Blood flow change quantification in cervical cancer before and during radiation therapy using perfusion CT

The purpose of this study was to quantify the changes of tumor blood flow (BF) in cervical cancer after radiation therapy by using perfusion computed tomography (CT), and to examine the difference between maximum slope (MS) and single-input one-compartment model (SOCM) methods. Fourteen consecutive patients who received definitive radiation therapy for cervical cancer from October 2009 to February 2010 were enrolled in this study. Blood flow (BF) analyses were performed using both MS and SOCM methods. Quantitative BF maps were created using Body Perfusion (Toshiba Medical Systems, Co. Tokyo, Japan). Perfusion color maps were successfully created by the two analytical methods. BF of the tumors was clearly higher than that of normal cervix, making it possible to distinguish tumor tissue from normal cervical tissue. BF of the tumors after 20 Gy of radiation therapy calculated by the MS method was significantly larger than that before treatment (126.9 vs. 72.2 ml/min/100 ml, median; p < 0.05). Although BF calculated by the MS and SOCM methods showed a positive linear correlation (p < 0.001, r = 0.981), BF calculated by the MS method was lower than that obtained by the SOCM method (103.7 vs. 115.1 ml/min/100 ml, p < 0.01). The change of tumor BF in cervical cancer before and after radiation therapy can be monitored by conducting blood flow analysis using perfusion CT. BF by the MS method was lower than that by the SOCM method, but the two analytical methods correlated well. Perfusion CT may have potential in noninvasive monitoring of vascular and oxygenation status and for guiding adaptive therapy.

Relationship of parental bonding styles with gray matter volume of dorsolateral prefrontal cortex in young adults

Previous epidemiologic studies using the parental bonding instrument (PBI), a self-report scale to rate attitudes of parents during the first 16 years, have suggested that a lower parental care score or higher parental overprotection score could lead to an increased risk of several psychiatric disorders, including schizophrenia and mood disorder. However, neuroimaging studies of an association between PBI scores and brain developmental abnormalities are still limited. In this region-of-interest analysis study using a cross-sectional design, we examined 50 normal young adults, in terms of relationships of parental bonding styles during the first 16 years measured by PBI with regional gray matter (GM) volume in the dorsolateral prefrontal cortex (DLPFC). Our study showed that paternal care score positively correlated with the GM volume in the left DLPFC, and paternal and maternal overprotection score negatively correlated with the GM volume in the left DLPFC. In conclusion, our results suggest that in normal young adults, lower paternal care and higher parental overprotection scores correlated with the GM volume reduction in the DLPFC.

Added value of contrast-enhanced CISS imaging in relation to conventional MR images for the evaluation of intracavernous cranial nerve lesions

INTRODUCTION

The normal cranial nerves (CNs) of the cavernous sinus can be clearly demonstrated using contrast-enhanced constructive interference in steady-state (CISS) magnetic resonance imaging (MRI). This study used the method to evaluate pathological CNs III, IV, V(1), V(2), and VI in cavernous sinuses affected by inflammatory and neoplastic diseases.

METHODS

MR images from 17 patients with diseases involving the cavernous sinuses and/or causing neuropathy in CNs III-VI were retrospectively evaluated. The patients were divided into inflammatory (n=11) and neoplastic (n=6) groups. We defined CNs as abnormal when they exhibited enlargement or enhancement. CNs were evaluated using both contrast-enhanced CISS and T1-weighted MRI.

RESULTS

In the inflammatory group, abnormal CNs were identified by contrast-enhanced CISS MRI in 13 of 25 symptomatic CNs (52%) in eight patients, but in only two CNs (8%) in two patients by contrast-enhanced T1-weighted MRI. In the neoplastic group, both sequences of contrast-enhanced CISS and T1-weighted MRI detected abnormalities in the same three of eight symptomatic CNs (37.5%), i.e., the three CNs were all in the same patient with adenoid cystic carcinoma.

CONCLUSION

Contrast-enhanced CISS MRI is useful for detecting CN abnormalities in inflammatory pathological conditions of the cavernous sinuses.

[Evaluation of exposure dose for panoramic radiography]

PURPOSE

There is no established method to determine a diagnostic reference level of panoramic radiology. As the basic principle of the panoramic radiology dose index (PRDI) and CT dose index (CTDI) is almost identical, we evaluated the usefulness of PRDI for this purpose.

METHODS

Using the imaging plate (IP) sandwiched between the 160-mm thick acrylic disks, horizontal radiation dose distribution was analyzed by the conventional radiographic technique. Panoramic exposure dose was measured using the CT ionizing chamber that was placed at the tracking focus. Beam height was used as measurement unit, and PRDI was normalized and calculated.

RESULTS

There were two foci showing the maximum exposure dose for this panoramic equipment, located symmetrically 45 mm away from the center of the object. The PRDI of medium-sized individuals measured by this method was 0.74 mGy.

CONCLUSION

We suggested a method to evaluate a diagnostic reference level, measuring the dose of exposure focus, i.e., maximum dose on panoramic radiology.

The role of the ADC value in the characterisation of renal carcinoma by diffusion-weighted MRI

The purpose of this study is to evaluate the role of diffusion-weighted imaging (DWI) in combination with T(1) and T(2) weighted MRI for the characterisation of renal carcinoma. The institutional review board approved the study protocols and waived informed consent from all of the patients. 47 patients (32 male and 15 female; age range, 21-85 years; median age, 65 years) who had suspected renal lesions on abdominal CT underwent MRI for further evaluation and characterisation of the lesions from April 2005 to August 2007 in our university hospital. A region of interest was drawn around the tumour area on apparent diffusion coefficient (ADC) maps. Final diagnosis was confirmed by histological examination of surgical specimens from all patients. The ADC value was significantly higher in renal cell carcinoma (RCC) than in transitional cell carcinoma (2.71+/-2.35 x 10(-3) mm(2) s(-1) vs 1.61+/-0.80 x 10(-3) mm(2) s(-1); p = 0.022). While analysing the histological subtypes of RCC, a significant difference in ADC values between clear cell carcinoma and non-clear cell carcinoma was found (1.59+/-0.55 x 10(-3) mm(2) s(-1) vs 6.72+/-1.85 x 10(-3) mm(2) s(-1); p = 0.0004). Similarly, ADC values of RCC revealed a significant difference between positive and negative metastatic lesions (1.06+/-0.38 x 10(-3) mm(2) s(-1) vs 3.02+/-2.44 x 10(-3) mm(2) s(-1); p = 0.0004), whereas intensity on T(1) and T(2) weighted imaging did not reach statistical significance. In conclusion, DWI has clinical value in the characterisation of renal carcinomas and could be applied in clinical practice for their management.

Relationship between age at onset and magnetic resonance image-defined hyperintensities in mood disorders

OBJECTIVES

To examine in patients with mood disorders the relationship of age at onset with the location and degree of MRI-defined brain hyperintensities.

METHOD

Fifty-two patients diagnosed as having mood disorders and 14 controls participated in the study. Brain MR images were analyzed according to semiquantitative ratings for the anatomical distribution and severity of T2-weighted hyperintensities. We compared these hyperintensities among the three age- and sex-matched groups of late-onset mood disorder patients (LOM), early-onset mood disorder patients (EOM), and controls. The time since the onset of disorder was significantly longer in the EOM than in the LOM group. We also conducted linear multiple regression analysis using the severity of hyperintensities as dependent variable to determine whether the clinical features correlate with vascular pathology.

RESULTS

As for deep white matter hyperintensity (DWMH), LOM exhibited higher ratings than EOM; as for brain areas, significant between-group differences were detected in the bilateral frontal areas and in the left parieto-occipital area. No significant difference was observed between EOM and controls. As for periventricular hyperintensity, there was no difference among the three groups. We obtained a significant regression model to predict DWMH ratings; age, number of ECTs, and LOM were selected as significant variables.

CONCLUSION

The present study suggests that the time since the onset of disorder does not affect the development of white matter lesions, but that white matter lesions are associated with late-onset mood disorders. The frontal areas and the left parieto-occipital area would be important for the development of late-onset mood disorders.

Brain metabolic changes associated with predispotion to onset of major depressive disorder and adjustment disorder in cancer patients--a preliminary PET study

OBJECTIVES

To explore neurobiological risk factors for major depressive disorder (MDD) and adjustment disorder in cancer patients by examining regional brain metabolism before psychiatric manifestation using positron emission tomography and by prospectively observing depressive and anxiety symptoms.

METHOD

Cancer patients who showed no psychiatric symptoms when they underwent 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) were followed up for one year using the Hospital Anxiety and Depression Scale (HADS). Fourteen patients who showed high HADS scores and 14 patients who showed low HADS scores were assessed by a psychiatrist 2 years after the PET scan and grouped into the deterioration group (n=10) and the no-change group (n=9). 18F-FDG PET images were analyzed to examine the difference in local brain glucose metabolism between the two groups.

RESULTS

The deterioration group showed a decreased glucose metabolism in the right medial frontal gyrus (BA6) and an increased glucose metabolism in the right posterior cingulate (BA29), right anterior cingulate (BA25), left subcallosal gyrus (BA25), and left caudate compared with the no-change group.

CONCLUSION

Cancer patients who later developed MDD or adjustment disorder showed regional brain metabolic changes. These regions may be associated with vulnerability to the onset of MDD or adjustment disorder in cancer patients.

Perfusion CT of breast carcinoma: arterial perfusion of nonscirrhous carcinoma was higher than that of scirrhous carcinoma

RATIONALE AND OBJECTIVES

Our goals were to apply perfusion CT technique to breast tumor and to evaluate the correlation between arterial perfusion value and other tumor characteristics.

MATERIALS AND METHODS

Thirty-one female patients with primary breast tumors were included in this study. A single-slice dynamic CT was performed after an intravenous bolus injection of contrast material (40 ml; 370 mg I/ml) at 8 ml/sec. The parameters were calculated on a pixel-by-pixel basis by using maximum slope method, and quantitative maps of arterial perfusion were created. Statistical correlation between tumor size, patient age, and perfusion were assessed. Differences in perfusion between scirrhous and nonscirrhous carcinoma were also assessed.

RESULTS

Perfusion CT images were successfully created for 24 patients (mean age, 55.9 years old; range, 36-85 years). In five patients, dynamic CT was not performed due to lack of visualization of the breast tumor on unenhanced CT. In two patients, reliable perfusion CT image could not be created because of motion artifact. The mean perfusion for 24 tumors was 33.1 +/- 16.9 ml/min/100 ml (mean +/- SD; range, 14-78), and the tumor perfusion did not correlate with patient's age or tumor size (21.0 +/- 10.2 mm; range, 10-45 mm). The mean perfusion of nonscirrhous carcinoma (45.8 ml/min/100 ml; n = 11) was higher than that of scirrhous carcinoma (22.7 ml/min/100 ml; n = 11; P < .001).

CONCLUSION

Determination of the perfusion of breast carcinoma is feasible by dynamic CT and can be performed during a routine CT study without much supplementary burden on the patient. There are differences in blood flow between scirrhous and nonscirrhous breast carcinoma, and further research is needed to determine the impact of this finding.

Air Embolism Detected During Computed Tomography Fluoroscopically Guided Transthoracic Needle Biopsy

Air embolism is a rare but potentially fatal complication of percutaneous needle biopsy of the lung. We report a case of cerebral air embolism which occurred during computed tomography (CT)-guided needle biopsy. Air entering the aorta is depicted on CT-fluoroscopy images of the procedure.

A Case of Gerstmann-Sträussler-Scheinker Syndrome

Gerstmann-Sträussler-Scheinker syndrome (GSS syndrome) is a rare hereditary disorder caused by prion protein gene mutation. We present the case of a 31-year-old man, whose signs and symptoms gradually progressed from loss of attention while driving at onset to headache, dysarthria, night sweat, fatigue, and dysgraphia. Diffusion-weighted imaging (DWI) of the brain after admission showed high signal intensities in the bilateral caudate nuclei, bilateral thalami, and cerebral cortices that suggested transmissible spongiform encephalopathy. The patient was diagnosed with GSS syndrome on genetic study. Magnetic resonance (MR) imaging of the entire period of sickbed showed gradually changing signal intensities and cerebral atrophy. We present a series of images and discuss the reasons for the abnormal intensities in GSS syndrome that vary among reported cases.

A case of testicular malignant lymphoma with extension to the epididymis and spermatic cord

Findings of magnetic resonance imaging (MRI) in a case of testicular lymphoma are presented. The tumor was lower intensity than the normal testis on T2-weighted images. Coronal images clearly showed the tumor extending to the spermatic cord. Compared with seminoma, lymphoma more often invades the epididymis and spermatic cord. MRI is a useful method for differentiating between testicular lymphoma and seminoma because it clearly shows tumor extension to the epididymis and spermatic cord.

Chronic expanding hematoma in the retroperitoneal space: a case report

A case of retroperitoneal chronic expanding hematoma complicated with hydronephrosis, which was difficult to diagnose preoperatively, is reported. The patient was a 70-year-old man. An 18 cm mass was detected in the right retroperitoneal space on abdominal CT screening. There were small calcifications in the periphery of the mass that were strongly enhanced in the delayed phase of dynamic CT. The mass involved the right ureter and iliopsoas muscle, resulting in severe hydronephrosis. The histological diagnosis was chronic expanding hematoma.

[Feasibility of CT attenuation values in the diagnosis of anemia]

PURPOSE

To verify the possible correlation between CT attenuation value and hemoglobin (Hb).

MATERIALS AND METHODS

CT attenuation was evaluated in 113 CT studies. Anemia was defined as an Hb level less than 14 g/dl in males and less than 12 g/dl in females. Hb was compared visually by grading (Grade 1: cardiac muscle density much higher than lumen, Grade 2: cardiac muscle density higher than lumen, Grade 3: cardiac muscle density equal to lumen), and with HU of CT attenuation on unpaired t-test (p<0.01). Correlations were calculated using the linear regression method.

RESULTS

Hb of less than 6 g/dl was found to be Grade 1, while that over 12 g/dl was considered Grade 3 on visual grading. The attenuation numbers of subjects with anemia yielded low values, whereas those of normal subjects were higher. There were significant differences between subjects with anemia and normal subjects (p<0.01). HU versus hemoglobin showed a linear increase, with a correlation coefficient of 0.76.

CONCLUSIONS

This simple, readily available information may provide a valuable adjunct in the interpretation of CT examinations.

[Contrast-enhanced MR venography of the head using magnetization prepared rapid gradient echo imaging: comparison between head and body radiofrequency transmitter coil systems]

PURPOSE

To evaluate the image quality and vascular selectivity of MR venography of the head using an MP-RAGE technique when obtained with a body radiofrequency transmitter coil system.

MATERIALS AND METHODS

A total of 24 patients were imaged with a head or body RF transmission system. Subtraction MRA was processed with 0.1 mmol Gd-DTPA administration, and signal-to-noise ratios of the vascular system were measured. Venous demonstration and selectivity were also assessed.

RESULTS

MP-RAGE MR venography with a body transmission system showed almost the same signal intensity for the venous and arterial systems, resulting in nonspecific vascular demonstration, while the head transmission system showed semi-selective venograms owing to inflow-induced high signal on precontrast images. However, MRA with a body transmission system provided a 1.5- to 2.5-fold higher signal-to-noise ratios based on higher gradient performance and excellent demonstration of the head veins, especially those below the skull base.

CONCLUSION

Although selective venography was difficult, MRA with a body transmission coil provided excellent vascular images of the brain.

[Dual-phase chemical-shift imaging in the detection of diffuse bone metastasis]

Preliminary studies were performed to evaluate the usefulness of lumbar bone marrow MRI using the dual chemical-shift GRE sequence in the detection of diffuse bone metastasis. Two GRE images (TE = 2.3 msec and 4.6 msec) were obtained, and SIR was calculated. SIR was designated as the ratio of in-phase to out-of-phase signal intensity. Among 45 patients with suspicious lumbar bone metastases, diffuse bone metastases were present in 7. Mean SIRs were compared by unpaired t-test. SIRs of diffuse bone metastases had significantly higher signal intensities than those of non-diffuse bone metastases of vertebrae (p < 0.01).

Angiosarcoma of the breast: report of a case and its findings of MRI

A 67-year-old woman with angiosarcoma of the left breast is presented. Physical findings showed a hard mass in the left breast with skin discoloration and erythema. Mammography showed a high density shadow in the mass without microcalcification and spicula. On ultrasonography, a hypoechoic mass with an ill-defined boundary was detected. On MRI, the tumor had low signal intensity on T1-weighted images, and higher signal intensity on T2-weighted images. MRI with Gd-DTPA images showed higher signal intensity on T1-weighted images with relatively lower intensity in the central area of the tumor. The artery supplying the tumor derived from the left inner thoracic artery and was visualized on three-dimensional dynamic MRI angiography. Initially misdiagnosed as inflammatory breast cancer, an arterial injection of CPA (100 mg) and 5-FU (500 mg) had been performed preoperatively. The definitive diagnosis of angiosarcoma was established by intraoperative frozen section examination. She underwent modified radical mastectomy and is now free of recurrence. This case emphasizes the difficulties in the clinical diagnosis of angiosarcoma of the breast.

Histopathological analysis of a bladder cancer stalk observed on MRI

Papillary transitional cell carcinoma of the bladder has a loose connective tissue stalk. For staging of bladder cancer on magnetic resonance imaging (MRI), it is important to clearly separate the cancer from the bladder wall. It is possible to distinguish a stalk from the cancer by the difference of intensity on the using MRI. Sixteen stalks of 20 polypoid bladder tumors on any of the T(2)W(I), dynamic images and delayed enhanced images were demonstrated. Most of the stalks show lower signal intensity than the tumors on T(2)W(I), less enhancement on dynamic images and stronger enhancement on delayed enhanced images. The stalk consisted of fibrous connective tissue, capillary blood vessels, inflammatory cell infiltration and edema. This stalk extended from the bladder wall to the center of the tumor. Some of the superficial muscular bundles were pulled into the stalk. These histopathological findings were compatible with the patterns of signal intensities on MRI. The identification of the stalk of a polypoid tumor may be an important observation to exclude bladder wall invasion by tumor.

[Table-moving contrast-enhanced MR angiography of abdominal aortic aneurysm]

Table-moving contrast-enhanced MR angiography (MRA) was performed in 14 cases of abdominal aortic aneurysm to evaluate its clinical usefulness. In all cases, aneurysms were clearly demonstrated and image quality was clinically acceptable. Findings of reconstructed MRA were highly consistent with those of DSA, and thrombosed areas were confirmed on source images. Main aortic branches including renal arteries, common iliac arteries, and internal and external iliac arteries were readily identified on reconstructed MRA and/or source images. Additional findings such as thoracic aortic aneurysm (n = 1), common iliac aneurysm (n = 6), external iliac aneurysm (n = 1), internal iliac aneurysm (n = 1), femoral arterial obstruction (n = 2), and femoral arterial stenosis (n = 4) were also detected. Although table-moving MRA may have disadvantages like reduced blood signal and limited spatial resolution compared with the conventional contrast-enhanced technique, the images that were obtained provided sufficient contrast and resolution for preoperative evaluation. Because abdominal aortic aneurysm is accompanied by various arterial abnormalities in many of the large arteries, table-moving MRA was considered a suitable technique for comprehensive assessment.

[Bone marrow survey by MRI using a table-moving technique]

The bone marrow of the whole body was imaged by MRI in five normal volunteers. The fast short tau inversion recovery (STIR) sequence and sequential imaging using a moving-table system made sagittal and coronal whole body marrow imaging possible within an examination time of 10 minutes. The images obtained showed high resolution and reflected normal red and yellow marrow distribution in all subjects. Additional abnormalities including humeral bone cyst, hepatic cavernous hemangiomas, and maxillary retention cyst were detected. Fast STIR with the table-moving technique was considered a suitable method for rapid bone marrow survey.

A case of extrahepatic portal vein aneurysm with massive thrombosis: diagnosis with reconstruction images from helical CT scans

A patient with extrahepatic portal vein aneurysm with massive thrombosis, congenital in nature, is reported. Reconstructed images using curved reformation software and three-dimensional images from helical CT were useful to delineate the shape of the portal vein aneurysm and extension of the thrombi.