Real-time risk stratification of patients with acute pulmonary embolism by grading the reflux of contrast into the inferior vena cava on computerized tomographic pulmonary angiography.

OBJECTIVE: To investigate whether fast grading of reflux of contrast to the inferior vena cava (IVC) on computerized tomographic pulmonary angiography (CTPA) is a potential biomarker for real-time risk stratification. METHODS: We retrospectively identified 343 patients investigated for possible pulmonary embolism (PE) by CTPA at our medical center between September 2004 and March 2006. A total of 145 consecutive patients with PE (age 67 +/- 19 years) and 168 consecutive ones with negative CTPAs (age 64 +/- 20 years) fulfilled entry criteria. CTPAs were evaluated for retrograde reflux of contrast to the IVC by fast visual grading from 1 to 6 using the original axial images. Pulmonary obstruction index, the diameters of right and left ventricles and pulmonary artery, and patient survival data were recorded as well. RESULTS: Twenty-nine (20.0%) patients with positive CTs and 23 (13.7%) patients with negative CTs had substantial degrees (>or=4) of reflux of contrast to the IVC (P = 0.14). The Kaplan-Meier 30-day survival curves demonstrated significant reduction in survival in individuals with PE and grade >or=4 reflux of contrast to the IVC compared with lower grades (P = 0.008), but not in patients with grade >or=4 and no PE on CTPA (P = 0.26). The other cardiovascular parameters showed no significant correlation with survival in patients with and without PE. CONCLUSION: Substantial grades of reflux of contrast to the IVC during CTPA could predict early mortality in patients with acute PE. Rapid grading of reflux of contrast from the original axial CTPA images can be used for real-time risk stratification in patients with acute PE.

Thoracic outlet syndrome: a multidisciplinary problem with a perspective for microsurgical management without rib resection.

BACKGROUND: Thoracic outlet syndrome (TOS) refers to a group of complex symptoms in the upper extremity caused by compression of the brachial plexus, subclavian artery and vein. Different surgical approaches were described for the management of TOS. There is, however, no "gold standard" procedure for this complicated and multidisciplinary problem. OBJECTIVES: This study evaluated the effectiveness of a microsurgical neurovascular decompression in the treatment of TOS. METHODS: 11 patients suffering from TOS (for 1.3 to 15 years after the beginning of the symptoms) were selected for a treatment of the complex symptoms of pain (diffuse or irradiated to the arm and hand), aching or paresthesia in the neck, shoulder, anterior chest, upper extremity and hand. Four of the 11 patients were suffering from signs of vascular compression. Eight patients showed slow progressive neurological deterioration (distribution of the ulnar nerve) with partial muscle atrophy. Patients underwent a microsurgical treatment using a supraclavicular approach followed by brachial plexus neurolysis, scalenectomy and release of the subclavian artery and vein without rib resection. Postoperative results were classified, using Am. J. Surg. (176: 215-218, 1998) scale (4), as good, fair and poor. RESULTS: Surgical results were studied, with a follow-up of 24 to 48 months. Prior to surgery, all patients had partial or severe limitation in physical activities. Post-operative follow-up showed that 9 (82%) of the 11 patients returned to normal everyday physical activities with a complete or significant relief of the symptoms (good results). In 2 patients (18%) the pain decreased and the use of medication was reduced (fair results). Eight of the 11 patients returned to full or partial employment. There were no cases of poor results in the study. CONCLUSION: Microsurgical neurovascular decompression of TOS without a removal of the cervical or first rib using a supraclavicular approach is an effective treatment method for a relief or complete release from symptoms and allows most patients to return to an active normal life.

High b-value diffusion imaging of dementia: application to vascular dementia and alzheimer disease.

Alzheimer's disease (AD) and Vascular Dementia (VaD) are the most common types of dementia and are progressive diseases affecting millions of people. Despite the high sensitivity of MRI to neurological disorders it has not thus far been found to be specific for the detection of either of these pathologies. In the present study high b-value q-space diffusion-weighted MRI (DWI) was applied to VaD and AD. Controls (N=4), VaD patients (N=8) and AD patients (N=6) were scanned with high b-value DWI, which emphasizes the water component which exhibits restricted diffusion. VaD patients were found to present major WM loss while, in AD, the major pathology found was GM changes, as expected. Also, WM changes in VaD and AD were of a different pattern, more specific to frontal and temporal areas in AD and more widespread in VaD. This pattern of WM changes may be utilized as a diagnosis criterion. Conventional diffusion tensor imaging did not show significant changes between either of the groups and controls. These results demonstrate the potential of high b-value DWI in the diagnosis of dementia.

Diagnosis of intrathoracic lesions: are sequential fine-needle aspiration (FNA) and core needle biopsy (CNB) combined better than either investigation alone?

AIM: To assess the diagnostic accuracy of sequential computed tomography (CT)-guided percutaneous fine-needle aspiration (FNA) and core-needle biopsy (CNB) in comparison with FNA and CNB performed separately for diagnosing intrathoracic lesions. SUBJECTS AND METHODS: Five hundred and eighty-two consecutive patients with thoracic lesions who underwent same-session sequential CT-guided FNA and CNB procedures were studied. The final diagnosis, which was achieved by either agreement of percutaneous procedures with clinical follow-up, bronchoscopy or thoracotomy was available for all cases. The diagnostic yield of the combined FNA+CNB procedures was compared with that of each alone. RESULTS: Adequate samples were obtained in 541 (93%) of FNAs and 513 (88%) of CNBs. Of 582 lesions, 419 (72%) were malignant and 163 (28%) were benign. For malignant lesions, the sensitivity, specificity and accuracy of the procedures were: 376/419 (89.7%), 136/163 (83.4%), and 88% for FNA; 317/419 (75.6%), 138/163 (84.7%), and 78% for CNB; 400/419 (95.5%), 154/163 (94.5%), and 95% for FNA+CNB. The sequential procedures showed significantly better sensitivity, specificity and accuracy compared with either FNA or CNB separately (p<0.003). For the 163 benign lesions, 76 (47%) had a specific benign pathological diagnosis. The diagnosis was obtained in 16/76 (21%) by FNA, in 54/76 (71%) by CNB, and in 60/76 (79%) by FNA+CNB. There was no significant difference between the results of the sequential procedures and CNB alone (p>0.05). CONCLUSIONS: Sequential FNA and CNB improve the diagnostic accuracy of percutaneous CT-guided procedures in malignant lesions. There was only mild improvement, which was not statistically significant, for the diagnosis of benign specific lesions by the sequential procedures compared with the yield of CNB alone.

Transthoracic needle biopsy of lung masses: a survey of techniques.

AIM: In order to assess the range and everyday use of the various techniques for percutaneous transthoracic needle biopsy of lung masses in the USA and Canada, we surveyed thoracic radiologists in academic and community practice on their standard approach to the procedure. MATERIALS AND METHODS: The 300 questionnaires that were mailed to members of the Society of Thoracic Radiology throughout the USA and Canada contained specific questions on their approach to a transthoracic needle biopsy of a routine case of a 3cm lung mass located in the right lower lobe 1cm from the pleural surface. RESULTS: A total of 140 (47%) members responded. Of the 139 responders who performed lung biopsies, 103 (74%) were located at a teaching centre affiliated to a university or medical school, and 36 (26%) were community-based radiologists. In total 97 (70%) replied that they would perform the procedure under CT guidance, 31 (22%) under either CT or fluoroscopy guidance, and 11 (8%) only under fluoroscopy. Fine-needle aspiration was the procedure of choice for the given case by 101 (73%) responders, whereas 20 (14%) preferred doing core biopsy, and 18 (13%) chose both techniques. On-site cytology confirmation for obtaining diagnostic material was available to 101 (73%) responders. Before performing the procedure, 107 (77%) verified coagulation tests whereas 32 (23%) did not. Follow-up imaging for pneumothorax assessment was not routinely performed by 15 (11%) responders. CONCLUSION: The majority of radiologists performed percutaneous transthoracic needle biopsy of a lung mass under CT guidance, by fine-needle aspiration, using repeated pleural puncture technique, and with a cytologist on site. A significant minority did not obtain coagulation screening before the procedure, and a small minority did not routinely assess for pneumothorax by late chest radiography.

Molecular structure of the bony tissue after experimental trauma to the mandibular region followed by laser therapy.

OBJECTIVE: We investigated the therapeutic efficiency of laser irradiation and Bio-Oss, both and separately, on the post-traumatic regeneration of bone tissue in rats using infrared spectroscopy as an informative and accurate measuring method. BACKGROUND DATA: The therapeutic effect of low-power laser irradiation on bone tissue regeneration processes in animal models has been studied using morphogenic, biochemical, roentgenographic and electron microscopic measurements. Natural bone minerals, such as Bio-Oss collagen, were recommended for the reconstruction of bone defects in the alveolar process. MATERIALS AND METHODS: 29 male Wistar rats, divided into four random groups in a blinded manner were operated on the right alveolar process. A bone defect was made by penetrating the right alveolar process of the mandible bone using a 3-mm drill. The rats were divided into four groups as follows: Group I, left side served as intact bone and right injured side as the control; Group II, right injured side was treated by organic bovine bone (Bio-Oss); Group III, right side bone defect was treated by HeNe laser (632.8 nm, 35 mW) applied transcutaneously for 20 min to the injured area daily for the following 14 consecutive days; and Group IV, Bio-Oss was placed loosely in the right side defect followed by laser treatment. After 2 weeks, the intact bone and bone replicas of the trauma area were removed and analyzed by infra-red spectroscopy technique. The composition and the structure of the bone tissue mineral substances were determined and compared among the four groups. For quantitative analysis of the regenerative bone process, the Mineralization index was used. An increase in this index indicates regenerative bone processes. RESULTS: The normal state analysis of the IR spectra of the normal alveolar bone tissue within the intervals of 400 to 4000 cm(-1) revealed characteristic absorption bands for the inorganic bone component in spectrum regions 450-1480 cm(-1), and the organic component at 1540-3340 cm(-1). In the case of trauma, the intensity of absorption of the inorganic component was decreased by 54%, and the absorption band became narrow, which can be interpreted as quantitative changes of the bone tissue mineral content. The wavelength characteristics of the inorganic component remained unchanged; that is, the induced trauma under these experimental conditions did not provoke alterations in the structure of the phosphate framework. The organic component showed decreased absorption by 10-15%, compared to the normal bone, and slight displacement of the wavelength, which can be interpreted as changes occurring in the quality of the organic content of the bone tissue. In the Bio-Oss-treated group, the intensity of absorption of the inorganic component increased by 43%, compared to the control injured area; however, there was a decrease of 22.6% in the normal bone. The wavelength characteristics of the inorganic component remained unchanged. The organic component showed similar absorption results in the injured non-treated group and absorption was 10-15% less than in the normal bone. Mineralization Index in the Bio-Oss-treated group was 0.93, compared to 0.63 in the control group and 2.04 in the normal bone. In the laser-treated group, the intensity of absorption of the inorganic component increased by 62, compared to the control injured area, and decreased only 11.4% in the normal bone. The wavelength characteristics of the organic component remained unchanged; that is, the organic component was similar to that of normal bone. Mineralization Index in the laser-treated group increased significantly to 1.86, compared to 0.63 in the control group and 2.04 in the normal bone. In the combined laser and Bio-Oss-treated groups, the intensity of absorption of the inorganic component and organic component was similar to that of normal bone. Mineralization Index in this group increased significantly to 1.98, compared to 0.63 in the control group and 2.04 in the normal bone. CONCLUSION: The results suggest that low-power laser irradiatults suggest that low-power laser irradiation alone and in combination with Bio-Oss enhances bone healing and increases bone repair.

Omental infarction: an unusual cause of acute abdomen in children.

Acute abdomen is caused by a wide variety of etiologies, many of which require surgical intervention. Two boys were hospitalized for acute abdominal pain and low-grade fever. Physical examination revealed epigastric and right upper abdominal fullness, and laboratory studies showed elevated erythrocyte sedimentation rates, with normal leukocyte counts and coagulation profiles. Abdominal ultrasound and computerized tomography revealed pseudotumor in both cases. Symptomatic treatment and cefazolin were administered, and pain and fever subsided after 6 to 10 days. Pseudotumor due to omental infarction can present as acute abdomen in children. A high index of suspicion and the use of both ultrasonography and computerized tomography will help avoid unnecessary surgical intervention in such cases.

High b value q-space-analyzed diffusion MRI in vascular dementia: a preliminary study.

High b value diffusion weighted magnetic resonance imaging (high-b DWI) was used to characterize white matter changes in the brain of patients with vascular dementia (VaD). Hyperintense white matter areas detected by T2-weighted magnetic resonance imaging (MRI) represent lesions, also termed leukoaraiosis that are very common in VaD as well as in other types of dementia. Therefore, the role of white matter changes in the cognitive and memory decline that occurs in VaD patients is still under debate. High-b DWI, analyzed using the q-space approach, is a more sensitive MRI method for detection of white matter changes. High-b DWI revealed massive white matter loss in VaD patients that surpassed the boundaries of T2 hyperintensities. This technique, therefore, might serve as a better indication for the extensive nerve fiber loss in the white matter that is caused by vascular disease.

High b-value q-space analyzed diffusion-weighted MRI: application to multiple sclerosis.

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) which affects nearly one million people worldwide, leading to a progressive decline of motor and sensory functions, and permanent disability. High b-value diffusion-weighted MR images (b of up to 14000 s/mm(2)) were acquired from the brains of controls and MS patients. These diffusion MR images, in which signal decay is not monoexponential, were analyzed using the q-space approach that emphasizes the diffusion characteristics of the slow-diffusing component. From this analysis, displacement and probability maps were constructed. The computed q-space analyzed MR images that were compared with conventional T(1), T(2) (fluid attenuated inversion recovery (FLAIR)), and diffusion tensor imaging (DTI) images were found to be sensitive to the pathophysiological state of white matter. The indices used to construct this q-space analyzed MR maps, provided a pronounced differentiation between normal tissue and tissues classified as MS plaques by the FLAIR images. More importantly, a pronounced differentiation was also observed between tissues classified by the FLAIR MR images as normal-appearing white matter (NAWM) in the MS brains, which are known to be abnormal, and the respective control tissues. The potential diagnostic capacity of high b-value diffusion q-space analyzed MR images is discussed, and experimental data that explains the consequences of using the q-space approach once the short pulse gradient approximation is violated are presented.

Feeling or features: different sensitivity to emotion in high-order visual cortex and amygdala.

Emotionally loaded visual stimuli have shown increased activation in visual and cortex limbic areas. However, differences in visual features of such images could confound these findings. In order to manipulate valence of stimuli while keeping visual features largely unchanged, we took advantage of an "expressional transfiguration" (ET) effect of faces. In addition, we used repetition effects, which enabled us to test more incisively the impact of the ET effect. Using the ET manipulation, we have shown that the activation in lateral occipital complex (LOC) was unaffected by valence attributes, but produced significant modulation of fMR adaptation. Contrary to LOC, amygdala activation was increased by ET manipulation unrelated to the adaptation. A correlation between amygdala and LOC adaptation points to a possible modulatory role of the amygdala upon visual cortex short-term plasticity.

Renal multigated spectral Doppler imaging before and after captopril challenge.

RATIONALE AND OBJECTIVES: A new method of measurement, simultaneous multigated spectral Doppler imaging (MSDI), was used to quantify the hemodynamic changes in kidneys after administration of captopril. METHODS: Forty kidneys in 22 hypertensive patients were included in the study. All underwent MSDI and scintigraphy before and after administration of captopril. RESULTS: With scintigraphy used as the gold standard for diagnosing renal artery stenosis (RAS), three kidneys were found to be positive for RAS. Multigated spectral Doppler imaging detected a decrease in the resistive index after administration of captopril in all patients with RAS and correctly excluded RAS in one patient who was diagnosed as having RAS on scintigraphy. The resistive index was increased after captopril administration in normally functioning kidneys and was unchanged in kidneys with impaired function. CONCLUSIONS: With further supportive evidence, MSDI may prove to be a powerful tool for the acquisition of resistive index information and may increase the value of the resistive index as a physiological hemodynamic parameter in the evaluation of normal and abnormal conditions.

Non-neoplastic intratesticular lesions mimicking tumour on ultrasound.

It has recently been emphasized that the incidence of benign testicular lesions is much higher than previously suspected. Sonography is reported to have a high sensitivity but poor specificity in the evaluation of intratesticular abnormalities. This report reviews the common and unusual lesions that can mimic testicular tumour on ultrasound, and discusses the clinical and sonographic features that may help to narrow the differential diagnosis and guide management.

Varicocele and the testicular-renal venous route: hemodynamic Doppler sonographic investigation.

The aim of this study was to quantify the anatomic and hemodynamic components of the testicular venous drainage for the purpose of understanding their mechanisms of interacting in producing mutual effects, such as "nutcracker" phenomenon, reflux, and varicoceles. Seventy-five male subjects were studied at rest and during Valsalva maneuver. Aortomesenteric distance and angle, flow velocity in different segments of the renal veins, testicular vein diameter, and flow inversion were evaluated using standard ultrasound equipment with spectral and color Doppler capabilities. The velocity of flow in the proximal segment of the left renal vein (17.5 cm/s) was found to be significantly lower than that in both the distal left renal vein (121 cm/s) and the right renal vein (37 cm/s). The flow velocity in the proximal left renal vein decreased with decrease in the aortomesenteric distance and angle. Testicular vein diameters greater than 3 mm were statistically associated with decreased superior mesenteric artery angle. A significant association also was found between the left testicular vein diameter (in Valsalva maneuver) and inversion of flow. The decrease in flow velocity in the left renal vein proximal to the bifurcation of the superior mesenteric artery from the aorta supports the "nutcracker" theory. An association was found between the decrease of superior mesenteric artery angle and the increase in testicular vein diameter. Another association exists between the presence of reflux during Valsalva maneuver and increased testicular vein diameter. These finding were significant only for testicular vein diameter values greater than 3 mm.

Quantitative estimation of attenuation in ultrasound video images: correlation with histology in diffuse liver disease.

RATIONALE AND OBJECTIVES: To determine the relationship between the attenuation of backscatter intensity in B-scan images of the liver and diffuse liver disease in order to assess the usefulness of this method in providing quantitative objective characterization of diffuse liver diseases in general and in fatty liver in particular. METHODS: Twenty-four healthy volunteers and 28 patients with elevated liver enzyme levels who underwent liver biopsy were included in this study. An automatic far-field slope (FFS) algorithm that estimates the decrease in amplitude of the backscattered echo as a function of beam depth was implemented on the noncompensated image that was acquired on a commercial phased-array ultrasound system fitted to a custom-built interface card. The images were processed at a work-station. All scans were acquired repeatedly, read, and graded blindly by experienced ultrasound radiologists. Histology obtained via needle biopsy was reviewed without knowledge of the ultrasound findings. RESULTS: Analysis of the FFS data for fatty infiltration in all patient groups yielded a sensitivity of 67%, a specificity of 77%, a positive predictive value (PPV) of 77%, negative predictive value (NPV) of 67%, and an accuracy of 71%. The mean score of the ultrasound reviewers showed a sensitivity of 82%, a specificity of 66%, a PPV% of 68%, an NPV of 81%, and an accuracy of 72%. Normal FFS values (false-negative) were found in five patients with proved fatty infiltration. All of these patients had coexistent moderate to severe hepatic inflammation. However, FFS data in patients with uncomplicated (pure) fatty infiltration revealed a sensitivity of 100%, a specificity of 80%, a PPV of 89%, an NPV of 100%, and an accuracy of 92%. The best ultrasound score yielded a sensitivity of 100%, a specificity of 60%, a PPV of 80%, an NPV of 100%, and an accuracy of 85% in the same patients. CONCLUSIONS: The data demonstrate an excellent sensitivity (100%) of the FFS values in patients with uncomplicated fatty infiltration. This was also the only group of patients in whom the FFS score was superior to the radiologists' best score. The FFS method can be used as a tool to follow up the response to a clinical or research treatment and to obtain standardization of pattern interpretation independently of the individual reader.

The septic versus nonseptic inflamed joint: MRI characteristics.

OBJECTIVE: To differentiate the MR features of septic versus nonseptic inflamed joints. DESIGN AND PATIENTS: Thirty patients were referred for MRI with inflamed joints (19 were subsequently found to be septic and 11 nonseptic). At 1.5 T enhanced MRI five groups of signs related to joint space, synovium, cartilage, bone and peri-articular soft tissue respectively were assessed and compared between the septic and nonseptic groups. RESULTS: The prevalence of MRI findings in septic versus nonseptic joints (respectively) was as follows: effusion (79% vs 82%), fluid outpouching (79% vs 73%), fluid heterogeneity (21% vs 27%), synovial thickening (68% vs 55%), synovial periedema (63% vs 55%), synovial enhancement (94% vs 88%), cartilage loss (53% vs 30%), bone erosions (79% vs 38%), bone erosions enhancement (77% vs 43%), bone marrow edema (74% vs 38%), bone marrow enhancement (67% vs 50%), soft tissue edema (63% vs 78%), soft tissue enhancement (67% vs 71%), periosteal edema (11% vs. 10%). The presence of bone erosions appeared to be an indicator for an infected joint (P=0.072); coexistence of bone marrow edema slightly improves the significance (0.068). A similar trend was obtained when combining bone erosions with either synovial thickening, synovial periedema, bone marrow enhancement or soft tissue edema (P=0.075). CONCLUSIONS: The combination of bone erosions with marrow edema is highly suggestive for a septic articulation; the additional coexistence of synovial thickening, synovial edema, soft tissue edema or bone marrow enhancement increases the above level of confidence. Similar to conventional radiography, the single sign that appeared to show a significant trend was the presence of bone erosions. However, no single sign or combination could either be considered pathognomonic or exclude the presence of a joint infection.

The role of ultrasound in the diagnosis of stitch granulomas following paediatric herniotomy.

OBJECTIVE: To study the role of US in the diagnosis of stitch granulomas following paediatric herniotomy. MATERIALS AND METHODS: A retrospective 10-year study of herniotomies performed by a paediatric surgical service. RESULTS: Twenty children developed stitch granulomas following herniotomy. In all cases, silk sutures had been used in the repair. Masses appeared 1-10 years following surgery and were demonstrated by preoperative US in 17 patients, by CT alone in 1 patient and by both CT and US in 2 patients. CONCLUSIONS: US is an accurate and cost-effective method for evaluating stitch granulomas following herniotomy in children. The procedure is also valuable in marking the position of these foreign bodies prior to removal.

Synovial effusion in reflex sympathetic dystrophy: an additional sign for diagnosis and staging.

PURPOSE: To improve the present MRI criteria for diagnosis and staging of reflex sympathetic dystrophy (RSD) by including increased joint fluid as an additional MRI sign of RSD. DESIGN AND PATIENTS: One hundred and fourteen extremities (69 affected and 45 contralateral controls) in 57 consecutive patients with RSD were evaluated using a 1.5-T unit. T1- and T2-weighted pulse sequences, often with fat suppression, were used before and after administration of intravenous contrast enhancement (Gd). Following T2-weighted image digitization the volume of synovial fluid was measured with a computer model. RESULTS: Effusions were detected in 61% of the extremities suspected of RSD and in 44% of the contralateral control joints. The mean fluid quantity measured in the symptomatic articulation was 201 mm3. MRI diagnosis of RSD based on previously described criteria was done in 62% of the patients, yielding a sensitivity of 60%. Effusions were present in 79% of the false negative MRI cases. Retrospectively considering the presence of fluid as a potential positive criterion for RSD increases the sensitivity by 31% (to 91%). CONCLUSIONS: Joint effusions are probably associated with early stages of RSD. Adding effusion to the list of radiological criteria for RSD increases the sensitivity of MRI from 60% to 91%.