of subtle pulmonary lesions: is it actually cost-effective?

PURPOSE: To comparatively assess the interpretation performance of hard-copy versus soft-copy presentations for detecting subtle pulmonary lesions and to estimate soft-copy cost-effectiveness. METHODS: Computed radiography was used to obtain images with a 1,600x 1,200 matrix having 8 bits of gray-scale definition. The two separate image formats (hard and soft copy), which consisted of 60 chest radiograph combinations, were shown to five board-certified radiologists. The costs of hard copies, chemicals, waste disposal, and labor were calculated. RESULTS: The mean accuracies and Az values were 0.63 (hard) vs. 0.64 (soft) and 0.657 (hard) vs. 0.729 (soft), respectively. Reading one set of hard copies took on average 8.0 sec less than reading soft copies (30.3 vs. 38.3 sec). Estimated savings resulting from replacement of hard copy with soft were US$128,004 per year or US$6.20 per patient at our hospital. CONCLUSION: Conversion from hard copy to soft copy, using image processing, is feasible and cost-effective.

Invasive ductal carcinoma of the breast with a large central acellular zone associated with matrix-producing carcinoma.

Matrix-producing carcinoma is a variant of metaplastic carcinoma of the breast that consists of overt carcinoma with direct transition to a cartilagenous and osseous stromal matrix. A clinicopathological association between MPC and high-grade invasive ductal carcinoma with a large central acellular zone has been recently discussed. However, few reports have ever shown the radiological, pathological and immunohistochemical correlation of this unique tumor. We present a case of 27-year-old woman with matrix-producing carcinoma with a large central acellular zone, which was characterized by a large homogeneous hypodense center with well-marginated, ring-like enhancement on contrast enhanced computerized tomography.

J-tipped guidewire as a target for puncture of the subclavian artery in the placement of a reservoir port and catheter system.

The aim of this study was to verify the feasibility of using a J-tipped guidewire as a target for puncture of the subclavian artery in the placement of a reservoir port and catheter system (RPCS). Twenty-five patients with various hepatic malignancies underwent percutaneous implantation of an RPCS through the left subclavian artery for regional chemotherapy. To successfully puncture the left subclavian artery, a J-tipped guidewire was used as a target with fluoroscopic guidance. Technical success and complication rates, and numbers of puncture failures, were retrospectively analyzed. Implantation of the RPCS was successful in all patients. Eight (32%) patients had minor complications and no patient had major complications. The number of puncture failures per patient was 0 to 1 (mean=0.32). The J-tipped guidewire is a safe and appropriate target for puncture of the subclavian artery in the placement of an RPCS.

[Changes in national insurance reimbursement with introduction of the DPC package payment system for 131I therapy for hyperthyroidism].

The inpatient DPC package payment system lowers national insurance reimbursement as compared to the former fee-for-service payment system for inpatients, when an inpatient with hyperthyroidism or toxic multinodular goiter (TMNG) is admitted for 2-day radioiodine therapy. The differentials are 29,970 yen and 48,870 yen for a 2-day hospital stay for administration of 555 MBq and 925 MBq, respectively. We request the Health and Labor Ministry to newly establish the fee for 131I internal therapy for hyperthyroidism. Furthermore, the fee should be paid according to the fee-for-service payment system.

Does supplementation of CT and MRI with gallium-67 SPECT improve the differentiation between benign and malignant tumors of the head and neck?

UNLABELLED: The objective of our study is to determine whether 67Ga SPECT can supplement CT and/or MRI diagnostic information by visual comparison of the two separate data sets in patients with head and neck tumors. METHODS: A total of 50 patients with head and neck tumors (benign: 19, malignant: 31) were entered in the study. Three board-certified radiologists who had practical experience in interpreting both head and neck CT/MRI and 67Ga SPECT images, participated as readers. All of the CT and/or MR images of each patient were shown to each reader first, who after they had finished interpreting them were shown the 67Ga SPECT images. They were asked to score each image on a 7-point scale for the likelihood of the presence or absence of malignancy. Histological or cytological evaluation was done in all cases, and the radiologic studies were correlated with these findings. RESULTS: Improvement of all three readers' performance was from 70.7% to 83.3% in the mean accuracy and from 0.790 to 0.921 in the mean Az value (p = 0.033, 0.163, 0.105 in the Az values) after they were shown the 67Ga SPECT images. CONCLUSIONS: 67Ga SPECT should substantially increase confidence in the diagnosis of head and neck tumors when CT and/or MRI do not permit differentiation between benign and malignant disease.

Feasibility and cost-effectiveness of sentinel lymph node radiolocalization in stage N0 head and neck cancer.

OBJECTIVES: To determine the feasibility of sentinal lymph node (SN) radiolocalization and to assess the cost-effectiveness of the SN navigation surgery strategy in patients with stage N0 squamous cell carcinoma (SCC) of the head and neck. Patients Eleven consecutive patients with stage N0 SCC of the head and neck. METHODS: Head and neck lymphoscintigraphy was performed 2 hours after the injection of technetium Tc 99m tin colloid or phytate. A handheld gamma probe was used to detect the SN before and directly after making a skin incision. Nodes were evaluated histopathologically for micrometastasis. To determine the expected cost savings, a decision tree sensitivity analysis was designed based on the 2 competing strategies: ipsilateral neck dissection vs SN navigation surgery. The costs referred to billed costs based on the Japanese national insurance reimbursement system. RESULTS: The sensitivity of SN navigation surgery in our series was 100% (11/11) on a patient-by-patient basis and 94% (17/18) on a node-by-node basis. Micrometastasis was found in 36% (4/11). Assuming the micrometastasis prevalence, sensitivity, and specificity of navigation surgery for detecting SN to be 30%, 90%, and 100%, respectively, the decision tree sensitivity analysis showed that introduction of SN navigation surgery in place of ipsilateral neck dissection would yield cost savings of $1218 (US) per stage N0 patient in Japan and avoid 7 surgical deaths per 1000 patients who are supposed to undergo neck dissection in the neck dissection strategy. Break-even point analysis for the SN navigation surgery strategy showed that the threshold value required more than 41 patients for the savings to begin to accrue. CONCLUSION: Our results indicate that SN navigation surgery using radiolocalization is feasible and cost-effective, based on decision tree sensitivity analysis, in patients with stage N0 SCC of the head and neck.

Combined 201Tl and 67Ga brain SPECT in patients with suspected central nervous system lymphoma or germinoma: clinical and economic value.

BACKGROUND: Surgical resection is costly and an unfavorable prognostic factor for primary central nervous system (CNS) lymphoma and germinoma patients. OBJECTIVE: To assess the diagnostic and economic impact of combined 201Tl and 67Ga brain SPECT on the management of patients suspected of having CNS lymphoma or germinoma. METHODS: Sequential 201Tl and 67Ga brain SPECT was performed in 40 patients with cranial tumors to assess the diagnostic and economic impact of combined 201Tl and 67Ga SPECT on the management of patients suspected of having CNS lymphoma or germinoma. All intracranial masses were pathologically confirmed. The final diagnoses of a total of 47 foci were: 11 non-Hodgkin's lymphomas in 10 patients, 3 germinomas in 2 patients, 10 glioblastomas in 9 patients, 10 cerebral metastases in 8 patients, 13 meningiomas in 11 patients. Decision-tree sensitivity analysis for pretest probability regarding expected cost saving was performed for introduction of the combined study. RESULTS: All but one focus of CNS lymphomas or germinomas (92.9%, 13/14) exhibited more intense uptake of 67Ga than of 201Tl (p < 0.001). All foci of glioblastomas (10/10) and meningiomas (13/13), and 60% of metastatic foci (6/10) exhibited higher uptake of 201Tl than of 67Ga (p < 0.035). Expected cost saving in the 1% to 50% range of pretest probability of CNS lymphoma or germinoma would be from minus dollars 842US to plus dollars 2,047US per patient for introduction of the combined study, because of substitution of stereotactic biopsy for craniotomy. The pretest probability was the key factor for cost saving of the combined study. CONCLUSIONS: A 67Ga-positive and 201Tl-positive pattern with more intense uptake of 67Ga than 201Tl probably suggests CNS lymphoma or germinoma. This combination study appears to be cost-effective only in patients highly suspected of having CNS lymphoma or germinoma.

MRI findings of recurrent herpes simplex encephalitis in an infant.

We report the MRI findings of a 2-year-old boy with recurrent herpes simplex encephalitis (HSE). At the age of 14 months, the patient developed a high fever that lasted over 1 week and he did not receive appropriate treatment. At 6 months after the fever, MRI showed marked atrophic changes in both deep temporal lobes with hyperintensity in the hippocampi and parahippocampal gyri. Thirteen months after the first episode of the fever, the patient was diagnosed with recurrent HSE by polymerase chain reaction assay of the CSF; MRI at this time revealed diffuse cortical swelling. Hyperintensity on T2-weighted images was noted in the occipito-parietal cortex bilaterally, the left thalamus, the subcortical white matter and the splenium of the corpus callosum. Recurrence of HSE may be more common in infants than previously thought. It is important to consider the possibility of recurrent HSE and to understand that MRI findings in HSV1 encephalitis in infants and young children appear to differ from those observed in neonates, older children and adults.

Clinicopathologic and technical factors associated with the uptake of radiocolloid by sentinel nodes in patients with breast cancer.

PURPOSE: Sentinel-node biopsy is becoming widely accepted in breast cancer treatment. Using the radioisotope technique, a lower risk of identification failure is related to the amount of radiocolloid in the sentinel nodes. The aim of this study was to identify the factors associated with the colloidal uptake of the sentinel nodes. METHODS: Technetium-labeled colloid was injected peritumorally, with or without subdermal injection. According to the maximum radioactivity of the sentinel nodes, patients were divided into high (>/=100 counts/s) or low (<100 counts/s) uptake groups. The uptake was compared in relation to the clinicopathologic and technical features. RESULTS: The sentinel node was identified in 183 of 186 patients (98.4%), with 60 and 123 patients in the low- and high-uptake groups (mean: 39 and 1003 counts/s), respectively. Multivariate analysis showed that an age of 65 years or older and a sentinel-node size of 8 mm or more were significantly more predominant in the low-uptake group. CONCLUSION: Care must be taken when performing sentinel-node biopsy, especially for aged patients and for those with large sentinel nodes. The optimal technique should be determined on the basis of these results.

Magnetic resonance imaging findings of Machado-Joseph disease: histopathologic correlation.

PURPOSE: To determine the characteristic magnetic resonance imaging (MRI) findings of early- and late-stage Machado-Joseph disease (MJD) and to examine correlation with pathologic specimens. PATIENTS AND METHODS: Four patients genetically diagnosed with MJD and a familial case of MJD were all examined using MRI. Machado-Joseph disease was pathologically confirmed in one of the four genetically diagnosed patients, and the findings were compared with the MRI results. RESULTS: In all three patients who had MJD for less than 8 years, MRI confirmed mild cerebellar atrophy, particularly in the vermis, and atrophic changes in the superior cerebellar peduncle. Mild pontine atrophy was observed in these three patients. Atrophic changes in the pontine tegmentum were more prominent than those of the pontine base in these patients. Two of the three patients showed mild frontal atrophy. Of the five total patients, two had the disease for over 10 years and showed progressive atrophy of the brainstem and mild frontal atrophy. These two patients also showed pallidal atrophy. One autopsied case in which the disease duration was 17 years showed a typical pathologic picture of MJD. Macroscopic findings for this patient showed marked atrophy of the pons, mild cerebellar atrophy (particularly in the vermis), marked atrophy of the superior cerebellar peduncle, severe involvement of motor nuclei, and atrophy and discoloration of the pallidum and subthalamic nuclei. CONCLUSION: In the early stages of MJD, mild pontine atrophy, particularly in the tegmentum, and mild cerebellar atrophy are typical MRI findings. Atrophic changes in the brainstem may be progressive. Pallidal atrophy may be observed in patients with long disease duration. These findings correlated with the pathologic findings.