Evaluation of MR diffusion-weighted imaging in differentiating endometriosis infiltrating the bowel from colorectal carcinoma

Objective

Endometriosis infiltrating the bowel may be difficult to differentiate from colorectal carcinoma in cases that present with non-specific clinical and imaging features. The aim of this study is to assess the value of MR diffusion-weighted imaging (DWI) in differentiating endometriosis infiltrating the bowel from colorectal carcinoma.

Methods

In 66 patients, MR DWI was added to the standard imaging protocol in patients visiting our outdoor MR clinic for the analysis of suspected or known deep infiltrating endometriosis (DIE). In patients diagnosed with DIE infiltrating the bowel on MR imaging, high b-value diffusion-weighted images were qualitatively assessed by two readers in consensus and compared to high b-value diffusion weighted images in 15 patients evaluated for colorectal carcinoma. In addition, ADC values of lesions were calculated, using b-values of 50, 400 and 800 s/mm².

Results

A total of 15 patients were diagnosed with DIE infiltrating the bowel on MR imaging. Endometriosis infiltrating the bowel showed low signal intensity on high b-value diffusion-weighted images in all patients, whereas colorectal carcinoma showed high signal intensity on high b-value diffusion-weighted images in all patients. Mean ADC value in endometriosis infiltrating the bowel (0.80 ± 0.06 × 10⁻³ mm²/s) was significantly lower compared to mean ADC value in colorectal carcinoma (0.86 ± 0.06 × 10⁻³ mm²/s), but with considerable overlap between ADC values.

Conclusion

Only qualitative assessment of MR DWI may be valuable to facilitate differentiation between endometriosis infiltrating the bowel and colorectal carcinoma.     

Feasibility of 3.0T pelvic MR imaging in the evaluation of endometriosis

Introduction

Endometriosis represents an important clinical problem in women of reproductive age with high impact on quality of life, work productivity and health care management. The aim of this study is to define the role of 3 T magnetom system MRI in the evaluation of endometriosis.

Materials and methods

Forty-six women, with transvaginal (TV) ultrasound examination positive for endometriosis, with pelvic pain, or infertile underwent an MR 3.0 T examination with the following protocol: T2 weighted FRFSE HR sequences, T2 weighted FRFSE HR CUBE 3D sequences, T1 w FSE sequences, LAVA-flex sequences. Pelvic anatomy, macroscopic endometriosis implants, deep endometriosis implants, fallopian tube involvement, adhesions presence, fluid effusion in Douglas pouch, uterus and kidney pathologies or anomalies associated and sacral nervous routes were considered by two radiologists in consensus. Laparoscopy was considered the gold standard.

Results

MRI imaging diagnosed deep endometriosis in 22/46 patients, endometriomas not associated to deep implants in 9/46 patients, 15/46 patients resulted negative for endometriosis, 11 of 22 patients with deep endometriosis reported ovarian endometriosis cyst. We obtained high percentages of sensibility (96.97%), specificity (100.00%), VPP (100.00%), VPN (92.86%).

Conclusion

Pelvic MRI performed with 3 T system guarantees high spatial and contrast resolution, providing accurate information about endometriosis implants, with a good pre-surgery mapping of the lesions involving both bowels and bladder surface and recto-uterine ligaments.     

Body diffusion-weighted MR imaging of uterine endometrial cancer: Is it helpful in the detection of cancer in nonenhanced MR imaging?

Objective

In this study, the authors discussed the feasibility and value of diffusion-weighted (DW) MR imaging in the detection of uterine endometrial cancer in addition to conventional nonenhanced MR images.

Methods and materials

DW images of endometrial cancer in 23 patients were examined by using a 1.5-T MR scanner. This study investigated whether or not DW images offer additional incremental value to conventional nonenhanced MR imaging in comparison with histopathological results. Moreover, the apparent diffusion coefficient (ADC) values were measured in the regions of interest within the endometrial cancer and compared with those of normal endometrium and myometrium in 31 volunteers, leiomyoma in 14 patients and adenomyosis in 10 patients. The Wilcoxon rank sum test was used, with a p < 0.05 considered statistically significant.

Results

In 19 of 23 patients, endometrial cancers were detected only on T2-weighted images. In the remaining 4 patients, of whom two had coexisting leiomyoma, no cancer was detected on T2-weighted images. This corresponds to an 83% detection sensitivity for the carcinomas. When DW images and fused DW images/T2-weighted images were used in addition to the T2-weighted images, cancers were identified in 3 of the remaining 4 patients in addition to the 19 patients (overall detection sensitivity of 96%). The mean ADC value of endometrial cancer (n = 22) was (0.97 ± 0.19) × 10⁻³ mm²/s, which was significantly lower than those of the normal endometrium, myometrium, leiomyoma and adenomyosis (p < 0.05).

Conclusion

DW imaging can be helpful in the detection of uterine endometrial cancer in nonenhanced MR imaging.     

Utility of the broccoli sign in the distinction of prolapsed uterine tumor from cervical tumor

Objective

To describe the utility, histopathological basis, and clinical correlates of the broccoli sign.

Methods

The committee on human research approved this HIPAA compliant study and waived written informed consent. Based on the records of the senior author and our multidisciplinary Gynecologic Oncology Tumor Board, we retrospectively identified thirteen women (mean age of 48.8 years; range, 34–74) with a cervical mass seen at MR imaging (n = 13) or CT (n = 5) that demonstrated the previously reported broccoli sign (i.e., a soft tissue stalk connecting the cervical mass to the uterine cavity) on one or other modality. All available clinical, imaging, and histopathological records were reviewed, with particular emphasis on initially suspected diagnosis, final proven diagnosis, and outcome.

Results

Cervical cancer was the initial clinically suspected diagnosis in 6 of 13 patients. Surgical resection demonstrated prolapsed uterine tumor in all patients, consisting of endometrioid adenocarcinoma (n = 7), carcinosarcoma (n = 2), adenosarcoma (n = 1), and leiomyoma (n = 3). Excluding the three patients with leiomyomas, currently, 7 patients with malignant tumors are disease free after a mean interval of 15 months (range, 3–45) and 3 patients have been lost to follow-up.

Conclusion

A stalk connecting an apparent cervical mass seen at CT or MR imaging to the endometrial cavity (“broccoli sign”) favors the diagnosis of a prolapsed uterine tumor; these prolapsed uterine tumors can often be malignant but appear to have a good prognosis.     

Primary adrenal lymphoma: radiological; pathological, clinical correlation

Objective

The purpose of this study was to analyze CT and MR imaging (MRI) manifestation of primary adrenal lymphoma in order to better understand of this rare disease.

Materials and methods

Six patients (4 men, 2 women; median age, 65.5 years) with pathologically proven primary adrenal lymphoma were retrospectively reviewed. Imaging findings (CT&;MRI, n = 3; only CT, n = 3) were analyzed and correlated with clinical and pathologic findings.

Results

All cases were pathologically proven primary adrenal diffuse large B-cell lymphoma with bilateral lesions in 3 cases respectively. Maximum diameters of the 9 lesions were 6.1–14.8 cm, median 10.5 cm. Seven lesions were round, oval or oblong, and 2 lesions irregular. Seven lesions were well-defined and 2 had ill-defined margins. Unenhanced CT density of 9 lesions and MR signal intensity of T1 weighted images of 6 lesions were similar to that of muscle, and all 6 lesions were hyperintense on T2-weighted MR images. Following intravenous injection of contrast media, 6 lesions had mild enhancement and 3 lesions had moderate enhancement on parenchymal phase imaging. Enhancement was homogenous in three, slightly inhomogeneous in four, and heterogeneous in two. Seven lesions, in 5 cases, infiltrated the adjacent tissues or organs in patients with large tumors.

Conclusion

Primary adrenal lymphoma usually manifests as large, well-defined, soft-tissue masses replacing the adrenal gland with homogeneous or slightly inhomogeneous enhancement. Large tumors especially tend to infiltrate adjacent structures.     

Clinical significance of creative 3D-image fusion across multimodalities [PET+CT+MR] based on characteristic coregistration

Objective

To investigate a registration approach for 2-dimension (2D) based on characteristic localization to achieve 3-dimension (3D) fusion from images of PET, CT and MR one by one.

Method

A cubic oriented scheme of“9-point &; 3-plane” for co-registration design was verified to be geometrically practical. After acquisiting DICOM data of PET/CT/MR (directed by radiotracer ¹⁸F-FDG etc.), through 3D reconstruction and virtual dissection, human internal feature points were sorted to combine with preselected external feature points for matching process. By following the procedure of feature extraction and image mapping, “picking points to form planes” and “picking planes for segmentation” were executed. Eventually, image fusion was implemented at real-time workstation mimics based on auto-fuse techniques so called “information exchange” and “signal overlay”.

Result

The 2D and 3D images fused across modalities of [CT + MR], [PET + MR], [PET + CT] and [PET + CT + MR] were tested on data of patients suffered from tumors. Complementary 2D/3D images simultaneously presenting metabolic activities and anatomic structures were created with detectable-rate of 70%, 56%, 54% (or 98%) and 44% with no significant difference for each in statistics.

Conclusion

Currently, based on the condition that there is no complete hybrid detector integrated of triple-module [PET + CT + MR] internationally, this sort of multiple modality fusion is doubtlessly an essential complement for the existing function of single modality imaging.     

MR imaging of hepatic metastasis in patients with malignant melanoma: evaluation of suspected lesions screened at contrast-enhanced CT

Purpose

To evaluate the magnetic resonance (MR) imaging feature of suspected hepatic metastasis in patients with malignant melanoma which showed intermediate findings on screened contrast-enhanced computed tomography (CECT).

Materials and methods

MR imaging was performed in 38 patients (22 men, 16 women; mean age, 58 years) whose CECT findings were intermediate. Hepatic metastases had been diagnosed on MR imaging in 23 of the 38 patients. Verification of hepatic metastasis was made by histological examination: ultrasonographic-guided needle biopsy (n = 3), autopsy (n = 3), and surgical resection (n = 1), or by an obvious progression in number and/or size of the lesions on follow-up MR imaging (n = 24). Two diagnostic radiologists reviewed MR images by consensus. The median follow-up duration was 14.2 months.

Results

Abnormal findings were detected in 31 patients on MR images, and undetected in the remaining seven patients resulting in false-positive on CECT. The mean size of the lesion was 11.0 mm. False-positive results were obtained in two lesions which disappeared on follow-up MR imaging. In six patients, lesions were considered as hepatic cysts on MR images. As a result, a total of 35 hepatic metastases were detected on MR images. Of these, 18 patients demonstrated typical melanotic appearance on MR images which showed shortened T1 and T2 relaxation times, and five patients demonstrated atypical melanotic appearance. In 16 patients, extra-hepatic metastases were also developed.

Conclusion

MR imaging could rule out hepatic metastasis in patients with malignant melanoma which showed intermediate findings on screened CECT, and could detect additional extra-hepatic metastases.     

Peripheral hyperintense pattern on T2-weighted magnetic resonance imaging (MRI) in breast carcinoma: correlation with early peripheral enhancement on dynamic MRI and histopathologic findings

Purpose

To assess the value of magnetic resonance (MR) diffusion‐weighted imaging (DWI) in the evaluation of deep infiltrating endometriosis (DIE).

Materials and Methods

In a prospective single‐center study, DWI was added to the standard MRI protocol in 56 consecutive patients with known or suspected endometriosis. Endometriotic lesions as well as (functional) ovarian cysts were analyzed for location, size, and signal intensity on T1, T2, and DWI. Apparent diffusion coefficient (ADC) values were calculated using b‐values of 50, 400, 800, and 1200 s/mm². Statistical analysis included the Spearman correlation coefficient, Mann–Whitney U, and Kruskal–Wallis tests.

Results

A total of 112 lesions (62 endometrial cysts and 48 DIE) were detected, 60 of which were large enough to analyze. Mean ADC values of endometrial cysts and functional ovarian cysts were 1.11 × 10^?3/mm²/s and 2.14 × 10^?3/mm²/s, respectively. Mean ADC values of DIE retrocervical, infiltrating the colon, and bladder were 0.70 × 10^?3/mm²/s, 0.79 × 10^?3/mm²/s, and 0.76 × 10^?3/mm²/s, respectively. ADC values of DIE did not show a significant difference between varying pelvic locations (P = 0.63).

Conclusion

Results of our study suggest that ADC values of DIE are consistently low, without significant difference between pelvic locations. J. Magn. Reson. Imaging 2010;31:1117–1123. © 2010 Wiley‐Liss, Inc.

     

Solitary necrotic nodule of the liver: MR findings in 33 pathologically proved lesions

Purpose

To determine characteristic magnetic resonance (MR) imaging features of solitary necrotic nodule of the liver.

Materials and methods

MR images features of thirty-two patients (17 men, 15 women; mean age, 43 years; range, 24–76 years) with pathologically proved solitary necrotic nodule of the liver were retrospectively analyzed for number, size, signal intensity features and enhancement patterns.

Results

A total of 33 lesions were identified. The mean diameter was 2.3 cm (range 1.0–4.5 cm). Thirty lesions (90.9%) were 1.0–3.0 cm in diameter and only 3 lesions (9.1%) were larger than 3.0 cm. On T1-weighted images, solitary necrotic nodule of the liver appeared hypointense in 31 lesions (93.9%) and isointense in 2 lesions (6.1%). On T2-weighted images, 12 (36.4%) lesions were hyperintense, 15 (45.4%) were isointense or invisible and 6 (18.2%) were hypointense. After injection of gadopentetate dimeglumine, all lesions were hypointense and none of them showed enhancement.

Conclusion

Solitary necrotic nodule of the liver is usually small with the size not exceed 3.0 cm in diameter. Absence of enhancement on all dynamic phase after gadopentetate dimeglumine administration may be most characteristic feature of solitary necrotic nodule of the liver on MR images, which may help discriminate this entity from metastatic liver tumors and intrahepatic cholangiocarcinoma.     

SSFSE sequence functional MRI of the human cervical spinal cord with complex finger tapping

Purpose

Functional MR imaging of the human cervical spinal cord was carried out on volunteers during alternated rest and a complex finger tapping task, in order to detect image intensity changes arising from neuronal activity.

Methods

Functional MR imaging data using single-shot fast spin-echo sequence (SSFSE) with echo time 42.4 ms on a 1.5 T GE Clinical System were acquired in eight subjects performing a complex finger tapping task. Cervical spinal cord activation was measured both in the sagittal and transverse imaging planes. Postprocessing was performed by AFNI (Analysis of Functional Neuroimages) software system.

Results

Intensity changes (5.5–7.6%) were correlated with the time course of stimulation and were consistently detected in both sagittal and transverse imaging planes of the cervical spinal cord. The activated regions localized to the ipsilateral side of the spinal cord in agreement with the neural anatomy.

Conclusion

Functional MR imaging signals can be reliably detected with finger tapping activity in the human cervical spinal cord using a SSFSE sequence with 42.4 ms echo time. The anatomic location of neural activity correlates with the muscles used in the finger tapping task.     

"Hot cross bun" sign in multiple system atrophy with predominant cerebellar ataxia: a comparison between proton density-weighted imaging and T2-weighted imaging

Objective

To investigate whether proton density-weighted imaging can detect the “hot cross bun” sign in the pons in multiple system atrophy with predominant cerebellar ataxia significantly better than T2-weighted imaging at 3 T.

Methods

Sixteen consecutive patients with multiple system atrophy with predominant cerebellar ataxia according to the Consensus Criteria were reviewed. Axial unenhanced proton density-weighted imaging and T2-weighted imaging were obtained using a dual-echo fast spin-echo sequence at 3 T. Two neuroradiologists independently evaluated visualisation of the abnormal pontine signal using a 4-point visual grade from Grade 0 (no “hot cross bun” sign) to Grade 3 (prominent “hot cross bun” sign on two or more sequential slices). Differences in grade between proton density-weighted imaging and T2-weighted imaging were statistically analysed using the Wilcoxon signed-rank test.

Results

In 11 patients (69%), a higher grade was given for proton density-weighted imaging than T2-weighted imaging. In 1 patient (6%), grades were the same (Grade 3) on both images. In the remaining 4 patients (25%), signal abnormalities were not detected on either image (Grade 0). The “hot cross bun” sign was thus observed significantly better on proton density-weighted imaging than on T2-weighted imaging (P = 0.001).

Conclusions

The “hot cross bun” sign considered diagnostic for multiple system atrophy with predominant cerebellar ataxia is significantly better visualised on proton density-weighted imaging than on T2-weighted imaging at 3 T.     

Nonenhanced ECG-gated time-resolved 4D steady-state free precession (SSFP) MR angiography (MRA) of cerebral arteries: comparison at 1.5T and 3T

Purpose

To compare image quality of nonenhanced time-resolved 4D steady-state free precession MR angiography (4D SSFP MRA) of cerebral arteries at 1.5 T and 3 T.

Materials and methods

12 healthy subjects (mean age 29.4 ± 6.9 years) were studied at both 1.5 T and 3 T. Two different positions of the acquisition slab were evaluated; in one acquisition the imaging slab included the carotid siphon (“S_low”), in the other acquisition the imaging slab was placed superior to the carotid siphon (“S_high”). Subjective image quality of cerebral arteries was assessed independently by two readers on a 4-point scale. Relative Signal-to-Noise-Ratio (SNR) was determined for the M1 segment of the middle cerebral artery.

Results

Subjective image quality of the anterior cerebral artery (segments A1, A2) was significantly higher at 1.5 T as compared to 3 T, while 3 T provided significantly higher image quality for segment P3 of the posterior cerebral artery. For the middle cerebral artery (segments M1–M3), image quality was significantly higher at 1.5 T than at 3 T when the carotid siphon was included in the acquisition slab (“S_low”), while no significant difference was found between 1.5 T and 3 T with “S_high”. Relative SNR was significantly higher at 1.5 T (23.1 ± 5.1) as compared to 3 T (12.1 ± 7.8) for “S_low” and significantly higher at 3 T (29.8 ± 5.9) than at 1.5 T (24.2 ± 3.6) for “S_high”.

Conclusion

Our results indicate that 4D SSFP MRA should preferably be performed at 1.5 T with inclusion of the carotid siphon in the acquisition slab, which might be required for the assessment of intracranial collateral flow.     

Diagnostic value of apparent diffusion coefficients to differentiate benign from malignant vertebral bone marrow lesions

Aim

The aim of this study is to evaluate the value of the apparent diffusion coefficient (ADC) obtained in diffusion-weighted (DW) MR sequences for the differentiation between malignant and benign bone marrow lesions.

Method

Forty-five patients with altered signal intensity vertebral bodies on conventional MR sequences were included. The cause of altered signal intensity was benign osteoporotic collapse in 16, acute neoplastic infiltration in 15, and infectious processes in 14; based on plain-film, CT, bone scintigraphy, conventional MR studies, biopsy or follow-up. All patients underwent isotropic DW MR images (multi-shot EPI, b values of 0 and 500 s/mm²). Signal intensity at DW MR images was evaluated and ADC values were calculated and compared between malignancy, benign edema and infectious spondylitis.

Results

Acute malignant fractures were hyperintense compared to normal vertebral bodies on the diffusion-weighted sequence, except in one patient with sclerotic metastases. Mean ADC value from benign edema (1.9 ± 0.39 × 10⁻³ mm²/s) was significantly (p < 0.0001) higher than untreated metastasic lesions (0.9 ± 1.3 × 10⁻³ mm²/s). Mean ADC value of infectious spondilytis (0.96 ± 0.49 × 10⁻³ mm²/s) was not statistically (p > 0.05) different from untreated metastasic lesions. ADC value was low (0.75 × 10⁻³ mm²/s) in one case of subacute benign fracture.

Conclusions

ADC values are a useful complementary tool to characterize bone marrow lesions, in order to distinguish acute benign fractures from malignant or infectious bone lesions. However, ADC values are not valuable in order to differentiate malignancy from infection.     

Is diffusion-weighted imaging useful in grading and differentiating histopathological subtypes of meningiomas?

Purpose

Meningiomas are mostly benign, however atypical or malignant subtypes with more aggressive clinical course and higher recurrence rates can also be seen. The purpose of this study was to determine whether histopathological subtypes of meningiomas could be assessed preoperatively using apparent diffusion coefficient (ADC) values.

Materials and methods

Conventional magnetic resonance (MR) and diffusion-weighted (DW) imaging of 177 adult patients with pathologically proven meningiomas were retrospectively evaluated. Tumor size and the degree of associated edema were noted. The signal intensity of the lesions on DW imaging was evaluated and graded. Mean ADC values were obtained as the mean of measurements from three regions of interests within the mass. ADC ratios of meningioma/contralateral normal appearing subcortical parietal white matter were also calculated.

Results

The histopathological analysis revealed 135 benign, 37 atypical and 5 malignant lesions. With classification according to the subtype, the mean ADC values and ratios of benign meningiomas were as 0.99 ± 0.12 × 10⁻³ mm²/s and 1.22 ± 0.07, respectively. ADC values for atypical and malignant groups were both 0.84 ± 0.1 × 10⁻³ mm²/s. The ADC ratios were 1.05 ± 0.1 and 0.96 ± 0.2 for atypical and malignant subtypes, respectively. There was no statistically significant difference between the mean ADC ratios of the three subtypes (ANOVA test; P ≥ 0.05). Gender, age of the patients and tumor size showed no statistically significant difference between the different histological groups.

Conclusion

DW MR imaging was not found to have any additional value in determining histological behaviour nor in differentiating histopathological subtypes of meningiomas.     

MRI of fat necrosis of the breast: the "black hole" sign at short tau inversion recovery

Objective

To describe MRI features of fat necrosis of the breast.

Materials and methods

Twenty-five lesions in 16 patients were retrospectively analyzed. MRI was performed due to equivocal findings at conventional imaging after surgical treatment of cancer (n = 14) or during anticoagulant therapy (n = 1), after focal mastitis treated with ductal resection (n = 1). In the 15 patients with previous surgery MRI was performed after a median interval of 24 months, using short tau inversion recovery (STIR) and contrast-enhanced dynamic T1-weighted sequences. Signal-to-noise ratio (SNR) inside the lesion and surrounding healthy fat was calculated on both STIR and unenhanced T1-weighted images. Maximal lesion diameter was measured on STIR images. All lesions had final clinical and imaging assessment in favor of fat necrosis and negative clinical and imaging follow-up (21–40 months; median 24 months).

Results

At STIR sequence, fat necrosis appeared as a “black hole”, being markedly hypointense (median SNR = 29) compared with surrounding fat (median SNR = 95) (P < 0.001), while no significant difference was found at unenhanced T1-weighted sequence. No significant correlation with time from treatment was found. Of 25 lesions, 15 showed ring enhancement, with continuous increase (n = 10), plateau (n = 2), or wash-out curve (n = 3). The 11 enhancing lesions in the 8 patients with previous radiation therapy showed an initial enhancement higher than that of the 4 enhancing lesions in the 2 patients who did not, although the difference was not significant (P = 0.104).

Conclusion

Fat necrosis of the breast exhibits a “black hole” sign on STIR images, allowing for an easier diagnosis in clinical practice.     

Imaging findings of liver resection using a bipolar radiofrequency electrosurgical device--initial observations

Objective

To assess contrast-enhanced US (CEUS), computed tomography (CT) and magnetic resonance (MR) imaging findings and serial changes of the treated area at follow-up in patients who underwent liver resection using a bipolar radiofrequency electrosurgical device.

Methods

Imaging findings of 27 patients with resected hepatocellular carcinomas (HCCs) (n = 24) and metastases (n = 3) (mean size: 2.6 cm), were retrospectively evaluated. Two readers assessed: the (a) presence, (b) thickness, (c) shape and (d) echogenicity (CEUS)/attenuation (CT)/signal intensity (MR imaging) at coagulated site and the (e) presence of residual tumor of the bipolar radiofrequency electrosurgical device resection margin.

Results

Follow-up was performed with either CT (n = 20) or MR imaging (n = 7) and repeated in 16 patients with CT (n = 7), MR imaging (n = 4), or both techniques (n = 5). Four patients also had a single CEUS examination. At first imaging follow-up a peripheral halo was depicted at resection site (100%). A fluid collection within the surgical area was found in 67% of patients. During the following imaging examinations a progressive involution of both findings was observed, respectively, in 81% and 62% of patients. Viable tissue was detected in three patients (11%).

Conclusions

After liver resection with bipolar radiofrequency electrosurgical device successfully ablated tumor is demonstrated at imaging by an unenhancing partial linear peripheral halo, in most cases, surrounding a fluid collection reducing in size during follow-up.     

Comparison of clinical and MR imaging outcomes after uterine fibroid embolization with Bead Block and Embosphere

Purpose

To compare clinical and imaging outcomes after uterine fibroid embolization (UFE) with Embosphere versus Bead Block microspheres.

Materials and methods

Our institutional review board approved this HIPAA-compliant study. We conducted a retrospective review of all consecutive UFEs performed for symptomatic uterine fibroids at our academic institution from 2001 to 2008. UFE was performed using Embosphere (n = 70) or Bead Block (n = 55) microspheres. Patient symptoms and MR images were reviewed before and following UFE. The MR images were analyzed for changes in the size and contrast enhancement of the dominant fibroid and the uterus.

Results

125 patients underwent UFE. Pre-treatment characteristics (patient age, presenting symptoms, fibroid location, and volume of the largest fibroid) were similar across groups. Procedure endpoint (near-stasis, reached in 94% of cases), duration, and sedation medication doses were also similar. Clinical follow-up was available in 69 (55%) patients (mean duration: 13.6 months). Of these, 92% had clinical improvement of their main presenting symptom(s) and 3% developed early menopause. MRI follow-up was available in 105 (84%) patients (mean 7.8 months). Mean volume reduction of the largest fibroid was similar after Embosphere (48%) and Bead Block (53%, p = NS). Residual enhancement ≥5% in the dominant fibroid was similarly uncommon after Bead Block (19%) or Embosphere (16%, p = NS). Mean uterine volume reduction was similar across groups (38%); no myometrial infarction occurred.

Conclusion

This retrospective study showed no superiority of Embosphere over Bead Block microspheres in terms of clinical and imaging outcomes after UFE.     

Tissue characterization of head and neck lesions using diffusion-weighted MR imaging with SPLICE

Purpose

The purpose of this study was to evaluate the usefulness of diffusion-weighted (DW) MR imaging with split acquisition of fast spin-echo signals (SPLICE) in the tissue characterization of head and neck mass lesions.

Patients and methods

DW MR images of 67 head and neck mass lesions were obtained using SPLICE with b-factors of 0 and 771 s/mm². The lesions were classified into three categories: 16 cysts, 32 benign tumors, and 19 malignant tumors. After ADC maps were constructed for all lesions, ADC values were calculated and compared among the three categories.

Results

No case showed severe image distortion on DW MR imaging with SPLICE, and reliable ADC maps and ADC values were obtained in all cases. The mean ADC value of cysts was 2.41 ± 0.48 × 10⁻³ mm²/s, which was significantly higher than that of benign (1.48 ± 0.62 × 10⁻³ mm²/s) and malignant (1.23 ± 0.45 × 10⁻³ mm²/s) tumors (P < 0.001). However, there was no significant difference between the ADC values of benign and malignant tumors (P = 0.246). When an ADC value of 2.10 × 10⁻³ mm²/s or higher was used as the diagnostic criterion for cysts, the sensitivity, specificity, and accuracy were 94%, 88%, and 90%, respectively.

Conclusion

SPLICE was considered a recommended DW MR imaging technique for the head and neck. Although ADC values were useful in differentiating cysts from tumors, they contributed little in predicting malignancy.     

Hepatic lipomas and steatosis: an association beyond chance

Objective

To determine if hepatic lipomas have a higher prevalence of liver steatosis than other benign hepatic lesions.

Materials and methods

Ninety-two benign hepatic lesions were analyzed with magnetic resonance (MR) imaging. There were 6 lipomas and 86 benign non-lipomatous lesions, including 55 hemangiomas, 23 focal nodular hyperplasias (FNH) and 8 adenomas. All studies included a chemical shift T1-weighted sequence (in-phase and opposed-phase) in order to evaluate the presence of steatosis.

Results

A statistically significant relationship (Fischer's Exact Test, p = 0.019) between hepatic lipomas and steatosis was demonstrated. Fifty percent of hepatic lipomas associated steatosis, while this association was present in only 9% of the non-lipomatous lesions.

Conclusion

Lipomas have a significantly greater association with steatosis when compared to nonlipomatous lesions. This relationship may be related to a common insuline resistance mechanism.     

Uterine artery embolisation for symptomatic adenomyosis--mid-term results

Purpose

To evaluate the role of uterine artery embolisation (UAE) in the treatment of adenomyosis.

Materials and methods

27 women with symptomatic adenomyosis diagnosed on magnetic resonance imaging (MRI) underwent UAE between 1998 and 2004. Clinical evaluation using a standardised questionnaire was made at regular intervals after embolisation to assess patient outcome.

Results

The diagnosis of adenomyosis was confirmed histologically by transvaginal biopsy in 5 women. There were 14 women with associated uterine fibroids. Diffuse adenomyosis was identified in 18 women. A focal adenomyoma was present in another 8 women. In 1 patient adenomyosis was not classified. All patients except one underwent bilateral uterine artery embolisation.There was an initial favourable clinical response, with improvement of menorrhagia in 79% (13/16) of patients at 12 months.Follow-up data was available on a total of 14 patients at 2 and 3 years after embolisation. 45.5% (5/11) reported a deterioration in menorrhagia symptoms at 2 years.

Conclusion

UAE for symptomatic adenomyosis is effective in the short-term but there is a high rate of recurrence of clinical symptoms 2 year following treatment.