Primary heart angiosarcoma detected by computed tomography and magnetic resonance imaging

We report a case of primary heart angiosarcoma and its appearance on plain and post-contrast computed tomography and magnetic resonance imaging in 21-year-old woman. The tumour involved the right atrium, expanded superiorly among the superior vena cava, ascending aorta and innominate vein, and infiltrated the pericardium. The tumour was disseminated into lungs, liver and bones at the time of its clinical presentation. Received 24 January 1997; Revision received 13 March 1997; Accepted 28 April 1997     

Evaluation of spinal trauma by multi detector computed tomography and magnetic resonance imaging

Aim of work

The aim of this work is to assess the role of multi-detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in evaluation of spinal trauma.

Patients and methods

Between January 2013 and April 2014, 98 patients (78 males and 20 females) with spinal injuries were investigated by MDCT and MRI. Assessment of the radiological findings of spinal injury was performed and the following were investigated: vertebral compression fractures, bursts and dislocations, posterior element fractures, C1 and C2 lesions, vertebral listhesis, bone marrow edema, spinal canal compression, disk herniation, extradural hematoma, spinal cord contusions, spinal cord swelling and posterior ligamentous complex injuries.

Result

A total of 271 lesions were diagnosed as follows: 217 lesions were diagnosed using MRI alone, 1 54 lesions were diagnosed using MDCT alone and 100 lesions were diagnosed using MRI and MDCT conjointly. By using MRI 117 more lesions were detected than using MDCT. MRI was significantly superior to MDCT in the diagnosis of bone marrow edema, posterior ligamentous complex injuries, disk herniations, spinal canal compressions, and spinal cord contusions and edema. In cervical spine injuries, MRI was useful for the evaluation of the supporting ligaments and the spinal cord after the patient has been stabilized. The average times required to perform CT and MRI were 1.38 ± 19.83 and 2.00 ± 19.58 days, respectively; this difference was significant (p?0.05) according to the Mann–Whitney test.

Conclusion

MRI was significantly superior to MDCT in the diagnosis of bone marrow edema, posterior ligamentous complex injuries, disk herniations, spinal canal compressions, and spinal cord contusions and edema. In cervical spine injuries, MRI was useful for the evaluation of the supporting ligaments and the spinal cord after the patient has been stabilized.MDCT and MRI are complementary to each other in evaluation of spine injuries.     

Ameloblastic carcinoma of the mandible with metastasis to the skull and lung: advanced imaging appearance including computed tomography,magnetic resonance imaging and positron emission tomography computed tomography

Ameloblastic carcinoma is a very rare malignant odontogenic tumour with characteristic histopathological and clinical features, which requires aggressive surgical treatment and surveillance and, therefore, differs from ameloblastoma. Metastasis typically occurs in the lung. Only one patient with metastasis to the skull has previously been described and no prior case reports have presented MRI and positron emission tomography-CT (PET-CT) imaging findings. We describe a case of ameloblastic carcinoma with metastasis to the skull and lung with emphasis on imaging features including MRI and PET-CT.     

Non-cardiac findings on coronary computed tomography and magnetic resonance imaging

Both multislice computed tomography (CT) and magnetic resonance imaging (MRI) are emerging as methods to detect coronary artery stenoses and assess cardiac function and morphology. Non-cardiac structures are also amenable to assessment by these non-invasive tests. We investigated the rate of significant and insignificant non-cardiac findings using CT and MRI. A total of 108 consecutive patients suspected of having coronary artery disease and without contraindications to CT and MRI were included in this study. Significant non-cardiac findings were defined as findings that required additional clinical or radiological follow-up. CT and MR images were read independently in a blinded fashion. CT yielded five significant non-cardiac findings in five patients (5%). These included a pulmonary embolism, large pleural effusions, sarcoid, a large hiatal hernia, and a pulmonary nodule (>1.0 cm). Two of these significant non-cardiac findings were also seen on MRI (pleural effusions and sarcoid, 2%). Insignificant non-cardiac findings were more frequent than significant findings on both CT (n = 11, 10%) and MRI (n = 7, 6%). Incidental non-cardiac findings on CT and MRI of the coronary arteries are common, which is why images should be analyzed by radiologists to ensure that important findings are not missed and unnecessary follow-up examinations are avoided.     

肺静脉变异的MSCT研究

目的:探讨MSCT对肺静脉与左心房连接方式各种变异的显示,为临床提供解剖学信息。方法:收集例行冠状动脉CTA检查且排除影响肺静脉疾病者共712例,其中男449例,女263例;年龄34～82岁,平均59.63岁。以原始横断面CT图像为基础,采用VR、MIP及MPR等后处理方法,观察并统计肺静脉开口数目、副肺静脉及肺静脉共同开口情况,进行分型,并对肺静脉共干、副肺静脉在性别及肺静脉变异左右侧别有无差异进行统计学分析。结果:肺静脉可分为4种类型,标准型最常见,共532例(74.7%);副肺静脉型85例(11.9%),其中左副肺静脉6例,右副肺静脉72例,最上肺静脉7例;肺静脉共同开口型86例(12.1%),其中左侧肺静脉共干76例,右侧肺静脉共干6例,双侧肺静脉共干4例;混合型9例(1.3%)。肺静脉的变异率为25.3%。副肺静脉发生率男性为14.3%,女性11.4%,肺静脉共干发生率男性14.0%,女性12.2%,以上性别差异无统计学意义。肺静脉变异率左侧13.3%(95/712),右侧12.8%(91/712),差异无统计学意义。结论:肺静脉的解剖变异较大,对肺静脉进行合理的分型,有助于肺静脉与左心房关系的解剖学评估,可为临床手术及房颤射频消融治疗提供有价值的肺静脉解剖路线图。     

Computed tomography and magnetic resonance imaging evaluation of patellofemoral instability

Malalignment and tracking abnormalities of the patellofemoral joint are common causes of anterior knee pain,which are often difficult to evaluate clinically. Conventional radiography, as well as the cross-sectional imaging modalities of computed tomography (CT) and magnetic resonance imaging (MRI) are useful tools for both detecting and quantifying these abnormalities. Acute transient dislocation of the patella, on the other hand, is a relatively uncommon injury accounting for only 2% to 3% of all acute injuries of the knee, and can also be a difficult diagnosis to establish on the basis of history and physical findings alone. MRI is a sensitive, noninvasive method for detecting prior acute transient dislocation of the patella. This article begins by describing the role of CT and MRI as it pertains to the detection of abnormal patellofemoral tracking. Both static and dynamic techniques are described along with the standard criteria used to establish and quantify patellofemoral malalignment abnormalities. Next, the constellation of MRI findings most commonly encountered after acute transient dislocation of the patella are described. These findings include a typical bone bruise pattern involving the anterolateral aspect of the lateral femoral condyle and inferomedial patella, hemarthrosis, and injury to the medial soft-tissue restraints (especially the medial patellofemoral ligament). After transient dislocation of the patella, patients with significant osteochondral injury or disruption of the medial soft-tissue restraints may benefit from surgical repair. The role of MRI in preoperative planning is discussed as it relates to the detection of osteochondral injuries as well as injury to the medial soft-tissue restraints.     

Assessment of regional left ventricular function with multidetector-row computed tomography versus magnetic resonance imaging

This study compares quantitative and qualitative information on global and regional left ventricular (LV) function obtained with multidetector-row computed tomography (MDCT) with that obtained with magnetic resonance imaging (MRI) in patients with a high prevalence of LV wall motion abnormalities. Thirty patients (19 male, 63.7+/-15.1 years) with myocardial infarction (n=12), coronary artery disease (n=9), arrhythmogenic right ventricular cardiomyopathy (n=6), and dilation cardiomyopathy (n=3) were included. Segmental LV wall motion (LV-WM) was assessed using a 4-point scale. Wall thickness measurements were calculated in diastolic and systolic short axis images. Two hundred and fifty-two out of 266 (94.7%) normal and 189 out of 214 (88.3%) segments with decreased wall motion were correctly identified by MDCT, yielding a sensitivity of 88% and specificity of 95% for identification of wall motion abnormalities. LV-WM scores were identical in 86.7% of 480 segments (kappa=0.809). MDCT had a tendency to underestimate the degree of wall motion impairment. Interobserver agreement was lower in MDCT (66.5%) than in MRI (89.1%; p<0.01). Normokinetic segments are reliably identified with MDCT. Sensitivity for detection and accurate classification of LV wall motion abnormalities need to be improved. Better temporal resolution of the CT system seems to be the most important factor for enhancing MDCT performance.     

Pulmonary vein inflow artifact reduction for free‐breathing left atrium late gadolinium enhancement

Two‐dimensional “pencil‐beam” navigator, placed on the right hemidiaphragm, is used for free‐breathing late gadolinium enhancement of the left atrium in patients with atrial fibrillation. The pencil‐beam navigator creates an inflow artifact in the right pulmonary veins and atrial wall that may obscure local pulmonary vein and left atrium scars. To reduce this artifact, we propose a large slab right hemidiaphragm projection navigator that measures the respiratory motion while reducing the associated inflow artifact. Eighteen subjects underwent pulmonary vein late gadolinium enhancement using the pencil‐beam and projection navigator. Subjective inflow and respiratory motion artifact scores (1 = severe, 2 = moderate, 3 = mild, and 4 = none) from two blinded readers were compared. The artifact scores were 3.8 ± 0.4 and 2.1 ± 0.7 for the projection and pencil‐beam navigators, respectively (P < 0.001). Respiratory motion artifact scores were similar between the two techniques (3.0 ± 0.5 vs. 3.1 ± 0.5 for projection vs. pencil‐beam navigator). The proposed method greatly reduces the inflow artifact in free‐breathing pulmonary vein late gadolinium enhancement while allowing adequate respiratory motion compensation. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.     

Diagnostic performance of magnetic resonance imaging for detecting osseous abnormalities of the temporomandibular joint and its correlation with cone beam computed tomography

Objective

With cone beam CT (CBCT) as the reference standard, the objective of this study was to determine the diagnostic accuracy of MRI for assessing osseous abnormalities of the temporomandibular joint (TMJ).

Methods

106 TMJs from 55 patients with temporomandibular disorder were examined by CBCT and MRI. CBCT images were evaluated by two experienced oral radiologists with regard to the presence or absence of each of the following eight types of osseous abnormalities: Type 1, destructive and erosive osseous changes of the condyle; Type 2, flattening of the articular surface of the condyle; Type 3, deformity of the condyle; Type 4, sclerosis of the condyle; Type 5, osteophyte formation; Type 6, ankylosis; Type 7, erosion of the articular fossa and/or eminence; and Type 8, sclerosis of the articular fossa and/or eminence. For detection of these osseous abnormalities by MRI, proton density-weighted images and T₂ weighted images were evaluated independently by three observers. Using CBCT findings as the reference standard, the diagnostic performance of MRI for detecting various types of osseous abnormalities was evaluated by calculating its sensitivity and specificity.

Results

Out of 106 joints, CBCT revealed Types 1, 2, 3, 4, 5, 6, 7 and 8 abnormalities in 25, 19, 26, 20, 14, 5, 19 and 22 joints, respectively. The mean sensitivities of MRI among the three observers for detecting Types 1, 2, 3, 4, 5, 6, 7 and 8 abnormalities were 61%, 30%, 82%, 40%, 48%, 34%, 61% and 41%, respectively, whereas the mean specificities were 86%, 92%, 91%, 95%, 84%, 98%, 89% and 91%, respectively.

Conclusions

Although high specificity (84–98%) was obtained with MRI, this modality showed relatively low sensitivity (30–82%) for detecting osseous abnormalities of the TMJ. The value of MRI for the detection of TMJ osseous abnormalities is considered to be limited.     

Coronary anomalies assessed by whole‐heart isotropic 3D magnetic resonance imaging for cardiac morphology in congenital heart disease

Purpose

To determine the value of whole‐heart three‐dimensional magnetic resonance imaging (MRI) for coronary artery imaging in children/adolescents with congenital heart disease (CHD).

Materials and Methods

Forty children/adolescents (median age: 14 years, range 2.6–25.8) with CHD underwent free‐breathing navigator‐gated isotropic three‐dimensional steady‐state free‐precession (3D‐SSFP) MRI for cardiac morphology. Two observers independently evaluated visibility of origin, course, vessel lengths, image quality (IQ), and contrast between coronary lumen and myocardium. A subgroup was compared with cardiac catheter.

Results

The total scan time was 6.3 ± 3.2 minutes (mean ± SD, at mean heart rate 76 ± 15/min). The mean vessel length for right coronary artery (RCA) by observer 1 was 97 ± 43 mm (observer 2: 94 ± 37 mm), for left main and anterior descending artery (LM/LAD) 91 ± 40 mm (observer 2: 90 ± 40 mm), and for left circumflex artery (LCX) 64 ± 28mm (observer 2: 66 ± 28 mm). The mean vessel contrast was 0.34 ± 0.05 (range: 0.23–0.45; maximum = 1, minimum = 0). On a 4‐level score (1 = nondiagnostic, 4 = excellent), mean IQ scores ranged between 2.3–2.9 (±0.8–1.0). Both observers agreed on the presence/proximal course of RCA in 40/40, LM/LAD in 38/40, and LCX in 36/40 patients. There was complete agreement with invasive coronary angiography available in 12/40 patients (six anomalies).

Conclusion

Isotropic whole‐heart 3D‐MRI for cardiac morphology allows reliable discrimination between normal and abnormal coronary anatomy in children/adolescents with CHD. J. Magn. Reson. Imaging 2009;29:320–327. © 2009 Wiley‐Liss, Inc.     

Nonclinical factors associated with primary care physicians’ ordering patterns of magnetic resonance imaging/computed tomography for headache

RATIONALE AND OBJECTIVES: The purpose of ordering an imaging test for headache, which is one of the most common reasons for patient consultation with a primary care physician (PCP), include medical indications as well as patient anxiety and medico-legal concerns. The impact of nonclinical factors on PCPs' ordering patterns of magnetic resonance imaging/computed tomography for patients presenting with a headache was examined. MATERIALS AND METHODS: A retrospective record review of all patients treated for headache as their primary complaint by a PCP from a multispecialty group practice associated with an 180,000-member Health Maintenance Organization during calendar year 2000 was examined. The practice included 18 clinics. Logistic regression was used to estimate the association between physician ordering patterns of imaging tests and patient, physician, and clinic setting characteristics. RESULTS: Of the total study subjects (n = 4,372), a magnetic resonance imaging/computed tomography imaging test was ordered for 5.3%. At their first encounter, patient's gender, site of care, and insurance status under the health care system's Health Maintenance Organization had statistically significant associations with the likelihood of imaging test orders. Female physicians were less likely to order an imaging test (OR = 0.65; 95% confidence interval, 0.39-1.08). For subsequent encounters, however, site of care was the only nonclinical factor that had a consistent association with the likelihood of having a magnetic resonance imaging/computed tomography ordered. CONCLUSION: These data show that a number of nonclinical factors may have been associated with having an imaging test ordered by a PCP when patients presented with a headache. These factors were more significant when the patient was being seen for the first time with this complaint.     

Computed tomography and magnetic resonance imaging findings in cerebral hydatid disease

Purpose: The purpose of this study was to describe the discriminative computed tomography (CT) and magnetic resonance imaging (MRI) features of cerebral hydatid disease.Methods: The CT and MRI findings of four cases of surgically proven cerebral hydatid cysts were retrospectively reviewed. Results: CT demonstrated well-defined cystic lesions with no perilesional oedema and no contrast enhancement in all cases except one recurrent disease that showed both peripheral oedema and rim enhancement. MR images revealed well-defined cystic lesions with a quite clear rim that showed relative hypointensity limited to some aspects of the cyst walls on T2-weighted images. The cysts were spherical and obvious mass effect was observed on both CT and MR examinations. Conclusions: Although the cystic nature of intracranial hydatid disease could be equally well demonstrated on CT and MR examinations, CT is superior in detecting calcification of the cyst wall or septa, when present, and MR is better in demonstrating cyst capsule, detecting multiplicity and defining the anatomic relationship of the lesion with the adjacent structures and helps in surgical planning.     

Postmortem computed tomography and magnetic resonance imaging in a case of terminal-stage small cell lung cancer: an experience of autopsy imaging in tumor-related death

We report a case of terminal-stage small-cell lung cancer with multiple metastases in which postmortem computed tomography and magnetic resonance imaging (collectively called “autopsy imaging”) were performed and correlated with conventional autopsy findings. In this case, autopsy imaging provided contemporaneous data that supported conventional autopsy findings. Autopsy imaging revealed the process of primary tumor growth, changes in metastatic lesions, and occurrences of new metastases in the terminal stage and made it easier to understand the clinical course of the patient. The usefulness of autopsy imaging after traumatic death, sudden death from natural causes, or congenital anomaly has been reported. Here, we attempted a preliminary study of its use in the detection of death due to tumor. Our results indicated that autopsy imaging provides useful information in cancer-related death and may be an alternative when conventional autopsy cannot be performed.     

Evaluation of the acute effects of distal coronary microembolization using multidetector computed tomography and magnetic resonance imaging

The purpose of this study was to test the potential of clinical imaging modalities, 64-slice multidetector computed tomography (MDCT) and 1.5T magnetic resonance imaging (MRI) for qualitative and quantitative evaluation of acute microinfarcts and to determine the effects of <120 μm microemboli on left ventricular function, perfusion, cardiac injury biomarkers, arrhythmia, and cellular and vascular structures. Under X-ray fluoroscopy, 40-120 μm (16 mm(3) ) microemboli were delivered to embolize the left anterior descending (LAD) coronary artery of nine pigs. MDCT/MRI were performed at 72 h in a single session. Microinfarcts were visible in six of nine animals on delayed contrast-enhanced MDCT/MR images but measurable in all animals using semiautomated threshold methods. Other MDCT and MRI sequences demonstrated decline in left ventricular ejection fraction, regional strain and perfusion in visible and invisible microinfarcted regions. Microemboli caused significant elevation in cardiac injury enzymes and arrhythmias. Various sizes of microinfarcts appeared microscopically as distinct aggregates of macrophages replacing myocardium. Semiautomated threshold methods are necessary to measure and confirm/deny the presence of myocardial microinfarcts. This study offers support for alternative applications of MDCT/MRI in assessing clinical cases in which microemboli <120 μm escape protective devices during percutaneous coronary interventions. Although microembolization resulted in no mortality, it caused left ventricular dysfunction, perfusion deficit, cellular damage increase in cardiac injury enzymes, and arrhythmias.     

Dumbbell-shaped thoracic hibernoma: computed tomography and magnetic resonance imaging findings

Hibernoma is an uncommon, benign soft tissue tumor that arises in brown adipose tissue. The computed tomography (CT) and magnetic resonance imaging (MRI) findings of hibernomas are similar to those of well-differentiated liposarcoma or angiolipoma. We report the unique appearance of a rare thoracic wall hibernoma, which appeared as a dumbbell-shaped lipomatous tumor across an intercostal region. A dynamic contrast-enhanced study on MRI revealed early enhancement, which corresponded to the branching low-signal intensity on T2-weighted images of the mass.     

Ultrasonography, computed tomography and magnetic resonance imaging for diagnosis of ovarian carcinoma

Our objective was to compare US, CT, and MR imaging in differentiation of malignant from benign ovarian tumors. Through an electronic literature search and manual review of bibliographies (January 1990 to June 2006), relevant studies on the diagnostic performance of US, CT, and MR imaging in the differentiation between benign and malignant ovarian tumours were identified. Sixty-nine articles were included, yielding 143 studies. Data on the accuracy of the different imaging modalities were analyzed and compared by constructing summary receiver-operating characteristic (ROC) curves. Our results suggest that US techniques seems to be similar with CT and MRI in differentiation of malignant from benign ovarian tumors. The results also revealed that color Doppler flow imaging alone is significantly inferior to combined US techniques, morphologic assessment alone and contrast enhanced US in diagnosis of ovarian cancer. In conclusion, US morphologic assessment still is the most important and common modality in detect ovarian cancer.     

Diagnosis of colorectal hepatic metastases: Contrast-enhanced ultrasonography versus contrast-enhanced computed tomography versus superparamagnetic iron oxide-enhanced magnetic resonance imaging with diffusion-weighted imaging

Purpose:

To create a reliable rat model with small renal cortical scars and evaluate the accuracy and sensitivity of dynamic contrast‐enhanced MRI in detecting the kinds of lesions that are associated with reflux nephropathy.

Materials and Methods:

In 16 rats, three unilateral renal cortical lesions were created using either electrocautery or pure alcohol with the contralateral kidney serving as control. MRI on a 1.5 Tesla GE Signa was performed 10–14 days after surgery. After bolus injection of 0.2 mM/Kg Gd‐DTPA, sequential MRI acquisitions were performed using a 4‐inch quadrature birdcage coil. Renal and scar volumes and pathology were compared after scanning and killing.

Results:

Of the 48 points of injury, 40 (83%) in the 16 rats were detected grossly. Under microscopy, 36 injuries (75%) were detected on mid‐kidney cross‐sections. The average lesion was 4.2 mm³ corresponding to 0.5% of the kidney volume. Using pathological findings as the gold standard, the sensitivity and specificity of scar detection using MRI was 69% and 93%, respectively.

Conclusion:

A rat model was created to demonstrate the sensitivity of dynamic contrast‐enhanced MRI for detecting renal scars. Alcohol and electrocautery created reliable renal scars that were confirmed pathologically. MRI detected these lesions that averaged 4.2 mm³ (0.5% total renal volume) with sensitivity and specificity of 69% and 93%, respectively. J. Magn. Reson. Imaging 2010;31:1132–1136. © 2010 Wiley‐Liss, Inc.     

Cardiovascular magnetic resonance imaging for accurate sizing of the left atrium: predictability of pulmonary vein isolation success in patients with atrial fibrillation

Purpose

To prospectively determine the most reproducible approach for left‐atrial size assessment using cardiovascular magnetic resonance (CMR) imaging in patients with atrial fibrillation and its value for prediction of pulmonary vein isolation (PVI) treatment success.

Materials and Methods

Eighty patients underwent CMR imaging prior to PVI; the CMR examination included standard cine sequences, a multislice cine sequence in 4‐chamber orientation with full left‐atrial coverage, and a contrast‐enhanced MR angiography of the left atrium. Left‐atrial size was determined as: diameter, area, volume segmented from angiography, and diastolic/systolic volumes from cine imaging (Simpson's rule). All measurements were carried out by two independent observers and repeated by one observer to assess inter‐ and intrareader variability. Treatment success was defined as persisting sinus rhythm after PVI (follow‐up period 12.6 ± 6.6 months).

Results

All left‐atrial measurements showed substantial intrareader agreement. Interreader agreement was substantial for diastolic/systolic left‐atrial volumes only. Calculated bias was found to be minimal (0.1%–4.9%). Predictability of PVI treatment success was best using cine volumetric measurements (cutoff value for diastolic volume, 112 mL) yielding a sensitivity and specificity of 80% and 70%, respectively.

Conclusion

Left‐atrial volumetry based on cine imaging represented the most reproducible approach to determine left‐atrial size. PVI success was predicted best using cine volumetry. J. Magn. Reson. Imaging 2011;33:455–463. © 2011 Wiley‐Liss, Inc.     

MR imaging and computed tomography in patients with rectal tumours clinically judged as locally advanced

AIM: To compare magnetic resonance (MR) imaging and computed tomography (CT) in the local staging of locally advanced rectal tumours. MATERIALS AND METHODS: Sixteen consecutive patients who, after pre-operative radio-chemotherapy (RCT), had surgery for rectal tumours clinically judged as extending into neighbouring tissues in the pelvis, were examined using MR and CT before and after treatment. The examinations were reviewed by four radiologists. The relation of the tumours to 14 different anatomic structures in the pelvis in a total of 50 examinations was studied. The results were compared to surgical and histopathological findings. RESULTS: Seven patients had tumour infiltration of adjacent organs in the pelvis at surgery, the most common being the urinary bladder, prostate, uterus and small bowel. MR predicted involvement of the urinary bladder and the uterus better than CT. However, there were more false positive findings on MR than on CT compared to surgical and histopathological findings. CONCLUSION: For staging of advanced rectal cancers, the overall results were not significantly better for MR than CT. If involvement of the urinary bladder and the uterus cannot be ruled out using CT, MR is advocated due to its higher soft tissue contrast resolution and multi-planar capability.