Prenatal diagnosis of zellweger syndrome by fetal MRI: a case report

Zellweger Syndrome (ZS) is a rare peroxisomal disorder also referred to as cerebrohepatorenal syndrome. ZS is an autosomal recessive disease often manifesting in the neonatal period with profound dysfunction of the central nervous system, liver and kidneys. Prenatal diagnosis of this syndrome is infrequent with imaging findings on fetal MRI rarely illustrated in the literature. This case highlights the pivotal role fetal MRI can play in identifying subtle features of the disease that are difficult to visualize on prenatal ultrasound. It is important for pediatric radiologists to be familiar with the most common imaging features of ZS on fetal MRI to expedite the diagnosis and help facilitate appropriate prenatal counseling.     

Multiple brain abscesses presented with monoparesis in a patient with lung abscess mimicking lung cancer

Multiple brain abscesses associated with the lung mass require differential diagnosis from cancerous diseases. Here, we report a rare case of multiple brain abscesses originating from a lung abscess. A 65-year-old man presented with a 2-day history of motor weakness during antibiotic treatment for pneumonia. Brain magnetic resonance imaging (MRI) revealed multiple enhanced lesions of various sizes in the whole brain. Diffusion-weighted MRI showed high signal intensity in several lesions, and magnetic resonance (MR) spectroscopy showed reduced N-acetyl-aspartate (NAA) and high lactate-lipid complex levels. Positron emission tomography/computed tomography revealed a hypermetabolic mass-like lesion (size: 5 × 3 cm) in the right lower lobe. The patient was diagnosed with organizing pneumonia by bronchoscopy and was successfully treated with empirical antibiotics for multiple brain abscesses and lung abscesses. If new neurological deficits occur during the treatment of inflammatory diseases such as pneumonia, the possibility of brain abscesses and cancerous conditions should be considered. Appropriate diagnosis and antibiotic treatment should be performed to ensure favorable outcomes.     

Macrocystic lymphatic malformation of the chest wall and axilla: A case report in a 45-year-old man

Lymphatic malformations (LMs) are rare, with more than 90% occurring during childhood. Most LMs are located in the head, neck and axilla. LMs in chest wall are extremely rare, particularly in adults. This report describes a 45-year-old man with a large macrocystic LM in the right anterior chest wall. Computed tomography showed a ∼15 cm sized, well-defined, homogeneous and hypoattenuated mass without enhancement in the right anterior chest wall. On ultrasonography (US), the mass was circumscribed and anechoic, with internal septations and posterior acoustic enhancement. Following surgical excision, the mass was diagnosed as a macrocystic LM.     

Fetal Pericallosal Lipoma: US and MR Findings

We report a case of fetal pericallosal lipoma occurring at the anterior interhemispheric fissure and associated with agenesis of the corpus callosum. During targeted prenatal ultrasonography at 26 weeks'' gestation, the lesion was seen as a highly echogenic mass. MR imaging performed at 35 weeks'' gestation and during the postnatal period revealed a pericallosal fatty mass and agenesis of the corpus callosum.     

Ultrasonographic features of fibrous hamartoma of infancy

Objective

To review imaging features of fibrous hamartoma of infancy (FHI), focusing on ultrasonography (US) findings.

Materials and methods

We retrospectively reviewed pediatric patients who were diagnosed with pathologically confirmed FHI in two children’s hospitals from 2004 to 2013. Imaging features of US, Doppler US, and magnetic resonance imaging (MRI) were evaluated.

Results

Thirteen pediatric patients (M:F?=?7:6; age 5–22 months, mean 11.3 months) were included. Mean lesion size was 3.2 cm (range, 0.7–8.0 cm). The tumors were located in the back (n?=?4), scrotum (n?=?2), scalp, shoulder, axilla, forearm, intergluteal cleft, inguinal area, and thigh. US was performed in 11 patients. With the exception of two scrotal masses, all masses were located in the dermal and subcutaneous layer. All masses demonstrated heterogeneous hyperechogenicity with a “serpentine pattern” of intervening hypoechoic portions in the hyperechoic mass. The margins were ill-defined (n?=?9) or lobulated (n?=?2). Doppler US was performed in nine patients and showed no (n?=?6) or minimal (n?=?3) vascularity. MRI was performed in five patients and the masses showed heterogeneous signal intensity with the presence of fat on T1- and T2-weighted images.

Conclusions

FHI is a tumor that is typically located in the dermal and subcutaneous layer in young children less than 2 years old and presents as a heterogeneously hyperechoic mass with a “serpentine pattern” and ill-defined or lobulated margin on US and no remarkable vascularity on Doppler US.     

髋周骨内脂肪瘤的影像学表现及诊断价值

目的探讨髋周骨内脂肪瘤的影像学表现及其诊断价值。资料与方法结合文献复习,回顾性阅读病理证实的5例髋周骨内脂肪瘤的X线平片和CT片,分析其征象。结果5例均为单发病灶,其中1个病灶位于股骨颈,4个位于髋臼。X线平片表现为边界清或不清的不规则形透光区,可伴硬化缘。CT上病灶为类椭圆形或不规则形的脂肪密度区,CT值为-60～-120HU,最大径为1．0～3．5cm。病灶边缘不规整,伴有厚薄不等的硬化边,其中3个病灶中心和边缘可见小结节状钙化。结论髋周骨内脂肪瘤和其他部位骨内脂肪瘤的影像学表现相似,CT能对其作出正确诊断,可避免不必要的穿刺活检或MRI检查。     

Band-Like Interposing Fat along Large Vessels: Ultrasonographic Pseudolesions of the Breast

Objective

The aim of this study is to evaluate the clinical characteristics and ultrasonographic findings of band-like interposing fat as well as to identify additional approaches for its diagnosis.

Materials and Methods

This study included 26 confirmed cases of band-like interposing fat from June 2008 to June 2010. A retrospective analysis was performed to evaluate the clinical characteristics and ultrasonographic findings in these cases. Five radiologists analyzed the ultrasonographic findings, which correlated with the mammographic and MRI findings when available, according to Breast Imaging Reporting and Data System classification.

Results

None of the 26 patients had any symptoms. In 92.3% of the patients, the lesion was located in the upper outer quadrant of the breast. The mean distance of the lesion from the nipple was 2.4 ± 0.7 cm (1.1-4.5). The mean depth of the lesion from the skin was 1.3 ± 0.3 cm (0.8-2.1). The mean maximal length of the lesion was 0.8 ± 0.4 cm (0.3-1.8). The following were the most frequent ultrasonographic findings of lesions: irregular shape, not parallel orientation, indistinct margins, abrupt interface, hypoechogenicity, no posterior feature, no calcification, and presence of vascularity. The most frequent BI-RADS category was 4a. There were no suspicious findings on the mammography or MRI.

Conclusion

Ultrasonographic findings may lead to misclassification of band-like interposing fat as a malignancy. A better understanding of the clinical and ultrasonographic characteristics of band-like interposing fat would facilitate its differentiation from a true mass.     

Primary neuroendocrine tumor of the liver: A diagnostic dilemma in the management of liver mass in pregnancy

Neuroendocrine tumor (NET) commonly occurs in the gastrointestinal tract, however primary NET of the liver is rare, especially during pregnancy. We present a 34-year-old pregnant woman gravida 3 para 2 at 16 weeks period of gestation with primary liver NET discovered incidentally during the antenatal check-up. She has no risk factors for hepatocellular carcinoma. Her serum alpha-fetoprotein was elevated. A plain magnetic resonance imaging (MRI) of the liver delineating a large well-defined exophytic liver mass at segment V/VI measuring 7.1 × 7.4 × 7.8 cm. Given inconclusive MRI findings coupled with low-risk factors of HCC, we had decided to follow up her liver mass with imaging 6 weekly. She then underwent a right hepatectomy with a caesarean delivery at 32 weeks of gestation in the same setting. The histopathological formal report revealed a neuroendocrine tumor, grade 2 with a Ki-67 index of 3% with negative lymphovascular and perineural invasion, but positive for porta hepatis lymph nodes metastasis. A follow up after 1 year shows both patient and her infant are healthy. Antenatal discovery of liver masses poses a diagnostic and management dilemma to clinicians. A multidisciplinary approach and collective decision making are crucial to determine the best approach tailored to the maternal and fetal benefit. In cases of inconclusive non-contrast MRI in pregnancy with low-risk factors and lack of clinical evidence of HCC, follow-up with imaging modalities aiming to intervene at the third trimester can offer safer, and promising outcomes.     

Clinical study of scrotum scintigraphy in 49 patients with acute scrotal pain: A comparison with ultrasonography

The significance of scrotum scintigraphy in differentiating acute testicular torsion from acute orchiepididymitis was evaluated. In this report, 49 patients with acute scrotal pain were examined with radionuclide scrotum scintigraphy and ultrasonography in parallel for comparison. Of 37 patients with decreased radioactivity in the abnormal side scrotum, 35 were diagnosed with testicular torsion surgically and the other 2 were diagnosed with indirect inguinal hernia. Only 17 among the 35 patients were diagnosed by ultrasonography as having testicular torsion. The remaining 12 patients with increased radioactivity in the abnormal side of the scrotum were all diagnosed with orchiepididymitis through conservative treatment and clinical follow-up, but only 8 of the 12 were correctly and exactly diagnosed by ultrasonography. In the process of diagnosing acute scrotal pain, radionuclide scrotum scintigraphy has obvious advantage over ultrasonography. It also has the advantage of being simple, fast and accurate but without any detrimental effect on the human body.     

椎管闭合不全的MRI诊断(附27例分析)

目的:分析椎管闭合不全的MRI表现特点,评价MRI诊断和鉴别诊断的价值。方法:回顾性分析27例椎管闭合不全的MRI资料,经手术证实9例,MR表现典型18例。结果:MRI显示偏侧脊髓脊膜膨出1例,腰段椎管后裂开,脊髓裂开,左侧脊髓脊膜向后膨出。脊髓纵裂2例,脊髓硬膜囊被骨性或纤维间隔分开。脂肪脊髓裂5例,骶管裂开且皮下脂肪突入椎管内,脂肪瘤—基板界面位于骶管内。脂肪脊髓脊膜膨出2例,腰骶管后裂开且腰骶皮下脂肪瘤通过裂口疝入硬膜下,横断位见脂肪瘤—基板界面位于骶管外。脊膜膨出6例,腰骶背部皮下囊状突出物与蛛网膜下腔脑脊液相通。硬膜下脂肪瘤4例,硬膜下病变在T1WI及T2WI上呈高信号。终丝脂肪瘤4例,T1加权像上见终丝结节状、线条状脂肪信号。椎管内畸胎瘤2例,硬膜囊内不均匀信号团块状占位。骶管内脊膜囊肿1例,骶管内椭圆形在T1WI呈低信号,T2WI呈高信号影。结论:每型椎管闭合不全有相应的MRI表现特点,大多数MRI可准确诊断。     

Use of Quantitative Vertebral Bone Marrow Fat Fraction to Assess Disease Activity and Chronicity in Patients with Ankylosing Spondylitis

ObjectiveWe quantitatively measured the fat fraction (FF) in the vertebrae of patients with ankylosing spondylitis (AS) using magnetic resonance imaging (MRI) and investigated the role of FF as an indicator of both active inflammation and chronicity.Materials and MethodsA total of 52 patients with AS who underwent spinal MRI were retrospectively evaluated. The FF values of the anterosuperior and anteroinferior corners of the bone marrow in the L1-S1 spine were assessed using the modified Dixon technique. AS activity was measured using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), AS Disease Activity Score (ASDAS), and serum inflammatory marker levels. AS disease chronicity was assessed by AS disease duration and the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). Univariable and multivariable regression analyses were conducted to investigate the correlation between FF and other clinical characteristics.ResultsThe mean FF ± standard deviation of the total lumbar spine was 43.0% ± 11.3%. At univariable analysis, spinal FF showed significant negative correlation with BASDAI (β = −0.474, p = 0.002) and ASDAS with C-reactive protein (ASDAS-CRP; β = −0.478, p = 0.002) and a significant positive correlation with AS disease duration (β = 0.440, p = 0.001). After adjusting for patient age, sex, and total mSASSS score, spinal FF remained significantly negatively correlated with BASDAI (β = −0.543, p < 0.001), ASDAS-CRP (β = −0.568, p < 0.001), and ASDAS with erythrocyte sedimentation rate (β = −0.533, p = 0.001). Spinal FF was significantly lower in patients with very high disease activity (ASDAS-CRP > 3.5) than in those with only high disease activity (2.1 ≤ ASDAS-CRP ≤ 3.5) (p = 0.010).ConclusionSpinal FF may help assess both AS disease activity and chronicity.     

FDG-PET/CT Is Superior to Enhanced CT in Detecting Recurrent Subcentimeter Lesions in the Abdominopelvic Cavity in Colorectal Cancer

Purpose

This study aims to compare the performance of contrast-enhanced computed tomography (CeCT) and 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in detecting small tumor implants and metastatic lymph nodes (LNs) in the abdominopelvic cavity in patients with colorectal cancer.

Methods

We enrolled 16 patients who were clinically suspected of experiencing a recurrence (6 male, 10 female; mean age 61 ± 14 years). All subjects underwent CeCT and PET/CT, and the performance of these methods was compared with regard to detecting recurrences. The final diagnosis of a recurrence was made clinically.

Results

CeCT identified 38 lesions in 12 patients, all of which were detected by PET/CT. PET/CT found 27 additional lesions in 8 patients, comprising 9 seeding nodules (2 in the right upper quadrant of the abdomen and 7 in the pelvic cavity) and 18 LNs (2 celiac, 2 paraaortic, 2 hepatic hilar, 11 common iliac, 1 external iliac). Most additional lesions were located in the pelvic cavity (approximately 78% of seeding nodules and 67% of lymph nodes). The maximum standardized uptake value (SUVmax) of the additional seeding nodules that were detected solely by PET/CT was significantly higher compared with the CeCT- and PET/CT-confirmed nodules (5.5 ± 4.2 vs. 2.9 ± 2.5, p = 0.03). The seeding nodules that were detected only by PET/CT were significantly smaller than the CeCT- and PET/CT-confirmed nodules (long axis: 1.0 ± 0.3 cm vs. 2.0 ± 1.1 cm, p = 0.001; short axis: 0.8 ± 0.3 cm vs. 1.4 ± 0.8 cm, p = 0.004; mean of both axes: 0.9 ± 0.3 cm vs. 1.7 ± 0.9 cm, p = 0.001). Similarly, PET/CT-only-detected LNs were significantly smaller than CeCT- and PET/CT-identified LNs (0.7 ± 0.1 cm vs. 2.3 ± 1.2 cm, p < 0.0001).

Conclusion

PET/CT is superior to CeCT in detecting seeding nodules and metastatic LNs in patients with recurrent colorectal cancer. Specifically, PET/CT detects subcentimeter lesions in anatomically deformed pelvic cavities.     

Ultrasound of Lipomatosis of Nerve Associated with Macrodactyly: ‘Spaghetti and Chocolate Cookie’ Appearance

We studied the US imaging findings of lipomatosis of nerve and macrodystrophia lipoma in three patients.Three patients were seen at three affiliated institutions with an enlarged digit. They all underwent US, subsequently followed by an MRI study.The nerves showed marked enlargement and extension over a length of 9–16 cm. Digital branches were always involved. The appearance on cross section was an enlarged hyperechoic endoneurium with inlying thickened and hypoechoic fascicles. On transverse images this resulted in a ‘chocolate cookie’ aspect and in the long axis a ‘spaghetti-like’ image.The US appearance of lipomatosis of nerve, not unlike MRI, is rather typical. With US, care should be taken in areas that are more difficult to assess as the sole of the foot, or where the ‘chocolate cookie’ appearance is not so obvious, such as the digits.     

Antenatal diagnosis of vein of Galen aneurysmal malformation: MR study of fetal brain and postnatal follow-up

About 20 cases of prenatal diagnosis of vein of Galen aneurysmal Malformation (VGAM) have been described. We present a case diagnosed prenatally by Doppler ultrasonography. Prenatal MRI and postnatal radiological studies including post-treatment MRI and MRA, were carried out.     

Evaluation of current clinical target volume definitions for glioblastoma using cell-based dosimetry stochastic methods

Objective:

Determination of an optimal clinical target volume (CTV) is complex and remains uncertain. The aim of this study was to develop a glioblastoma multiforme (GBM) model to be used for evaluation of current CTV practices for external radiotherapy.

Methods:

The GBM model was structured as follows: (1) a Geant4 cellular model was developed to calculate the absorbed dose in individual cells represented by cubic voxels of 20 μm sides. The system was irradiated with opposing 6 MV X-ray beams. The beams encompassed planning target volumes corresponding to 2.0- and 2.5-cm CTV margins; (2) microscopic extension probability (MEP) models were developed using MATLAB^® 2012a (MathWorks^®, Natick, MA), based on clinical studies reporting on GBM clonogenic spread; (3) the cellular dose distribution was convolved with the MEP models to evaluate cellular survival fractions (SFs) for both CTV margins.

Results:

A CTV margin of 2.5 cm, compared to a 2.0-cm CTV margin, resulted in a reduced total SF from 12.9% ± 0.9% to 3.6% ± 0.2%, 5.5% ± 0.4% to 1.2% ± 0.1% and 11.1% ± 0.7% to 3.0% ± 0.2% for circular, elliptical and irregular MEP distributions, respectively.

Conclusion:

A Monte Carlo model was developed to quantitatively evaluate the impact of GBM CTV margins on total and penumbral SF. The results suggest that the reduction in total SF ranges from 3.5 to 5, when the CTV is extended by 0.5 cm.

Advances in knowledge:

The model provides a quantitative tool for evaluation of different CTV margins in terms of cell kill efficacy. Cellular platform of the tool allows future incorporation of cellular properties of GBM.     

A case of thrombosis mimicking a buccal tumour: usefulness of MRI

A rare case of thrombosis mimicking a tumour in the buccal region is reported. Since the entire round mass was located deeply, it was difficult to diagnose. Contrast computed tomography, magnetic resonance imaging (MRI) and ultrasound examinations may be useful, but MRI was most useful in this case because it allowed prediction of different kinds of histological structures in the soft tissue. The findings of T1 weighted imaging, T2 weighted imaging and examination with Gd-DTPA on T1 weighted imaging are useful for predicting the character of deeper soft tissue masses, and can differentiate thrombosis from lymphadenopathy, lipoma and other lesions.     

MRI features of cellular angiomyofibroma with pathologic correlation

Within the spectrum of extratesticular mesenchymal tumors in the scrotum and perineum lies cellular angiofibroma, also known as angiomyofibroblastoma‐like tumor, a rare lesion originally described to almost exclusively occur in the vulva, perineum, and pelvis of women. We report a case of this tumor, with an adjacent scrotal lipoma, occurring in a 60‐year‐old male who presented to our department with a firm palpable scrotal mass. To our knowledge, the MRI findings of this entity have yet to be described in the radiological literature. We present the MRI features of cellular angiofibroma that are consistent with the pathological characteristics of this entity—a benign cellular and fibrous tumor with prominent vascularity. J. Magn. Reson. Imaging 2009;29:1195–1198. © 2009 Wiley‐Liss, Inc.     

Three Dimensional Ultra-short Echo Time MRI Can Depict Cholesterol Components of Gallstones Bright

PurposeNon-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective in vitro study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO₃ (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline.MethodsFourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared.ResultsBC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, −10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, −11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = −0.885, (P < 0.0001), UTE MRI first echo r = −0.524 (P = 0.0072) and UTE subtraction with r = 0.598 (P = 0.0016).ConclusionUTE MRI and UTE subtraction can depict CC bright.     

MRI findings of solitary fibrous tumours in the head and neck region

Objectives:

To analyse the MRI findings of solitary fibrous tumours in the head and neck region.

Methods:

We retrospectively reviewed MR images in eight patients with solitary fibrous tumours proven on histological examination. All the patients underwent conventional MRI, and four patients also underwent dynamic contrast-enhanced MRI and diffusion-weighted imaging in five cases. Image characteristics were analysed.

Results:

All lesions were found as solitary well-defined masses ranging in size from 1.9 to 6.8 cm (mean, 4.1 cm). They were mostly homogeneous and isointense to the muscle on T₁ weighted images and heterogeneous and mildly hyperintense on T₂ weighted images. After gadolinium administration, areas that were mildly hyperintense on T₂ weighted images were strongly enhanced. They were mildly hyperintense on diffusion-weighted imaging. The average tumour-apparent diffusion coefficient values were 0.001 157 ± 0.000 304 9 mm s⁻² compared with the muscle 0.000 760 ± 0.000 265 0 mm s⁻², and there was a statistical difference of p = 0.002. The time–intensity curves exhibited a rapidly enhancing and a slow washout pattern on dynamic contrast-enhanced MRI.

Conclusions:

Solitary fibrous tumours should be considered in cases of heterogeneous hypervascular tumours in the head and neck region. Areas of mild hyperintense intensity on T₂ weighted images that are strongly enhanced after gadolinium injection are suggestive of this diagnosis. Non-restricted diffusion and rapidly enhancing and slow washout pattern time–intensity curves may be additional valuable features.     

Serial fetal magnetic resonance imaging of cloacal exstrophy

Cloacal exstrophy (CE) is a rare congenital malformation involving the urinary, intestinal, and genital systems. We present a case of CE in which characteristic findings were detected at two serial fetal magnetic resonance imaging (MRI) sessions. At 18 weeks’ gestation, the initial fetal MRI revealed a cystic mass protruding from the infra-umbilical abdominal wall. During fetal development, the cystic mass disappeared, and an omphalocele and heterogeneous soft tissue mass were recognized at 28 weeks’ gestation. The bladder was not visualized on either examination. CE can be diagnosed by prenatal MRI, thereby permitting prenatal counseling and appropriate postnatal management.