Pulmonary congenital cystic disease in adults. Spiral computed tomography findings with pathologic correlation and management.

PURPOSE: The aim of this study was to assess the computed tomography (CT) features of intrapulmonary congenital cystic diseases in adults and to correlate the imaging features with the pathological findings, with emphasis on the oncogenic potential of the lesions. MATERIALS AND METHODS: We retrospectively reviewed the CT scans in three institutions from August 1996 to December 2008, of nine patients (six men, three women; mean age 48.6 years; range 26-75 years) who had histological diagnosis of pulmonary cystic disease after surgery. Six patients had a diagnosis of intrapulmonary bronchogenic cyst (IBC), and three had a type-I cystic adenomatoid malformation (CAM). In one case, intralobar sequestration (ILS) was associated with type-I CAM. RESULTS: Three patients were symptomatic and six were asymptomatic. On CT scans, IBCs showed homogeneous fluid attenuation (n=2), air-fluid level (n=2), air attenuation (n=1) or soft-tissue attenuation (n=1). The surrounding lung tissue showed areas of band-like linear attenuation in three IBCs, atelectasia in two and mucocele-like areas in one. On CT, type-I CAM appeared as a unilocular cystic lesion with air-fluid level (n=1) or air content (n=1). Both cases had thin walls surrounded by normal lung parenchyma. ILS appeared as a fluid-filled cyst with afferent and efferent vessels. Of the six IBCs, one occurred in the upper right lobe, two in the middle lobe and three in the lower right lobe. Of the three type-I CAMs, one was in the upper left lobe and one in the middle lobe. The type-I CAM associated with ILS was located in the left lower lobe. CONCLUSIONS: The similar CT patterns preclude differentiation between IBC and type-I CAM. Surgical resection of all intrapulmonary cystic lesions detected in adults is mandatory because type-I CAM is a precursor of mucinous bronchioloalveolar carcinoma.

Small (< or = 2 cm) atypical hepatic haemangiomas in the non-cirrhotic patient: pattern-based classification scheme for enhancement at triple-phase helical CT.

PURPOSE: The aim of this study was to determine by triplephase helical computed tomography (CT) the appearance of atypical small (< or = 2 cm) hepatic haemangiomas (HHs) in the non-cirrhotic patient. MATERIALS AND METHODS: We retrospectively reviewed the hepatic arterial-dominant phase (HAP), portal venous phase (PVP) and delayed-phase (DP) helical CT images of 47 patients with 52 atypical small (< or = 2 cm) HHs associated with 34 typical small HHs. Images were assessed to identify the patterns of enhancement of atypical HHs and correlate their appearance with that of typical small HHs in the delayed phase. Interobserver variability and kappa value were calculated. Statistical significance was calculated by the Fisher exact test. RESULTS: The 52 atypical small HHs were categorised as follows: type 1a (hyperattenuating in the HAP, n=17), type 1b [hyperattenuating with transient hepatic attenuation difference (THAD) around the lesion in the HAP, n=12], type 2a (homogeneously hypoattenuating in the HAP or PVP, n=9), type 2b (hypoattenuating with "bright-dot" sign in the HAP or PVP, n=13) and type 3 (hypoattenuating with central enhancing area, n=1). Interobserver agreement was perfect for HHs of types 1a, 1b, 2a and 3. On DP images, the appearance of atypical small HHs was identical to that of typical small HHs in all cases (p<0.0001), with lesions showing homogeneous isoattenuation to the aorta or liver parenchyma without peripheral capsule. CONCLUSIONS: Triple-phase helical CT scans can distinguish several types of atypical small HHs. The demonstration of patterns similar to those of typical forms on DP CT is fundamental for the diagnosis.

CT angiography versus colour-Doppler US in acute dissection of the vertebral artery.

PURPOSE: Conventional digital subtraction angiography (DSA) still represents the criterion standard for the diagnosis of vertebral artery dissection (VAD), but the main drawbacks of this technique include invasiveness, patient discomfort and risk of complications. We evaluated the potential of multidetector computed tomography angiography (CTA) as a noninvasive tool providing high-resolution images of the arterial lumen and wall by comparing the diagnostic accuracy of CTA and colour-Doppler ultrasonography (CDUS) in detecting acute VAD. MATERIALS AND METHODS: We retrospectively reviewed 15 cases of VAD in 15 patients (five men and ten women, age range 28-58 years) who came to our attention between August 2001 and September 2005. The diagnosis was made on the basis of appropriate clinical presentation, absence of atherosclerotic disease in the cerebrovascular circulation and evidence of distinctive CT features, which were subsequently confirmed by conventional angiography used as reference standard. All patients with a clinical suspicion of VAD underwent CDUS of the neck vessels prior to CTA. Accuracy, sensitivity and specificity of CDUS and CTA were expressed as percentages of agreement with the reference angiographic procedure. Interreader concordance for detection of VAD by CTA was calculated with the Cohen K value. RESULTS: The CDUS examinations revealed ten out of 15 VAD, with a sensitivity of 66%, a specificity of 60%, a positive predictive value of 55.5% and a negative predictive value of 70.5%. In five cases, CDUS revealed nonspecific wall and flow alterations; in eight patients, high resistance obstructive flow; and in two patients, intimal flap with demonstration of the true and false lumen. CTA enabled the correct identification of all 15 VAD. The reported sensitivity, specificity, positive predictive value and negative predictive value were 100%, 95%, 93.7% and 100%, respectively. With regard to localisation of VAD, CTA showed 100% correlation with DSA. The differences in CTA and CDUS sensitivity (100% vs 66%), specificity (95% vs 60%), and overall diagnostic accuracy (97% vs 62.8%), assessed by cross tabulations and compared by using the McNemar's two-sided test, were significant (p<0.05). CONCLUSIONS: Multidetector CTA is a sensitive technique for the diagnosis of VAD. Used as a complement to unenhanced brain CT, it has the advantage of being readily available and easy to perform.

Three-dimensional analysis of pulmonary nodules by MSCT with Advanced Lung Analysis (ALA1) software.

PURPOSE: The purpose of this study was to test the reproducibility of the three-dimensional (3D) Advanced Lung Analysis software (3D-ALA, GE Healthcare) in the estimation of pulmonary nodule volume. MATERIALS AND METHODS: We retrospectively reviewed the unenhanced multislice CT scans (Lightspeed Pro 16 GE) of 77 patients with a solitary pulmonary nodule (n=71) or metastatic pulmonary disease (n=6). A total of 103 pulmonary nodules (19 well-circumscribed, 45 juxtavascular and 39 juxtapleural) were analysed grouped into five classes based on diameter: <5 mm, 10 nodules (9.7%); >or=5 to <10 mm, 25 nodules (24.2%); >or=10 mm to <15 mm, 41 nodules (39.8%); >or=5 to <18 mm, 14 nodules (13.6% ); >or=8 to <30 mm, 13 nodules (12.62%). The following acquisition parameters were used: slice thickness 0.625 mm, reconstruction interval 0.4 mm, pitch 0.562:1, 140 kV, 300 mAs, field of view 13 cm, bone kernel. For each of the 103 nodules three, 3D volume measurements were obtained by the 3D-ALA software. The reproducibility of nodule segmentation was evaluated according to a visual score (1=optimal, >or=95%; 2=fair, 90-95%; 3=poor, 0.05). CONCLUSIONS: Three-dimensional volume measurement with ALARiassunto 1 software is reproducible for all nodules as regards dimension and site. ALA-1 software provided a good and reproducible volume measurement in well-circumscribed and most juxtavascular nodules. Volumetric evaluation and reproducibility of volume estimation in juxtapleural pulmonary nodules, particularly those adjacent to diaphragmatic pleura, is inadequate, and software improvement is needed.

Emergencies in the retroperitoneum: assessment of spread of disease by helical CT.

Acute pancreatitis, leaking abdominal aortic aneurysm, and renal trauma frequently occur in the setting of patients with abdominal nontraumatic and traumatic injury; it represents the most urgent conditions that may determine the presence of fluid collections or haematoma in the retroperitoneum. Single spiral CT and multidetector-row CT (MDCT) play an important role in diagnosis of retroperitoneal emergencies, providing useful informations on the type, site, extent and management of the fluid collections. An accurate CT assessment requires the awareness of the existence of dissectable retroperitoneal fascial planes. Fluid collections or haematoma tends to escape the retroperitoneal site of origin into planes extend from the diaphragm to the pelvic floor. We assess the multicompartimental anatomy of the retroperitoneum and the pathway of spread of the most frequent retroperitoneal fluid collections or haematoma by helical CT.

Does gender influence outcome of AAA endoluminal repair?

BACKGROUND: It has been suggested that female patients have a less favourable outcome of endoluminal repair of abdominal aortic aneurysms. Yet, data on stratified per gender are lacking. METHODS: We reviewed our prospective database of 402 endografts over a 4-year period and the peri- and postoperative course in the 25 (6%) female patients was compared with the 377 (94%) male patients. Median follow-up was 24 months (range 1-56 months). Logistic regression analysis was performed to test the effect of five confounding variables (gender, age, ASA grade IV, EUROSTAR class D or E, AAA diameter) on failure of AAA exclusion. RESULTS: There were no perioperative deaths in the female group and 5 (1.3%) in the male group (p = 0.8). Major perioperative morbidity occurred in 17% versus 6% (OR 3.7; 95% CI 1.2-10.6; p = 0.026). There were 1 (4%) and 5 (1%) conversions to open repair in the female and male groups, respectively (p = 0.3). Late failure of AAA exclusion occurred in 5 (21%) and 26 (7%) patients, respectively (p = 0.03). Of the five variables examined for their influence on failure of AAA exclusion, female gender (hazard ratio 4.42; 95% CI 1.4-13.4; p = 0.009) and AAA diameter (hazard ratio 1.05; 95% CI 1.009-1.09; p = 0.017), were positive independent predictors of late failure of AAA exclusion on multivariate analysis. CONCLUSION: Endoluminal AAA repair in female patients appear associated with a less favorable outcome when compared to their male counterparts. These data may be taken into consideration when endoluminal AAA repair is suggested to a female patient.

Chronic iliac artery occlusion: treatment with the Strecker stent after PTA.

The purpose of this retrospective study was to evaluate the use of percutaneous transluminal angioplasty (PTA) and subsequent. Strecker stent implantation for the treatment of chronic iliac artery occlusions. A total of 39 patients were subjected to this procedure. The occluded vessels were catheterized, dilated and subjected to stenting in all patients: the length of occlusion varied from 4.5 to 10.5 cm (mean 5.9), lesions were located in common iliac arteries (25), external iliac arteries (10) and in combinations of both (4). Twenty-five patients presented stage II according to Fontaine classification, nine patients stage III and five patients stage IV. The stent was mounted on balloon catheter and introduced through a 9 French sheet (for 8-10 mm stent diameter). After this procedure, 37 out of 39 patients showed a statistically significant increase in the Doppler sonographic ankle-arm index (AAI) (P = 0.001) and improvement of clinical symptoms, while in two patients a complete occlusion resulted due to long dissection not covered by the stent in one case and to stent misplacement in the other case. After stenting, 27 patients improved to stage I, ten patients to stage IIa and two patients showed no changes. Two complications were observed: one groin hematoma and one distal embolization. At a 6-month follow-up, a 89.7% of patency was observed. This study shows that Strecker stent can be successfully employed in addition to PTA to treat occlusions of the iliac arteries.

Percutaneous transluminal angioplasty in the treatment of chronic mesenteric ischemia: results and 3 years of follow-up in 23 patients.

BACKGROUND: We evaluated the clinical efficacy of visceral angioplasty in the treatment of chronic mesenteric ischemia. METHODS: Over a 14-year period, we performed percutaneous transluminal angioplasty of 41 occlusive diseases of visceral arteries founded by angiography in 23 patients with chronic mesenteric ischemia. All but one (fibrodysplasic) stenoses were atherosclerotic, and 13 were localized in the ostial tract. Clinical follow-up was evaluated at 2, 6, 12, 24, and 36 months (mean follow-up = 27 months). RESULTS: Angioplasty demonstrated a residual stenosis of 30% or less in 37 procedures, for a technical success rate of 90%. Seventeen of 20 patients had symptom remission after the first treatment, for a short-term clinical success of 77%; two patients needed a reangioplasty after 2 months, and one was referred for aortomesenteric bypass. During a mean follow-up of 27 months (range = 2-36), the clinical success was 88%; 2/15 patients underwent successful repeat angioplasty at 24 and 36 months, for a 100% secondary long-term clinical success. Only two minor complications were encountered. CONCLUSION: Although surgical results are undoubtedly positive, visceral angioplasty is justified in relation to both the high surgical mortality and the low incidence of complications arising from visceral angioplasty.

MR study of N2 disease in lung cancer: contrast-enhanced method using gadolinium-DTPA.

OBJECTIVE: In several previous studies, including one of our own, CT and MRI provided similar information on N2 detection in the staging of lung cancer. Both imaging techniques can be considered effective in detecting enlarged mediastinal lymph nodes but the results are often inaccurate when confronted with pathological findings. The purpose of this study was to assess the diagnostic accuracy of gadolinium-DTPA enhanced MRI in the detection of mediastinal lymph nodes in lung cancer. METHODS: A prospective study to compare standard unenhanced MRI and Gd-DTPA enhanced MRI was carried out in patients with diagnosed lung cancer. The study focused on the status of mediastinal lymph nodes. Gd-DTPA was administered at a dosage of 0.2 mmol2/KG before T1 weighted sequences. Qualitative visual analyses of both standard and contrast enhanced MRI images were performed on each patient by 2 independent radiologists. The imaging results were then compared to pathological findings obtained after surgical operation. RESULTS: In the identification of mediastinal lymph node metastases standard MRI was 62% sensitive, 100% specific and 74% accurate whereas Gd-DTPA enhanced MRI was 100% sensitive, 91% specific and 97% accurate. CONCLUSIONS: Gd-DPTA enhanced MRI was more accurate than standard MRI in the detection of metastatic lymph nodes in patients with lung cancer. These initial results can be considered encouraging especially with regards to the reduction of false negative findings although further confirmation is, understandably, required.

MRI postoperative monitoring in patients surgically treated for aortic dissection.

In most cases, surgery of aortic dissections repairs only the ascending portion of the aorta, leaving a residual dissection in the arch and descending aorta. We studied 17 patients operated upon for type A aortic dissection. A total of 42 magnetic resonance imaging (MRI) examinations were performed, with two to five studies per patient (mean 2.47). The studies were done between 5 weeks and 47 months (mean 17.5 months) after surgery. The patients were evaluated by MRI using gated spin-echo and gradient-echo sequences on axial and oblique sagittal views, and in selected cases, coronal views. A high incidence of abnormalities was observed. Pericardial hematoma was observed in 11% of cases, aortic and branch involvement in 41%, abdominal aortic branch involvement in 47%, dilatation of native aorta in 58%, and extension of dissection in 10%. New complications were detected during follow-up in 53% of patients. MRI was helpful in the follow-up of patients operated upon for aortic dissections, owing to its noninvasiveness and multiplanarity. By means of this technique, it was possible to obtain information about the natural history of the disease, as well as information useful for subsequent treatment.

[Carcinoma of the pancreas. Typical and atypical aspects using midfield-strength magnetic resonance]. / Carcinoma del pancreas. Aspetti tipici e atipici con Risonanza Magnetica con media intensità di campo.

Until few years ago, MR assessment of pancreatic carcinoma was thought to be feasible only with high-strength equipment, but today also low- and midfield units allow pancreatic lesion detection, thanks to parameter optimization. The authors retrospectively analyzed the MR findings of 57 patients examined with a midfield MR unit; all the patients had clinically suspected pancreatic carcinoma, which was confirmed in 54 cases. The lesions were more easily detected using T1-weighted sequences, thanks to their high intrinsic contrast, while T2-weighted sequences often confirmed the glandular changes already depicted by T1-weighted sequences. MRI correctly depicted vascular and lymph node involvement and detected liver metastases with no i.v. contrast agent injection. The only limitations of this technique are the unfeasibility of MR exams of diagnostic value in uncooperative patients (5% of cases) and the very similar MR features of parenchymal scars, due to previous acute pancreatitis, to those of pancreatic carcinoma. In conclusion, CT remains the gold standard in the study of pancreatic cancers, but midfield strength MRI, if correctly performed, can be proposed as a complementary tool to CT, especially in questionable cases and in the patients with known reactions to iodinated contrast agents.

Clinical outcome of orthopaedic patients with negative lower limb venography at discharge.

Pharmacological prophylaxis for postoperative venous thromboembolism is generally restricted to the hospital stay. A high incidence of deep vein thrombosis (DVT) and pulmonary embolism presenting after hospital discharge has been reported and thus it has been claimed that pharmacological prophylaxis should be continued after discharge. The aim of this study was to perform a prospective survey to assess the prevalence of clinically overt thromboembolic events in hip surgery patients discharged with a negative venography without further pharmacological prophylaxis. We followed-up 213 patients with negative venography at discharge (105 elective hip replacement and 108 hip fracture patients). 186 patients (87.3%) were re-examined as outpatients one to two months after discharge. Five patients reported symptoms of DVT but the diagnosis was not confirmed by objective testing. The remaining 27 patients (12.7%) were followed up through their family doctor or by telephone call; in these patients the follow-up period ranged from 60 days to 2 years. Twenty-two patients (10.3%) were still alive and reported no signs or symptoms of venous thromboembolism. Three patients (1.4%) died for reasons not correlated with venous thromboembolism. Two patients could not be traced due to geographical inaccessibility; they were still alive after 1 year according to the records of their health care district. The results of our study suggest that in hip surgery patients with negative venography the prevalence of clinically overt thromboembolic events after hospital discharge ranges from 0 to 2.2% (95% C.I.). It is conceivable that the majority of late presenting postoperative DVT actually develop during the hospital stay and become symptomatic after hospital discharge.

Low-field magnetic resonance imaging in the evaluation of mechanical and biological heart valve function.

Magnetic resonance imaging (MRI) has been frequently considered unsafe for patients with ferromagnetic implants: risks to be considered include induction of electric current, heating and dislocation of the prosthesis. Previous in vitro and in vivo studies have indicated the possibility of performing MRI examinations on patients with prosthetic heart valves. The aim of our study was to verify the presence of artifacts at the level of the prosthetic heart valve in vivo using a low-field MR unit (0.2 T) and to define the possibility of a functional analysis of the valve in patients with biomedical or mechanical prostheses. We evaluated 14 patients surgically treated for implantation of nine biological and seven mechanical aortic and mitral valves. A low-field MR unit (0.2 T) was employed using cine-MR technique on long- and short-axis view. The images were acquired on planes parallel and perpendicular to the valvular plane. Semiquantitative analysis with double-blind evaluation for definition of the extent of the artifact was performed. Three classes of artifacts were distinguished from minimal to significant. The examinations showed the presence of minimal artifacts in all biological heart valves and moderate artifacts in mechanical valves giving good qualitative data on blood flow near the valve. Analysis of the flow behind the valve showed signs of normal function in 13 prostheses and pathological findings in the remaining three. In these latter cases, MRI was able to define the presence of a pathologic aortic pressure gradient, mitral insufficiency and malpositioning of the mitral valve causing subvalvular turbulence. Nevertheless, we believe that the application of velocity-encoding cine-MR is more promising than semiquantitative analysis of artifacts.

[Magnetic resonance in the study of inflammatory diseases of the pancreas]. / La Risonanza Magnetica nello studio delle malattie infiammatorie del pancreas.

The role of diagnostic imaging modalities in pancreatic inflammatory diseases is to assess gland damage and peripancreatic tissue involvement. The artifacts related to breathing and to peristaltic movements can be partially resolved with the optimization of acquisition parameters, which allows MRI to be suggested for the assessment of pancreatic inflammatory conditions. Sixty-nine patients with pancreatic inflammatory diseases (20 acute and 49 chronic pancreatitis cases) were examined. MRI was performed with a 0.5-T superconductive magnet and T1- and T2-weighted spin-echo (SE) sequences. In 4 of 20 acute pancreatitis patients image quality was poor. MRI in acute pancreatitis demonstrated glandular edema, intraparenchymal necrosis and the extent of peripancreatic fluid collections; in chronic pancreatitis MRI depicted glandular atrophy and Wirsung duct dilatation and detected the presence of pseudocysts. Even though its spatial resolution is lower than that of CT, MRI can provide useful pieces of information in inflammatory diseases of the pancreas, much more so after the introduction of Fast SE sequences and of fat-saturation techniques which are likely to make MR examinations of the pancreas more widely used.

[Technologic advances in magnetic resonance imaging: permanent low-field magnets dedicated to the study of the joints. Clinical results]. / Innovazioni tecnologiche nella Tomografia con Risonanza Magnetica: magneti permanenti con basso campo dedicati allo studio articolare. Risultati clinici.

Magnetic Resonance Imaging (MRI) has had a significant impact on the diagnosis of musculoskeletal conditions. Technologic advances in the last years allowed the development of cost-effective, compact and easy-to-install MR systems. After an early phase to optimize the units, a 14-month multicentric study was performed to define the possible clinical applications of the system. The obtained data are reported by the authors in the present study to assess the diagnostic accuracy of the new MR system for the study of the limbs. The system consists of an 0.2 T permanent unit, weighting 800 Kg, with a built-in radiofrequency shield and 10 mT/m gradients. October, 1992, to February, 1994, 2437 limbs examinations were carried out in patients whose age ranged 5 to 83 years. In 93% of cases, the exam was performed to study one joint, mostly the knee. MR diagnosis was verified in 311 patients, who were subsequently submitted to surgery. Quite satisfying overall results were obtained, particularly in case of knee traumas, comparable to those provided by units with more potentials. The particular structure of the magnet allowed the comfortable management of the pediatric, aged and acute patients. Nevertheless, in 3% of the investigated knee or elbow conditions, the examinations could not be performed due to technical limitations related to magnet size. In addition, the authors believe that a limited field of view (11-16 cm) does not allow accurate staging of the malignant lesions involving soft tissue and bone, which require a wider locoregional staging.

Does postcontrast MR enhancement in lumbar disk herniation have prognostic value?

OBJECTIVE: The aim of our study was to evaluate the prognostic value, if any, of Gd-enhanced MR in patients with lumbar disk herniation. MATERIALS AND METHODS: Fifteen patients undergoing conservative treatment for acute lumbar disk herniation were included in a prospective Gd-DTPA follow-up MR study. In each patient, the size of the herniation was measured, and, according to the changes in pathology that occurred, patients were divided into four categories. In addition, on the basis of the clinical outcome patients were divided into three classes. RESULTS: In 11 of 15 patients, MR performed in the acute phase of the disease showed Gd-DTPA enhancement around the herniated disk; in all cases, disk herniation was markedly reduced at follow-up MRIs. The clinical outcome was good. In the remaining four cases, no enhancement was evident in the acute phase or at follow-up MRIs; no modification in the size of disk herniation was demonstrated at follow-up in two. Symptoms were unchanged in two patients and mildly improved in one. CONCLUSION: Epidural enhancement, which is likely related to an inflammatory process, seems to play a role in the modification of the size of disk herniation.

[The magnetic resonance imaging of abdominal aortic aneurysms]. / L'imaging con Risonanza Magnetica degli aneurismi dell'aorta addominale.

The diagnostic role of Magnetic Resonance Imaging (MRI) was investigated in the study of abdominal aortic aneurysms and compared with that of Computed Tomography (CT) and digital subtraction angiography (DSA). Magnetic Resonance angiography (MRA) was performed on 21 patients with radiologically proved abdominal aortic aneurysms, using a superconductive 1.5 T magnet (GE, Signa Advantage); the 2D TOF technique with gradient-echo sequences was used (SPGR: FA 45-60 degrees, TR/TE 33/7, ST 2 mm, 1 nex, 256 x 128 matrix, inferior presaturation and flow compensation). The images acquired on the axial plane were reconstructed according to MIP and rotated on the z-axis from +90 degrees to -90 degrees. In all cases SE 2D T1- and T2-weighted sequences were acquired on the axial plane. Twelve patients were examined with MRI, CT and DSA; 3 with MRI and CT; 2 with MRI and DSA and finally 4 with MRI only. The radiologic studies were then reviewed blind and the results of the different methods compared. In all cases MRI yielded similar information to CT and DSA as to aneurysm extent and size, vessel involvement, status of visceral, iliac and common femoral arteries and finally the conditions of perianeurysmatic tissues. The authors conclude that MRI is a useful and accurate technique for the preoperative examination of abdominal aortic aneurysm patients.

Stress MR imaging for evaluation of popliteal artery entrapment.

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young health volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.

[Characterization of hypertrophic cardiomyopathy with magnetic resonance]. / Caratterizzazione della cardiomiopatia ipertrofica con risonanza magnetica.

We selected 15 patients with hypertrophic cardiomyopathy (HCM) and 5 with secondary myocardial hypertrophy (SMH). All patients were examined by means of Magnetic Resonance Imaging (MRI) and echocardiography. The MR study was performed with gated T1- and T2-weighted spin echo sequences and cine MRI. We correlated echocardiographic and MRI measurements and found a correlation coefficient (R) of 0.72 for apex thickness, r = 0.84 for posterior wall thickness, 0.76 for the lateral wall and 0.89 for the area at papillary level. Cine MR acquisitions showed signal loss in the systolic phase at the outflow tract in 9 obstructive HCM patients, which was consistent with echocardiographic color Doppler findings. The signal intensity of myocardial tissue was analyzed with MRI. The values were correlated with those of the skeletal muscle. We performed the paired sample t-test on T1- and T2-weighted spin echo sequences between the signal at the septum and that of the free wall in the 15 HCM patients. The analysis showed significant differences on T2-weighted sequences (p < 0.02). Unpaired t-test was performed between the 15 HCM and the 5 SMH patients; the analysis showed significant differences on both T1- (p < 0.01) and T2-weighted sequences (p < 0.04).