Apparent diffusion coefficients of sacroiliitis in patients with established ankylosing spondylitis.

AIM: To compare apparent diffusion coefficients (ADCs) of sacroiliac joints (SIJs) in ankylosing spondylitis (AS) patients during advanced-active and advanced-nonactive stages. MATERIALS-METHODS: AS patients with chronic-active (n=19), chronic-nonactive (n=6), and controls with normal SIJs (n=8) were included. Mean ADCs through 43 subchondral bone marrow edema lesions (SBMELs) were calculated. RESULTS: Mean ADCs were 1.60+/-0.32 × 10-3 mm(2)/s over SBMELs, 0.57+/-0.23 × 10-3 mm(2)/s at periphery of SBMELs, 0.57+/-0.24 × 10-3 mm(2)/s in chronic-nonactive group, and 0.61+/-0.19 × 10-3 mm(2)/s for controls. CONCLUSION: ADCs lower than 0.69 × 10-3 mm(2)/s, obtained at subchondral aspect of SIJs of established AS patients with chronic changes, which this number represents the receiver operating characteristic (ROC) best cutoff value, can be considered as normal without possible residual inflammation of concern.

Value of DWI in visual assessment of activity of sacroiliitis in longstanding ankylosing spondylitis patients.

OBJECTIVE: To test contrast to noise ratios (CNRs) of both diffusion-weighted (DW) images and contrast enhanced images in terms of the visual assessment of activity in sacroiliitis of ankylosing spondylitis (AS) patients. MATERIALS AND METHODS: The study included 21 patients with AS. All patients were examined with STIR, FST1/Gd and DWI (b = 0,600). A total of 54 hyperintense lesions on STIR were noted in their sacroiliac joints divided into four quadrants. CNRs were calculated for all of the sequences above. A second group of patients (n = 7) with normal sacroiliac joints (SIJs) served as controls. A total of 56 CNR measurements from apparently normal subchondral bone marrow in this control group were done as well. The differences between scores were tested for significance (SPSS version 17.0) using Wilcoxon's test in which p values lower than 0.01 were considered statistically significant. RESULTS: In the first group with sacroiliitis, mean CNRs for STIR, FST1/Gd, DWI were 32.97, 30.16 and 24.47, respectively. Mean CNRs in the second group with normal SIJs were calculated as 3.52 , 2.99 and 3.96, respectively . There was a statistically significant difference between the CNR measurements of the first and the second group (p = 0.000). Hyperintense lesions on STIR were depicted as "active" in the first group. Except for four lesions that were not included into the study, all of these hyperintense lesions were enhanced after contrast media administration. All of the "active" lesions were observed on DWI as well, at b = 600. No statistically significant difference between CNRs of contrast enhanced images and DWI and of contrast enhanced images and fluid sensitive sequences were found in the first group with sacroiliitis (p > 0.01). CONCLUSION: The CNRs are highest on STIR, followed by contrast enhanced images and DWIs. In terms of DWI and contrast enhanced images, there is no statistically significant difference between these two. Hence, contrast enhanced imaging can be replaced by DWI for visual analysis of active sacroiliitis, which is easy to apply without adverse affects of contrast media.

Is there any relation between distal parameters of the femur and its height and width?

The purpose of this study was to reveal the association whether the distal morphometry of femur had a relation with femur height or width. Sixty-six adult (35 right and 31 left) dry femurs from Caucasians were used in this study. Computed tomography (CT) imaging was applied to obtain measurement values of the femur. Femur height (413.29 ± 28.40 mm) and width (29.86 ± 2.72 mm) were all checked one by one to determine the correlation with the parameters obtained. Both values exposed high rates of correlation with height (26 ± 2.34 mm) and width (20.85 ± 2.76 mm) of femur notch; also, measures of epicondylar, bicondylar and condylar diameters of femur were obtained. Measures were checked if there was a correlation with femur height and width. Differences displayed in distal morphometry of femur according to race and sex are due to other morphometric measures of femur rather than race and sex. We believe that displaying the high rates of correlation of distal morphometry of femur with femur height and width will be the factor which determines the selection and production of prosthesis among the long or short individuals of folks.

Onycho-pachydermatit with extensive bone marrow edema predominant in the metacarpals: a "forme fruste" of POPP?

Psoriatic onycho-pachydermo-osteo/periostitis (POPP) syndrome is a rare form of psoriatic arthritis with a combination of (i) psoriatic onychodystrophy, (ii) connective tissue thickening, and (iii) periostitis of the distal phalanges. The treatment of the condition has generally been reported to be unsatisfactory with the traditional regimes. Here, we describe a case whom we believe is one presentation of POPP with extensive bone marrow edema of metacarpal bones without distinctive periostitis.

Pediatric abdominal masses: diagnostic accuracy of diffusion weighted MRI.

PURPOSE: To retrospectively identify apparent diffusion coefficient (ADC) values of pediatric abdominal mass lesions, to determine whether measured ADC of the lesions and signal intensity on diffusion-weighted (DW) images allow discrimination between benign and malignant mass lesions. MATERIALS AND METHODS: Approval for this retrospective study was obtained from the institutional review board. Children with abdominal mass lesions, who were examined by DW magnetic resonance imaging (MRI) were included in this study. DW MR images were obtained in the axial plane by using a non breath-hold single-shot spin-echo sequence on a 1.5-T MR scanner. ADCs were calculated for each lesion. ADC values were compared with Mann-Whitney U test. Receiver operating characteristic curve analysis was performed to determine cut-off values for ADC. The results of visual assessment on b800 images and ADC map images were compared with chi-square test. RESULTS: Thirty-one abdominal mass lesions (16 benign, 15 malignant) in 26 patients (15 girls, 11 boys, ranging from 2 days to 17 years with 6.9 years mean) underwent MRI. Benign lesions had significantly higher ADC values than malignant ones (P < .001). The mean ADCs of malignant lesions were 0.84 +/- 1.7x10(-3) mm2/s, while the mean ADCs of the benign ones were 2.28 +/- 1.00x10(-3) mm2/s. With respect to cutoff values of ADC: 1.11x10(-3) mm2/s, sensitivity and negative predictive values were 100%, specificity was 78.6% and positive predictive value was 83.3%. For b800 and ADC map images, there were statistically significant differences on visual assessment. All malignant lesions had variable degrees of high signal intensity whereas eight of the 16 benign ones had low signal intensities on b800 images (P < .001). On ADC map images, all malignant lesions were hypointense and most of the benign ones (n=11, 68.7%) were hyperintense (P < .001). CONCLUSION: DW imaging can be used for reliable discrimination of benign and malignant pediatric abdominal mass lesions based on considerable differences in the ADC values and signal intensity changes.

Prolapsing ectopic ureterocele presenting as a vulval mass in a newborn girl.

Prolapse of the ureterocele and its presentation as a vulval mass is an extremely rare condition. There are no detailed imaging findings of such cases in the literature. We present voiding cystourethrography and MRI findings of a newborn girl with a ureterocele extending through the urethra.

Dysembryoplastic neuroepithelial tumors: proton MR spectroscopy, diffusion and perfusion characteristics.

INTRODUCTION: We describe the magnetic resonance (MR) imaging characteristics of dysembryoplastic neuroepithelial tumors (DNT) and discuss their differential diagnosis. MATERIAL AND METHODS: Proton MR spectroscopy (TE 30 and 136 ms), diffusion-weighted and perfusion images were retrospectively evaluated in 22 patients with pathologically proven DNT (17 male and 5 female, mean age 18.7 years) and 14 control subjects (10 male and 4 female, mean age 16.9 years). The results from the DNT patients and from the control subjects were compared using an independent sample t-test and the degree of correlation was tested by Pearson's correlation. RESULTS: All DNTs were solitary and in a supratentorial cortical or subcortical location (ten temporal, eight frontal and four parietal). They had low-signal on T1-weighted images and high-signal on T2-weighted images without a prominent mass effect. Additionally a cystic appearance (six patients, 27.3%), cortical dysplasia (six patients, 27.3%) and contrast enhancement (four patients, 18.2%) were also noted. No significant differences were detected in NAA/Cho, NAA/Cr, NAA/Cho+Cr or Cho/Cr ratios between DNT and normal brain. DNTs had a significantly higher mI/Cr ratio and apparent diffusion coefficient (ADC) values and lower cerebral blood values than normal parenchyma (P < 0.001). ADC had the highest correlation with the diagnosis of DNT (r = 0.996) followed by relative cerebral blood volume (rCBV) (r = -0.883) and mI/Cr ratio (r = 0.663). CONCLUSION: Proton MR spectroscopy, diffusion-weighted and perfusion imaging characteristics of DNTs provide additional information to their MR imaging findings. The MR spectrum showing a slight increase in mI/Cr ratio, and higher ADC and lower rCBV values than normal parenchyma help to differentiate DNTs from other cortical tumors, which had higher rCBV and lower ADC values than DNTs.

High-resolution CT findings in patients with pulmonary tuberculosis: correlation with the degree of smear positivity.

BACKGROUND: There are data about the relationship between morphologic findings on high-resolution computed tomography (HRCT) and the number of acid-fast bacilli (AFB) on sputum smears in patients with pulmonary tuberculosis (PTB). It was also shown that existence of cavities and airspace consolidation might be related to smear positivity in PTB patients. However, there is no study suggesting a relationship between AFB on sputum smears and radiologic extent of disease based on HRCT findings. AIM: In this study, we investigated a relationship between the degree of smear positivity and radiologic extent of disease based on HRCT findings and, the degree of smear positivity and different pulmonary parenchymal changes on HRCTs of the PTB patients. METHODS: Sixty-one male patients with PTB (mean age: 22+/-3.2) were included into the study. HRCT images were assessed for patterns, distribution, and profusion of pulmonary abnormalities. Dividing the lungs into 3 zones, profusion of abnormalities was assessed. A profusion score was given. Patients were divided as smear positive and smear negative and compared for the scores of HRCT findings. Smear-positive patients were divided into 4 groups as per grading of the sputum AFB smear: group I (sputum 1+), group II (sputum 2+), group III (sputum 3+), and group IV (sputum 4+). Correlations were investigated between the degree of smear positivity and the scores of HRCT findings. RESULTS: A significant correlation between radiologic extent of the disease based on HRCT and the degree of smear positivity was found (r=0.63, P=0.0001). There were also significant correlations between the degree of smear positivity and the scores of different HRCT findings. Nodule, cavity, and bronchial lesions are the most important contributors of the predictive properties of the total score. There was significant differences for the scores of HRCT findings between smear-positive and smear-negative patients. CONCLUSIONS: Our study suggests that radiologic extent of disease based on HRCT findings in patients with PTB correlated with the degree of smear positivity. Different HRCT findings such as nodule, cavitation, ground-glass opacity, consolidation, and bronchial lesion are significantly associated with smear-positive PTB. Particularly, nodules, cavities, and bronchial lesions might be predictors of smear positivity in patients with PTB. This study also suggests that the thickness of cavity wall and the distance of cavity from central airways might be related to the degree of smear positivity.

Imaging features of benign adrenal cysts.

Benign adrenal gland cysts (BACs) are rare lesions with a variable histological spectrum and may mimic not only each other but also malignant ones. We aimed to review imaging features of BACs which can be helpful in distinguishing each entity and determining the subsequent appropriate management.

Intravenous contrast-enhanced dynamic MR urography: diagnosis of vesicoureteral reflux during bladder filling with time-signal intensity curves.

PURPOSE: To evaluate the time-signal intensity (SI) curves generated from intravenous (IV) gadodiamide-enhanced dynamic magnetic resonance (MR) urographic scans for identifying vesicoureteral reflux (VUR) during bladder filling. MATERIALS AND METHODS: MR urographic studies of children were retrospectively reviewed, and 52 ureterorenal units of 26 patients (15 females and 11 males, mean age = 5.5 years) who had also undergone voiding cystourethrographic (VCUG) examination were included in this study. The patients were examined on a 1.5T scanner. For functional MR urography and to generate time-SI curves, we used a post IV contrast-enhanced two-dimensional (2D) fast field echo (FFE) sequence (TR = 17 msec, TE = 3.2 msec, flip angle (FA) = 90 degrees ) in the coronal plane. MR urographic time-SI curves that demonstrated a prompt and concave fall of the initial third phase followed by intermittent or constantly increasing SI peaks above the baseline from which the second phase starts were considered to have VUR. We compared the differences in time-SI curves between the control group and patients with VUR during bladder filling. RESULTS: Twelve ureterorenal units of eight patients (four bilateral and four unilateral) had VUR during bladder filling on VCUG. The time-SI curves of these patients showed intermittent (N = 8 ureterorenal units), and constantly increasing (N = 4 ureterorenal units) SI peaks consistent with VUR. One patient also had bilateral abnormal time-SI curves suggesting VUR despite the normal VCUG study. In the control group, 25 units had normal triphase time-SI curves, six renal units had urinary dilatation with good washout after diuretic injection, and four renal units had upper urinary dilatation without contrast washout, while five renal units did not show any function. None of the patients in the control group revealed distortion in the time-SI curve. The differences in time-SI curves patterns between the control group and patients with VUR during bladder filling were statistically significant (P < 0.001). CONCLUSION: After a prompt and concave decrease of the initial third phase of the time-SI curve, intermittent spikes or a constant rise in SI above the baseline suggest the existence of VUR.

MR urography in pediatric uropathies with dilated urinary tracts.

PURPOSE: To determine the diagnostic value of magnetic resonance (MR) urography in children with urinary tract dilatation. MATERIALS AND METHODS: Twenty-five children between the ages of 4 months and 13 years (19 males and 6 females, mean age 6.5 years) were evaluated with T2 weighted and contrast-enhanced T1 weighted MR sequences. Results were compared with findings obtained with ultrasonography (n=25), intravenous urography (n=18), Tc99m- DTPA scintigraphy (n=16), and/or micturating cystouretrography (n=13). RESULTS: MR urography provided a superior imaging of urinary system dilatation, the site and the etiology of obstruction, and both regular and complicated kidney duplication than did conventional imaging methods. MR urography that used T2 weighted sequences was able to demonstrate 29 of 32 (90.6%) abnormal renal collecting systems. Fourteen of 21 (66.7%) normal systems were revealed by heavily T2 weighted images. Forty-six of 51 (90.2%) renal collecting systems could be shown by T1 weighted sequences. With this sequence, however, five collecting systems (9.8%) could not be shown secondary to poor renal function and/or dilution of contrast agent within the dilated urinary tract. CONCLUSION: In children, MR urography may replace conventional uroradiological methods.

Assessment of diagnostic accuracy of perfusion MR imaging in primary and metastatic solitary malignant brain tumors.

PURPOSE: The purpose of this study was to estimate the diagnostic accuracy of relative cerebral blood volume (rCBV) measurement in preoperative grading and differentiation of solitary intra-axial malignant brain tumors. METHODS: Thirty-six low-grade glial tumors (LGGTs), 22 high-grade glial tumors (HGGTs), and 17 metastases (METs) were prospectively evaluated by MR imaging and standard dynamic susceptibility contrast-enhanced gradient echo, echoplanar imaging during first pass of a bolus injection of contrast material. Normalized rCBV values from tumoral (rCBV(T)) and peritumoral (rCBV(P)) areas were calculated by standard software and statistically tested independently. RESULTS: The mean differences of rCBV(T) and rCBV(P) values between LGGT (2.30 +/- 1.12 and 1.18 +/- 0.24) and HGGT (5.42 +/- 1.52 and 2.17 +/- 0.82) (P < .001); HGGTs and METs (3.21 +/- 0.98 and 0.97 +/- 0.09) (P < .001); and LGGTs and METs (P < .05 and P < .001, respectively) were significant. No clear cutoff value was present. A clear rCBV(T) cutoff value of 2.6 was detected for differentiation of low- (1.75 +/- 0.38; LGA) versus high-grade (4.78 +/- 0.99; HGA) astrocytomas when nonastrocytic glial tumors were excluded. The rCBV(T) values were linearly correlated with degree of malignancy (r = 0.869; P < .001). Cutoff rCBV(P) values of 1.1 and 1.2 were quite effective in differentiation of METs from LGGTs and HGGTs, respectively. The overall efficacy of rCBV was higher in grading than in differentiation. CONCLUSION: The diagnostic accuracy of rCBV measurement is higher in grading of glial brain tumors than in differentiation of HGGTs from solitary intra-axial METs. The astrocytic and nonastrocytic glial tumors have to be evaluated separately for precise grading.

The added value of the apparent diffusion coefficient calculation to magnetic resonance imaging in the differentiation and grading of malignant brain tumors.

OBJECTIVE: ADC calculation can improve the diagnostic efficacy of MR imaging in brain tumor grading and differentiation. METHODS: Apparent diffusion coefficient (ADC) values and ratios of 33 low-grade (23 astrocytomas, 10 oligodendrogliomas) and 40 high-grade (25 metastases and 15 high-grade astrocytomas) malignant tumors were prospectively evaluated. RESULTS: Tumoral ADC values (r=-0.738, P <0.000) and ratios (r=-0.746, P < 0.000) were well correlated with higher degree of malignancy and quite effective in grading of malignant brain tumors (P < 0.000). By using cutoff values of 0.99 for tumoral ADC value and 1.22 for normalized ADC ratio, the sensitivity of MR imaging could be increased from 72.22% to 93.75% and 90.63%, the specificity from 81.08% to 92.68% and 90.24%, PPV from 78.79% to 90.91% and 87.88%, and NPV from 75.00% to 95.00% and 92.50%, respectively. CONCLUSION: ADC calculation was quite effective in grading of malignant brain tumors but not in differentiation of them and added more information to conventional contrast-enhanced MR imaging.

Imaging findings in idiopathic granulomatous mastitis. A review with emphasis on magnetic resonance imaging.

OBJECTIVE: To describe magnetic resonance (MR) imaging features of patients with a histologic diagnosis of idiopathic granulomatous mastitis (IGM). METHODS: Dynamic contrast-enhanced MR imaging was performed with a 1.5-T MR unit. Postprocessing of images included subtraction and calculation of time-intensity curves of the enhancing regions at several points in all patients. RESULTS: In addition to granulomatous inflammation, biopsy slides of 5 patients demonstrated abscess formation without a specific organism (aseptic abscess). One patient had a fibrotic tissue component. Magnetic resonance imaging findings were heterogeneously enhancing areas with (n = 5) and without (n = 1) multiple ring-like enhanced abscesses and a circumscribed lesion with heterogeneous contrast enhancement (n = 1). Time-intensity curves showed a benign pattern in all but 1 patient. CONCLUSION: Idiopathic granulomatous mastitis has a number of appearances on MR imaging. Magnetic resonance imaging with measurement of time-signal intensity curves may support the findings of ultrasonography and mammography in distinguishing benign inflammatory breast disorders from malignant ones; however, biopsy still remains the only method of definite diagnosis.

Tolosa-Hunt syndrome with heterotopic salivary gland tissue and absence of internal carotid artery.

Tolosa-Hunt syndrome (THS), heterotopic salivary gland and hypoplasia of internal carotid artery (ICA) are all rare entities. We have reported a case of all these three conditions included in a patient. We have postulated that the heterotopic salivary gland tissue might have caused the hypoplasia of ICA and also triggered the THS.

Value of magnetic resonance imaging in the depiction of intravenous leiomyomatosis extending to the heart.

Intravenous leiomyomatosis is a seldom neoplasia characterized by invasion of venous channels by a benign smooth muscle tumor originating either from a uterine myoma or from vessel wall. Extension to the heart may cause mechanical obstruction and is frequently misdiagnosed as a right-atrial myxoma. We present a case of recurrent intravenous leiomyomatosis with previous hysterectomy because of uterine leiomyoma which have different magnetic resonance characteristics than that of the former reports.

A different approach to missile induced head injuries.

Missile induced head injuries can be influenced by the anatomical location of the injury, i.e. type of tissue and by the ballistic properties such as the design of the weapon and the mass, shape and construction of the projectile, as well as its velocity characteristics and trajectory angle. In the diagnostic work up of the patients with missile induced head injuries, every available modality can be used. It is important, however, to recognize that CT scan is the primary and most efficacious diagnostic tool in such patients. In this article we have identified risk factors for both morbidity and mortality in patients with missile induced head injury with excluding the patients who had also extracranial serious trauma and systemic disease.

Combination of single-voxel proton MR spectroscopy and apparent diffusion coefficient calculation in the evaluation of common brain tumors.

BACKGROUND AND PURPOSE: MR spectroscopy and apparent diffusion coefficient (ADC) calculation have been used frequently for tumor grading and differentiation during the last decade. We evaluated whether the combination of these two techniques can improve the diagnostic effectiveness of MR imaging in patients with brain tumors. METHODS: Forty-nine patients with histologically proved brain tumors (eight high- and 12 low-grade astrocytomas, eight metastases, eight nonastrocytic gliomas, seven meningiomas, three dysembryoplastic neuroepithelial tumors (DNETs), and three tuberculomas) were prospectively evaluated with contrast material-enhanced MR imaging, single-voxel proton MR spectroscopy (TE = 135 ms), and diffusion-weighted imaging (b = 0, 500, and 1000 s/mm(2)) before surgery. RESULTS: MR spectroscopy could differentiate benign from malignant tumors but was not useful in grading malignant tumors. In the differentiation of malignant from benign tumors, N-acetylaspartate (NAA)/choline (Cho), NAA/Cho + creatine (Cr), lactate/Cr, and alanin/Cr ratios (P <.001) were statistically more significant than NAA/Cr and lactate/lipid ratios (P <.05). Increase in lipid/Cr and alanin/Cr ratios could distinguish metastasis and meningiomas from other tumors, respectively (P <.001). DNETs could be diagnosed by their normal spectra and high ADC values (116.25 +/- 6.93 x 10(-3) mm(2)/s). Increase in lactate/Cr ratio correlated with degree of malignancy (r = -0.71). ADCs were effective for grading malignant tumors (P <.001) but not for distinguishing different tumor types with the same grade. High-grade malignant tumors (87.16 +/- 10.41 x 10(-3) mm(2)/s) had significantly lower ADC values than did low-grade malignant (115.33 +/- 11.67 x 10(-3) mm(2)/s) and benign (107.69 +/- 8.05 x 10(-3) mm(2)/s) tumors. Peritumoral ADCs were significantly higher in low-grade than in high-grade astrocytomas (P <.05). CONCLUSION: Combination of calculated ADC values from tumoral core and specific relative metabolite ratios acquired by MR spectroscopy added more information to MR imaging in the differentiation and grading of brain tumors and were more useful together than each alone.