Is Carotid Plaque Contrast Enhancement on MRI Predictive for Cerebral or Cardiovascular Events? A Prospective Cohort Study.

OBJECTIVE: The aim of this study was to correlate carotid plaque contrast enhancement (CPCE) to onset of cerebral/cardiovascular events (CCVE) in patients with atherosclerotic carotid disease. METHODS: The ethics committee approved this prospective study. Patients with carotid artery stenosis underwent magnetic resonance angiography before/after injection of 0.1 mmol/kg of gadobenate dimeglumine. Carotid plaque contrast enhancement was graded as follows: 0, no CPCE; 1, 1 single enhancement focus; 2, 2 or more foci. RESULTS: Seventy-seven patients (71 ± 9 years) had a stenosis degree: 34 mild, 16 moderate, 27 severe at the right side, and 36, 15, and 25 at the left side. Carotid plaque contrast enhancement was 0 in 30 patients, 1 in 26, 2 in 11 at the right, and 37, 19, and 13 at the left. Forty-seven CCVE occurred after magnetic resonance imaging, correlated to both stenosis degree (P = 0.006) and CPCE (P = 0.032). Excluding surgery/stenting, the correlation held only for CPCE (P = 0.017). Of 49 patients showing CPCE, 5 (10%) reported CCVE; of 21 patients without CPCE, none reported CCVE (P = 0.129). CONCLUSIONS: The absence of CPCE seems to be a negative predictor for CCVE.

Evaluation of inflammatory status of atherosclerotic carotid plaque before thromboendarterectomy using delayed contrast-enhanced subtracted images after magnetic resonance angiography.

OBJECTIVE: To investigate the correlation among carotid plaque contrast enhancement (CPCE) at MRI, inflammatory cell infiltration (ICI) at histopathology, and carotid stenosis degree. MATERIALS AND METHODS: Twenty-eight patients (19 males; mean age 67±9 years) scheduled for thromboendarterectomy prospectively underwent 1.5-T MR imaging using: (a) axial T1-weighted gradient-echo (T1wGRE) sequence centered on carotid bifurcations; (b) contrast-enhanced MR angiography (CE-MRA) with 0.1 mmol/kg of gadobenate dimeglumine; (c) enhanced axial T1wGRE sequence as in (a), 3 min after contrast injection. A three-point score system (absent, focal, wide) was used to assess CPCE on native and subtracted MRI images (c minus a) and ICI at histopathology. Carotid stenosis degree was determined on CE-MRA. RESULTS: Six CPCE studies were discarded due to patient movement. In the remaining 22 studies, CPCE was absent, focal and wide in 13, 6 and 3 cases, respectively; ICI was absent, focal and wide in 13, 7 and 2 cases, respectively (k=0.57). On CE-MRA 21/28 stenoses were severe and 7/28 moderate. There was no correlation either with ICI (p=1.000, n=28) or CPCE (p=0.747, n=22). CONCLUSION: The correlation between CPCE and ICI suggests a role for CPCE as an independent marker of plaque inflammation.

Evaluation of carotid vessel wall enhancement with image subtraction after gadobenate dimeglumine-enhanced MR angiography.

OBJECTIVES: This study was aimed at testing the value of image subtraction for evaluating carotid vessel wall enhancement in contrast-enhanced MR angiography (MRA). MATERIALS AND METHODS: IRB approval was obtained. The scans of 81 consecutive patients who underwent carotid MRA with 0.1 mmol/kg of gadobenate dimeglumine were reviewed. Axial carotid 3D T1-weighted fast low-angle shot sequence before and 3 min after contrast injection were acquired and subtracted (enhanced minus unenhanced). Vessel wall enhancement was assigned a four-point score using native or subtracted images from 0 (no enhancement) to 3 (strong enhancement). Stenosis degree was graded according to NASCET. RESULTS: With native images, vessel wall enhancement was detected in 20/81 patients (25%) and in 20/161 carotids (12%), and scored 2.0+/-0.6 (mean+/-standard deviation); with subtracted images, in 21/81 (26%) and 22/161 (14%), and scored 2.5+/-0.6, respectively (P<0.001, Sign test). The overall stenosis degree distribution was: mild, 41/161 (25%); moderate, 77/161 (48%); severe, 43/161 (27%). Carotids with moderate stenosis showed vessel wall enhancement with a frequency (17/77, 22%) significantly higher than that observed in carotids with mild stenosis (1/41, 2%) (P=0.005, Fisher exact test) and higher, even though with borderline significance (P=0.078, Fisher exact test), than that observed in carotids with severe stenosis (4/43, 9%). CONCLUSION: Roughly a quarter of patients undergoing carotid MRA showed vessel wall enhancement. Image subtraction improved vessel wall enhancement conspicuity. Vessel wall enhancement seems to be an event relatively independent from the degree of stenosis. Further studies are warranted to define the relation between vessel wall enhancement and histopathology, inflammatory status, and instability.

Progressive knowledge loss: a longitudinal case study.

The evolution of the progressive loss of semantic knowledge of a patient, VZ, with lesions mainly affecting the infero-medial temporal lobes, was followed for two years. At the beginning of the study VZ's performance was mainly characterized by a category-specific deficit for living things and a modality-specific deficit for perceptual attribute knowledge. As time went on, VZ's disorder affected all categories by changing the relationship between category and attribute knowledge. Data show that dissociations may change in the course of progressive cognitive breakdown, depending on both degeneration stage and task demands. VZ's performance is discussed in the light of the most influential theoretical accounts. Methodological suggestions regarding longitudinal studies of degenerative patients are also put forward.

Intraforaminal O(2)-O(3) versus periradicular steroidal infiltrations in lower back pain: randomized controlled study.

BACKGROUND AND PURPOSE: Reports about steroids and oxygen-ozone therapy to treat lower back pain have been increasing. The purpose of our study was to compare the clinical outcomes in patients treated with infiltrations of O(2)-O(3) gas or steroids at short-, medium-, and long-term follow-up. METHODS: A total of 306 patients (166 with primarily disk disease, 140 with nondisk vertebral disease) with acute or chronic low back and sciatic nerve pain received a CT-guided intraforaminal infiltration of an O(2)-O(3) gas mixture or an periradicular infiltration of steroids. Neurologists unaware of the type of treatment assessed the patients. RESULTS: At 1-week follow-up, most patients had a complete remission of pain, regardless of the treatment. At 6-month follow-up, differences in favor of O(2)-O(3) treatment were significant in patients with disk disease (P = .0021) but not in those without disk disease (P = .0992). Clinical outcomes were poor in 13 (15.1%) of 86 patients receiving O(2)-O(3) infiltration and in 18 (22.5%) of 80 patients receiving steroid injection (P = .2226). Among patients without disk disease, six (8.6%) of 70 patients receiving O(2)-O(3) infiltration but 21.4% of the patients receiving steroid injections had poor outcomes (P = .0332). CONCLUSION: Oxygen-ozone treatment was highly effective in relieving acute and chronic lower back pain and sciatica. The gas mixture can be administered as a first treatment to replace epidural steroids.