Ovarian cysts on prenatal MRI

Objective

Ovarian cysts are the most frequently encountered intra-abdominal masses in females in utero. They may, at times, require perinatal intervention. Using magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US) in prenatal diagnosis, we sought to demonstrate the ability to visualize ovarian cysts on prenatal MRI.

Materials and methods

This retrospective study included 17 fetal MRI scans from 16 female fetuses (23–37 gestational weeks) with an MRI diagnosis of ovarian cysts after suspicious US findings. A multiplanar MRI protocol was applied to image and to characterize the cysts. The US and MRI findings were compared, and the prenatal findings were compared with postnatal imaging findings or histopathology.

Results

Simple ovarian cysts were found in 10/16 cases and complex cysts in 7/16 cases, including one case with both. In 11/16 (69%) cases, US and MRI diagnoses were in agreement, and, in 5/16 (31%) cases, MRI specified or expanded the US diagnosis. In 6/16 cases, postnatal US showed that the cysts spontaneously resolved or decreased in size, and in 1/16 cases, postnatal imaging confirmed a hemorrhagic cyst. In 4/16 cases, the prenatal diagnoses were confirmed by surgery/histopathology, and for the rest, postnatal correlation was not available.

Conclusion

Our results illustrate the MRI visualization of ovarian cysts in utero. In most cases, MRI will confirm the US diagnosis. In certain cases, MRI may provide further diagnostic information, additional to US, which is the standard technique for diagnosis, monitoring, and treatment planning.     

The role of MRI in the diagnosis of endometriosis

Aim

The aim of this study is to evaluate the accuracy of the magnetic resonance imaging in diagnosis of endometriosis especially in non-apparent types as tubal and cul de sac endometriosis.

Patients and methods

MRI obtained between January 2007 and June 2009 for 34 premenopausal women complaining of dysmenorrhea, menorrhagia and infertility and the diagnosis of endometriosis were included in the differential diagnosis. T1 weighted fat saturated and T2 weighted images were done for every patient, we evaluated the MR images for the presence of T1 bright signal suggesting endometriosis. Transvaginal US was performed in two perpendicular planes for the detection of focal areas with ill defined borders or abnormal echo texture. Suspicious cases which become negative by laparoscopy were excluded from the study.

Results

MRI diagnosed endometriosis in the uterus in 18 patients, ovarian endometriosis in 13 patients, tubal in two patients, and cul de sac in one patient.

Conclusion

It is concluded that MRI is superior in the diagnosis of endometriosis than transvaginal ultrasound.     

Enhancement pattern of small hepatocellular carcinoma (HCC) at contrast-enhanced US (CEUS), MDCT, and MRI: intermodality agreement and comparison of diagnostic sensitivity between 2005 and 2010 American Association for the Study of Liver Diseases (AASLD) guidelines

Objective

To evaluate agreement between contrast-enhanced ultrasound (CEUS), multi-detector row computed tomography (MDCT) and magnetic resonance imaging (MRI) for the assessment of typical and atypical enhancement patterns of small hepatocellular carcinoma (HCC); and to compare diagnostic sensitivity of 2005 and 2010 American Association for the Study of Liver Diseases (AASLD) guidelines.

Materials and methods

Between January 2008 and December 2009, we included cirrhotic patients with newly diagnosed 10–20 mm HCC imaged at two contrast-enhanced imaging techniques among CEUS, MDCT, and MRI. Dynamic studies were reviewed by two radiologists to assess enhancement pattern. Percentage of cases with concordant findings and Cohen coefficient (k) were calculated. McNemar's test was used to compare sensitivity between 2005 and 2010 AASLD guidelines.

Results

There were 91 patients (69 M; 22 F; mean age, 68 years) with 96 HCCs, studied with a combination of CEUS and MDCT (n = 59), CEUS and MRI (n = 26), or MDCT and MRI (n = 11). Intermodality agreement for assessment of tumor enhancement pattern was 67% (k = 0.294, P = 0.001). Typical enhancement pattern was detected coincidentally at two imaging modalities in 50 (52%) HCCs. Sensitivity for the diagnosis of HCC increased significantly using the 2010 AASLD (81/96 (84%) vs. 50/96 (52%), P < 0.001).

Conclusions

Agreement between two imaging modalities for the detection of typical tumor enhancement pattern was reached in 52% of cases. The 2010 AASLD guidelines significantly increased the sensitivity for the diagnosis of HCC.     

Prevalence of venous sinus stenosis in Pseudotumor cerebri (PTC) using digital subtraction angiography (DSA)

Objectives

To study the prevalence of intracranial venous stenosis in Pseudotumor cerebri patients.

Patients and methods

Thirty patients were diagnosed having PTC according to Dandy criteria. All underwent general and neurological assessment. Radiological assessment included CT scan brain ±MRI brain without contrast, MRV. All underwent digital subtraction angiography (DSA) (venous phase) to confirm the validity of filling gaps seen at the level of MRV.

Results

MRV brain showed that 24 patients (80%) showed filling gaps. Digital subtraction cerebral angiography (venous phase) showed 9 patients (30%) had stenosis in their dural sinuses. MRV showed to be a good screening tool since it had 100% sensitivity and negative predictive value. However, since it has a moderate specificity (62%) with a positive predictive value (PPV) of only 35%, then lesions detected should be confirmed with digital subtraction cerebral angiography (venous phase) particularly those involving the transverse and sigmoid sinus.

Conclusion

Studying the intracranial venous system in patients with PTC is an important step in understanding the pathophysiology of the disease. Detection of venous sinus stenosis opens the way to a novel therapeutic option for refractory patients like venous sinus stenting.     

Comparison of the accuracy of subtraction CT angiography performed on 320-detector row volume CT with conventional CT angiography for diagnosis of intracranial aneurysms

Objective

The accuracy of diagnosis of intracranial aneurysms by subtraction computed tomography angiography (CTA) was compared with conventional non-subtracted CTA and with digital subtraction angiography (DSA).

Methods

56 patients with spontaneous subarachnoid hemorrhage (SAH) and suspected intracranial aneurysms were evaluated from September 2009 to January 2010. All underwent 320-detector row volume CT-CTA examinations. Non-contrast CT of each patient's head with the same scan range was performed before the routine CTA scan as the mask image for subtraction. The subtraction CTA volume data was obtained by subtracting the mask image volume data from the conventional non-subtracted CTA volume data. Subtraction and conventional CTA volume data were transmitted to a VOXAR workstation and two physicians with experience in diagnostic imaging of the nervous system independently carried out image post-processing and judged the results. Neurosurgeons performed endovascular treatment or surgical clipping based on information available through the CTA alone.

Results

In 42 patients, 51 aneurysms were detected by DSA. On a per-aneurysm basis, the diagnostic sensitivity of subtraction CTA was 98.9% for physician 1 and 100% for physician 2. The sensitivity of conventional CTA was 93.7% for physician 1 and 92.6% for physician 2. There was excellent inter-observer agreement (κ = 0.84, 95% confidence interval 0.82–0.85). The overall sensitivity, specificity, positive predictive and negative predictive values of subtraction CTA were all 100%. The overall sensitivity, specificity, positive predictive and negative predictive values of non-subtracted CTA were 94%, 100%, 100% and 76%, respectively. Therapeutic decisions could be made for all 42 patients based on subtraction CTA images, whereas conventional non-subtracted CTA provided sufficient information to make therapeutic decisions for only 35 patients.

Conclusion

Conventional CTA has lower sensitivity for the detection of very small aneurysms and aneurysms adjacent to the skull when compared to subtraction CTA. Subtraction CTA performed on a 320-detector row volume CT is an accurate diagnostic tool that provides data equivalent to that obtained with three-dimensional-DSA for the detection of intracranial aneurysms.     

Ovarian fibromas: MR imaging findings with emphasis on intratumoral cyst formation

Purpose

The purpose of this study was to assess MR imaging findings of ovarian fibromas with emphasis on intratumoral cyst formation.

Materials and methods

MR images with a 1.5-T unit obtained in 17 consecutive patients (age range, 18–87 years; mean age, 58 years) with 17 histologically proven ovarian fibromas were retrospectively reviewed for the size, configuration, signal intensity of solid components, and presence of cystic degeneration and edema within tumor. Size, number, and location of intratumoral cysts were also assessed.

Results

The maximum diameter of tumors ranged from 3.3 to 19.1 cm (mean, 10.9 cm). Seven (41%) tumors were multinodular. On T2-weighted images, solid components of tumors were heterogeneously mixed hypo- and hyperintensity in 16 (94%) tumors. Nine (53%) tumors demonstrated cysts and 16 (94%) demonstrated edema within tumor. The maximum diameter of the largest cysts ranged from 1.0 to 13.2 cm (mean, 6.4 cm), and the number of cysts per tumor ranged from 1 to 60 (mean, 15.6). Of the nine tumors with cystic formation, the predominant location of the cysts was peripheral in five (56%), exophytic in two (22%), central (11%) in one, and diffuse in one (11%).

Conclusion

Peripheral or exophytic cyst formation may be characteristic MR imaging features with ovarian fibromas.     

Role of diffusion-weighted MR imaging in discrimination between the intracranial cystic masses

Objective

Discriminating pyogenic brain abscesses from cystic or necrotic tumors is sometimes difficult with CT or conventional MR imaging. Diffusion MR imaging is a valuable diagnostic test in cases of intracranial cystic masses.

Methods

This work was conducted from July 2008 to June 2013 on 90 patients; 43 males and 47 females. Their ages range from 5 to 70 years. All patients were subjected to routine MRI examination and diffusion weighted imaging using 1.5 T MRI scanner. Gadolinium was given to some cases on routine MRI. Diffusion weighted imaging was performed with a single-shot spin-echo echo-planar pulse sequence (b = 0–1000 s/mm²). The apparent diffusion coefficient values and ratio were measured.

Results and conclusions

Patients in this study were categorized into three main groups; first group is brain abscesses (36 cases), 91.6% of them showed restricted diffusion, second group is malignant cystic or necrotic brain tumors, 28 cases of high grade necrotic glioma, 60.7% of them are free diffusion, and third group is benign cystic masses, arachnoid and epidermiod cysts (11 cases); all arachnoid cysts are free diffusion. From these results diffusion-weighted imaging is playing an important role in discrimination of cystic intracranial masses.     

Fate of hypointense lesions on Gd-EOB-DTPA-enhanced magnetic resonance imaging

Purpose

To investigate the natural outcome and clinical implication of hypointense lesions in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI.

Materials and methods

Forty patients underwent Gd-EOB-DTPA-enhanced MRI for preoperative evaluation of HCC. Hypointense lesions in the hepatobiliary phase that were hypovascular 5 mm of more were extracted for follow-up. We performed a longitudinal study retrospectively for these lesions regardless of whether classical HCC developed or emerged in a different area from that of the lesions being followed.

Results

Thirty one patients displayed 130 hypointense lesions on MRI and only nine showed no hypointense lesions. In total, 17 (13.1%) of 130 hypointense lesions on MRI developed into classical HCC. The cumulative rates for these lesions to develop into classical HCC were 3.2% at 1 year, 11.1% at 2 years and 15.9% at 3 years. The total occurrence rates of classical HCC (25.8% at 1 year, 52.6% at 2 years and 76.4% at 3 years) were higher compared to those regarding only occurrence of classical HCC from hypointense lesions on MRI (10.0% at 1 year, 35.6% at 2 years and 44.6% at 3 years), although no significant difference was observed (p = 0.073).

Conclusions

Hypointense lesions that are detected in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI have some malignant potential, although treating these lesions aggressively in patients who already have HCC may be too severe.     

Value of dynamic multidetector CT in different grades of hepatocellular carcinoma

Purpose

To evaluate dynamic multidetector CT (MDCT) in assessment of grades of hepatocellular carcinoma (HCC).

Patients and methods

Forty patients of HCC were assessed. Enhancement patterns were correlated with pathological grades.

Results

Three enhancement patterns were:

1.

Hyperattenuating lesions in portal venous phase.

2.

Hypoattenuating lesions in all phases.

3.

Hyperattenuating lesions in arterial phase.

Conclusion

Arterial and portal biphasic imaging was the most informative in assessment of tumor grades. High grade lesions were hyperattenuating in arterial phase.At initial evaluation, triphasic imaging is advisable, while in diagnosed cases and on follow up, biphasic imaging could be satisfactory.     

Postinterventional MRI findings following MRI-guided laser ablation of osteoid osteoma

Objective

To evaluate postinterventional magnetic resonance imaging (MRI) characteristics following MRI-guided laser ablation of osteoid osteoma (OO).

Materials and methods

35 patients treated with MRI-guided laser ablation underwent follow-up MRI immediately after the procedure, after 3, 6, 12, 24, 36, and up to 48 months. The imaging protocol included multiplanar fat-saturated T2w TSE, unenhanced and contrast-enhanced T1w SE, and subtraction images. MR images were reviewed regarding the appearance and size of treated areas, and presence of periablation bone and soft tissue changes. Imaging was correlated with clinical status.

Results

Mean follow-up time was 13.6 months. 28/35 patients (80%) showed a postinterventional “target-sign” appearance consisting of a fibrovascular rim zone and a necrotic core area. After an initial increase in total lesion diameter after 3 months, a subsequent progressive inward remodeling process of the zonal compartments was observed for up to 24 months. Periablation bone and soft tissue changes showed a constant decrease over time. MR findings correlated well with the clinical status. Clinical success was achieved in 32/35 (91%).

Conclusions

Evaluation of long-term follow-up MRI after laser ablation of OO identified typical postinterventional changes and thus may contribute to the interpretation of therapeutic success and residual or recurrent OO in suspected cases.     

MRI diffusion-weighted imaging in intracranial hemorrhage (ICH)

Purpose

To assess the role of MRI DWI in detection and characterization of ICH.

Patients and methods

61 patients with intracranial hemorrhage who underwent MRI (including DWI, ADC, and GRE) and CT were retrospectively included in this study. MRI DWIs were analyzed for age, type, (primary parenchymal hemorrhage or hemorrhagic lesion) and location of the hemorrhage. The results were compared with conventional MRI sequences, GRE, and CT to assess the diagnostic accuracy of DWI in assessment of patients with intracranial hematoma.

Results

We had 61 patients with intracranial hemorrhage, six cases were missed by DWI. MRI DWI was accurate for the detection of hyperacute, medium, large sized acute, early and late sub acute, subdural, hemorrhagic components of arterial and venous infarction, intraventricular hemorrhage. DWI showed low sensitivity in detection of subarachnoid and small intraparenchymal hemorrhage The ADC measurements in hyperacute, acute, early and late subacute hematoma were statistically equivalent and were significantly less than the late subacute hematoma as well as the contralateral white matter.

Conclusion

MRI DWI was accurate in detection, characterization and staging hyperacute, acute, subacute hemorrhage as well as hemorrhagic components of arterial and venous infarctions and of low diagnostic accuracy in subarachnoid and small parenchymal hemorrhage.     

Role of diffusion MRI and proton magnetic resonance spectroscopy in characterization of ovarian neoplasms

Introduction

Adnexal masses are a common clinical problem and considered as the leading indication for gynecological surgery. The ovary and adnexal structures are relatively difficult to image with any technology. Magnetic resonance spectroscopy (MRS) can detect metabolic changes. As molecular changes often precede morphologic alterations, sensitivity is expected to improve by MRS. Diffusion weighted magnetic resonance imaging (DW-MRI) is sensitive to molecular diffusion which is due to random microscopic translational motion of molecules (known as Brownian motion). In the event of morphologic evaluation of cystic ovarian tumors, whether benign or malignant, DW-MR imaging and calculated apparent diffusion coefficient (ADC) values would be useful for evaluation.

Purpose

The aim of this study is to evaluate the role of diffusion MRI & proton magnetic resonance spectroscopy (H-MRS) in diagnosis of ovarian neoplasms.

Subjects and methods

This study included 20 patients, their ages ranged from 20 to 72 years. In all cases, diagnosis was proven by surgical and pathological examination. Trans-abdominal ultrasound (n = 20) and trans-vaginal ultrasound (n = 11) were included in our routine protocol to obtain baseline information preceding MR examination. The routine MR examination protocol included: T1WI, T2WI, and post contrast fat suppressed T1WI. Diffusion weighted imaging (DWI) was done to all patients at b0, b500, b1000 and ADC values were calculated. MRS was performed in all cases using multi-voxel point resolved surface coil spectroscopy (PRESS sequence) for volume localization.

Results

Fourteen cases (70%) had benign ovarian masses while the remaining six cases (30%) had malignant masses. High lipid peak was detected in all three cases of mature cystic teratoma. All cases of simple serous cysts showed choline and creatine signals that were higher than the average noise level but lower than the two fold higher noise level. Sharp choline peak was detected in all malignant ovarian masses (except a case of metastases under chemotherapy) as well as the case of fibroma. Creatine signal was detected in all benign and malignant masses except two cases of mature cystic teratoma and cases of endometrioma. Lactate signal was detected only in cases of hemorrhagic cysts, mature cyst teratoma and one case of endometrioma and not obtained in any of malignant lesions except dysgerminoma. High NAA signal was detected in dysgerminoma and all three cases of mature cystic teratomas. The mean Cho/Cr ratio was significantly higher in malignant than benign ovarian masses (<0.05), there was no significant difference in mean and lowest ADC values between malignant and benign lesions.

Conclusion

Proton MRS using Cho/Cr ratio added useful information for the diagnosis of different ovarian neoplasms. Direct visual assessment of DWI of ovarian lesions is not useful in differentiating benign from malignant ovarian lesions; determining the threshold of the ADC for diagnosing cystic ovarian tumors is difficult because of their large variance. Further experience with a larger and more biologically variable range of tumors is recommended.     

The relationship between the percentage of lung shunting on Tc-99m macroaggregated albumin (Tc-99m MAA) scan and the grade of hepatocellular carcinoma vascularity

Background

Hepatocellular carcinoma (HCC) stands for the majority of primary liver malignancy. HCC has variable grade of vascularity according to the histological tumor grade and underlying liver damage. Yttrium-90 radioembolization is a promising catheter-based hepatic intra-arterial therapy for HCC that necessitates proper planning. Technetium-99m macroaggregated albumin (Tc-99m MAA), a simulation of the treatment, is used to identify the shunting of microspheres to the lungs or gastrointestinal tract.

Objective

To evaluate the relationship between the percentage of lung shunting on Tc-99m MAA scan performed in treatment planning of Yttrium-90 (Y-90) microsphere selective internal radiation therapy (SIRT) for HCC and the grade of tumor vascularity shown on digital subtraction hepatic angiography.

Materials and methods

This study was conducted on 19 patients diagnosed to have HCC, based on typical computed tomography (CT) criteria and/or elevated alpha-fetoprotein (AFP) ?200 ng/ml, and planned for Y-90 therapy. They were injected by Tc-99m MAA into the hepatic arterial territory with prior digital subtraction angiography. Tc-99m MAA scan was reviewed for extrahepatic shunting within the abdomen. Additionally, the hepatopulmonary shunt (HPS) fraction or the lung shunting (LS) percentage was calculated and further evaluated in relation to the grade of tumor vascularity shown on digital subtraction hepatic angiography.

Results

There was no extrahepatic accumulation of Tc-99m MAA related to umbilical, gastroduodenal or splenic shunting. The LS percentage assorted among patients and ranged between 0.8% and 42.9% with a median of 5.5%. LS more than 20% occurred in only 1 patient. Subsequent therapy plan was changed accordingly in 5% of patients. The more vascular the lesion was, the higher lung shunting percentage was detected.

Conclusion

Tc-99m MAA scan is fundamental prior to Y-90 microsphere SIRT as it minimizes the risk of post-radioembolization complications, hence, enhancing the safety of Y-90 microsphere subsequent administration. Moreover, the percentage of lung shunting varies considerably among patients with HCC relying on the grade of tumor vascularity.     

A two-stage imaging protocol for evaluating women presenting with acute pelvic pain

Purpose

To evaluate a two-stage imaging protocol for diagnosing women presenting with acute pelvic pain.

Materials and methods

Forty-nine female patients aged 20–49 years (mean 29.5 years) who were presenting with acute pelvic pain underwent US examination of the pelvis. MRI of the pelvis was done for seventeen patients with indeterminate ultrasound findings. Data from both MRI and US were obtained, and the definite diagnosis was established with laparoscopic or surgical findings and results of clinical follow-up as the reference standard.

Results

Positive pelvic US and MRI findings for gynecological causes were seen in thirty-six out of forty-nine cases (36/49). Final diagnoses of our positive cases (36) were as follows: hemorrhagic ovarian cyst seven cases (19%), ovarian torsion five cases (14%), endometriosis five cases (14%), teratodermoid four cases (11%), ectopic pregnancy four cases (11%), tubo-ovarian abscess three cases (8%), degenerating fibroid three cases (8%), adenomyosis two cases (6%), pedunculated prolapsed submucosal fibroid one case (3%), uterine AVM one case (3%) and pelvic hematoma one case (3%), Thirteen cases (13/49) were excluded from the study as they had other non gynecological causes of pelvic pain like appendicitis, lower ureteric stones, crohn’s disease and diverticulitis. In 19 cases the diagnosis was established with US alone and so MRI was done for the remaining 17 cases where US was inconclusive.

Conclusion

A two-stage protocol for evaluating women presenting with acute pelvic pain with the use of ultrasonography first, and then MRI for cases with inconclusive ultrasound findings, will optimize diagnostic accuracy.     

Magnetic resonance imaging of the lumbar spine with axial loading: a review of 120 cases

Purpose

To evaluate the imaging findings of patients with clinical symptoms of lower back pain who underwent magnetic resonance imaging (MRI) of the lumbar spine with axial loading.

Materials and methods

We examined 120 patients by MRI, before and after axial loading, using a compression device that applied 50% of their body weight for a load time of 5 min. The dural sac cross area (DSCA) was examined by two experienced radiologists before and after axial load, and their findings were compared. Degenerative abnormalities within and adjacent to the spinal canal were also analyzed.

Results

A reduction in DSCA greater than 15 mm² after axial load was defined as significant, and was found in 81 patients (67.5%) and 138 disc spaces (38.3%). Reduction was most frequent at L4-L5 (n = 55). For other disorders, a 9% increase in cases of bulging disc was seen during axial loading, and seven disc spaces showed protrusion/extrusion only after load. Facet joint synovial cysts, foraminal stenosis, and hypertrophy of the flavum ligaments showed almost no differences, pre- and post-load.

Conclusion

For adequate evaluation of lumbar symptoms, examination should be performed with axial loading, especially in cases of suspected spinal stenosis.     

MR imaging of bladder endometriosis and its relationship with the anterior uterine wall: experience in a tertiary referral centre

Objective

Both the intraperitoneal seeding and the uterine-vesical extension theory have been proposed to explain the pathogenesis of bladder endometriosis. The aim of this study was to describe MR imaging findings of bladder endometriosis and involvement of the anterior uterine wall in a tertiary referral centre for endometriosis in a effort to improve diagnosis and help clarify the pathogenesis.

Methods

In a single-centre, retrospective study (2004–2009), 463 consecutive patients analysed for deep infiltrating endometriosis (DIE) were studied independently by two experienced readers for the presence of bladder endometriosis. MR studies revealing bladder endometriosis were then analysed in consensus for: location, size, signal intensity characteristics, uterine involvement, continuity with adenomyosis and presence of cysts. There was histopathologic correlation in 9 patients who had undergone partial bladder resection.

Results

Bladder endometriosis was diagnosed in 32 patients on MR imaging (k = 0.85). Most lesions showed heterogeneous isointensity compared to that of muscle on T2-weighed imaging, containing foci of high signal intensity, suggesting cystic ectopic endometrial glands. On T1-weighted imaging lesions showed heterogeneous isointensity with foci or small cysts, demonstrating high signal intensity, indicating hemorrhage, was observed. Uterine involvement was found in 94% of the lesions, with either “continuous” or “hourglass” configurations. Presence of contiguous adenomyosis was found in only 4 lesions.

Conclusions

With MR imaging, uterine involvement in bladder endometriosis is frequently found and in most cases located subserosally, suggesting extensive DIE, favouring the intraperitoneal seeding theory.     

The Usefulness of Gadolinium-Enhanced Images on a Follow-up Magnetic Resonance Image in Suspected Multiple Sclerosis

Purpose

Multiple sclerosis diagnostic criteria include the presence of gadolinium-enhancing lesions when determining dissemination in space and time. Gadolinium is expensive, increases scan time and patient discomfort, and can, rarely, cause serious adverse effects. Our objective was to determine the usefulness of including gadolinium-enhanced images as part of a follow-up brain magnetic resonance imaging (MRI) in patients with a clinically isolated syndrome.

Methods

Consecutive patients seen between 2008 and 2010 with a clinically isolated syndrome suggestive of multiple sclerosis were prospectively enrolled, had a non–gadolinium-enhanced brain MRI, and consented to a follow-up gadolinium-enhanced brain MRI. The primary outcome was a comparison of the number of patients diagnosed with multiple sclerosis compared with the number who would have been diagnosed without the gadolinium-enhanced images.

Results

Twenty-one patients enrolled, and 2 withdrew. Follow-up MRIs were performed a median of 241 days after the initial MRI. Eleven patients met the primary outcome and were diagnosed with multiple sclerosis: 6 as a result of a second clinical attack and 5 by using imaging criteria for dissemination in space and time. If the gadolinium-enhanced images had not been obtained, then there would have been no change in the primary outcome.

Conclusions

In Canadian centers with similar MRI waiting times to those in our study, the routine use of gadolinium as part of a follow-up MRI in patients with suspected multiple sclerosis may not be clinically useful. Gadolinium-enhanced images could still be obtained on an as-needed basis for specific clinical indications.     

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.     

Role of novel magnetic resonance imaging sequences in characterization of ovarian masses

Introduction

Differentiating a benign from a malignant adnexal mass would provide a basis for optimal preoperative planning and may also reduce the number of unnecessary laparotomies patients undergoing treatment for benign disease. MRI provides additional information on the composition of soft-tissue masses using differences in MR relaxation properties seen in various types of tissue. More recently developed MRI sequences, like diffusion weighted, susceptibility weighted, and dynamic contrast enhancement sequences provided additional capacities for adnexal lesion tissue characterization.

Aim of the work

The aim of this work was to study the role of MRI including the novel sequences, namely dynamic contrast enhanced MRI (DCE–MRI), diffusion weighted images (DWI) and susceptibility weighted images (SWI) in the characterization of ovarian masses.

Patients and methods

This study included 25 patients having indeterminate adnexal masses at ultrasound. They were subjected to pelvic MRI, including T1, T2, T1 fat sat sequences, as well as the DWI, SWI, and DCE sequences. Final diagnosis was reached through histopathological data, or therapeutic response.

Results

All endometriomas showed blooming on SWI. All malignant lesions showed restricted diffusion and type III DCE curves.

Conclusion

MRI, especially the more recent sequences (DWI, SWI and DCE) allows accurate characterization of ovarian lesions.     

Role of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) in differentiating between benign and malignant breast lesions

Objective

To assess the role of DWI and ADC in differentiating between benign and malignant breast lesions.

Materials and methods

51 patients (age range 24–66 years; mean age 48 years) were included in our study. MRI was done using bilateral fat-suppressed T2- weighted fast spin-echo, STIR, axial T1-weighted fast spin-echo. DWI series were acquired using echo planar imaging pulse sequences incorporated with diffusion gradients and finally dynamic contrast enhancement study was done.

Results

Sixty three lesions were detected in 51 patients included in our study. Twenty one lesions were malignant, three lesions were intermediate and twenty two lesions were fibroadenoma according to the final histopathological study and seventeen lesions were breast cysts. A total of 21 lesions showed lower ADC values than benign lesions and were in the range of 0.76–1.29 × 10⁻³ mm²/s and were diagnosed as malignant breast lesions. The sensitivity and specificity for DWI in the differentiating malignant from benign breast lesions were calculated and showed 95.4% and 97.5%, respectively.

Conclusion

DWI is easy to obtain in short scan time and easy to evaluate, and ADC values can differentiate between benign and malignant breast lesions with high sensitivity and specificity.