Single-phase dual-energy CT urography in the evaluation of haematuria

AIM

To assess the value of a single-phase dual-energy computed tomography (DECT) urography protocol with synchronous nephrographic-excretory phase enhancement and to calculate the potential dose reduction by omitting the unenhanced scan.

MATERIALS AND METHODS

Eighty-four patients referred for haematuria underwent CT urography using a protocol that included single-energy unenhanced and dual-energy contrast-enhanced with synchronous nephrographic-excretory phase scans. DECT-based images [virtual unenhanced (VUE), weighted average, and colour-coded iodine overlay] were reconstructed. Opacification degree by contrast media of the upper urinary tract, and image quality of virtual unenhanced images were independently evaluated using a four-point scale. The diagnostic accuracy in detecting urothelial tumours on DECT-based images was determined. The dose of a theoretical dual-phase single-energy protocol was obtained by multiplying the effective dose of the unenhanced single-energy acquisition by two. Radiation dose saving by omitting the unenhanced scan was calculated.

RESULTS

The degree of opacification was scored as optimal or good in 86.9% of cases (k = 0.72); VUE image quality was excellent or good in 83.3% of cases (k = 0.82). Sensitivity, specificity, positive predictive value, and negative predictive value for urothelial tumours detection were 85.7, 98.6, 92.3, and 97.1%. Omission of the unenhanced scan led to a mean dose reduction of 42.7 ± 5%.

CONCLUSION

Single-phase DECT urography with synchronous nephrographic-excretory phase enhancement represents an accurate "all-in-one'' approach with a radiation dose saving up to 45% compared with a standard dual-phase protocol.

Atrial lipomatous hypertrophy causing reduction in systemic venous return

Lipomatous hypertrophy of the interatrial septum (LHIAS) is a benign condition characterized by an abnormal deposition of adipose tissue in the interatrial septum which appears as a pseudomass with a bilobed shape. We present the case of a 68-year-old obese female patient. LHIAS is an infrequent finding, but with recent improvements in imaging it is increasingly recognized. Cardiac MRI may prove useful in its diagnosis in terms of tissue characterization, as well as for the evaluation of disease extension and haemodynamic compromise.

Magnetic resonance cholangio-pancreatography versus endoscopic retrograde cholangio-pancreatography in the diagnosis of common bile duct stones: a prospective comparative study

AIM

As it is a non-invasive method, magnetic resonance cholangiography (MRCP) has almost completely replaced endoscopic retrograde cholangiography (ERCP) in the diagnosis of pancreato-biliary diseases. The aim of this study was to evaluate sensitivity, specificity, diagnostic accuracy, positive predictive value (PPV) and negative predictive value (NPV) of MRCP in diagnosis of choledocholithiasis using ERCP/endoscopic sphincterotomy (ES) as gold standard.

METHODS

For this study 140 individuals, suspected for lithiasis of the common bile duct (CBD), were enrolled. After a clinical and biochemical evaluation, patients underwent upper abdominal ultrasonography, then MRCP and diagnostic and/or operative ERCP.

RESULTS

Only 120 out of 140 patients completed the study. MRCP diagnosed lithiasis of CBD in 84. ERCP confirmed the lithiasis in 73/84 patients who were submitted to ES. Eleven were negative after ES. ERCP documented stones in 10 patients among the 36 negative at MRCP; stones were detected only in four patients after ES. In 26 out of 36 patients negative at MRCP, ERCP confirmed this response: only 12 out of 26 patients underwent ES. The sensitivity, specificity, diagnostic accuracy, PPV and NPV of MRCP were: 88%, 72%, 83%, 87%, 72%.

CONCLUSIONS

As the MRCP diagnostic yield is still limited with small stones, the question of which patient is the best candidate to ERCP/ES is still unsolved.

Smoking, polyuria and impaired vision

The pituitary gland can be involved in a variety of medical conditions, including metastatic tumors. Metastases to the pituitary gland, although absolutely rare, more commonly affect the posterior pituitary lobe and so frequently present with diabetes insipidus. We report on a 48-year-old male heavy smoker patient suffering from sudden onset of polyuria and persistent thirst. Laboratory results revealed central diabetes insipidus. Computed tomography (CT) scan of the brain showed a mass located in the sella turcica and in the suprasellar region. CT scan of the chest showed a mass in the right superior lobe with mediastinal lymphadenopathy, with bronchoscopy and biopsy features of pulmonary adenocarcinoma. The patient received radiotherapy on the pituitary gland and adjuvant chemotherapy, and as intrasellar and suprasellar mass decreased in size, urinary output was accordingly reduced. Therefore, is that in patients with risk factors for cancer and sudden onset of diabetes insipidus pituitary metastasis should be taken into account in differential diagnosis.

Clinical and muscle magnetic resonance imaging study of an Italian family with autosomal dominant inclusion body myopathy not linked to known genetic loci

The objective was to report a clinical, pathological and muscle magnetic resonance (MR) study of an Italian family with an autosomal dominant inclusion body myopathy (AD-IBM). Eight subjects (age range 20-56 years; 5 females and 3 males) belonging to four generations were studied. Onset of disturbances (distal weakness at lower limbs) ranged from 20 to 28 years. CK levels were increased to five times. Only in an early stage oedema of involved muscles has been demonstrated by muscle MR. Quadriceps femoris was characteristically spared; in the last phases a mild involvement of the vasti became evident with persistent sparing of the rectus femori. Rimmed vacuoles and hyperphosphorylated tau filaments were evident at muscle biopsy. Linkage analysis excluded the association of the disease to chromosome loci 14q11, 17p13.1, 2p13, 19p13. The study suggests that quadriceps sparing is a characteristic feature also of AD-IBM. This finding could represent a muscle-image hallmark helpful in diagnosis of autosomal dominant muscular disorders.

Specific matrix metalloproteinase expression in focal myositis: an immunopathological study

OBJECTIVES

The aim of our study was to investigate immunoexpression of matrix metalloproteinases MMP2, MMP7 and MMP9 in muscle specimens from patients with focal myositis (FM) vs polymyositis (PM) and dermatomyositis.

MATERIALS AND METHODS

We studied muscle biopsy samples from seven patients affected by FM; samples from five patients each with PM and dermatomyositis were studied as disease controls.

RESULTS

MMP2 immunoreactivity was present in PM and dermatomyositis, MMP7 only in PM, and MMP9 in PM, dermatomyositis and FM.

CONCLUSIONS

Our results confirm that increased MMP9 immunoreactivity in muscle fibres is a common feature of all inflammatory myopathies and suggest that MMP2 and MMP7 cannot be implicated in the inflammatory events of FM.

Hepatic artery aneurysm, an unusual cause of obstructive jaundice: MR cholangiography findings

Hepatic artery aneurysms are rare vascular lesions, often with a nonspecific clinical presentation, and difficult to diagnose before rupture. We report the case of a patient with obstructive jaundice caused by a compression on the right biliary duct by a right hepatic artery aneurysm in which the diagnosis was suggested by magnetic resonance cholangiography and confirmed by Doppler sonography and preoperative digital subtraction angiography.

Computed tomography features of liparitosis: a pneumoconiosis due to amorphous silica

The purpose of this study was to describe the radiological features of pleural, parenchymal and mediastinal damage due to occupational inhalation of pumice. In total, 31 workers were evaluated for annual follow-up. Spiral computed tomography (CT) was obtained in the three patients with evident parenchymal abnormalities at chest radiograph. High-resolution computed tomography (HRCT) was performed in the remaining 28 subjects with no radiographical evidence of pleuropulmonary damage or evidence of pleural plaques, in order to exclude parenchymal involvement. Pumice samples were analysed by radiograph diffraction and scanning electron microscopy. Spiral CT showed parahilar conglomerate masses containing fine reticular calcifications in three of 31 (9.7%) patients. HRCT showed several bilateral pleural plaques, without any parenchymal lesion in eight of 28 (28.6%) cases. Statistical analysis indicated correlation between CT findings and pulmonary function, as well as exposure to pumice. The analysis of pumice excluded the presence of asbestos. The findings from this study suggest that pleural plaque may be the only sign of disease in patients with a history of pumice inhalation. However, conglomerate parahilar masses are probably due to exposure to massive amounts of heated pumice, and seem to have different pathogenesis and histopathological characteristics to silicosis.

Low-pathogenicity avian influenza virus in live bird markets--what about the livestock area?

Low-pathogenic avian influenza virus (AV) continues to be isolated from the live bird markets (LBMs) in the Northeasten United States. Recent years have seen increasing numbers of these markets opening and an expansion of the type of animals they sell in conjunction with traditional live poultry. Specific-pathogen-free chickens were released into the livestock area of 13 New York City LBMs and then tested for evidence of AIV. We were able to recover virus or demonstrate seroconversion among the chickens introduced to four of the markets.

MR pyelography in the assessment of hydroureteronephrosis: single-shot thick-slab RARE versus multislice HASTE sequences

BACKGROUND

We used magnetic resonance (MR) pyelography to compare the value of thick-slab single-shot rapid acquisition with relaxation enhancement (RARE) sequence with that of multislice half-Fourier acquisition single-shot turbo-spin-echo (HASTE) sequence in evaluating the full spectrum of morphologic features in a group of patients with hydronephrosis.

METHODS

MR pyelographic images, with the use of thick-slab RARE and multislice HASTE sequences in 90 patients, were evaluated for image quality, presence of hydronephrosis, and level and cause of obstruction.

RESULTS

HASTE sequences provided images of better quality than did RARE sequences (p < 0.001). There was no statistically significant difference in demonstrating the presence of hydronephrosis (p = 0.5) and level of obstruction (p = 0.125). Sensitivity, specificity, and accuracy in diagnosing cause of obstruction were 61.7%, 62.5%, and 62%, respectively, for RARE sequences and 80%, 82.5%, and 81%, respectively, for HASTE sequences, with a statistically significant difference (all p < 0.05).

CONCLUSION

Multislice HASTE sequence provides better diagnostic information than does thick-slab RARE sequence, particularly in evaluating the cause of obstruction.

Contrast-enhanced MR imaging with fat suppression in adult-onset septic spondylodiscitis

Spinal infections typically involve vertebrae as well as discs, and for this reason they are called septic spondylodiscitis. Magnetic resonance imaging is the most sensitive imaging method for the evaluation of this group of spinal diseases. The use of contrast-enhanced T1-weighted sequences with fat suppression, if correctly applied, may increase information provided by MRI. Firstly, this technique allows the primary vertebral focus, which often precedes disc involvement, to be identified at a very early stage. When the disease spreads, T1-weighted fat-suppressed gadolinium dimeglumine (Gd-DTPA) enhanced images provide macroscopic details of the primary vertebral focus, disc involvement patterns, and pathways of infection diffusion. All this information, when correlated with laboratory tests, may be useful in identifying the infectious agents (tuberculous vs piogenic forms), thus enabling a suitable therapy to be started. This technique is also useful in the assessment of the real extension of the disease, providing a clear depiction of paravertebral space involvement and of psoas muscle abscesses. Dangerous complications, such as meningitis, myelitis, and epidural abscesses, may be more promptly diagnosed and fully evaluated with fat-suppressed post-contrast T1-weighted images. Finally, this imaging technique may help to differentiate infectious processes from degenerative disorders, extradural neoplastic processes, and rheumatic diseases.

Contrast-enhanced power Doppler US in the diagnosis of renal pseudotumors

The term "pseudotumor" is used to refer to several anatomic variants that can simulate a renal mass, the most frequent of which are hypertrophied column of Bertin, persistence of fetal lobation, and the dromedary or splenic hump. We describe the findings of power Doppler US after the ultrasound contrast agent (Levovist, Schering, Berlin, Germany) administration in 4 patients with a renal focal lesion in whom gray-scale and baseline power Doppler US was not able to certainly differentiate pseudotumor from neoplasm.

Twisted ovarian fibroma with high signal intensity on T1-weighted MR image: a new sign of torsion of ovarian tumors?

Torsion of ovarian tumors is often difficult to diagnose, because of non-specific clinical, laboratory, and imaging findings. We report a case of twisted ovarian fibroma whose main characteristic was the presence of large areas of high signal intensity on both T1- and T2-weighted MR images due to the passive congestion of the mass. This previously unreported finding should be considered a sign of ovarian torsion and may facilitate prompt surgical intervention.