The iliac wing sign: an indicator of the presence of bone and/or soft-tissue injury of the pelvis and hips

Purpose

To prospectively evaluate the feasibility of using the “iliac wing sign (IWS)” as an indicator of bone and/or soft-tissue injury of the pelvis and hips on magnetic resonance (MR) imaging. IWS means edema of the iliacus muscle attachment entering the iliac wing that is visualized as a linear high signal intensity on fat-suppressed T2-weighted MR images.

Methods

Consecutive 106 patients who complained of hip pain were enrolled in this study. We evaluated the correlation between IWS and bone and/or soft-tissue injury of the pelvis and hips using Fisher's exact test. Further, performance parameters of sensitivity, specificity, accuracy, the positive predictive value (PPV), and negative predictive value (NPV) of IWS were calculated.

Results

Thirty-eight of the 106 (36%) patients had bone and/or soft-tissue injury. Twenty-seven of these 38 (71%) patients with injury showed a positive IWS, while only 11 of 68 (16%) patients without injury showed a positive IWS (p < .0001). IWS, thus, yielded a sensitivity of 71%, specificity of 84%, accuracy of 79%, positive predictive value (PPV) of 71%, and negative predictive value (NPV) of 84%.

Conclusion

In cases with a positive IWS, the careful interpretation of MR images is needed because injury presence is highly likely, as suggested by the relatively high sensitivity and PPV. IWS absence may mean a low probability of injury because of the high specificity and NPV.     

A vast increase in the use of CT scans for investigating occult hip fractures

Background

Early diagnosis in neck of femur fractures has been shown to improve outcome. The National Institute for Clinical Excellence recommends if an occult hip fracture is suspected then an MRI should be performed and if not available within 24 h a CT should be considered. At our centre, emergency MRI is rarely available and so CT is commonly used.

Objectives

Our study aims to analyse the trends in CT use over a five year period for the diagnosis of neck of femur fractures.

Methods

Both the number of patients with a hip fracture and those undergoing a CT hip to diagnose an occult injury were identified across two district general hospitals between 2006–2007 and 2010–2011. The time from initial radiograph to CT and initial radiograph to operation were calculated.

Results

In 2006–2007, of 547 hip fractures, 20 CT hips were performed and 6 reported as a fractured neck of femur (30%). In 2010–2011, of 499 hip fractures, 239 CT hips were performed and 65 fractures were recognised (27%). The mean time from radiograph until CT scan was 2.0 days in 2007 and 3.2 days in 2011, which was a statistically significant difference (p < 0.001). For those diagnosed using a CT scan the mean time from admission X-ray to surgery was 1.2 days in 2007 and 3.6 days in 2011.

Conclusion

Clinicians are becoming increasingly reliant on CT for the diagnosis of hip fractures with our data suggesting further imaging is one factor that can delay time to diagnosis and theatre.     

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.     

Apparent avascular necrosis of the hip: appearance and spontaneous resolution of MR findings in renal allograft recipients

The sensitivity of magnetic resonance (MR) imaging in the detection of avascular necrosis (AVN) of the hip and natural history of the MR findings were determined prospectively in renal allograft recipients, a group at risk for development of the disease. One hundred four patients were studied up to 24 months after transplantation. In 25 hips in 14 patients, MR findings were consistent with AVN. Pain developed in seven hips in four patients; in each hip, the MR images showed abnormality before the onset of symptoms. Plain radiographs showed abnormality in all hips that became painful; however, the plain radiographs of 17 of 18 asymptomatic hips in which MR imaging showed evidence of AVN showed no abnormality over a mean follow-up period of 16 months. All MR lesions in the symptomatic hips were larger than those in the asymptomatic cohort. MR lesions in seven hips (in five asymptomatic patients) regressed in size; in six hips, the MR images returned to normal. The findings suggest that some patients with MR evidence of AVN of the hip have spontaneous improvement.     

Colour Doppler Ultrasound Assessment of the Normal Neonatal Hip

Objective

To determine the morphology and hemodynamic characteristics of the arterial vessels of the proximal femur according to specific anatomic regions in asymptomatic neonates in 2 pediatric-based health care institutions.

Methods

Forty-three neonates (29 female, 14 male; age range, 2 d–3 mo; median age, 3 d) were enrolled in the study. Thirty-two (37%) of 86 hips were classified as Graf type IIA joints (mean alpha angle, 56.0° ± 2.7°), and 54 (63%) were classified as type I joints (mean alpha angle, 65.0° ± 4.6°).

Results

Colour and spectral Doppler imaging identified vessels running along the acetabular labrum, epiphyseal vessels, and femoral neck. We showed 4 different patterns of vascularity of the hips: radial, parallel, mixed radial–parallel, and indeterminate, however, they were not related to the hip maturity (P = .3, coronal plane; P = .62, transverse plane) or to the amount of colour pixels identified in each region (P = .35). The mean number of pixels in the ligamentum teres region was significantly higher than that in other regions of interest (P = .03). Except for the acetabular labrum arteries, Doppler spectrum waveforms of proximal femur arteries presented with low resistivity. There was a tendency towards females' acetabular arteries presenting with lower peak systolic velocities than males' acetabular arteries (P = .06).

Conclusions

Colour Doppler spectrum waveforms and intensity of vascularity in normal neonatal hips differ according to the anatomic region under evaluation. This observation deserves further investigation on its role on the physiopathogenesis of neonatal hip disorders.     

FDG PET/MR for lymph node staging in head and neck cancer

Objective

To assess the diagnostic value of PET/MR (positron emission tomography/magnetic resonance imaging) with FDG (18F-fluorodeoxyglucose) for lymph node staging in head and neck cancer.

Materials and methods

This prospective study was approved by the local ethics committee; all patients signed informed consent. Thirty-eight patients with squamous cell carcinoma of the head and neck region underwent a PET scan on a conventional scanner and a subsequent PET/MR on a whole-body hybrid system after a single intravenous injection of FDG. The accuracy of PET, MR and PET/MR for lymph node metastases were compared using receiver operating characteristic (ROC) analysis. Histology served as the reference standard.

Results

Metastatic disease was confirmed in 16 (42.1%) of 38 patients and 38 (9.7%) of 391 dissected lymph node levels. There were no significant differences between PET/MR, MR and PET and MR (p > 0.05) regarding accuracy for cervical metastatic disease. Based on lymph node levels, sensitivity and specificity for metastatic involvement were 65.8% and 97.2% for MR, 86.8% and 97.0% for PET and 89.5% and 95.2% for PET/MR.

Conclusions

In head and neck cancer, FDG PET/MR does not significantly improve accuracy for cervical lymph node metastases in comparison to MR or PET.     

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

Purpose

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

Materials and methods

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

Results

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

Conclusion

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

Posterior reversible encephalopathy syndrome with atypical regions in eclamptic patients: A challenge for radiologists

Purposes

To determine the distribution and incidence of atypical regions of involvement of PRES in eclapmtic patients by using MR imaging.

Material and methods

A prospective study was approved by the ethical committee of our institution during the period between October 2011 and March 2012. Twenty two registered eclamptic patients (age ranged from 20–38 years; average 29 years) who had clinical signs and symptoms of PRES were recruited in the study, all patients were referred from Gynecology and Obstetric department, for brain MRI to evaluate PRES after clinical suspicion. All images were reviewed for the presence of high signal intensity on FLAIR and T2WI, for the severity of the vasogenic brain edema, on the basis of the extent of hyperintensity on FLAIR imaging. DWI was also interpreted for the presence or absence of areas of restricted diffusion corresponding to the hyperintensity areas on T2WI and FLAIR images.

Results

The most common clinical presentations were seizures, and altered mental status seen in 11 patients (50%). Other clinical presentations included headache (4 [18.1%]), visual disturbance in one patient and loss of consciousness in one patient. Most commonly involved location was the parieto-occipital brain region, which was seen in 19 (86.3%) of the (22) patients. This was followed by the frontal lobe in 13 patients (59%), the temporal lobe in 3 (13.6%), Basal Ganglia in 3 patients and cerebellum in 3 patients, 11 (50%) had subcortical involvement of white matter edema and 9 (40.9%) had cortical involvement. Lesions were asymmetric in nearly half of the cases (n = 10[45.5%]), unilateral in 3 patients. Restricted diffusion was present in 9 patients (40.9%), and no hemorrhage was present in all patients. As regarding severity of edema in FLAIR, half of patients had moderate edema (n = 11) while only 2 patients had severe edema and 9 had mild edema.

Conclusion

PRES can affect anterior circulation structures and atypical regions fairly frequent than commonly known. However, a posterior predominance is certainly seen in each lobe. Atypical regions of involvement represents a challenge for radiologist and necessitate strict clinical correlation and follow up.     

Magnetic resonance perfusion and diffusion imaging characteristics of transient bone marrow edema,avascular necrosis and subchondral insufficiency fractures of the proximal femur

Purpose

To evaluate magnetic resonance (MR) perfusion and diffusion imaging characteristics in patients with transient bone marrow edema (TBME), avascular necrosis (AVN), or subchondral insufficiency fractures (SIF) of the proximal femur.

Materials and methods

29 patients with painful hip and bone marrow edema pattern of the proximal femur on non-contrast MR imaging were examined using diffusion-weighted and dynamic gadolinium-enhanced sequences. Apparent diffusion coefficients (ADCs) and perfusion parameters were calculated for different regions of the proximal femur. Regional distribution and differences in ADC values and perfusion parameters were evaluated.

Results

Seven patients presented with TBME, 15 with AVN and seven with SIF of the proximal femur. Perfusion imaging showed significant differences for maximum enhancement values (E_max), slope (E_slope) and time to peak (TTP) between the three patient groups (p < 0.05). In contrast, no significant differences for ADC values were calculated when comparing TBME, AVN, and SIF patients.

Conclusion

Diffusion weighted imaging of bone marrow of the proximal femur did not show significant differences between patients with TBME, AVN or SIF. In contrast, MR perfusion imaging demonstrated significant differences for the different patient groups and may as a complementary imaging technique add information to the understanding of the pathophysiology of diseases associated with bone marrow edema.     

Prediction of three-dimensional femoral offset from AP pelvis radiographs in primary hip osteoarthritis

Background

In pre-operative planning for total hip arthroplasty (THA), femoral offset (FO) is frequently underestimated on AP pelvis radiographs as a result of inaccurate patient positioning, imprecise magnification, and radiographic beam divergence. The aim of the present study was to evaluate the accuracy and reliability of predicting three-dimensional (3-D) FO from standardised AP pelvis radiographs.

Methods

In a retrospective cohort study, pre-operative AP pelvis radiographs, AP hip radiographs and CT scans of a consecutive series of 345 patients (345 hips, 146 males, 199 females, mean age 60 (range: 40–79) years, mean body-mass-index 27 (range: 19–57) kg/m²) with primary end-stage hip OA were reviewed. Patients were positioned according to a standardised protocol and all images were calibrated. Using validated custom programmes, FO was measured on corresponding radiographs and CT scans. Measurement reliability was evaluated using intra-class-correlation-coefficients. To predict 3-D FO from AP pelvis measurements and to assess the accuracy compared to CT, the entire cohort was randomly split into subgroups A and B. Gender specific regression equations were derived from group A (245 patients) and the accuracy of prediction was evaluated in group B (100 patients) using Bland–Altman plots.

Results

In the entire cohort, mean FO was 39.2 mm (95%CI: 38.5–40.0 mm) on AP pelvis radiographs, 44.1 mm (95%CI: 43.4–44.9 mm) on AP hip radiographs and 44.6 mm (95%CI: 44.0–45.2 mm) on CT scans. In group B, we observed no significant difference between gender specific predicted FO (males: 48.0 mm, 95%CI: 47.1–48.8 mm; females: 42.0 mm, 95%CI: 41.1–42.8 mm) and FO as measured on CT (males: 47.7 mm, 95%CI: 46.1–49.4 mm, p = 0.689; females: 41.6 mm, 95%CI: 40.3–43.0 mm, p = 0.607).

Conclusions

The present study suggests that FO can be accurately and reliably predicted from AP pelvis radiographs in patients with primary end-stage hip osteoarthritis. Our findings support the surgeon in pre-operative templating on AP-pelvis radiographs and may improve offset and limb length restoration in THA without the routine performance of additional radiographs or CT.     

Greater trochanter pain syndrome: A descriptive MR imaging study

Objective

Greater trochanter pain syndrome (GTPS) is a diverse clinical entity caused by a variety of underlying conditions. We sought to explore the impact of (1) hip morphology, namely the center-edge angle (CEa) and femoral neck-shaft (NSa) angle, (2) hip abductor tendon degeneration, (3) the dimensions of peritrochanteric edema and (4) bursitis, on the presence of GTPS, using MR imaging.

Materials and methods

The presence of pain was prospectively assessed blindly by the senior author. CEa and NSa were blindly measured in 174 hip MR examinations, after completion of the clinical evaluation by another evaluator. The existence and dimensions of T2 hyperintensity of the peritrochanteric soft tissues, the existence and dimensions of bursae, as well as degeneration and tearing of gluteus tendons were also recorded.

Results

Out of 174 examinations, 91 displayed peritrochanteric edema (group A) and 34 bursitis, all with peritrochanteric edema (group B). A number of 78 patients from both A and B groups, showed gluteus medius tendon degeneration and one tendon tear. CEa of groups A and B were 6° higher than those of normals (group C, P = 0.0038). The mean age of normals was 16.6 years less than in group A and 19.8 years less than in group B (P < 0.0001). Bursitis was associated with pain with a negative predictive value of 97% (P = 0.0003).

Conclusion

Acetabular morphology is associated with GTPS and the absence of bursitis was proved to be clinically relevant. Peritrochanteric edema alone was not associated with local pain.     

Diffusion-weighted MR imaging findings of kidneys in patients with early phase of obstruction

Background

Diffusion-weighted (DW) magnetic resonance (MR) imaging is an MR technique used to show molecular diffusion. The apparent diffusion coefficient (ADC), as a quantitative parameter calculated from the DW MR images. The purpose of this study is to evaluate the ability of DW MR imaging in early phase of obstruction due to urolithiasis.

Materials and methods

Twenty-six patients with acute dilatation of the pelvicalyceal system detected by intravenous urography were included in this study. MR imaging was performed using a 1.5 T whole-body superconducting MR scanner. DW imaging can be performed using single-shot spin–echo, echo-planar imaging (EPI) sequences with the following diffusion gradient b values: 100, 600, 1000 s/mm². Circular region of interest (ROI) was placed in the renal parenchyma for the measurement of ADC values in the normal and obstructed kidney. For statistical analyses, Paired t test were used.

Results

In spite of obstructed kidneys had the lower ADC values compared to normal kidneys, these alterations were statistically insignificant.

Conclusion

We did not observe significantly different ADC values of early phase of obstructed kidneys compared to normal kidneys.     

Renal and perirenal space involvement in acute pancreatitis: An MRI study

Objectives

To study the prevalence and characteristics of renal and perirenal space involvement and its relation to the severity of acute pancreatitis (AP) using MRI.

Methods

115 patients with AP who underwent MRI with the clinical kidney function test were retrospectively analyzed in this study. MRI sequences included conventional and diffusion weighted imaging (DWI) sequences. The renal and perirenal space involvement in AP was noted on MRI. The renal apparent diffusion coefficient (ADC) on DWI was measured for each kidney. The severity of AP on MRI was graded using MR severity index (MRSI). The relationships among the renal and perirenal space involvement on MRI, the renal ADC, MRSI and the results of the kidney function test were analyzed.

Results

In the 115 patients with AP, the renal and perirenal space abnormalities detected included renal parenchymal abnormalities (0.8%), abnormalities of the renal collecting system (2.6%), renal vascular abnormalities (1.7%), thickened renal fascia (99%), perirenal stranding (62%) and perirenal fluid collection (40%). The prevalence of perirenal space abnormalities was correlated with the severity of AP based on MRSI (P < 0.05). The renal ADC values were lower in patients with abnormal kidney function than in those without kidney injury (P < 0.05). The prevalence of kidney function abnormalities was 9.4%, 32% and 100% in mild, moderate, and severe AP cases, respectively (P = 0.00).

Conclusion

Perirenal space involvement is much more than renal parenchymal involvement in AP. The prevalence of perirenal space involvement in AP on MRI has a positive correlation with the severity of AP according to MRSI.     

The role of pre-treatment MRI in established cases of slipped capital femoral epiphysis

Background

Slipped capital femoral epiphysis (SCFE) often results in functional impairment and premature osteoarthritis despite surgical treatment. Treatment decisions are commonly based on the clinical history and radiographic appearance. This study assesses the pre-treatment features of SCFE and correlates them to the clinical history to: (1) define the underlying pathological mechanisms; (2) correlate the morphological hip abnormalities with the clinical classifications; (3) identify specific magnetic resonance imaging (MRI) features that could carry prognostic implications for treatment approach and outcome.

Methods

Clinical history and pre- and posttreatment radiographs and pre-treatment MRIs of 14 patients with 15 affected hips were reviewed. Alignment, impingement, fulcrum formation, remodelling, osteopenia, synovitis, joint effusion, bone marrow and soft tissue oedema and status of the physis and the periosteal sleeve were assessed and related to the clinical history, in particular history of trauma, duration of clinical symptoms and ability to bear weight.

Results

Bone marrow oedema around the growth plate and joint effusion occurred in all patients. Synovitis occurred in 13/15 patients. 6 patients had a fall before presenting with SCFE. 5/6 had periarticular soft tissue oedema, complete disruption of the physis and partial periosteal sleeve disruption. 9 patients had no fall prior to presentation, physis and periost were intact in 7/9; periarticular oedema was not seen. 14/15 showed evidence of chronic remodelling. Despite an acute clinical history remodelling was present. A fulcrum-like alignment, impingement of the epiphysis on the metaphysis with a small area of physical contact, was seen in 8 patients, 6/8 had a prior fall. There was no case of avascular necrosis. Spontaneous reduction of SCFE occurred in 1 case, the only case without chronic remodelling. With MRI as gold standard radiographs underestimate the severity of SCFE.

Conclusion

Synovitis, periphyseal oedema and joint effusion are regular features of SCFE. The clinical history and findings are unreliable for the classification of SCFE. Radiographs underestimate the severity of SCFE. SCFE is often a Salter Harris I injury due to a fall with considerable periarticular soft tissue trauma and a potentially unstable alignment of epi- and metaphysis. This can lead to spontaneous reduction prior to surgery, MRI can potentially identify unstable, reducible slips. If the mode of surgical treatment depends on the particular nature of the SCFE then MRI contributes to surgical decision-making.

Level of evidence

Level 4, case series.     

A meta-analysis of common risk factors associated with the diagnosis of developmental dysplasia of the hip in newborns

Background

Although there is no clear consensus about the process of screening for developmental dysplasia of the hip (DDH), there are six common risk factors associated with DDH in patients less than 6 months of age (breech presentation, sex, family history, first-born, side of hip, and mode of delivery).

Methods

A meta-analysis of published studies was conducted to identify the relative risk ratio of the six commonly known risk factors. A total of 31 primary studies consisting of 20,196 DDH patients met the following inclusion criteria: (1) contained empirical data on at least one common risk factor, (2) were peer-reviewed from an English language scientific journal, (3) included patients less or equal to 6 months of age, and (4) identified method of diagnosis (e.g., ultrasound, radiographs or clinical examination).

Results

Fixed effect and random effects models with 95% confidence intervals were calculated for each of the six risk factors. Reported relative risk ratio (RR) for each factor in newborns was: breech presentation 3.75 (95% CI: 2.25–6.24), females 2.54 (95% CI: 2.11–3.05), left hip side 1.54 (95% CI: 1.25–1.90), first born 1.44 (95% CI: 1.12–1.86), and family history 1.39 (95% CI: 1.23–1.57). A non-significant RR value of 1.22 (95% CI: 0.46–3.23) was found for mode of delivery.

Conclusion

Results suggest that ultrasound and radiology screening methods be used to confirm DDH in newborns that present with one or a combination of the following common risk factors: breech presentation, female, left hip affected, first born and family history of DDH.     

Ex vivo MRI of axillary lymph nodes in breast cancer

Purpose

To provide a strategy for precise co-localization of lymph nodes on axillary lymph-node dissection (ALND) specimens both on pathology and MR.To identify nodal features suggestive of metastatic involvement on a node-to-node basis.

Materials and methods

National Institutional review-board approved this prospective study of 18 patients with breast cancer referred for ALND. Ex vivo T1 and inversion recovery (IR) T2 WI of ALND specimens tightly positioned within scaled plastic cranes was performed immediately after surgery. The correspondence of MR-based or pathologically based nodes location was assessed. The MR size and morphological presentation of metastatic and normal nodes were compared (Student's t-test or Mann–Whitney test). Quantitative variables were compared using Pearson coefficient.

Results

207 nodes were retrieved on pathology and 165 on MR. MR–pathological correlation of nodes location was high regarding MR-identified nodes (r = 0.755). An MR short axis threshold of 4 mm yielded the best predictive value for metastatic nodal involvement (Se = 78.6%; Sp = 62.3%). Irregular contours (Se = 35.7%; Sp = 96.7%), central nodal hyper-intensity on IR T2 WI (Se = 57.1%; Sp = 91.4%), and a cortical thickness above 3 mm (Se = 63.6%; Sp = 83.2%) were significantly associated with metastatic involvement.

Conclusion

Ex vivo MR allows node-to-node correlation with pathology. Morphological MR criteria can suggest metastatic involvement.     

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

Objective

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

Methods

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

Results

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

Conclusion

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

Radiographic findings of femoroacetabular impingement in capoeira players

Purpose

Capoeira is a Brazilian martial art that requires extreme movements of the hip to perform jumps and kicks. This study evaluated a group of capoeira players to assess the prevalence of femoroacetabular impingement (FAI) in athletes practicing this martial art.

Methods

Twenty-four experienced capoeira players (14 men, 10 women) underwent a diagnostic assessment, including clinical examination and standard radiographs of the pelvis and hips. The α-angle, head–neck offset, crossover sign, acetabular index, lateral centre-edge angle, and the Tönnis grade were assessed using the radiographs. Clinical relationships for any radiographic abnormalities indicating FAI were also evaluated.

Results

Four subjects (17 %) reported pain in their hips. Forty-four hips (91.7 %) had at least one radiographic sign of CAM impingement, and 22 (45.8 %) had an α-angle of more than 60°. Eighteen hips (37.5 %) had at least one sign of pincer impingement and 16 (33.3 %) a positive crossover sign. Sixteen hips (33.3 %) had mixed impingement. There was a significant positive association between having an α-angle of more than 60° and the presence of groin pain (P = 0.002). A reduced femoral head–neck offset (P < 0.001) and an increased α-angle on the anteroposterior radiograph (P = 0.008) were independently associated with a higher Tönnis grade.

Conclusion

High prevalence of radiographic CAM-type FAI among these skilled capoeira players was found. In these subjects, a negative clinical correlation for an increased α-angle was also detected. Additional caution should be exercised whenever subjects with past or present hip pain engage in capoeira.

Level of evidence

Diagnostic, Level III.     

CT and MR imaging findings of sinonasal angiomatous polyps

Objective

To characterize the CT and MR imaging findings of patients with sinonasal angiomatous polyps (SAPs) and evaluate their respective clinical value in the diagnosis of SAP.

Methods

CT and MR imaging findings of 15 patients with pathologically proven SAP were examined. Assessed image features included location, size, margin, attenuation, and change of the bony walls of the sinonasal cavity on CT, and signal intensity and enhancement pattern on MR.

Results

On CT, the SAP was mostly isoattenuated with patches of slight hyperattenuation. Most lesions caused changes in the adjacent bone, including expansile remodeling (n = 8), defect or destruction (n = 7), and hyperostosis (n = 6). All lesions examined by MR showed heterogeneous isointense signal intensity on T1-weighted images and mixed obvious hyperintense and hypointense signal intensity with linear hypointense septum internally (n = 10), and hypointense peripheral rim on T2-weighted images (n = 10). Postcontrast MR images demonstrated areas of heterogeneous and marked enhancement with an unenhanced hypointense rim and septa (n = 7).

Conclusions

CT and MR imaging have respective advantages in the diagnosis of SAP. Combined application of CT and MR examinations is necessary for patients with suspected SAP.     

Dynamic MR-Mammography as the best method for diagnosis of invasive lobular breast carcinoma: A retrospective study

Aim of the study

It is a retrospective study aiming to provide diagnostic characterization of ILC in Dynamic MR-Mammography and to compare its diagnostic performance to mammography and ultrasonography.

Material and Method

A total of 56 cases of ILC were selected in retrospective review of mammography, ultrasonography and Dynamic MRM of 420 patients with invasive breast cancer.

Results

Asymmetric density was the commonest mammography finding and the measured sensitivity of mammography in detecting ILC was 87.5% (9/56 FN).The most common US manifestation of ILC was focal shadowing without a discrete mass and its sensitivity in detecting ILC was 84.9% (10/56 FN). At MR imaging, the most common manifestation of ILC was a solitary irregular or angular mass with speculated or ill-defined margins (33.9%of cases [n = 19]).The measured sensitivity is 96.5% (2/56 FN). Additional data such as those affected the patient management including the presence of multifocal or multicentric disease, chest wall involvement and contralateral breast cancer were encountered in 48.2% of cases [n = 27]. ILC has a tendency to demonstrate delayed maximum enhancement with washout exhibited by only a minority of lesions (21.4% [n = 12]).

Conclusion

MR imaging has proved to be superior to mammography and US in the detection and management of ILC. It provides useful information for further management and pre-surgical planning.