Giacomo Garlaschi

Dynamic magnetic resonance of the wrist in psoriatic arthritis reveals imaging patterns similar to those of rheumatoid arthritis

This dynamic magnetic resonance imaging (MRI) study is concerned with a prospective evaluation of wrist synovitis in patients with psoriatic arthritis (PsA) in comparison with patients with rheumatoid arthritis (RA) and healthy controls. Fifteen consecutive patients with PsA, 49 consecutive patients with RA, 30 RA patients matched for disease severity with those with PsA, and 8 healthy controls were studied. MRI was performed with a low-field (0.2T), extremity-dedicated machine. After an intravenous bolus injection of gadolinium-diethylenetriaminepentaacetic acid, 20 consecutive fast spin-echo axial images of the wrist were obtained every 18 s. The enhancement ratio was calculated both as rate of early enhancement (REE), which shows the slope of the curve of contrast uptake per second during the first 55 s, and as relative enhancement (RE), which indicates the steady state of enhancement. The REE was 1.0 ± 0.6 in patients with PsA, 1.6 ± 0.7 in consecutive patients with RA, and 0.1 ± 0.1 in controls (p <0.001). The RE was 87.1 ± 39.2 in patients with PsA, 125.8 ± 48.0 in consecutive RA patients, and 15.5 ± 19.2 in controls (p <0.001). However, the same figures in matched RA patients were 1.3 ± 0.7 and 107.3 ± 48.2, respectively (not significant in comparison with PsA). Rheumatoid-like PsA and oligoarticular PsA did not differ from each other in terms of synovial enhancement. Dynamic MRI shows the same pattern of synovitis in patients with PsA and RA when the two groups are matched for disease severity. This technique cannot be used to differentiate PsA from RA. However, REE and RE were significantly higher in PsA than in normal controls, with only one instance of overlap between values found for the two groups.

Multidetector computed tomography arthrography of the knee: diagnostic accuracy and indications.

PURPOSE To evaluate the diagnostic accuracy and indications of arthrography with multidetector computed tomography (arthro-MDCT) of the knee, in patients with absolute or relative contraindications to MRI and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. MATERIALS AND METHODS After intra-articular injection of iodixanol and volumetric acquisition, 68 knees in patients of both sexes (30 females, 38 males, age range 32-60 years) were examined with a 16-detector-row CT scanner. The patients had arthralgia but no radiologically detected fractures. They could not be studied by MRI either because of absolute contraindications (subcutaneous electronic implants), surgical metal implants or claustrophobia. In 37 of 68 patients who had had previous knee surgery, the arthro-CT examination was preceded by an MRI on the same day. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. RESULTS In non-operated patients the comparison between arthro-MDCT and arthroscopy showed sensitivity and specificity ranging between 86% and 100%. In the 37 operated knees, arthro-MDCT had an accuracy of 95% compared with 53% of the MRI. Inter-observer agreement was almost perfect (K=0.97) in the evaluation of all types lesions, both on MDCT and MRI. When arthro-MDCT was compared with MRI in post-operative patients by a McNemar test, a significant difference (p<0.05) was found between these two techniques. CONCLUSIONS Arthro-MDCT of the knee is a safe technique that provides accurate diagnosis in identifying chondral, fibrocartilaginous and intra-articular ligamentous lesions, in patients that cannot be evaluated by MRI, and in patients after surgical.

Pancreatic Schwannoma : report of three cases

We report the computed tomography findings in three cases of pancreatic schwannoma and discuss the differential diagnosis versus other cystic appearing pancreatic masses.

Brain apparent diffusion coefficient evaluation in pediatric patients with neurofibromatosis type 1

Objective: The most frequent intracranial appearance in children with neurofibromatosis type 1 (NF1) is represented by the presence of hyperintense lesions on T2-weighted images, the so-called “unidentified bright objects” (UBOs). Di Paolo demonstrated that these lesions represent foci of myelin vacuolization with increased water content. The aim of this study was to investigate the isotropic apparent diffusion coefficient (ADC) values within the UBOs and normal-appearing brain and at the regressed UBO sites. Methods: Fifteen consecutive children with NF1 underwent magnetic resonance diffusion evaluation of the brain. Fifteen healthy age- and sex-matched children constituted the control group. Apparent diffusion coefficient maps were obtained, and regions of interest were placed bilaterally in 8 different areas. Two cortical areas were evaluated using single-pixel analysis. Apparent diffusion coefficient values within the UBOs were calculated by using irregular regions of interest. Regressed UBO sites were investigated by using circular regions of interest. Apparent diffusion coefficient values within the different areas were compared using a t test. Results: Compared with the controls, NF1 patients showed higher ADC values (P < 0.001) in all locations. In the NF1 group, the mean ADC value in the UBOs was higher than in other locations (P < 0.001). The mean ADC value within the regressed UBO sites was higher than in the normal-appearing locations (P < 0.001). Conclusions: The higher ADC values in children with NF1 suggest an increase in water content of the normal-appearing brain. The UBOs are the areas with the highest water content. The regressed UBOs sites show higher water content than the normal-appearing areas.

Congenital anomalies and variations of the bile and pancreatic ducts: magnetic resonance cholangiopancreatography findings, epidemiology and clinical significance

PurposeThe objective of this paper is to document the magnetic resonance cholangiopancreatography (MRCP) findings and the epidemiology of congenital anomalies and variations of the bile and pancreatic ducts and to discuss their clinical significance.Materials and methodsThree-hundred and fifty patients of both sexes (150 females, 200 males, age range 0–76 years, average age 38 years) underwent MRCP for clinically suspected lithiasic, neoplastic or inflammatory disease of the bile and pancreatic ducts. Patients were imaged with a 1.5-T superconductive magnet (Magnetom Vision, Siemens, Erlangen, Germany), a four-channel phased-array body coil, breath-hold technique, with multislice T2-weighted half-Fourier acquisition single-shot turbo spin echo (HASTE), MIP reconstructions, and a single-shot T2-weighted turbo-spin-echo sequence rapid acquisition with relaxation enhancement (RARE) with different slice thicknesses. Studies in oncological patients were completed with fat saturation 3D T1 gradient-echo sequences during the intravenous injection of gadolinium diethylene triamine pentaacetate acid (DTPA) (0.2 ml/kg).ResultsMRCP demonstrated recurrent and therefore normal bile and pancreatic ducts in 57% of patients. In the remaining 42.3%, it documented anatomical variants (41%) and congenital anomalies (1.3%). Variants of the intrahepatic bile duct were seen in 21% of cases: crossover anomaly (6.7%), anterior branch of the right hepatic duct draining the IV and VII segments that flow together with the left bile duct (3.1%) and anterior and posterior branches of the right hepatic duct that flow together with the common hepatic duct (3.3%). Variants of the extrahepatic bile ducts were present in 8.8% of patients: low insertion of the cystic duct into the common hepatic duct (4.5%), emptying of the cystic duct into the right hepatic duct (2.7%) and a second-order large branch draining into the cystic duct (1.6%). MRCP identified a double gall bladder in 3% of patients and anatomical variants of the biliopancreatic system in 8.2%: pancreas divisum (5.2%) and a long sphincter of Oddi (3%). Finally, congenital anomalies were diagnosed in 1.3% of cases: bile duct cysts (0.3%), atresia of the bile ducts (0.3%) and multiple biliary hamartomatosis (0.7%).ConclusionsThe congenital anomalies and anatomical variants of the bile and pancreatic ducts present a complex spectrum of frequent alterations, which are worthy of attention in both the clinical and surgical settings and are readily identified by MRCP.RiassuntoObiettivoDocumentare gli aspetti colangiopancreato-RM (CPRM), valutare l’epidemiologia e discutere il significato clinico delle varianti e delle anomalie congenite delle vie biliari e pancreatiche.Materiali e metodiTrecentocinquanta pazienti di entrambi i sessi (150 F e 200 M; range di età 0-76 anni, età media 38 anni) sono stati sottoposti a CPRM per i sospetti clinici di patologia litiasica, neoplastica e flogistica delle vie biliari e pancreatiche. È stato impiegato un magnete superconduttivo da 1,5 T con bobina body phased-array a quattro canali, tecnica breath-hold, acquisizioni half-fourier con T2-W (HASTE) multislice, ricostruzioni MIP, e single shot T2-W turbo-spin-echo (RARE) con differente spessore di strato. Alcuni esami, in pazienti oncologici, sono stati completati con sequenze gradient echo 3D T1w fat-sat durante somministrazione in vena periferica di mezzo di contrasto gadolinium-DTPA (0,2 ml/kg).RisultatiLa CPRM ha documentato vie biliari e pancreatiche ricorrenti e pertanto considerate normali nel 57,7% dei pazienti; nel restante 42,3% ha rilevato varianti anatomiche (41%) ed anomalie congenite (1,3%). Nel 21% dei casi le varianti interessavano le vie biliari intraepatiche: crossover anomaly (6,7%), dotto bisegmentario anteriore destro confluente nel dotto biliare di sinistra (3,1%), dotto bisegmentario posteriore destro confluente nel dotto epatico sinistro (7,9%) e nel dotto epatico comune (3,3%). La presenza di varianti anatomiche delle vie biliari extraepatiche è stata riscontrata nell’8,8% dei pazienti: bassa inserzione del dotto cistico nel dotto epatico comune (4,5%), sbocco del dotto cistico nel dotto epatico destro (2,7%), grosso ramo di secondo ordine drenante nel dotto cistico (1,6%). La CPRM ha identificato un 3% di pazienti con colecisti doppia ed un 8,2% di pazienti con varianti anatomiche del sistema bilio-pancreatico: pancreas divisum (5,2%) e sfintere di Oddi lungo (3%). Infine anomalie congenite sono state diagnosticate nell’1,3% dei casi: cisti coledocica (0,3%), atresia delle vie biliari (0,3%) ed amartomatosi biliare multipla (0,7%).ConclusioniLe anomalie congenite e le varianti anatomiche delle vie biliari e pancreatiche costituiscono uno spettro complesso di frequenti alterazioni, documentabili agevolmente in CPRM e meritevoli di attenzione in ambito sia clinico sia chirurgico.

Primary liver leiomyosarcoma: CT appearance

Abstract. Primary hepatic leiomyosarcomas are exceedingly rare tumors. To the best of our knowledge, only 17 cases have been reported in literature. We report the computed tomographic findings of two cases of primary location in the liver. We also discuss the differential diagnosis of such lesions.

Multidetector Computed Tomography Arthrography of the Shoulder: Diagnostic Accuracy and Indications

Background: The presence of subcutaneous implants, such as permanent defibrillators, is an absolute contraindication to the use of magnetic resonance imaging (MRI). Moreover, MRI is unadvisable in subjects with metallic hardware near the area of study, as artifacts generated by such materials distort image quality. Purpose: To evaluate the diagnostic accuracy and indications of arthrography with multidetector computed tomography arthrography (arthro-MDCT) of the shoulder in patients with absolute or relative contraindications to MRI and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Material and Methods: After intraarticular injection of iodixanol and volumetric acquisition, 70 shoulders in 70 patients (30 females, 40 males, age range 32–60 years) were examined with a 16-detector-row CT scanner. The patients had arthralgia but no radiologically detected fractures. They could not be studied by MRI because of absolute contraindications (subcutaneous electronic implants), surgical metal implants, or claustrophobia. In 28 of the 70 patients who had had previous shoulder surgery, the arthro-CT examination was preceded by an MRI on the same day. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In the 42 non-operated patients, the comparison between arthro-MDCT and arthroscopy showed sensitivity and specificity ranging between 87% and 100%. In the 28 operated shoulders, arthro-MDCT had an accuracy of 94% compared with 25% with MRI. Interobserver agreement was almost perfect (κ=0.95) in the evaluation of all types of lesions, both on MDCT and MRI. When arthro-MDCT was compared with MRI in the postoperative patients by a McNemar test, a significant difference (P<0.05) was found between these two techniques. Conclusion: Arthro-MDCT of the shoulder is a safe technique that provides accurate diagnosis in identifying chondral, fibrocartilaginous, and intraarticular ligamentous lesions in patients who cannot be evaluated by MRI, and in patients after surgery.

Thin-section ct follow-up of metastatic ovarian carcinoma correlation with levels of CA-125 marker and clinical history

Second-look laparotomy and CA-125 are the gold standard in follow-up of ovarian carcinoma. Since no definite role seems established for cross-sectional imaging in assessment of recurrence we employed thin-section computed tomography (CT), correlated with CA-125 levels and detailed knowledge of the clinical history as a follow-up protocol One hundred seventy-seven patients with ovarian carcinoma were selected because of: (a) pathologically proven remission after first-line chemotherapy, (b) follow-up by means of thin-section CT every 6 months for the fist 3 years and every 10 months subsequently, (c) monitoring CA-125 serum levels every 3 months for the first 3 years and every 6 months subsequently; (d) pathologic confirmation or clinical and laboratory follow-up after 12 months or longer for the CT findings. Fifty percent of the patients showed recurrence of disease. Our protocol yielded 93.2% true positive, dubious findings in 5.6% 1.0% false negatives, 97.7% true negative, and 2.3% false positive. With a tailored technique, CT was particularly sensitive in early diagnosis of peritoneal seeding, even in the absence of ascites or increases in the levels of CA-125. Repeated administration of contrast medium, water enemas, and repeated scanning of suspicious volumes with differing scanning parameters were the factors managed by the radiologist. We conclude that thin-section CT, correlated with CA-125 levels and careful review of the clinical history could represent a valid alternative to repeated explorative laparotomies in the follow-up of ovarian carcinomas.

Comparison of the manual and computer-aided techniques for evaluation of wrist synovitis using dynamic contrast-enhanced MRI on a dedicated scanner

OBJECTIVE Traditional methods for assessment of synovial inflammation in rheumatoid arthritis such as clinical examination, immunohistology of bioptic samples, scintigraphy, and radiography have several limitations, including lack of sensitivity, need of invasive techniques, and administration of radioactive material. MRI lacks on standardisation and the data are often analysed using laborious, relatively rigid scoring methods. MATERIALS AND METHODS This study introduces a standardized computer-aided method for quantitative analysis of MRI of the wrist on a dedicated scanner. Assessment of the synovial inflammation was performed using a semi-automated model-based method in conjunction with patient motion reduction algorithms. Further, the new method was compared with the traditional user-dependent ROI-based technique. RESULTS The computer-aided technique generated robust and reproducible results. Application of motion reduction algorithms allowed for significant improvements of the signal to noise ratio, which is especially important in the datasets acquired with low-field scanners. CONCLUSION The use of the computer software can be beneficial for diagnostic decision in cross sectional as well as longitudinal MRI examinations of the wrist in rheumatoid arthritis.

Gastric liposarcoma: CT appearance

Two cases of liposarcoma of the stomach are described. At computed tomography (CT) the neoplasms showed features of an aggressive malignant tumor, with no fatty values within. We discuss the differential diagnosis of such lesions and conclude that, although rare, liposarcoma should be considered as a possible diagnosis when a large exophytic gastric mass is detected at CT.