Non-hyperfunctioning neuroendocrine tumours of the pancreas: MR imaging appearance and correlation with their biological behaviour

Objective

To describe MR imaging features of non-hyperfunctioning neuroendocrine pancreatic tumours by comparing them to histopathology and to determine the accuracy of MR imaging in predicting biological behaviour.

Materials and Methods

After institutional review board approval, we retrospectively reviewed 45 patients with pathologically proven NF-NET of the pancreas and ≥1 preoperative MR/MRCP examinations. Of the NF-NETS, 29/45 (64.4 %) were G1 and 16/45 (35.5 %) were G2. Image analysis included the lesion maximum diameter, vascular encasement, extrapancreatic spread, signal intensity on T1- and T2-weighted, contrast enhancement features, and presence of metastases. Tumour vessel density was calculated on the histological specimen using a grid.

Results

The median maximum diameter of NF-NETs was 20 mm (range 5–200 mm). Eighty per cent of the NF-NETs were hypointense on T1-weighted images, 82.2 % were hyperintense on T2-weighted images, and 75.6 % were hypervascular. Overall MRI accuracy showed a mean AUC of 0.86 compared to pathology. Lesions with a maximum diameter of 30 mm irregular margins, absence of a cleavage plane with the main pancreatic duct, vascular encasement, extrapancreatic spread and abdominal metastases were significantly associated with malignant NF-NETs. No correlation was found between the tumour vessel density and contrast-enhanced MR imaging pattern.

Conclusions

Hyperintensity on T2-weighted images and iso-/hypervascularity occurred in 27/45 (60.0 %) of NF-NETs. MRI identifies malignant NF-NETs with a sensitivity of 93.3 % and a specificity of 76.9 % (AUC?=?0.85).

Key Points

? Non-hyperfunctioning neuroendocrine pancreatic tumours (NF-NET) pose a difficult diagnostic challenge. ? On T2-weighted MRI, 82.2 % of neuroendocrine tumours appeared hyperintense. ? MR imaging showed 0.94 sensitivity and 0.77 specificity in predicting biological behaviour. ? The hyper-/isointensity during dynamic MRI did not correlate with vessel density at pathology.     

Differentiation between hepatic haemangiomas and cysts with an inversion recovery single-shot turbo spin-echo (SSTSE) sequence using the TI nulling value of hepatic haemangioma with sensitivity encoding

Objective

To evaluate the additional value of inversion recovery (IR) single-shot turbo spin-echo (SSTSE) imaging with sensitivity encoding (SENSE) using the inversion time (TI) value of hepatic haemangioma as a supplement to conventional T2-weighted turbo spin-echo (TSE) imaging for the discrimination of hepatic haemangiomas and cysts.

Methods

A total of 134 lesions (77 hepatic haemangiomas, 57 hepatic cysts) in 59 patients were evaluated. Three readers evaluated these images and used a five-point scale to evaluate the lesion status. A receiver operating characteristic (ROC) analysis and 2?×?2 table analysis were used.

Results

The ROC analysis for all the readers and all the cases revealed a significantly higher area under the curve (AUC) for the combination of moderately and heavily T2-weighted TSE with IR-SSTSE images (0.945) than for moderately and heavily T2-weighted TSE images alone (0.894) (P?<?0.001). For the combination of T2-weighted TSE with IR-SSTSE versus T2-weighted TSE alone, the 2?×?2 table analysis revealed a higher true-positive rate; this difference was statistically significant (P?<?0.0001).

Conclusion

The introduction of IR-SSTSE with SENSE sequences significantly improves the diagnostic accuracy of the differentiation of hepatic haemangioma and cysts while increasing the time required for routine abdominal imaging by only 20 s.     

Myometrial invasion in endometrial cancer: diagnostic performance of diffusion-weighted MR imaging at 1.5-T

Objective

To determine the diagnostic accuracy of diffusion-weighted (DW) magnetic resonance (MR) imaging in the preoperative assessment of myometrial invasion by endometrial cancer.

Materials and methods

In this prospective study, 47 patients with histologically confirmed endometrial cancer underwent preoperative MR imaging and total hysterectomy. The MR protocol included spin-echo multishot T2-weighted, dynamic T1-weighted and DW images acquired with b-values of 0 and 500 s/mm². Myometrial tumour spread was classified as superficial (<50%) or deep (≥50% myometrial thickness). Postoperative histopathological findings served as a reference standard. Indices of diagnostic performance were assessed for each sequence.

Results

At histopathological examination, superficial myometrial invasion was found in 34 patients and deep myometrial invasion in 13. In the assessment of tumour invasion, sensitivity, specificity, positive and negative predictive values of T2-weighted images were 92.3%, 76.5%, 60.0% and 96.3%, respectively. The corresponding values for dynamic images were 69.2%, 61.8%, 40.9% and 84.0%, and for DW images 84.6%, 70.6%, 52.4% and 92.3%. T2-weighted and DW imaging proved to be the most accurate techniques for tumour spread determination.

Conclusion

DW imaging proved to be accurate in assessing myometrial invasion, and it could replace dynamic imaging as an adjunct to routine T2-weighted imaging for preoperative evaluation of endometrial cancer.     

Neoadjuvant chemotherapy for breast cancer: correlation between the baseline MR imaging findings and responses to therapy

Objective:

To retrospectively evaluate the magnetic resonance (MR) imaging findings of breast cancer before neoadjuvant chemotherapy (NAC) and to compare findings of chemosensitive breast cancer with those of chemoresistant breast cancer.

Methods:

The MR imaging findings before NAC in 120 women undergoing NAC were reviewed. The MR imaging findings were compared with the pathological findings and responses.

Results:

A complete response (pCR) and marked response were achieved in 12 and 35% of 120 breast cancers in 120 women respectively. Breast cancers with a pCR or marked response were classified as chemosensitive breast cancer. The remaining 64 breast cancers (53%) were classified as chemoresistant breast cancer. Large tumour size, a lesion without mass effect, and very high intratumoural signal intensity on T2-weighted MR images were significantly associated with chemoresistant breast cancer. Lesions with mass effect and washout enhancement pattern were significantly associated with chemosensitive breast cancer. Areas with very high intratumoural signal intensity on T2-weighted images corresponded pathologically to areas of intratumoural necrosis.

Conclusion:

Several MR imaging features of breast cancer before NAC can help predict the efficacy of NAC.     

Diffusion-weighted and T2-weighted MR imaging for colorectal liver metastases detection in a rat model at 7 T: a comparative study using histological examination as reference

Objectives

To compare diffusion-weighted (DW) and T2-weighted MR imaging in detecting colorectal liver metastases in a rat model, using histological examination as a reference method.

Methods

Eighteen rats had four liver injections of colon cancer cells. MR examinations at 7 T included FSE-T2-weighted imaging and SE-DW MR imaging (b?=?0, 20 and 150 s/mm²) and were analysed by two independent readers. Histological examination was performed on 0.4-mm slices. McNemar’s test was used to compare the sensitivities and the Wilcoxon matched pairs test to compare the average number of false-positives per rat.

Results

One hundred and sixty-six liver metastases were identified on histological examination. The sensitivity in detecting liver metastases was significantly higher on DW MR than on T2-weighted images (99/166 (60 %) (reader 1) and 92/166 (55 %) (reader 2) versus 77/166 (46 %), P?≤?0.001), without an increase in false-positives per rat (P?=?0.773/P?=?0.850). After stratification according to metastasis diameter, DW MR imaging had a significantly higher sensitivity than T2-weighted imaging only for metastases with a diameter (0.6–1.2 mm) similar to that of the spatial resolution of MR imaging in the current study.

Conclusions

This MR study with histological correlations shows the higher sensitivity of DW relative to T2-weighted imaging at 7 T for detecting liver metastases, especially small ones.

Key Points

? Diffusion weighted (DW) sequences are increasingly used in magnetic resonance imaging (MRI). ? DW has higher sensitivity for liver metastases than T2-weighted imaging at 7 T. ? This increase in sensitivity is especially marked for small liver metastasis detection. ? This higher sensitivity is confirmed in an animal model with histological correlation. ? DW imaging has the potential for earlier diagnosis of small liver metastases.     

Hypervascular solid-appearing serous cystic neoplasms of the pancreas: Differential diagnosis with neuroendocrine tumours

Purpose

To describe imaging findings of arterial hypervascular solid-appearing serous cystic neoplasms (SCNs) of the pancreas on CT and MR and determine imaging features differentiating them from neuroendocrine tumours (NETs).

Materials and methods

We retrospectively identified 15 arterial hypervascular solid-appearing SCNs and randomly chose 30 size-matched pancreatic NETs. On CT, two radiologists in consensus assessed the size, morphology, and CT attenuation. On MR, predominant signal intensity and the amount of the cystic component on T2-weighted images and ADC maps were evaluated and compared using Fisher’s exact and Student’s t-test.

Results

The mean SCN size was 2.6 cm (range, 0.8–8.3). The CT findings were similar between the two tumours: location, shape, margin, and enhancement pattern. SCNs were significantly more hypodense on non-enhanced CT images than NETs (P?=?.03). They differed significantly on MR: bright signal intensity (P?=?.01) and more than a 10 % cystic component on T2-weighted images (P?=?.01) were more common in SCNs than in NETs. All SCNs showed a non-restrictive pattern on the ADC map, while NETs showed diffusion restriction (P?<?.01).

Conclusion

Arterial hypervascular solid-appearing SCNs and NETs share similar imaging features. Non-enhanced CT and MR images with T2-weighted images and ADC maps can facilitate the differentiation.

Key points

? Frequency of hypervascular solid-appearing SCNs was 7.3?% among surgically confirmed SCNs.? Hypervascular solid-appearing SCN of the pancreas can mimic pancreatic NETs.? Unenhanced CT and MR features help to differentiate the two tumours.

     

Seven-Tesla MRI of the female pelvis

Objectives

The aim of this study was to investigate the feasibility of 7-T contrast-enhanced MR imaging of the female pelvis.

Methods

Ten healthy female volunteers were examined on a 7-T whole-body MR system utilising a custom-built eight-channel transmit/receive radiofrequency body coil. The examination protocol included (1) T1-weighted fat-saturated 2D spoiled gradient echo (FLASH), (2) dynamic T1-weighted fat-saturated 3D FLASH, and (3) T2-weighted TSE sequences. For qualitative image analysis pelvic anatomy, uterine zonal anatomy and image impairment due to artefacts was assessed using a five-point scale. For quantitative analysis contrast ratios between the junctional zone and myometrium were obtained for T2-weighted MRI.

Results

Two-dimensional FLASH MRI offered the best overall image quality (mean_{contrast-enhanced} 4.9) and highest tissue contrast (mean_{contrast-enhanced} 4.7). T2-weighted TSE imaging provided a moderate to high conspicuity of the uterine zonal anatomy with mean scores ranging from 3.5 for endometrium to 4.65 for myometrium. Overall image impairment was rated strongest for T2-weighted MRI (2.9) and least for 2D FLASH MRI (mean 4.2).

Conclusion

This study demonstrated the feasibility of 7-T T1-weighted MRI of the female pelvis and current constraints associated with T2-weighted MRI.

Key Points

? Dynamic contrast-enhanced female pelvis MR imaging at 7 T is feasible. ? Unenhanced T1-weighted MRI offers inherent hyperintense delineation of pelvic arterial vasculature. ? Two-dimensional FLASH MRI provided best overall image quality and least artefact impairment.     

Head and neck tumours: combined MRI assessment based on IVIM and TIC analyses for the differentiation of tumors of different histological types

Objectives

We evaluated the combined use of intravoxel incoherent motion (IVIM) and time-signal intensity curve (TIC) analyses to diagnose head and neck tumours.

Methods

We compared perfusion-related parameters (PP) and molecular diffusion values (D) determined from IVIM theory and TIC profiles among 92 tumours with different histologies.

Results

IVIM parameters (f and D values) and TIC profiles in combination were distinct among the different types of head and neck tumours, including squamous cell carcinomas (SCCs), lymphomas, malignant salivary gland tumours, Warthin’s tumours, pleomorphic adenomas and schwannomas. A multiparametric approach using both IVIM parameters and TIC profiles differentiated between benign and malignant tumours with 97 % accuracy and diagnosed different tumour types with 89 % accuracy.

Conclusions

Combined use of IVIM parameters and TIC profiles has high efficacy in diagnosing head and neck tumours.

Key points

? Head and neck tumours have wide MR perfusion/diffusion properties. ? Dynamic contrast-enhanced (DCE) MR imaging can characterise tumour perfusion (TIC analysis). ? Intravoxel incoherent motion (IVIM) imaging can provide diffusion and perfusion properties. ? However, IVIM or DCE imaging alone is insufficient for diagnosing head/neck tumours. ? Multiparametric approach using both IVIM and TIC profiles can facilitate the diagnosis.     

MR findings of steatotic focal nodular hyperplasia and comparison with other fatty tumours

Objectives

To correlate MR findings with pathology in steatotic FNHs and to compare the MR findings with those of other fatty tumours developed on noncirrhotic liver in a consecutive series of resected lesions.

Methods

Our population included resected FNH with intralesional steatosis (n?=?25) and other resected fatty tumours selected as controls (hepatocellular adenomas and angiomyolipomas, n?=?34). Lesions were classified into three groups: those with typical FNH without (group 1) or with (group 2) fat on MR and those with atypical lesions (group 3). In group 3, diagnostic criteria for other fatty tumours were applied.

Results

There were 9 lesions in group 1 (15.3 %), 4 in group 2 (16.8 %) and 46 in group 3 (77.9 %). Group 3 contained 12 FNHs (26 %) and all the other fatty tumours. In group 3, the association of lesion homogeneity, signal intensity similar to or slightly different from adjacent liver on in-phase T1- and T2-weighted sequences, and strong arterial enhancement was observed in 7/12 (58 %) of steatotic FNHs and 3/34 (9 %) of other tumours.

Conclusion

On MR, fat within a typical FNH should not reduce the diagnostic confidence. We recommend further investigations including liver biopsy if necessary when fatty tumours exhibit atypical MR findings.

Key Points

? MRI is increasingly used to assess hepatic lesions containing fat. ? Nodules of focal nodular hyperplasia often contain foci of fat. ? However, steatotic FNH does not always demonstrate typical fatty features on MRI. ? The main mimickers of steatotic FNHs are telangiectatic/inflammatory hepatocellular adenomas. ? We recommend liver biopsy when fatty tumours exhibit atypical MR findings.     

Locally advanced rectal cancer: diffusion-weighted MR tumour volumetry and the apparent diffusion coefficient for evaluating complete remission after preoperative chemoradiation therapy

Objective

To evaluate DW MR tumour volumetry and post-CRT ADC in rectal cancer as predicting factors of CR using high b values to eliminate perfusion effects.

Methods

One hundred rectal cancer patients who underwent 1.5-T rectal MR and DW imaging using three b factors (0, 150, and 1,000 s/mm²) were enrolled. The tumour volumes of T2-weighted MR and DW images and pre- and post-CRT ADC_150–1000 were measured. The diagnostic accuracy of post-CRT ADC, T2-weighted MR, and DW tumour volumetry was compared using ROC analysis.

Results

DW MR tumour volumetry was superior to T2-weighted MR volumetry comparing the CR and non-CR groups (P?<?0.001). Post-CRT ADC showed a significant difference between the CR and non-CR groups (P?=?0.001). The accuracy of DW tumour volumetry (A_z?=?0.910) was superior to that of T2-weighed MR tumour volumetry (A_z?=?0.792) and post-CRT ADC (A_z?=?0.705) in determining CR (P?=?0.015). Using a cutoff value for the tumour volume reduction rate of more than 86.8 % on DW MR images, the sensitivity and specificity for predicting CR were 91.4 % and 80 %, respectively.

Conclusion

DW MR tumour volumetry after CRT showed significant superiority in predicting CR compared with T2-weighted MR images and post-CRT ADC.

Key Points

? Diffusion-weighted MR (DWMR) imaging offers new information about rectal cancer. ? DWMR helps to predict complete remission after chemoradiotherapy in patients with advanced rectal cancer. ? DWMR provides more accurate diagnostic information than T2-weighted MRI. ? Apparent diffusion coefficients can predict CR, but they have certain clinical limitations.     

Multimodal imaging utilising integrated MR-PET for human brain tumour assessment

Objectives

The development of integrated magnetic resonance (MR)-positron emission tomography (PET) hybrid imaging opens up new horizons for imaging in neuro-oncology. In cerebral gliomas the definition of tumour extent may be difficult to ascertain using standard MR imaging (MRI) only. The differentiation of post-therapeutic scar tissue, tumour rests and tumour recurrence is challenging. The relationship to structures such as the pyramidal tract to the tumour mass influences the therapeutic neurosurgical approach.

Methods

The diagnostic information may be enriched by sophisticated MR techniques such as diffusion tensor imaging (DTI), multiple-volume proton MR spectroscopic imaging (MRSI) and functional MRI (fMRI). Metabolic imaging with PET, especially using amino acid tracers such as ¹⁸F-fluoroethyl-l-tyrosine (FET) or ¹¹C-l-methionine (MET) will indicate tumour extent and response to treatment.

Results

The new technologies comprising MR-PET hybrid systems have the advantage of providing comprehensive answers by a one-stop-job of 40-50?min. The combined approach provides data of different modalities using the same iso-centre, resulting in optimal spatial and temporal realignment. All images are acquired exactly under the same physiological conditions.

Conclusions

We describe the imaging protocol in detail and provide patient examples for the different imaging modalities such as FET-PET, standard structural imaging (T1-weighted, T2-weighted, T1-weighted contrast agent enhanced), DTI, MRSI and fMRI.

Key Points

? Hybrid MR-PET opens up new horizons in neuroimaging ? Hybrid MR-PET allows brain tumour assessment in one stop ? Hybrid MR-PET allows simultaneous acquisition of structural, functional and molecular images     

Uterine cervical carcinoma: a comparison of two- and three-dimensional T2-weighted turbo spin-echo MR imaging at 3.0 T for image quality and local-regional staging

Objective

To compare three-dimensional (3D) T2-weighted turbo spin-echo (TSE) with multiplanar two-dimensional (2D) T2-weighted TSE for the evaluation of invasive cervical carcinoma.

Methods

Seventy-five patients with cervical carcinoma underwent MRI of the pelvis at 3.0 T, using both 5-mm-thick multiplanar 2D (total acquisition time?=?12 min 25 s) and 1-mm-thick coronal 3D T2-weighted TSE sequences (7 min 20 s). Quantitative analysis of signal-to-noise ratio (SNR) and qualitative analysis of image quality were performed. Local-regional staging was performed in 45 patients who underwent radical hysterectomy.

Results

The estimated SNR of cervical carcinoma and the relative tumour contrast were significantly higher on 3D imaging (P?<?0.0001). Tumour conspicuity was better with the 3D sequence, but the sharpness of tumour margin was better with the 2D sequence. No significant difference in overall image quality was noted between the two sequences (P?=?0.38). There were no significant differences in terms of the diagnostic accuracy, sensitivity, and specificity of parametrial invasion, vaginal invasion, and lymph node metastases.

Conclusion

Multiplanar reconstruction 3D T2-weighted imaging is largely equivalent to 2D T2-weighted imaging for overall image quality and staging accuracy of cervical carcinoma with a shorter MR data acquisition, but has limitations with regard to the sharpness of the tumour margin.

Key Points

? 3D T2-weighted MR sequence is equivalent to 2D for cervical carcinoma staging. ? Coronal 3D acquisitions can reduce the examination time. ? SNR and relative tumour conspicuity were significantly higher on 3D sequences. ? Reformatted 3D T2-weighted imaging had limitations in sharpness of tumour margin.     

Cervicofacial tissue infarction in patients with acute invasive fungal sinusitis: prevalence and characteristic MR imaging findings

Introduction

Tissue infarction is known as one of the characteristic features of invasive fungal sinusitis (IFS). The purpose of this study was to investigate the prevalence and characteristic MR imaging findings of cervicofacial tissue infarction (CFTI) associated with acute IFS.

Methods

We retrospectively reviewed MR images in 23 patients with histologically or microbiologically proven acute IFS. CFTI was defined as an area of lack of enhancement in and around the sinonasal tract on contrast-enhanced T1-weighted images. We divided CFTI into two groups, i.e., intrasinonasal and extrasinonasal. Particular attention was paid to the location of extrasinonasal CFTI and the signal intensity of CFTI on T1- and T2-weighted images. The presence of bone destruction on CT scans was also recorded.

Results

CFTI was found in 17 (74 %) of 23 patients. All of these 17 patients had intrasinonasal CFTI, and 13 patients also had extrasinonasal CFTI. All 13 patients with extrasinonasal CFTI died of disease directly related to IFS. Various locations were involved in the 13 patients with extrasinonasal CFTI, including the orbit (n?=?8), infratemporal fossa (n?=?7), intracranial cavity (n?=?3), and oral cavity and/or facial soft tissue (n?=?4). Various signal intensities were noted at the area of CFTI on T1- and T2-weighted images. Bone destruction was found on CT scans in only 3 of 17 patients with CFTI.

Conclusion

CFTI with preservation of the bony wall of the involved sinonasal tract may be a characteristic MR imaging finding of acute IFS. The mortality is very high once the lesion extends beyond the sinonasal tract.     

Giant cell tumours of the mobile spine: characteristic imaging features and differential diagnosis

Purpose

The aim of this study was to investigate the characteristic imaging features of giant cell tumours (GCTs) of the mobile spine.

Materials and methods

Thirty pathologically proven GCTs of the mobile spine were reviewed. X-ray (n = 18), computed tomography (CT) (n = 24) and magnetic resonance (MR) (n = 21) images were retrospectively evaluated.

Results

Five tumours were located in the cervical spine, 15 tumours were located in the thoracic spine and 10 tumours in the lumbar spine. The characteristic X-ray findings included an osteolytic and expansile lesion with a “soap bubble” or purely lytic appearance. Cortical destruction was commonly seen. Margin sclerosis was seen in two lesions. No mineralised tumour matrix or periosteal reaction appeared. The CT findings were similar but outlined the cortical alterations in a more accurate way. The characteristic MR findings included a well-defined and expansile mass with heterogeneous low-to-iso signal intensity on T2-weighted images. Cystic areas were commonly seen in 17 cases. Five cases presented fluid–fluid levels, suggesting the development of aneurysmal bone cyst. The solid portions of the tumours were enhanced with a very heterogeneous signal pattern reflecting high blood supply after contrast-enhanced scan. Tumour involvement in the epidural space occurred in 12 cases, causing spinal cord and/or nerve root compression. Involvement of intervertebral discs and/or adjacent vertebrae appeared in two cases.

Conclusions

Although rare, GCT can occur in the mobile spine as a kind of benign but locally aggressive tumour. Radiologists should be familiar with its characteristic imaging features in order to make a correct diagnosis and to help preoperative evaluations.     

Diagnostic value of gadolinium-enhanced dynamic MR imaging for parotid gland tumors

Objective

This study aimed to evaluate the value of gadolinium-enhanced dynamic MR imaging for differentiating benign and malignant parotid gland tumors, and for characterizing the various histological types.

Patients and methods

Non-enhanced T1-weighted (T1-W), fat-suppressed T2-weighted (T2-W), and gadolinium-enhanced fat-suppressed dynamic T1-weighted images were obtained preoperatively in 27 patients (28 parotid gland tumors), by using a 1.5 or 3 T MR imaging unit (GE, Signa Exite). The tumor margins and the enhancement curve patterns on dynamic MR imaging were analyzed. All patients underwent a parotidectomy with histopathologic analysis.

Results

Pleomorphic adenomas depict a gradual enhancement pattern. Warthin’s tumors depict an early peak of enhancement and a high washout pattern. Malignant tumors depict an early peak of enhancement and a low washout pattern.

Conclusion

Gadolinium-enhanced dynamic MR imaging improved the performance of MR imaging in differentiating benign from malignant parotid gland tumors and characterizing the different histological types of benign tumors.     

Inflammatory breast carcinoma and locally advanced breast carcinoma: characterisation with MR imaging

Purpose

This study was done to identify the typical magnetic resonance (MR) imaging findings of inflammatory breast carcinoma (IBC) in comparison with noninflammatory locally advanced breast carcinoma (LABC).

Materials and methods

MR images of 30 patients with IBC (T4d) were compared with those of a cohort of 30 patients with LABC (T3/T4a?Cc). The age distribution was approximately equal in the two groups. MR images were assessed for the following features: skin thickening (>4 mm), skin oedema, architectural distortion, enhancement pattern (mass-like/non-mass-like), time-signal intensity curve (continuous-persistent type/wash-out type), skin enhancement. Fisher??s exact text was used to compare MR imaging appearances of IBC and LABC (significant p value <0.05).

Results

Skin involvement and enhancement pattern differed between groups: skin thickening was present in 16/30 IBC (53%) vs 8/30 LABC cases (27%, p=0.06), skin oedema was present in 26/30 IBC (87%) vs 8/30 LABC (27%, p < 0.0001), and skin enhancement in 10/30 IBC (33%) vs 2/30 LABC (7%, p=0.02); non-mass-like enhancement was present in 22/30 IBC (73%) vs 12/30 LABC (40%, p=0.02).

Conclusions

IBC is a distinct clinical and pathological entity resulting in typical MR imaging features. Skin changes (thickening, oedema, enhancement) related to neoplastic involvement of the dermal lymphatics are suggestive of IBC and should prompt a skin biopsy to confirm or rule out the diagnosis.     

Dynamic enhancement features of cavernous sinus cavernous hemangiomas on conventional contrast-enhanced MR imaging

BACKGROUND AND PURPOSE: The reported MR imaging characteristics of cavernous sinus cavernous hemangiomas (CSCHs) in the literature are nonspecific. The purpose of our study was to explore dynamic enhancement features of CSCHs on conventional contrast-enhanced MR imaging and to correlate these features with histopathologic subtypes.MATERIALS AND METHODS: Twenty-one patients (8 male and 13 female; age range, 13–63 years; average age, 42.6 years) with surgically confirmed CSCHs were retrospectively investigated. Preoperative MR study was performed in all cases, consisting of T1-weighted axial imaging, T2-weighted axial imaging, T1-weighted sagittal imaging, and contrast-enhanced T1-weighted axial, sagittal, and coronal images.RESULTS: There were 4.8% (1/21) that showed homogeneous enhancement on all 3 contrast-enhanced sequences, whereas 95.2% (20/21) demonstrated heterogeneous enhancement on the first contrast-enhanced sequence. Among the 20 lesions, on subsequent contrast-enhanced sequences, 55.0% (11/20) showed homogeneous enhancement, whereas 35.0% (7/20) of lesions showed progressive contrast “filling in.” The remaining 10% (2/20) exhibited no apparent enhancement changes. The 95.2% (20/21) of lesions with heterogeneous enhancement on the first contrast-enhanced sequence correlated with type B or type C pathologic findings, whereas 4.8% (1/21) with homogeneous enhancement correlated with type A pathologic findings. Among the 20 type B or type C lesions, 80% (16/20) achieved total or near-total resection.CONCLUSION: Progressive contrast “filling in” in the tumors on conventional contrast-enhanced MR images can aid in differentiating between cavernous sinus lesions and suggest the diagnosis of cavernous hemangiomas.

Cavernous sinus cavernous hemangiomas (CSCHs) are rare vascular malformations, accounting for less than 1% of all parasellar masses.^1,2 Because of their tendency to bleed profusely during surgery, CSCHs require a different surgical approach and technique.^3–5 However, the rate of misdiagnosis is as high as 38.9%.⁶ Although the primary diagnostic tool for CSCHs is MR imaging, there are only scattered reports on their MR characteristics in the literature. The value of these reported MR characteristics is limited in diagnosis and differential diagnosis. However, as a specific characteristic of cavernous hemangiomas in extracranial organs, contrast “filling in” with CSCHs on dynamic MR imaging or CT has not been studied up to now. Our paper is a retrospective review of 21 patients with CSCHs surgically treated at our institution from 2001 through 2007, with particular focus on exploring new MR diagnostic characteristics for this lesion.     

Desmoid-type fibromatosis in the head and neck: CT and MR imaging characteristics

Introduction

In the head and neck region, desmoid-type fibromatosis is an uncommon tumor, and the imaging features have not been well described. The purpose of this study was to describe imaging features with their pathologic correlation of desmoid-type fibromatosis in this region.

Methods

Computed tomographic (CT) and magnetic resonance (MR) images of nine consecutive patients (five women and four men; age range, 2–72 years; mean age, 28 years) with desmoid-type fibromatosis in the head and neck were retrospectively evaluated, focusing on lesion location, size, shape, presence of a rim of surrounding fat, CT attenuation, signal intensity, and enhancement characteristics on MR with pathologic correlation.

Results

Desmoid-type fibromatosis involved perivertebral space (n?=?5) and carotid space (n?=?1) in six adult patients. In three pediatric patients, the fibromatosis primarily involved submandibular space (n?=?2) and masticator space (n?=?1) with frequent invasion to the adjacent spaces (3/3). A mean greatest dimension of 5.8 cm, elongated shape (7/9), and rim of surrounding fat (8/9) were the common features of the desmoid-type fibromatosis. Tumors often showed iso (3/7) or high attenuation (3/7) on postcontrast CT, high signal intensity (6/9) on T2-weighted image, iso signal intensity (8/9) on T1-weighted image, and strong MR enhancement (8/9). Characteristic nonenhancing low signal intensity bands (8/9) on all MR sequences were well correlated with dense collagenous stroma.

Conclusions

Desmoid-type fibromatosis in the head and neck of adults frequently involves perivertebral space. Along with various common imaging features, desmoid-type fibromatosis shows characteristic nonenhancing low signal intensity bands on MR images.     

T2-weighted and delayed enhancement MRI of eosinophilic myocarditis: relationship with clinical phases and global cardiac function

Purpose

To evaluate the usefulness of magnetic resonance imaging (MRI) for detection and quantification of myocardial damage related to clinical phases and cardiac function during eosinophilic myocarditis.

Materials and methods

Four eosinophilic myocarditis patients received seven MRI studies. The left ventricular myocardium was divided into 48 layers, and we quantified the extent of abnormal intensity detected by T2-weighted or delayed enhancement MRI relative to the clinical phase and global cardiac function.

Results

T2-weighted imaging detected extensive myocardial hyperintensity during the acute phase of eosinophilic myocarditis. Diffuse myocardial delayed enhancement was observed in one patient during the acute phase, but not in the other. Little or no hyperintensity was detected by T2-weighted imaging or myocardial delayed enhancement during the convalescent phase. The extent of hyperenhancing myocardial layers was inversely correlated with the ejection fraction (EF) (r = ?0.87).

Conclusion

MRI can evaluate the presence and extent of myocardial damage related to the clinical phases and EF during eosinophilic myocarditis.