Noninvasive evaluation of knee meniscal tears: preliminary comparison of MR imaging and CT

One hundred twenty knees were examined prospectively with both axial computed tomography (CT) and magnetic resonance (MR) imaging to compare the value of these techniques in patients with clinical evidence of meniscal tears. Sixty-four of these knees were subsequently evaluated with diagnostic arthroscopy. In this group, CT was superior to MR imaging for meniscus evaluation in 29.7% of the knees, equal to MR in 54.7%, and inferior to MR in 15.6%. Although surface-coil MR imaging shows great promise and has numerous advantages over more conventional techniques, this preliminary experience suggests that, at least with certain imaging equipment and techniques, CT may be slightly more efficacious than 0.5-T MR imaging in meniscus evaluation. However, further comparative studies at higher field strengths are needed before the relative roles of CT and MR imaging can be established.     

In vitro regulation of immunoglobulin synthesis after marrow transplantation. I. T-cell and B-cell deficiencies in patients with and without chronic graft-versus-host disease

Twenty-four patients with aplastic anemia or acute leukemia were treated by marrow grafts from HLA-identical donors after conditioning with high doses of cyclophosphamide and/or today body irradiation. They were studied between 4 and 63 mo (median 14.2) after transplantation. Seventeen patients had chronic graft-versus-host disease (C-GVHD) and 7 were healthy. They were studied for defects in their T- and B-cell function using and indirect hemolytic plaque assay for Ig production after 6 days of culture in the presence of pokeweek mitogen. T or B cells from the patients with or without C-GVHD were cocultured with T or B cells from their HLA-identical marrow donors or unrelated normal controls. Intrinsic B-cell defects, lack of helper T-cell activity, and suppressor T-cell activity were more frequently found in patients with C-GVHD than in healthy patients. Fifteen of the 17 patients with C-GVHD showed on or more defects in their T-and B-cell function compared to only 3 of the 7 patients without C-GVHD. None of the healthy controls, including the marrow donors, showed defects in their T- and B-cell functions. These in vitro findings may be helpful in assessing the process of immune reconstitution and the immunologic aberration found after human marrow transplantation.     

Comparison of vasa vasorum after intravascular stent placement with sirolimis drug‐eluting and bare metal stents

The cytostatic drug, sirolimis has shown prevention in neointimal hyperplasia after stent placement. Recent studies have shown persistent inflammation seen with drug‐eluting stents (DES) may result in late stent thrombosis. The aim of this study is to compare effects of bare metal stents (BMS) and sirolimis DES on the neointima and vasa vasorum in stented rabbit aortas. Stents were implanted in eight New Zealand rabbits for 9 weeks. Group I rabbits received BMS. Group II rabbits received sirolimis DES. A balloon‐mounted BMS or DES was placed in the infrarenal aorta. Following euthanasia, aortas were perfused with barium sulfate and sectioned for histology. After 9 weeks the qualitative intrastent luminal diameter was fairly uniform in both the DES and the BMS. The thickness of neointima was similar in both groups. The number of vasa vasorum in the sirolimis DES increased compared with the BMS (P < 0.05). An increased number of vasa vasorum produced by the DES when compared with the BMS shows a difference in response to local vessel injury in rabbits. This result suggests that vasa vasorum may play a role in the persistent inflammation generated by sirolimis‐coated stents.     

Response of spider leg veins to pulsed diode laser (810 nm): a clinical,histological and remission spectroscopy study

BACKGROUND: Spider leg veins are common. Their treatment with laser or intensed light therapy shows generally variable success rates and often adverse side effects such as hyper‐ or hypopigmentation. This study was performed to investigate whether pulsed diode laser (810?nm) treatment is effective and safe.

METHODS: Thirty‐five female patients with spider leg veins were included in this prospective trial. They were treated twice with a pulsed diode laser (810?nm; spot size 12?mm, frequency 2–4?Hz, pulse width 60?msec, fluence 80–100?Jcm^?2). Laser therapy was performed on day 0 and day 14. Clinical assessments were carried out before and immediately after the first laser therapy, after 2 weeks, 8 weeks, and one year. Skin biopsies were taken before and immediately after the first laser treatment, and after 10 weeks. Contact‐free remittance spectroscopy was performed before laser treatment, immediately after the first treatment, after 2 weeks and 8 weeks.

RESULTS: After the first treatment 15 patients showed a complete disappearance (CR) of spider leg veins; in the remaining 20 patients a remarkable improvement (RI) was noted (n=35). After six months of follow‐up CR was seen in 6 patients, RI in 6, a stable situation in 9, and scar formation in 1 patient (n=21). The effect was almost completely stable during one year of follow‐up. The examination of histological specimens before and after laser treatment showed no cellular inflammatory reaction. The mean vascular area was significantly reduced after the first (p<0.05) and after the second (p<0.05) laser treatment. Spectral analysis showed a marked decrease of peaks for oxygenized haemoglobin immediately after laser treatment and during the follow‐up. Safety profile was excellent without purpuric reaction or pigmentary changes. Mild scarring was observed in two patients at the end of follow‐up.

CONCLUSIONS: Pulsed diode laser therapy (810?nm) is an effective and safe treatment option for spider leg veins. The effects can be seen immediately. Objective monitoring by non‐invasive remission spectroscopy and histology of biopsy specimens demonstrates selectivity of the laser action.     

Are there differences in the biochemical profile of bilateral normal testes? A 3.0 T 1H-MR spectroscopy study

Bilateral normal testes asymmetry represents an interesting phenomenon. The aim was to assess possible differences in the biochemical profile of bilateral normal testes by 3.0 T proton magnetic resonance spectroscopy (1H-MRS). Twenty-one men were examined with scrotal 3.0 T MRI, including a single-voxel point-resolved spectroscopy sequence. MR spectra were obtained by placing a volume of interest in the middle of each normal testis. Normalised metabolite concentrations, defined as ratios of the calculated metabolite concentrations relative to creatine (Cr) concentration, were compared between bilateral normal testes using Mann–Whitney U test. 1H-MRS allowed the detection of certain testicular metabolites, including total choline, Cr, myo-inositol, Glx, total lipids and macromolecules resonating at 0.9, 1.3 and 2.0 ppm. Normal left testis had higher median normalised concentrations of Glx (p = .002) and lactate (p = .041) compared with the normal right testis. Differences in concentrations of Glx were attributed to differences in glutamate (p = .020). Normal testes asymmetry is confirmed in this study by differences in the biochemical testicular profile, as assessed by 3.0 T 1H-MRS. Increase in levels of glutamate and lactate in normal left testis should be correlated with changes in metabolic pathways, specifically glycometabolism and amino acid metabolism.     

Diffuse periventricular leukomalacia in preterm children: assessment of grey matter changes by MRI

Background  

Preterm children may have cognitive deficits and behavioural disorders suggestive of grey matter (GM) injury. The prevalence is higher in preterm children with diffuse periventricular leukomalacia (dPVL).     

Voxel-based diffusion tensor imaging detects pyramidal tract degeneration in primary lateral sclerosis

Objective

Primary lateral sclerosis (PLS) is a progressive degenerative disorder affecting upper motor neurons and requires a clinical diagnosis. Diffusion tensor imaging (DTI) is a quantitative method for assessing white matter fibre integrity. The purpose of the study was to evaluate the involvement of upper motor neurons by using DTI in PLS.

Methods

A patient with PLS was compared with eight age-matched controls. Differences in fractional anisotropy (FA) index were assessed using DTI on a voxel-by-voxel basis.

Results

Decreased FA was observed in the proximal part of the pyramidal tract bilaterally, which indicated degeneration of the pyramidal cells.

Conclusion

Voxel-based DTI could be used as an objective marker for detecting upper motor neuron degeneration in PLS.Primary lateral sclerosis (PLS) is an adult onset, non-hereditary degenerative disorder of the upper motor neuron related to a selective loss of precentral pyramidal neurons. Ιt is characterised by progressive spinobulbar spasticity owing to pyramidal tract degeneration, but preservation of the anterior horn motor neurons and no involvement of the lower motor neuron [1–4]. Currently there is no defining test or disease marker; thus, the diagnosis is usually made based on clinical presentation [1, 2].Diffusion tensor imaging (DTI) is an MRI technique that provides information about white matter fibre orientation and integrity in vivo based on the principles of free water molecules movement. Water molecules move in a random manner (isotropic diffusion); however, the presence of obstacles, such as axonal membranes and myelin sheaths, restrict the motion in a particular direction resulting in anisotropic diffusion. The fractional anisotropy (FA) index is a measure of the degree of directionality of diffusion [5, 6]. The assessment of FA has been used as a measure of white matter degeneration in many diseases as it can detect and quantify the degeneration of fibres along white matter tracts [5, 6]. The method that is usually used is the region of interest (ROI) approach [7]. Nowadays, an automated method of analysis is used for a voxel-wise comparison of DTI data throughout the whole brain [8, 9].In this report a single case of PLS was studied using DTI on a voxel-by-voxel comparison with a control group to detect upper motor neuron involvement.     

世界胃肠病学组织全球指南——发展中国家幽门螺杆菌感染

世界上有一半人口感染幽门螺杆菌（H．pylori）,其感染率因地理位置、种族、年龄和社会经济状况不同而存在很大差异．在发展中国家较高．发达国家较低。但总体而言,近年世界许多地区的H．pylori感染率均呈下降趋势。