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.

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.

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.

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.

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.

MR imaging of histiocytosis X in the central nervous system.

The magnetic resonance imaging features of two cases of histiocytosis X in the hypothalamus and one in the cerebral hemispheres are described. The lesions were best seen with spin-echo technique using a long repetition time (TR = 1580 msec) and long echo time (TE = 80 msec). Sagittal images provided the best anatomicotopographic evaluation of the lesions. Comparison with computed tomography with and without contrast enhancement showed an advantage with magnetic resonance imaging.

Contrast-enhanced MR imaging of malignant brain tumors.

Magnetic resonance (MR) imaging was performed before and serially after intravenous injection of 1 mmol/kg gadolinium-DTPA (Schering) in 17 patients with clinical and histologic diagnosis of malignant cerebral tumors. There was a decrease of 1% in T1 and 10% in T2 in normal white matter and a decrease of 8% in T1 and 14% in T2 in normal gray matter. Contrast enhancement was observed in 16 of the 17 tumors. In the region of maximal enhancement a mean decrease of 16% in T1 was observed in low-grade gliomas, a mean decrease in T1 of 29% was seen in high-malignancy gliomas, and a mean decrease in T1 of 33% was observed in metastases. The decreases in T1 persisted for at least 50 min. In one case the central cystic region of the tumor displayed a decrease in T1 and T2. Measurements of signal intensity displayed maximal contrast enhancement with an IR 1500/500/44 sequence, much less with SE 1500/44, and least with SE 1500/80. Edema was observed on precontrast images in 14 cases, but satisfactory definition of the tumor-edema margin was only possible in four cases. After contrast enhancement this margin was defined in 10 cases. In four of the 17 cases areas of apparent "edema" seen before administration of Gd-DTPA displayed significant contrast enhancement and probably represented tumor infiltration. Comparison with CT showed a greater degree of contrast enhancement on MR images in eight cases, an equal degree in eight cases, and greater enhancement on CT in one case.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Contrast-enhanced magnetic resonance imaging of tumours of the central nervous system: a clinical review.

The clinical application of the intravascular paramagnetic contrast agent gadolinium-DTPA for magnetic resonance imaging (MRI) imaging of tumours of the central nervous system (CNS) has been assessed over the past 3 years. Various patterns of contrast enhancement were observed, and situations in MRI where the administration of contrast medium may be useful have been defined. These include lesions which are isointense with normal brain matter, the separation of tumour from surrounding oedema, evaluation of the degree of blood-brain barrier breakdown, delineation of tumours obscured by overlying calcification on computed tomography (CT) and in the investigation of lesions in anatomical areas where CT has known limitations (brain stem, cervical spine). Changes in relaxation times in normal and abnormal tissues following contrast medium, toxicity and dosage of gadolinium-DTPA, and MRI pulse sequence techniques are reviewed.

Parathyroid sonography: diagnostic accuracy related to shape, location, and texture of the gland.

The sonographic features of 51 pathological parathyroid glands detected pre-operatively were analysed. Atypical texture was found in 23.5% and variation in shape in 15.6% of the cases. Cystic parathyroid glands are difficult to differentiate from thyroid cysts, and may be the cause of false positive diagnosis, as in three cases in this series. Topographic assessment showed a relatively low sensitivity in detecting disease in the right upper gland (50%) and in the upper mediastinum (70%). The decreased accuracy in these regions is probably because of the particular anatomical location of the right upper gland and sonographic limitations in screening the mediastinal region. Awareness by the radiologist and surgeon of the variations in texture and location may influence both diagnosis and intraoperative detection of the abnormal parathyroid gland.

Parathyroid localization. Sonographic-surgical correlation.

Sonographic localization of enlarged parathyroid gland was performed in 37 patients suspected of hyperparathyroidism who underwent surgical exploration of the neck. Nine of those patients were clinically asymptomatic. Most of the others presented with urolithiasis. The sonograms were obtained by conventional and high resolution realtime (10 mHz). Of the 37 patients, 31 patients had a single adenoma, three patients had two adenomas, and two patients had hyperplasia. Analysis of the results has shown accuracy of 84 per cent. The sensitivity of the procedure was 79.5 per cent and the specificity was 98 per cent. The exact side and location of the enlarged parathyroid in relation to the thyroid gland was predicted in 91 per cent. The false-negative cases were due to abnormal location (gland in mediastinum or incorporated within the thyroid). The false-positive findings were all colloid cysts located at the periphery of the thyroid parenchyma. Preoperative confirmation and localization of enlarged parathyroid glands facilitated the decision for surgical intervention, especially in hypercalcemic asymptomatic patients and in high operative risk patients. The duration of operation and postoperative complications were significantly reduced.

Delayed diagnosis of a primary psoas abscess mimicking septic arthritis of the hip.

A 5-year-old boy presented with a limp, fever, and right hip pain of 72 hours' duration. An intensive workup of right hip pain synovitis failed to diagnose any local pathology. Delayed diagnosis of psoas abscess was made on the 12th day of hospitalization. A rapid recovery with no further complications followed surgical evacuation of the abscess.

The Treatment of Soft Tissue Hemorrhages in a Severe Classical Hemophiliac with an Unusual Antibody to Factor VIII.

A known severe classical hemophiliac patient presented with a large hemorrhage into his left shin and complained of paresthesia in his toes. Large doses of factor VIII had failed to halt the expanding shin hematoma. Laboratory investigations revealed an antibody titer of 5 Bethesda units. In vitro and in vivo testing showed swift neutralization of factor VIII to a level of 20% and thereafter degradation of factor VIII in accordance to the half-life expectancy. The patient was successfully treated with a continuous infusion of small doses of cryoprecipitate. The Bethesda method of antibody measurement does not distinguish between low and high affinity antibodies and thus in vitro testing should be carried out before a decision is made on the use of expensive activated prothrombin complex. The initial approach of the physical therapist is to aid in attempting to limit the swelling and enhance hematoma reabsorption. Once the bleeding has been controlled, a long-term physical therapy program is necessary to regain dorsiflexion of the ankle joint.J Orthop Sports Phys Ther 1988;10(4):138-141.

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.

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.

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.