Fibrosing inflammatory pseudotumor of the nasopharynx: MR features and histopathologic correlation

Pupose

To describe the magnetic resonance (MR) imaging features of six cases of pathologically proven fibrosing inflammatory pseudotumor involving the nasopharynx, and to compare the MR signal intensities of the lesions with histopathologic findings.

Methods

We reviewed the MR finding of six patients with pathologically proved fibrosing inflammatory pseudotumor at the nasopharyngeal wall with respect to the following points: extent, margins, signal intensity and enhancement degree of the lesion; cervical lymphadenopathy and response to steroid therapy. MR findings were correlated with histopathologic findings.

Results

All lesions showed ill-defined margins and looked less-likely contour bulging features. The signal intensity of the lesions was hypointense or slightly heterogeneous relative to brain cortex on both T1- and T2-weighted images, and enhancement was weakly homogeneous in all cases. There was no demonstrable cervical lymphadenopathy in all cases. After steroid therapy, the lesions showed decreased extent and weaker enhancement in three patients. Histopathologic findings showed high degree of polymorphous inflammatory cellular infiltration with underlying significant reactive fibrosis.

Conclusion

Fibrotic inflammatory pseudotumors involving nasopharynx are very rare, and can mimic malignancy. MR imaging showed ill-defined margins, hypointensity or slightly heterogenous signal intensity on T2-weighted image and weak enhancement. There was no significant cervical lymphadenopathy.     

CT and MR imaging characteristics of infantile hepatic hemangioendothelioma

Aim

This study aims to analyze computed tomography (CT) and magnetic resonance (MR) imaging features of infantile hepatic hemangioendotheliomas before and after treatment.

Materials and methods

CT and MR examinations of seven infants with biopsy proven hepatic hemangioendotheliomas were retrospectively analyzed. The distribution, number, size, imaging appearance, enhancement pattern and post-treatment changes of the tumors were evaluated.

Results

A total of 153 hepatic hemangioendotheliomas were detected on CT (111) and MR (42) imaging. In six infants, 109/111 (98.2%) tumors were hypodense and 2/111 (1.8%) lesions contained calcification on unenhanced CT. On MR imaging, all 42 lesions in one infant were heterogeneously T1-hypointense and T2-hyperintense compared to the normal liver parenchyma. Contrast-enhanced CT and MRI showed peripheral rim (51.6%), uniform (48.4%), fibrillary (33.3%), and nodular (28.8%) contrast enhancement in the hepatic arterial phase. Homogeneous (100%), rim (98.2%) and mixed enhancement patterns were noted in tumors <1.0 cm, >2.0 cm and 1.0-2.0 cm in diameter respectively in the hepatic arterial phase. In three patients who underwent steroid therapy, follow-up CT examination demonstrated tumor size reduction and increased intra-tumoral calcification in two patients.

Conclusion

Infantile hepatic hemangioendotheliomas show some typical imaging features and size-dependent pattern of contrast enhancement on CT and MR imaging, which allow accurate imaging diagnosis and post-treatment evaluation.     

Intraspinal primitive neuroectodermal tumor: Imaging findings in six cases

Purpose

To retrospectively review CT and MRI findings in a series of six intraspinal primitive neuroectoderal tumors and to find out their radiological features.

Methods

CT and MRI of six patients with surgically and pathologically proved intraspinal primitive neuroectoderal tumor were retrospectively reviewed. The tumor location, morphological features, signal intensity, calcification, contrast enhancement characteristics, involvement of paraspinal soft tissues and adjacent bony structures were assessed.

Results

Of six patients, four had extradural lesions and two had intradural, extramedullary lesions. Most lesions were well defined and manifested heterogeneous iso- or hypo-intense signal on T1-weighted imaging and hyper-intense signal on T2-weighted imaging and moderate attenuation on CT, and were heterogeneously enhanced after contrast enhancement. The lesion extending through the intervertebral foramen with a large paraspinal soft tissue mass formed was found in four patients and vertebral bone involvement was seen in four patients.

Conclusions

Although imaging findings are not specific of intraspinal primitive neuroectoderal tumor, this diagnosis could be suggested when MR imaging depicts an intradural, extramedullary or extradural large well-circumscribed mass which extends out from intervertebral foramen and invades paraspinal soft tissues or vertebral bones in a young patient.     

Computed tomography and magnetic resonance imaging findings of peripheral primitive neuroectodermal tumors of the head and neck

Purpose

We aimed to analyze the computed tomography (CT) and magnetic resonance imaging (MRI) findings of peripheral primitive neuroectodermal tumor (pPNET) of the head and neck.

Methods

Eight patients with pPNET of the head and neck confirmed by histopathological examination were analyzed retrospectively.

Results

The average patient age was 8 years. The tumor location in the 8 patients was as follows: maxillofacial region (right, 2; left, 1), left maxillary sinus (1), right masticator space (1), left carotid space (1), right infratemporal fossa (1), and left parotid gland (1). All 5 patients who underwent CT demonstrated ill-defined soft masses and no calcification. Three patients with tumors in the maxillofacial region showed homogeneous small masses and a mild enhancement. The patient with left maxillary sinus tumor showed a heterogeneous mass with patchy, necrotic foci and mild heterogeneous enhancement. The patient with right masticator space tumor showed a heterogeneous mass, and marked heterogeneous enhancement. The T1-weighted images of the patients with right infratemporal fossa, left carotid space, and left parotid gland tumors were isointense. The T2-weighted images were heterogeneous and mildly hyperintense in 2 patients and hyperintense in 1 patient. Heterogeneous intermediate enhancement was demonstrated in 2 patients and mild ring enhancement in 1 patient.

Conclusion

The imaging features of pPNET of the head and neck are non-specific. An ill-defined, aggressive mass and variable enhancement on CT and MR images may suggest the diagnosis of pPNET. Peripheral PNET should be included in the differential diagnosis of children and adolescents’ regional tumors.     

Computed tomography and magnetic resonance imaging findings of solitary fibrous tumors in the pelvis: Correlation with histopathological findings

Objective

We aimed to analyze the computed tomography (CT) and magnetic resonance imaging (MRI) findings of pelvic solitary fibrous tumors (SFTs) and to improve the diagnostic efficacy for such tumors.

Methods

Six cases of pelvic SFTs confirmed by histopathology were analyzed retrospectively. Of the 6 patients, 4 had undergone CT scanning, and 2 had undergone magnetic resonance imaging. All the patients had undergone unenhanced and contrast-enhanced examinations, and 2 had also undergone dynamic CT enhancement examination. Image characteristics such as shape, size, number, edge, attenuation or intensity for each lesion before and after contrast enhancement were analyzed and compared with the pathomorphology of the tumors.

Results

All the 6 cases showed oval or rounded and well-defined masses. Unenhanced CT images showed heterogeneous masses with patchy, necrotic foci in 3 cases and homogeneous mass in 1 case. None of the tumors showed calcification. Contrast-enhanced CT images showed marked, heterogeneous enhancement in the first and second cases. Dynamic enhancement scan demonstrated mild homogeneous enhancement in the third case and mild prolonged, delayed enhancement and washout in the fourth case. T1-weighted MR images showed heterogeneous mild hypointense lesion with linear hyperintensity in 1 case, and homogeneous isointensity in the other. T2-weighted images showed heterogeneous mixed intensity in 1 case and mostly hyperintensive lesion with hypointense foci in another case. A case showed marked heterogeneous enhancement and another showed marked homogeneous enhancement on contrast-enhanced T1-weighted images.

Conclusion

Radiological findings of pelvic SFTs are variable and nonspecific. However, a well-defined, ovoid or rounded mass with hypointense on MR T2-weighted images and variable enhancement on CT and MR images may suggest the diagnosis of SFTs. Pelvic SFTs should be included in the differential diagnosis of regional tumors.     

Imaging of cholangiolocellular carcinoma of the liver

Aim

Cholangiolocellular carcinoma (CoCC) is currently considered to originate from hepatic progenitor cells. The purpose of this study was to evaluate the imaging features of cholangiolocellular carcinoma of the liver.

Materials and methods

Five cases of surgically resected cases of CoCC from 4 institutions were retrospectively evaluated. All of the five patients underwent contrast-enhanced dynamic CT. MRI and angio-CT including CT during arterioportography (CTAP) and CT during hepatic arteriography were performed in 3 and 2 patients, respectively. Histological evaluation was also performed and was correlated with radiographic findings.

Results

On dynamic CT or MRI, the lesions presented hypervascular tumors with delayed washout in 2 cases and in the other 3 cases, the lesions showed peripheral enhancement with concentric delayed filling. On CTAP, the continued existence of portal veins or tiny spots of portal flow was identified in the tumors. Fibrous capsule or tumor necrosis was not observed.

Conclusion

CoCC tumors have the dual imaging characteristics of hepatocellular carcinoma and cholangiocarcinoma. The absence of a fibrous capsule, the absence of tumor necrosis, peripheral location within the liver, and the presence of portal venous penetration within the tumor also appear to be characteristic features.     

Kimura's disease: the CT and MRI characteristics in fifteen cases

Objective

To summarize the CT and MRI features in a series of fifteen cases of Kimura's disease.

Materials and methods

The clinical data, CT and MRI findings of 15 patients with histologically proved Kimura's disease were retrospectively reviewed. All imaging data were consensually evaluated by two radiologists to determine the lesion location, number, morphology, margin, signal intensity or CT density, lesion texture, contrast enhancement pattern and involvement of adjacent structures.

Results

There were 14 male and 1 female, with peripheral blood eosinophilia in all 14 patients. 13 patients were presented with a painless mass. 13 patients had lesions located in the head and neck related to the major salivary glands. 1 patient had lesion in groin. Subcutaneous fat diffuse atrophy around the tumor site was found in 11 patients. 9 patients had solitary mass and 6 patients had multiple masses. Most masses were ill-defined, but no specific density or signal patterns were found. Most patients exhibited enlarged or obviously enhanced abnormal lymph nodes but without necrosis.

Conclusion

The characteristic distribution, morphology with enlarged draining lymphadenopathy, combined with the clinical features and laboratory examination enables a confident preoperative diagnosis of Kimura's disease.     

Small Submucosal Tumors of the Stomach: Differentiation of Gastric Schwannoma from Gastrointestinal Stromal Tumor with CT

Objective

To identify the CT features that help differentiate gastric schwannomas (GS) from small (5 cm or smaller) gastrointestinal stromal tumors (GIST) and to assess the growth rates of both tumors.

Materials and Methods

We included 16 small GSs and 56 GISTs located in the stomach. We evaluated the CT features including size, contour, surface pattern, margins, growth pattern, pattern and degree of contrast enhancement, and the presence of intralesional low attenuation area, hemorrhage, calcification, surface dimpling, fistula, perilesional lymph nodes (LNs), invasion to other organs, metastasis, ascites, and peritoneal seeding. We also estimated the tumor volume doubling time.

Results

Compared with GISTs, GSs more frequently demonstrated a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs (each p < 0.05). The intralesional low attenuation area was more common in GISTs than GSs (p < 0.05). Multivariate analyses indicated that a homogeneous enhancement pattern, exophytic or mixed growth pattern, and the presence of perilesional LNs were statistically significant (p < 0.05). Tumor volume doubling times for GSs (mean, 1685.4 days) were significantly longer than that of GISTs (mean, 377.6 days) (p = 0.004).

Conclusion

Although small GSs and GISTs show similar imaging findings, GSs more frequently show an exophytic or mixed growth pattern, homogeneous enhancement pattern, perilesional LNs and grow slower than GISTs.     

CT features of adenomyosis

Objectives

To determine the computed tomography (CT) features of adenomyosis in patients with known adenomyosis as established with magnetic resonance (MR) imaging.

Methods

A computerized search identified 16 women with pelvic MR diagnosis of adenomyosis who also had enhanced pelvic CT. Original CT reports were reviewed for potential prospective diagnosis of adenomyosis. CT images were reviewed for enhancement phase, inner and outer myometrium attenuation, uterine enlargement (width>6 cm), inner myometrial thickening (≥12 mm), and myometrial cysts.

Results

Adenomyosis was detectable on CT in 8 of 16 patients. For these 8 patients, inner and outer myometrium distinction was excellent in 7 (88%) and limited in 1 (12%), and mean inner myometrial thickness was 25 mm (range 14-47 mm). CT enhancement phase was parenchymal in 7 (88%), uterus was enlarged in 8 (100%), and 7 (88%) had myometrial cysts. Adenomyosis was focal in 5 (63%), diffuse in 2 (25%), and both in 1 (12%). None of the original CT reports included adenomyosis as a diagnosis.

Conclusions

CT can suggest a diagnosis of adenomyosis based on uterine enlargement, thickened inner myometrium, and/or myometrial cysts.     

Evaluation of CT and MRI scanning among cancer patients in Ontario

Background

Computed tomography (CT) and magnetic resonance imaging (MRI) utilization in Ontario increased drastically since the early 1990s. The effect of an increased number of cancer diagnoses, and an increase in indications for scans has not been assessed. This study was conducted to determine trends in utilization of CT and MRI in cancer patients in Ontario over a period of 9 years.

Methods

Using Ontario Health Insurance Plan billing data linked to the Ontario Cancer Registry, rates of CT and MRI were analyzed by region, year, scan type and socioeconomic status.

Results

CT in cancer patients increased 2.3-fold and accounted for approximately 24% of these scans. MRI in cancer patients increased by 4.2-fold and accounted for approximately 10% of these scans. Imaging rates for cancer patients increased more gradually than that of the general population. Substantial variation in the rate of both scans by region of patient residence existed. Even greater variation by the location of the scanner was demonstrated, indicating that many cancer patients traveled outside their region for imaging. There was little evidence of variation in scanning rates by socioeconomic status.

Conclusion

A minority of CT and MRI performed in Ontario are for cancer care. Regional variation in imaging rates suggest that utilization guidelines be developed or knowledge transfer initiatives improve compliance to existing guidelines are needed. A significant number of cancer patients travel outside their region for diagnostic imaging; this should influence decisions about the location of new scanners.     

Metachronous pancreatic metastases from renal cell carcinoma: Role of imaging in a review of 17 cases with surgical correlation

Purpose

To describe the imaging features of pancreatic metastases from renal cell carcinoma.

Patients and methods

Retrospective study of 17 patients with isolated metachronous pancreatic metastases from renal cell carcinoma with surgical and pathological correlation.

Results

The preoperative diagnosis was made on ultrasound in 13 cases. Contrast-enhanced CT showed intense tumor enhancement at the arterial phase, mostly homogeneous but sometimes heterogeneous. There were multiple lesions in six cases. Following complete surgical resection, survival was fairly good.

Conclusion

Long-term follow-up with CT obtained in the arterial and portal venous phases is mandatory. The arterial phase acquisition is essential for the diagnosis of pancreatic metastases from renal cell carcinoma.     

Bone images from dual-energy subtraction chest radiography in the detection of rib fractures

Objective

To assess the sensitivity and image quality of chest radiography (CXR) with or without dual-energy subtracted (ES) bone images in the detection of rib fractures.

Materials and methods

In this retrospective study, 39 patients with 204 rib fractures and 24 subjects with no fractures were examined with a single exposure dual-energy subtraction digital radiography system. Three blinded readers first evaluated the non-subtracted posteroanterior and lateral chest radiographs alone, and 3 months later they evaluated the non-subtracted images together with the subtracted posteroanterior bone images. The locations of rib fractures were registered with confidence levels on a 3-grade scale. Image quality was rated on a 5-point scale. Marks by readers were compared with fracture localizations in CT as a standard of reference.

Results

The sensivity for fracture detection using both methods was very similar (34.3% with standard CXR and 33.5% with ES-CXR, p = 0.92). At the patient level, both sensitivity (71.8%) and specificity (92.9%) with or without ES were identical. Diagnostic confidence was not significantly different (2.61 with CXR and 2.75 with ES-CXR, p = 0.063). Image quality with ES was rated higher than that on standard CXR (4.08 vs. 3.74, p < 0.001).

Conclusions

Despite a better image quality, adding ES bone images to standard radiographs of the chest does not provide better sensitivity or improved diagnostic confidence in the detection of rib fractures.     

Imaging patterns in elastofibroma dorsi

Introduction

Elastofibroma dorsi is a rare pseudotumor of the soft tissues. Its clinico-radiologic characteristics lead to a correct diagnosis.

Material and methods

We followed 43 patients with elastofibroma dorsi with a confirmed histological diagnosis or on the basis of typical imaging pattern (ultrasound, CT, MR) confirmed by evolution.

Results

Elastofibroma is prevalent in females, its onset occurs around 60 years of age and is most frequently localized in the deep subscapular region (93%), bilateral in 54% of cases. In 7% it was found in an atypical isolated suprascapular region, in 7% it was synchronous to that in the subscapular region. Four ultrasound patterns were detected: Type I (54%) inhomogeneous fasciculated, Type II (22%) inhomogeneous aspecific, Type III (15%) hyperechogeneous, Type IV (9%) hypoechogeneous. Three patterns were detected at CT and MR: Type A (84%) inhomogeneous fasciculated corresponding to Types I and III and partially to Type II ultrasound pattern, Type B (8%) inhomogeneous aspecific corresponding to Type II ultrasound pattern; Type C (8%) homogeneous isodense or isointense to the muscle corresponding to Type IV ultrasound pattern.

Conclusion

A solid, slow-growing lesion, in the deep periscapular region in females aged between 50 and 60 years, with a typical fasciculated pattern is pathognomonic of elastofibroma dorsi and bilateral location convalidates diagnosis. Ultrasound is sufficient to orientate diagnosis. CT and/or MR are reserved only for non-fasciculated ultrasound patterns, when site is atypical or in candidates for surgery. Biopsy is reserved only in cases where integrated imaging shows a non-fasciculated pattern to differentiate it from other malignant lesions.     

Potential dependent superiority of gold nanoparticles in comparison to iodinated contrast agents

Purpose

To identify the benefits in image contrast enhancement using gold nanoparticles (AuNPs) compared to conventional iodinated contrast media.

Materials and methods

Gold nanoparticles and iodinated contrast media were evaluated for contrast enhancement at various X-ray tube potentials in an imaging phantom. Iopromide and AuNP suspension were equalized according to molar concentration of radiopaque element (0.5077 Mol/L). Contrast-to-noise ratio is used to quantify contrast enhancement. Both projectional radiographic (40-80 kVp) and computed tomography (CT) (80-140kVp) imaging modalities were examined.

Results and conclusions

Findings indicate 89% improvement in CNR at low energies near the mammographic range (40 kVp). However, as expected no significant difference in enhancement was observed at potentials commonly used for angiography (around 80 kVp) probably due to the k-edge influence for iodine. At the highest energies typically available in computed tomography, significant improvement in contrast enhancement using gold nanoparticles is obtained, 114% greater CNR than that produced by iodine at 140 kVp. Experimental findings for 70-120 kVp spectra correlate well with the theoretical calculations based on linear attenuation coefficients. Superior attenuation of gold nanoparticles at low and high kVp potentials support their further (pre)clinical evaluation.     

Siliconomas mimicking cancer

Introduction

Silicone breast implants are widely used for breast augmentation and breast reconstruction following mastectomy. Implant rupture has specific radiological signs. With the advent use of new imaging technique such as positron emission tomography (PET) computed tomography (CT) and magnetic resonance imaging (MRI) of the breast, these signs may simulate malignancy.

Patients and methods

We retrospectively reviewed four cases of patients with silicon breast implants who arrive to the mammography clinic for further evaluation of a suspected malignant process demonstrated on either PET CT or breast MRI.

Results

Two cases were of PET CT performed for routine oncology follow-up of breast cancer. On both, the PET CT demonstrated multiple-spread benign silicone granulomas manifesting as multiple masses having an increase fluorodeoxyglucose (FDG) uptake. One case of a new mass was demonstrated as a suspicious mass on the dynamic sequences on MRI of the breast. Ultrasound-guided biopsy demonstrated benign tissue response to silicone. One case demonstrated bilateral ruptured breast implants on breast MRI, as well as bilateral axillary and mediastinal lymphadenopathy. Eventually, the patient underwent bronchoscopy for pulmonary workup of dry cough, revealing sarcoidosis.

Conclusion

Silicone granulomas can manifest as masses with suspicious morphology and enhancement dynamics on breast MRI or with increased FDG uptake on PET CT. The presence of silicone implants and awareness of the possibility of a rupture and formation of silicone granulomas may help in facilitating a correct diagnosis.     

What determines the periportal free air, and ligamentum teres and falciform ligament signs on CT: Can these specific air distributions be valuable predictors of gastroduodenal perforation?

Purpose

The purpose of this retrospective study was to determine what gives rise to the periportal free air, and ligamentum teres and falciform ligament signs on CT in patients with gastrointestinal (GI) tract perforation, and whether these specific air distributions can play a clinically meaningful role in the diagnosis of gastroduodenal perforation.

Material and methods

Ninety-three patients who underwent a diagnostic CT scan before laparotomy for a GI tract perforation were included. The readers assessed the presence of specific air distributions on CT (periportal free air, and ligamentum teres and falciform ligament signs). The readers also assessed the presence of strong predictors of gastroduodenal perforation (focal defects in the stomach and duodenal bulb wall, concentrated extraluminal air bubbles in close proximity to the stomach and duodenal bulb, and wall thickening at the stomach and duodenal bulb). The specific air distributions were assessed according to perforation sites, and the elapsed time and amount of free air, and then compared with the strong predictors of gastroduodenal perforation by using statistical analysis.

Results

All specific air distributions were more frequently present in patients with gastroduodenal perforation than lower GI tract perforation, but only the falciform ligament sign was statistically significant (p < 0.05). The presence of all three specific air distributions was demonstrated in only 13 (20.6%) of 63 patients with gastroduodenal perforation. Regardless of the perforation sites, the falciform ligament sign was present significantly more frequently with an increase in the amount of free air on multiple logistic regression analysis (adjusted odds ratio, 1.29; p < 0.001). The sensitivity, specificity, accuracy, and positive predictive and negative predictive values of each strong predictor for the diagnosis of gastroduodenal perforation were higher than those of specific air distributions. The focal wall thickening (accuracy, 95.7%) was the most useful parameter for the diagnosis of gastroduodenal perforation.

Conclusion

The prediction of the perforation site of the GI tract on CT should be based on the presence of strong predictors of the site of bowel perforation, and the specific free air distribution should be regarded as complementary predictors.     

Retroperitoneal ganglioneuroma in children: CT and MRI features with histologic correlation

Objective

To demonstrate the CT and MRI features with histologic correlation of retroperitoneal ganglioneuromas in children.

Methods

The diagnostic images (seventeen CT scans and five MR scans) in 17 children with retroperitoneal ganglioneuroma confirmed by operation and histopathology were retrospectively reviewed, and correlated to the histologic findings.

Results

All tumors presented as an oval-shaped, well-defined mass on both CT and MR images. On unenhanced CT images, calcification was detected in six masses (35.3%), and predominantly low attenuation with the CT value ranged from 22 to 38 HU (mean 29.5 HU) in all the tumors. The tumors with CT value less than 30 HU had a relatively larger amount of myxoid stroma on histopathologic sections than those with CT value more than 30 HU. Tumors showed homogeneous low signal intensity on T1-weighted images and inhomogeneous high signal intensity with interlaced or nodular low signal intensity on T2-weighted images. The post-contrast enhancement on both CT and MR images was lacking or slight in early phase, but moderate or marked in late phase. The inhomogeneous high signal intensity on T2WI, as well as the delayed enhancement corresponded to a large amount of myxoid stroma and a relatively small number of cellular components in tumors.

Conclusion

An oval shape, well-defined margin, low attenuation on CT, inhomogeneous hyperintensity on T2WI, and delayed moderate or marked enhancement are typical features of retroperitoneal ganglioneuroma in children. The imaging features correlated well to the histologic findings.     

胃肠道异位胰腺的CT表现

目的：分析胃肠道异位胰腺（EP）的CT表现,以提高对该病的认识。方法：回顾性分析11例经手术病理或内镜活检证实的胃肠道EP的CT资料,分析总结其特征表现。结果：11例均为单发病灶,位于胃窦小弯侧1例,胃体小弯侧6例,十二指肠3例,空肠1例。EP长径1．6～2．9CITI,短径0．9～1．6cm,长轴均与胃肠道壁平行。7例胃部EP均呈卵圆形;4例肠道EP中,1例呈卵圆形,3例形态不规则。9例边缘模糊,2例边缘清晰。CT平扫示EP密度较均匀,无囊变及坏死。4例显示表面脐凹征,2例中央见导管征。增强示EP均呈明显持续性强化,类似正常胰腺的强化方式。结论：胃肠道EP的长径大小、长轴方向、强化方式、脐凹征及导管征等CT表现具有一定的特征性,联合上述特征可提高该病的诊断水平。     

Comparison of lateral abdominal muscle thickness between weightlifters and matched controls

Objective

To compare lateral abdominal muscle thickness between weightlifters and matched controls.

Design

A case control study design.

Setting

University laboratory.

Subjects

16 female Thai national weightlifters and 16 matched controls participated in this study.

Main outcome measures

Ultrasound imaging with a 12-MHz linear array was used to measure the resting thickness of transversus abdominis (TrA), internal oblique (IO) and total thickness (Total) of lateral abdominal muscle (LAM) on the right side of abdominal wall. The absolute muscle thickness and the relative contribution of each muscle to the total thickness were determined.

Results

Weightlifters had significantly thicker absolute TrA and IO muscles than matched controls (p < 0.01). Further, the relative thickness of the IO was significantly greater in weightlifters than matched controls (p < 0.05).

Conclusions

The findings of this study suggest that routine Olympic style weight training among female weightlifters appears to result in preferential hypertrophy or adaptation of the IO muscle.     

Radiological assessment of mesenteric and retroperitoneal cysts in adults: is there a role for chemical shift MRI?

Objective

The purpose of this study was to assess the potential role for chemical shift magnetic resonance imaging (MRI) in identifying lymphangiomas from other cystic mesenteric and retroperitoneal masses.

Materials and methods

A retrospective search of radiology database identified 24 consecutive patients with mesenteric and retroperitoneal cysts (nine men, 15 women; mean age, 41 years; age range, 19-75 years) who had undergone MR which included in-phase and opposed-phase chemical shift imaging. Signal intensity (SI) decrease between in-phase and opposed-phase MR images of the cyst was evaluated qualitatively by two radiologists. Ultrasound (US), computed tomography (CT), and MRI findings of the morphological appearances of all the cystic lesions that demonstrated significant signal drop on chemical shift MR were also recorded.

Results

Of mesenteric and retroperitoneal cysts, 33% (8/24) revealed qualitative decrease in intensity on opposed-phase MR images relative to that seen on in-phase images. On ultrasound, these cysts demonstrated anechoic simple fluid. Their mean CT attenuation was 13 HU (range: 5-20 HU). Signal loss on fat-suppressed T1-weighted sequences was displayed only by a single cyst. None of the lesions with qualitative SI decrease on opposed-phase MR showed suggestion of lipid on US and CT.

Conclusion

The presence of intra cystic lipid detected by chemical shift MR may not be overt on cross-sectional imaging such as US and CT. Chemical shift MRI provides additional sensitivity and specificity as an imaging test for demonstration of lipid within mesenteric and retroperitoneal cysts enabling a higher diagnostic yield for lymphangioma leading to more appropriate patient management.