Left Main Coronary Artery Thrombosis With Acute Myocardial Infarction: A Management Dilemma

Left main coronary artery (LMCA) thrombosis with acute myocardial infarction is a rare condition with very high mortality. The low incidence of this condition and exclusion of patients with LMCA thrombosis from clinical trials prevent the development of optimal management strategy in these patients. Therefore, there are no clear-cut guidelines describing an evidence-based approach for this condition. We describe a patient with LMCA thrombosis presenting with acute myocardial infarction, who was found to have hypercoagulable state related to homocysteinemia on further work-up. This case highlights the challenges faced during the management of this rare condition due to lack of clear-cut guidelines describing an evidence-based approach.     

A Comparison Study of Vector Velocity,Spectral Doppler and Magnetic Resonance of Blood Flow in the Common Carotid Artery

Magnetic resonance phase contrast angiography (MRA) is the gold standard for blood flow evaluation. Spectral Doppler ultrasound (SDU) is the first clinical choice, although the method is angle dependent. Vector flow imaging (VFI) is an angle-independent ultrasound method. The aim of the study was to compare VFI- and SDU-estimated peak systolic velocities (PSV) of the common carotid artery (CCA) with PSV obtained by MRA. Furthermore, intra- and inter-observer agreement was determined. MRA estimates were significantly different from SDU estimates (left CCA: p?<?0.001, right CCA: p?<?0.001), but not from VFI estimates (left CCA: p?=?0.28, right CCA: p?=?0.18). VFI measured lower PSV in both CCAs compared with SDU (p?<?0.001) with improved precision (VFI: left: 24%, right: 18%; SDU: left 38%, right: 23%). Intra- and inter-observer agreement was almost perfect for VFI and SDU (inter-observer correlation coefficient: VFI 0.88, SDU 0.91; intra-observer correlation coefficient: VFI 0.96, SDU 0.97). VFI is more accurate than SDU in evaluating PSV compared with MRA.     

NEED FOR FACIAL REANIMATION AFTER OPERATIONS FOR VESTIBULAR SCHWANNOMA: PATIENTS PERSPECTIVE

A total of 779 patients operated on for vestibular schwannoma mostly by the translabyrinthine approach in Denmark during the period 1976-2000 answered a questionnaire about various postoperative consequences. In this paper we describe the patients' facial function evaluated by professionals one year postoperatively and self-evaluated by each patient according to the House-Brackmann scale at the time of the questionnaire. The patients' self-evaluation was more pessimistic than that of the professionals with 26% reporting House-Brackmann grade IV-VI, compared with 20%. One hundred and seventeen (15%) of 779 patients considered their facial palsy to be a big problem and 125 patients (16%) were interested in surgical treatment for the sequelae of facial palsy. Seventy-eight (10%) had already had some kind of operation, usually the VII-XII coaptation. Thirty-three of 61 patients who had already been operated on for facial palsy were interested in further surgical treatment. One hundred and ninety-five patients (25%) had some kind of operation on the eye, mostly (88%) a tarsorrhaphy. Reanimation procedures such as a palpebral gold weight or a spring, apparently still have a small place in Denmark. In conclusion, there seem to be a considerable and unmet need for surgical reanimation of facial function in patients with facial palsy after operations for vestibular schwannoma in Denmark.     

Proteasome inhibition leads to early loss of synaptic proteins in neuronal culture

A dysfunctional ubiquitin proteasome system may be a mediating factor of disease progression in Lewy body dementia (LBD). The effects of proteasome inhibition using lactacystin and epoxomicin in primary neuronal culture were studied to assess the validity of this model to reflect the cortical pathology of LBD. Treatment of primary cortical neurons with 5???M lactacystin for 24?h led to a 38?% reduction in the levels of ??-III-tubulin (p?<?0.05), a 48?% reduction in the levels of synaptophysin (p?<?0.05) and a 74?% reduction in the levels of drebrin (p?<?0.01), when compared to controls. Results for epoxomicin were similar. The loss of neuronal protein occurred prior to any loss of mitochondrial activity or cell death. The results are reflective of the loss of synapses and the synaptic changes observed in LBD, which may be an early event in the neurodegeneration of LBD. The similarities with the pathological changes in LBD highlight the possibility that this model can potentially provide a platform to test novel treatments.     

Common Carotid Artery Flow Measured by 3-D Ultrasonic Vector Flow Imaging and Validated with Magnetic Resonance Imaging

Ultrasound (US) examination of the common carotid artery was compared with a through-plane magnetic resonance imaging (MRI) sequence to validate a recently proposed technique for 3-D US vector flow imaging. Data from the first volunteer examined were used as the training set, before volume flow and peak velocities were calculated for the remaining eight volunteers. Peak systolic velocities (PSVs) and volume flow obtained with 3-D US were, on average, 34% higher and 24% lower than those obtained with MRI, respectively. A high correlation was observed for PSV (r = 0.79), whereas a lower correlation was observed for volume flow (r = 0.43). The overall standard deviations were ±5.7% and ±5.7% for volume flow and PSV with 3-D US, compared with ±2.7% and ±3.2% for MRI. Finally, the data were re-processed with a change in the parameter settings for the echo-canceling filter to investigate its influence on overall performance. PSV was less affected by the re-processing, whereas the difference in volume flow between 3-D vector flow imaging and MRI was reduced to ?9%, and with an improved overall standard deviation of ±4.7%. The results illustrate the feasibility of using 3-D US for precise and angle-independent volume flow and PSV estimation in vivo.