Evaluation of popliteal arteries with CT angiography in popliteal artery entrapment syndrome

BACKGROUND

Popliteal artery entrapment is an uncommon clinical entity that occurs due to compression of the popliteal artery by adjacent muscle and tendinous structures. Early diagnosis should be established through a combined approach of careful physical examination and history-taking, duplex ultrasonography, and CT angiography.

PATIENTS AND METHODS

We have studied retrospectively 16 patients of popliteal artery entrapment syndrome, 9 men and 7 women. All patients were scanned with a scanner Picker PQ 5000 after bolus injection of nonionic contrast medium and they all underwent a two-part examination first, with the knee in a neutral position, and, second, with the knee hyperextended.

RESULTS

At the second phase of the examination 3 patients showed normal findings, 10 patients have shown mild stenosis of the popliteal artery or more severe stenosis due to compression, 2 patients have exhibited bilateral stenosis and 1 patient has also showed popliteal venous compression.

CONCLUSION

CT angiography images and three-dimensional images are useful not only for depiction of the arterial changes but also identification of the abnormal anatomic structures responsible for the entrapment.

Enhancement of Virchow-Robin Spaces

Virchow-Robin spaces are enclosed spaces filled with interstitial fluid and covered with pia that accompany arteries, arterioles, veins and venules as they perforate the brain. They are round, linear or punctuate areas depending on the image that parallel cerebrospinal fluid attenuation or signal intensity. They are classically described as isointense to cerebrospinal fluid on images obtained with all pulse sequences. They appear hypointense relative to brain on T1-weighted MR scans and present a high signal intensity on T2-weighted MR scans. They also show complete signal suppression on fluid-attenuated inversion recovery (FLAIR) scans and no enhancement after intravenous contrast administration. However, many pathologic states result in abnormal dilation with an increased number of Virchow-Robin spaces visible on MRI imaging and many pathological conditions cause the spaces to enhance. The purpose of this study is to present the major causes of Virchow-Robin enhancement.

Enhancement of robin-virchow spaces MRI evaluation

The perivascular spaces are normally microscopic. Even in normal brain some Robin-Virchow spaces are usually seen in the area of substantia innominata at the level of anterior commissure. Many pathologic states result in abnormal dilatation with an increased number of spaces visible on MRI imaging. Dilatation is most commonly associated with anterior abnormalities that arise due to aging, diabetes, hypercholesterolemia, smoking, hypertension and other vascular risk factors. The precise etiology of dilatation is currently unknown.

Role of rescue IVF-ET treatment in the management of high response in stimulated IUI cycles

Rescue in-vitro fertilisation and embryo transfer (IVF-ET) has been used in high response gonadotrophin intrauterine insemination (IUI) cycles to minimise the risks of ovarian hyperstimulation and multiple gestation. Such unplanned IVF treatment increases the cost of treatment. But can this added cost and the risks associated with IVF be justified? We present our experience with this treatment using clinical pregnancy and live birth rates as the primary outcomes. Between 1998 to 2001, 40 women undergoing IUI cycles who over responded (>3 follicles measuring >15 mm in diameter on the planned day of hCG administration) to gonadotrophin were offered the choice of conversion to IVF-ET or cancel the cycle. 17/40 declined rescue IVF/ET and had their cycles cancelled. 23/40 converted to IVF/ET and underwent transvaginal oocyte retrieval. 21/23 had embryo transferred. The clinical pregnancy and live birth rates were 52% and 48%, respectively. Rescue IVF-ET offers excellent clinical pregnancy and live birth rates in high responders. However, affordability can be an obstacle in the utilization of this treatment option.

Biocompatibility of two commercial forms of mineral trioxide aggregate

AIM

To examine the biocompatibility of two commercial forms of mineral trioxide aggregate (MTA), by evaluating the morphology of an established cell line.

METHODOLOGY

The two cements were cast on glass cover slips and cured for 1 or 28 days. Saos-2 osteosarcoma cells were trypsinized and seeded at a density of 1 x 10(5) cells and were then placed in medium over the material-coated coverslips for 1, 5 and 7 days. After these time intervals the media were discarded and the cells fixed. Cell morphological investigation was performed by scanning electron microscopy at various magnifications ranging from x 250 to x 500. The biocompatibility of cement constituents, alusilicate flux and bismuth oxide was also investigated.

RESULTS

All cement samples cured for 1 day showed a confluent cell monolayer after 5 and 7 days. The response to both materials was similar. Materials cured for 28 days showed incomplete cell confluence after 1 and 5 days. Alusilicate flux and bismuth oxide did not demonstrate biocompatibility.

CONCLUSIONS

The 1-day cured samples of two commercial forms of MTA showed good biocompatibility. However, the 28-day cured samples were less biocompatible after 1 and 5 days.

The effects of serine proteinase inhibitors on bone resorption in vitro

The aims of this study were to identify the role and sites of action of serine proteinases (SPs) in bone resorption, a process which involves a cascade of events, the central step of which is the removal of bone matrix by osteoclasts (OCs). This resorbing activity, however, is also determined by recruitment of new OCs to future resorption sites and removal of the osteoid layer by osteoblasts (OBs), which enables OCs to gain access to the underlying mineralized bone. The resorption systems we have studied consisted of (i) neonatal calvarial explants, (ii) isolated OCs cultured on ivory slices, (iii) mouse OBs cultured on either radiolabelled type I collagen films or bone-like matrix, (iv) bone marrow cultures to assess OC formation and (v) 17-day-old fetal mouse metatarsal bone rudiments to assess OC migration and fusion. Two separate SP inhibitors, aprotinin and alpha(2)-antiplasmin dose-dependently inhibited (45)Ca release from neonatal calvarial explants: aprotinin (10(-6) M) was the most effective SP inhibitor, producing a maximum inhibitory effect of 55.9%. Neither of the SP inhibitors influenced either OC formation or OC resorptive activity. In contrast, each SP inhibitor dose-dependently inhibited OB-mediated degradation of both type I collagen fibrils and non-mineralized bone matrix. In 17-day-old metatarsal explants aprotinin produced a 55% reduction in the migration of OCs from the periosteum to the mineralized matrix after 3 days in culture but after 6 days in culture aprotinin was without effect on OC migration. Primary mouse osteoblasts expressed mRNA for urokinase type plasminogen activator (uPA), tIssue type plasminogen activator (tPA), the type I receptor for uPA, plasminogen activator inhibitor types I and II and the broad spectrum serine proteinase inhibitor, protease nexin I. In situ hybridization demonstrated expression of tPA and uPA in osteoclasts disaggregated from 6-day-old mouse long bones. We propose that the regulation of these various enzyme systems within bone tIssue determines the sites where bone resorption will be initiated.

Interleukin-6 (IL-6), IL-1, receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin production by human osteoblastic cells: comparison of the effects of 17-beta oestradiol and raloxifene

Oestrogen inhibits bone resorption, at least in part, by regulating the production of several cytokines, including interleukin-6 (IL-6), IL-1, receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) by cells of the osteoblastic lineage. The selective oestrogen receptor modulator raloxifene (RAL) acts on bone in a similar manner to oestrogen, although the mechanisms of action of RAL on osteoblasts still remain unclear. We investigated and compared the effects of 17-beta oestradiol (E(2)) and RAL on the regulation of IL-6, IL-1, RANKL and OPG in vitro in primary human osteoblastic (HOB) cells and in an immortalised clonal human bone marrow stromal cell line (HCC1) with osteoblastic characteristics. We tested E(2) and RAL at concentrations ranging from 10(-12) to 10(-6) M. IL-6, IL-1alpha and IL-1beta, OPG and RANKL were measured by ELISA. RANKL and OPG mRNA steady state level was assessed by quantitative PCR analysis. Both E(2) and RAL led to a significant reduction in IL-6 production in the HOB cells, although the effect was more marked with E(2) (P<0.05). IL-1alpha and IL-1beta also decreased significantly following treatment with E(2) and RAL in the HCC1 cells (E(2) (10(-8), 10(-7) and 10(-6) M), % reduction (means+/-S.E.M.) compared with vehicle-treated cells - IL-1alpha: 84+/-7.4, 70.8+/-2.9*, 78.2+/-4.8*; IL-1beta: 79+/-10, 72.8+/-8.2*, 66.6+/-2.8*; RAL (10(-8), 10(-7) and 10(-6) M) - IL-1alpha: 72.4+/-5*, 79+/- 5.2*, 102+/-7.7; IL-1beta: 67.9+/-3.2*, 69+/-2.5*, 73.8+/- 6.2*; *P<0.05). OPG protein concentration decreased significantly in a dose-dependent manner following treatment with E(2) and RAL (% reduction E(2) (10(-8), 10(-7) and 10(-6) M) - HOB: 72.5+/-8.4*, 80+/-6.7*, 62.8+/-8.9*; HCC1: 109+/-4, 98.8+/-6, 54.5+/-3.4*; RAL (10(-8), 10(-7) and 10(-6) M) - HOB: 81.5+/-5.5*, 62.7+/-7.4*, 55.2+/-10.9*; HCC1: 92.7+/-7.4, 67+/-12.2*, 39+/-4.5*; *P<0.05). In the HCC1 cells, RANKL protein did not change significantly following E(2). In contrast, a significant reduction in RANKL was seen with RAL at 10(-7) and 10(-6) M (66+/-6.4% and 74+/-3% respectively). There was no change in OPG mRNA expression following E(2) or RAL in the HCC1 cells, although in the HOB cells we observed a significant reduction in OPG mRNA. RANKL mRNA decreased significantly in the HCC1 cells following RAL (10(-8), 10(-7)and 10(-6) M) treatment (% change from controls: 52+/-2*, 62+/-1*, 53+/-5.8*; *P<0.05). Similar results were seen in the HOB cells with RAL at 10(-6) M (RANKL mRNA: 72+/-5.5, P<0.05). In addition, there was a significant decrease in the RANKL/OPG ratio after RAL at 10(-6) M (HOB: 65.6+/-5*, HCC1: 56.9+/-20*; *P<0.05). RANKL/OPG ratio did not change significantly in the HCC1 cells following E(2). However, in contrast to RAL, we observed an increase in the RANKL/OPG ratio in the HOB cells following treatment with E(2). In conclusion, the study shows that RAL and E(2) have divergent cell-specific effects on the regulation of cytokines. The data also suggest that, in contrast to E(2), RAL may exert its anti-resorptive actions, at least in part, via the RANKL/OPG pathway. Further in vivo studies are required to confirm this.

Spontaneous disappearance of a normal adnexa associated with a contralateral polycystic-appearing ovary

BACKGROUND

Absence of the adnexa may be congenital or acquired. However, the etiology is often uncertain.

CASE

A 27-year-old woman presented with a 3-year history of subfertility. Her irregular menstruation was associated with acne vulgaris, alopecia, and elevated body mass index. Transvaginal ultrasonography of the pelvis showed a normal uterus, a normal right ovary, but a polycystic-appearing left ovary. A hysterosalpingogram demonstrated a normal uterine cavity, prompt filling and spilling of contrast material from the left fallopian tube, but no filling on the right. Subsequent laparoscopy showed an unexpected absence of right adnexa and presence of a solitary rounded free-floating mass enshrouded in the omentum. She did not have a history of abdominal pain or surgery.

CONCLUSION

The evidence suggests that the patient might have had an asymptomatic infarction of the right adnexa.

An evaluation of accelerated Portland cement as a restorative material

Biocompatibility of two variants of accelerated Portland cement (APC) were investigated in vitro by observing the cytomorphology of SaOS-2 osteosarcoma cells in the presence of test materials and the effect of these materials on the expression of markers of bone remodelling. Glass ionomer cement (GIC), mineral trioxide aggregate (MTA) and unmodified Portland cement (RC) were used for comparison. A direct contact assay was undertaken in four samples of each test material, collected at 12, 24, 48 and 72 h. Cell morphology was observed using scanning electron microscopy (SEM) and scored. Culture media were collected for cytokine quantification using enzyme-linked immunosorbent assay (ELISA). On SEM evaluation, healthy SaOS-2 cells were found adhering onto the surfaces of APC variant, RC and MTA. In contrast, rounded and dying cells were observed on GIC. Using ELISA, levels of interleukin (IL)-1beta, IL-6, IL-18 and OC were significantly higher in APC variants compared with controls and GIC (p<0.01), but these levels of cytokines were not statistically significant compared with MTA. The results of this study provide evidence that both APC variants are non-toxic and may have potential to promote bone healing. Further development of APC is indicated to produce a viable dental restorative material and possibly a material for orthopaedic

Long term safety of fluoroscopically guided selective salpingography and tubal catheterization

BACKGROUND

The irradiation of the ovaries of reproductive age women during fluoroscopically guided selective salpingography and tubal catheterization has raised concern about the safety of the procedure. In addition to the risk of cancer induction, which exists with the irradiation of all tissues, with the gonads, the induction of hereditary disorders is possible. The objective of this study was to estimate these risks and present them in a clinically meaningful way.

METHODS

Retrospective analysis was undertaken of 366 consecutive cases of selective salpingography and tubal catheterization performed at the Birmingham Women's Hospital, UK. The radiation doses of different types of procedure were compared with the background annual radiation dose. The risks of cancer and genetic disorders induction were calculated using conversion coefficients published by the International Commission on Radiological Protection.

RESULTS

The radiation dose women were exposed to during selective salpingography and tubal catheterization under fluoroscopic guidance was a fraction of the background annual radiation dose. The excess lifetime risks of cancer and hereditary disorders were in the order of four to 13 and two to six per million procedures respectively.

CONCLUSIONS

The long term risks of selective salpingography and tubal catheterization under fluoroscopic guidance are low.

X-rays modulate extracellular matrix in vivo

X-rays have an antiangiogenic effect in the chicken embryo chorioallantoic membrane (CAM) model of in vivo angiogenesis. Our study demonstrates that X-rays induce an early apoptosis of CAM cells, modulate the synthesis and deposition of extracellular matrix (ECM) proteins involved in regulating angiogenesis and affect angiogenesis induced by tumour cells implanted onto the CAM. Apoptosis was evident within 1-2 hr, but not later than 6 hr after irradiation. Fibronectin, laminin, collagen type I, integrin alpha(v)beta3 and MMP-2 protein amounts were all decreased 6 hr after irradiation. In contrast, collagen type IV, which is restricted to basement membrane, was not affected by irradiation of the CAM. There was a similar decrease of gene expression for fibronectin, laminin, collagen type I and MMP-2, 6 hr after irradiation. The levels of mRNA for integrin alpha(v)beta3 and collagen type IV were unaffected up to 24 hr after irradiation. The decrease in both protein and mRNA levels was reversed at later time points and 48 hr after irradiation, there was a significant increase in the expression of all the genes studied. When C6 glioma tumour cells were implanted on irradiated CAMs, there was a significant increase in the angiogenesis induced by tumour cells, compared to that in non-irradiated CAMs. Therefore, although X-rays have an initial inhibitory effect on angiogenesis, their action on the ECM enhances new vessel formation induced by glioma cells implanted on the tissue.

Should ICSI be the treatment of choice for all cases of in-vitro conception? Considerations of fertilization and embryo development, cost effectiveness and safety

There is now considerable discussion whether intracytoplasmic sperm injection (ICSI) should be used in all cases of IVF. A critical and balanced view of the current literature is presented. The difficult question is how to identify men with apparently normal semen who are likely to fail to achieve a pregnancy using IVF. In conclusion, from both the safety and scientific viewpoint, ICSI should only be used in cases where success at IVF is regarded as unlikely.

Aspirin for the prevention of preeclampsia in women with abnormal uterine artery Doppler: a meta-analysis

OBJECTIVE

To determine the effectiveness of aspirin to prevent preeclampsia in women identified as high risk for preeclampsia by an abnormal second-trimester uterine artery Doppler examination.

DATA SOURCES

Searches were conducted in MEDLINE, Embase, the Cochrane Controlled Trials Register, and Science Citation Index for randomized trials published from 1966 to 2000, using the following medical subject headings and key words: "aspirin," "antiplatelet*," "salicyl*," "acetylsalicyl*," "platelet aggregation inhibitors," "ultrasonography," "ultraso*," and "Doppler."

STUDY SELECTION

We included all randomized trials that evaluated the effectiveness of aspirin compared with placebo or no treatment in women with an abnormal uterine artery Doppler and that reported clinically relevant perinatal and maternal outcomes. Study selection, quality assessment, and data extraction were performed in duplicate.

TABULATION, INTEGRATION, AND RESULTS

There were five relevant trials. Pooling of results from these trials showed a significant benefit of aspirin in reducing preeclampsia (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.32, 0.95). The baseline risk of preeclampsia in women with abnormal uterine artery Doppler was 16%, and the number of women needed to be treated with aspirin to prevent one case of preeclampsia was 16 (95% CI 8, 316). Women on aspirin had babies who were on average 82 g heavier than controls, but this result did not reach statistical significance (weighted mean difference 81.5, 95% CI 40.27, 203.27).

CONCLUSION

Uterine artery Doppler assessment identifies high-risk women in whom aspirin therapy results in a significant reduction in preeclampsia.

Critical appraisal in clinical practice: sometimes irrelevant, occasionally invalid

A core activity of evidence-based practice is the search for and appraisal of evidence on specific clinical issues. Clinicians vary in their competence in this process; we therefore developed a 16-item checklist for quality of content (relevance and validity) and presentation (useability, attribution, currency and contact details). This was applied to a set of 55 consecutive appraisals conducted by clinicians and posted at a web-based medical journal club site. Questions were well formulated in 51/55 (92%) of the appraisals. However, 22% of appraisals missed the most relevant articles to answer the clinical question. Validity of articles was well appraised, with methodological information and data accurately extracted in 84% and accurate conversion to clinically meaningful summary statistics in 87%. The appraisals were presented in a useable way with appropriate and clear bottom-lines stated in 95%. The weakest link in production of good-quality critical appraisals was identification of relevant articles. This should be a focus for evidence-based medicine and critical appraisal skills.