Acute vertebral body compression fractures: discrimination between benign and malignant causes using apparent diffusion coefficients

Diffusion weighted MRI was performed on patients with acute vertebral body compression. The usefulness of the apparent diffusion coefficient (ADC) in differentiating between benign and malignant fractures was evaluated. A total of 49 acute vertebral body compression fractures were found in 32 patients. 25 fractures in 18 patients were due to osteoporosis, 18 fractures in 12 patients were histologically proven to be due to malignancy, and 6 fractures in 2 patients were due to tuberculosis. Signal intensities on T(1) weighted, short tau inversion recovery (STIR) and diffusion weighted images were compared. ADC values of normal and abnormal vertebral bodies were calculated. Except for two patients with sclerotic metastases, benign acute vertebral fractures were hypointense and malignant acute vertebral fractures were hyperintense with respect to normal bone marrow on diffusion weighted images. Mean combined ADCs (ADC(cmb); average of the combined ADCs in the x, y and z diffusion directions) were 0.23 x 10(-3) mm(2) s(-1) in normal vertebrae, 0.82 x 10(-3) mm(2) s(-1) in malignant acute vertebral fractures and 1.94 x 10(-3) mm(2) s(-1) in benign acute vertebral fractures. The differences between ADC(cmb) values were statistically significant (p<0.001). The ADC is useful in differentiating benign from malignant acute vertebral body compression fractures, but there may be overlapping ADC values between malignant fractures and tuberculous spondylitis.

Factorial randomised controlled trial of glucocorticoids and combination disease modifying drugs in early rheumatoid arthritis

OBJECTIVE

Treating early active rheumatoid arthritis (RA) with disease modifying antirheumatic drug (DMARD) monotherapy achieves incomplete outcomes and intensive treatment seems preferable. As the relative benefits of combining two DMARDs, one DMARD with glucocorticoids and two DMARDs with glucocorticoids are uncertain we defined them in a factorial trial.

METHODS

A 2-year randomised double-blind factorial trial in patients with RA within 2 years of diagnosis treated with methotrexate studied the benefits of added ciclosporin, 9 months intensive prednisolone or both (triple therapy). The primary outcome was the number of patients with new erosions. Secondary outcomes included Larsen's x-ray scores, disability, quality of life and adverse events.

FINDINGS

1391 patients were screened and 467 randomised. Over 2 years 132 (28%) changed therapy and 88 (19%) were lost to follow-up. The number of patients with new erosions was reduced by nearly half by adding ciclosporin or prednisolone (p = 0.01 and 0.03); both treatments reduced increases in Larsen's x-ray scores by over 2 units (p = 0.008 and 0.003). A further reduction in erosive damage was seen with combined use of both treatments. Their effects on erosive damage appeared independent. Triple therapy reduced disability and improved quality of life compared with methotrexate; ciclosporin and prednisolone acted synergistically. More patients withdrew because of adverse events with triple therapy, without an increase in serious adverse effects.

CONCLUSIONS

This study confirms the existence of a "window of opportunity" in early RA, when intensive combination therapy produces sustained benefits on damage and disability. Although methotrexate-prednisolone combinations reduce erosive damage, the synergistic effect of two DMARDs is needed to improve quality of life.

Fas/Fas ligand-mediated death pathway is involved in oxLDL-induced apoptosis in vascular smooth muscle cells

Oxidized low-density lipoprotein (oxLDL) is a potent inducer of apoptosis for vascular cells. In the present study, we demonstrate that the expression of death mediators, including p53, Fas, and Fas ligand (FasL) was substantially upregulated by oxLDL in cultured vascular smooth muscle cells (SMCs). The induction of these death mediators was time dependent and was accompanied by an increase in apoptotic death of SMCs following oxLDL treatment. Two oxysterols, 7beta-hydroxycholesterol and 25-hydroxycholesterol, were also effective to induce the expression of death mediators and apoptosis. alpha-Tocopherol and deferoxamine significantly attenuated the induction of death mediators and cell death induced by oxLDL and oxysterols, suggesting that reactive oxygen species are involved in triggering the apoptotic event. Incubation of cells with FasL-neutralizing antibody inhibited the oxLDL-induced cell death up to 50%. Furthermore, caspase 8 and caspase 3 activities were induced time dependently in SMCs following oxLDL treatment. Collectively, these data suggest that the Fas/FasL death pathway is activated and responsible for, at least in part, the apoptotic death in vascular SMCs upon exposure to oxLDL.

Little effect of praziquantel or artemisinin on clonorchiasis in Northern Vietnam. A pilot study

The first choice for treatment of Clonorchis sinensis infections is praziquantel. Experimental data suggest that artemisinin derivatives are active against C. sinensis. The efficacy of both drugs against clonorchiasis was evaluated in a pilot study in clonorchiasis patients in an endemic area in the North of Vietnam. Twenty-one patients received praziquantel 25 mg/kg o.d. for three days, the regular regimen in that area, and 21 patients were treated with artemisinin 500 mg b.i.d. for 5 days. Faecal egg counts were performed before as well as 6 days and 5 weeks after treatment. In the praziquantel group the faecal egg count decreased significantly from a mean value of 1632 eggs per gram faeces (epg) to 37 epg 5 weeks after treatment (P < 0.01) but, surprisingly, the eradication rate (95% confidence limit) at week 5 was only 29% (11-52%). In the artemisinin-treated group the reduction of the egg count was insignificant: from 1103 to 542 epg (P > 0.05). The proportion of patients (95% c.l.) with C. sinensis eggs in their stool on week 5 was 90% (70-99%) in the artemisinin group and 71% (48-89%) in the praziquantel group (P > 0.05) and the eradication rate (95% c.l.) at week 5 was only 10% (1-30%). With a sensitivity of detection of eggs in stool > 0.89, this implies a statistically significant but clinically unsatisfactory reduction for treatment with praziquantel. Sensitivity is probably less. For artemisinin there was no significant reduction. In conclusion, for human clonorchiasis in the North of Vietnam, the efficacy of praziquantel 25 mg/kg o.d. for 3 days was unsatisfactory and artemisinin for 5 days is not an effective alternative.

Discrimination of an infected brain tumor from a cerebral abscess by combined MR perfusion and diffusion imaging

The aim of this study was to investigate the signal characteristics of the abscess wall and tumor wall on diffusion-weighted and perfusion-weighted images and thus to evaluate the feasibility of using combined MR diffusion and perfusion imaging to differentiate pyogenic cerebral abscess from infected brain tumor. The tumor wall of various types of cystic or necrotic brain tumor was significantly hyperintense relative to that of cerebral abscess wall on both diffusion-weighted images and regional cerebral blood volume maps. Sixteen patients who had cerebral masses with large cystic or necrotic cavities were imaged to generate diffusion-weighted images and regional cerebral blood volume maps using single-shot echoplanar imaging (EPI) pulse sequences. Apart from qualitative analysis, apparent diffusion coefficients (ADC) as well as regional cerebral blood volume (rCBV) ratios were calculated from the abscess wall and peripheral tumor wall and comparison was made by using Student's t-test. The tumor wall of various types of cystic or necrotic brain tumor had significantly lower ADCs relative to those of the abscess wall (P<0.005) and thus appeared relatively hyperintense on diffusion-weighted images. The mean rCBV ratio relative to normal white matter (2.90+/-0.62) of the peripheral tumor wall of various types of cystic or necrotic brain tumor were significantly larger than the mean rCBV ratio (0.45+/-0.11) of the pyogenic cerebral abscess wall (P<0.001) by Student's t-test. It is concluded that the combined MR diffusion and perfusion imaging might be capable of differentiating an infected brain tumor from a pyogenic cerebral abscess.

Tarsal tunnel syndrome caused by talocalcaneal coalition

Tarsal tunnel syndrome caused by talocalcaneal coalition is uncommon. We presented the ultrasonography (US) and magnetic resonance imaging findings of this disease. This is, to our knowledge, the first case report describing the US findings in tarsal tunnel syndrome caused by talocalcaneal coalition.

Radiation dose reduction in paediatric cranial CT

BACKGROUND

There is no consensus about the optimal milliamperage-second (mAs) settings for computed tomography (CT). Most operators follow the recommended settings of the manufacturers, but these may not be the most appropriate settings.

OBJECTIVE

To determine whether a lower radiation dose technique could be used in CT of the paediatric brain without jeopardising the diagnostic accuracy of the images.

MATERIALS AND METHODS

A randomised prospective trial. A group of 53 children underwent CT using manufacturer's default levels of 200 or 250 mAs; 47 underwent scanning at 125 or 150 mAs. Anatomical details and the confidence level in reaching a diagnosis were evaluated by two radiologists in a double-blinded manner using a 4-point scoring system.

RESULTS

For both readers there was no statistically significant difference in the confidence level for reaching a diagnosis between the two groups. The 95 % confidence intervals and P values were -0.9-1.1 and 0.13 (reader 1) and -1.29-1.37 and 0.70 (reader 2), respectively. Reliability tests showed the results were consistent.

CONCLUSIONS

The recommended level may not be the optimum setting. Dose reduction of 40 % is possible on our system in paediatric brain CT without affecting the diagnostic quality of the images.

Cytomegalovirus remains viable in naturally infected breast milk despite being frozen for 10 days

Cytomegalovirus culture positive breast milk was obtained from four mothers of very premature babies. The milk was stored at 0-5 degrees C in a domestic refrigerator for 48 hours or frozen for different durations at -20 degrees C. Cytomegalovirus survived in breast milk despite being frozen for 10 days at -20 degrees C.

A Canadian survey of prophylactic antibiotic use among hip-fracture patients

OBJECTIVE

To study how surgical prophylactic antibiotics (SPAs) were utilized in the perioperative management of surgery for hip fractures.

DESIGN

Retrospective chart review of randomly selected medical records.

SETTING

Twenty-two hospitals (teaching, nonteaching, community, and large urban referral centers) from across Canada.

PATIENTS

Patients admitted in 1990 with a diagnosis of hip fracture.

METHODS

Complete medical records of 438 patients were examined; 352 cases who underwent surgical repair of a fractured hip with insertion of prosthetic material were included in analysis. Perioperative SPA use was assessed by abstracting the agent(s) chosen, dosages, time given with respect to the incision, and duration of postoperative use. Fourteen patient and process-of-care variables related to SPA were examined.

RESULTS

247 (70%) of 352 cases did not receive a dose of SPA 2 hours preoperatively. Ten percent of preoperative SPA was administered either too early or during the procedure. In 91 (39%) of 231 cases receiving SPA, the first dose was not administered until the end of the procedure. Preoperative SPA consisted of a parenteral first-generation cephalosporin for 94% of cases. SPAs were continued more than 24 hours postoperatively in 78% of cases. Lack of a written order for SPA, being a nonteaching hospital, and shorter duration of surgical procedure were predictive of failure to receive SPA in an effective manner.

CONCLUSIONS

Most hip-fracture-surgery patients did not receive effective antibiotic prophylaxis as required to prevent serious wound infections. This important variable can be included for surveillance, so that corrective measures can be taken to assure effective prophylactic antibiotic administration.

Clinical and radiological features of biliary papillomatosis

Biliary papillomatosis is a rare disease with strong potential for malignant degeneration. Diagnosis is often not easy and most are made intraoperatively. In the present study, five patients with biliary papillomatosis admitted between 1990 and 1997 were reviewed. Their clinical presentation, radiological and biochemical findings were analysed. The aim of the study was to discern a set of characteristic features that would enable an early diagnosis. All of the five patients presented with recurrent episodes of acute cholangitis and epigastric pain with raised serum alkaline phosphatase. Imaging modalities including ultrasound, CT, endoscopic retrograde cholangio-pancreatogram, MRI and magnetic resonance cholangio-pancreatogram were reviewed. Salient imaging features included a dilated biliary tree with multiple ill-defined and fuzzy filling defects or endoluminal frond-like mass lesions. In conclusion, biliary papillomatosis is a rare but important cause of biliary obstruction with relapsing cholangitis and obstructive jaundice. With a healthy index of suspicion, the diagnosis can be reached when the above features are available.

Idiopathic pulmonary artery aneurysm: digital subtraction pulmonary angiography grossly underestimates the size of the aneurysm

Pulmonary artery aneurysm is a rare disease entity. The majority of cases are associated with congenital cardiovascular diseases, infection, and trauma; idiopathic pulmonary artery aneurysm is extremely rare. Although conventional and digital subtraction pulmonary angiography remains as the imaging modality of choice for the pulmonary vessels, it is invasive and sometimes may be inaccurate. With the advent of spiral computed tomographic angiography (CTA), pulmonary artery aneurysm can be diagnosed noninvasively and accurately. We report a case of a 68-year-old man with idiopathic pulmonary artery aneurysm of the descending branch of right pulmonary artery where the true caliber of the aneurysm was significantly underestimated in the digital subtraction pulmonary angiography. The literatures of this rare condition are reviewed with the emphasis on the application of CTA in this disease.

Effect of cervical vagotomy on catecholaminergic neurons in the cranial division of the parasympathetic nervous system

This study provides evidence of catecholaminergic neurons in the cranial division of the parasympathetic nervous system. Presumptive catecholaminergic preganglionic neurons in the dorsal motor nucleus of the vagus (DMX) were revealed by a clearcut depletion of intracellular catecholamine-synthesizing enzyme immunoreactivity induced by unilateral cervical vagotomy and identified on tissues immunocytochemically processed for tyrosine hydroxylase (TH), dopamine beta-hydroxylase (D beta H) or phenylethanolamine N-methyltransferase (PNMT). This experimental design was essential because of the recent failure in two species to reproduce data previously obtained in double-label (combined immunocytochemical-retrograde transport) studies. Vagotomy data confirmed three spatially-segregated populations of catecholaminergic visceromotor neurons in the DMX. These cell bodies were morphologically identical to preganglionic neurons observed on alternate tissues stained for Nissl substance or immunostained for choline acetyltransferase (ChAT), the enzyme biosynthesizing acetylcholine. Neurons in the central and medial DMX demonstrated fall-off of TH-like immunoreactivity (LI) ipsilateral to the vagotomy at levels caudal to the obex. This cell group is assumed to be predominantly dopaminergic since relatively few neurons at this level of the DMX expressed D beta H-LI and none were immunostained for PNMT. A second population of immunoreactive neurons, concentrated in the rostral-lateral region of the DMX, was depleted of D beta H-LI on the ipsilateral side but did not express PNMT. These visceromotor neurons may, therefore, biosynthesize noradrenaline and belong to the rostral pole of the A2 area. A third population of presumptive adrenergic vagal dorsomotor neurons in the rostral-medial DMX was depleted of TH-, D beta H- and PNMT-LI at levels of the ipsilateral nucleus anterior to obex. Patterns of depletion of cytoplasmic enzyme-immunoreaction product were identical in all cases irrespective of the site of the transection or the postoperative survival period. Quantitative analysis demonstrated statistically significant loss of immunolabeled neurons in rostral and caudal subgroups of the DMX on the side ipsilateral to the vagotomy. It is concluded that catecholaminergic processes in the vagus nerve, as previously identified by the aldehyde-induced histofluorescence method, may partly arise from the lower brainstem.

Massive Spontaneous Haemopneumothorax and Ecstasy Abuse

A 33-year-old man developed spontaneous haemopneumothorax after taking ecstasy in a ‘rave party’. Massive haemorrhage occurred after chest drainage and decompression. Both the adverse effects of ecstasy and risk behaviours at the party might have contributed to the development of the spontaneous haemopneumothorax.

Digital subtraction in gadolinium-enhanced MR imaging of the brain: a method to reduce contrast dosage

The aim of the study was to investigate the feasibility of using digital subtraction in contrast-enhanced MR imaging of the brain to reduce the MR contrast dosage without jeopardizing patient care. Fifty-two patients with intracranial lesions, either intra-axial or extra-axial, detected by computerized tomography were selected for contrast-enhanced MR imaging with half-dose and full-dose of gadopentetate dimeglumine. The half-dose unsubtracted, full-dose unsubtracted, and half-dose subtracted MR images were visually assessed by counting the number of enhancing brain lesions in the images and quantitatively analyzed by computing their lesion contrast-to-background ratios (CBR). The visual conspicuity of the half-dose subtracted MR images was comparable to that of the full-dose unsubtracted MR images ( p>0.05), whereas the CBR of the half-dose subtracted images was approximately two to three times higher than that of the full-dose unsubtracted images. The half-dose subtracted T1-weighted spin-echo images might be able to replace the conventional standard-dose T1-weighted spin-echo images in MR imaging of the brain.

Monocyte membrane ferritin in hemochromatosis

To further evaluate a possible abnormality in the reticuloendothelial cells in hemochromatosis, the binding of a monoclonal anti-human liver ferritin antibody to monocytes was studied in 19 patients with hemochromatosis, 8 patients with secondary iron overload, 1 patient with hyperferritinemia without iron overload, and 15 normal volunteers. Binding of the antibody to the monocytes was analyzed using a fluorescence-activated cell sorter (FACS). Binding of the anti-ferritin antibody to monocytes was demonstrated in 34.7 +/- 4.5% (mean +/- standard error) of the monocytes in untreated hemochromatosis patients (mean serum ferritin = 2294 +/- 415 micrograms/L), 6.75 +/- 2.03% in treated hemochromatosis patients (mean serum ferritin = 263 +/- 85 micrograms/L), 12.3 +/- 2.7% of the monocytes in the secondary iron overload patients (mean serum ferritin = 2476 +/- 867 micrograms/L), 4.1% in the patient with hyperferritinemia (serum ferritin = 1192) and 4.1 +/- 0.5% of the monocytes in the normal volunteers (mean serum ferritin = 55.2 +/- 11.9 micrograms/L). % binding of anti-ferritin antibody was significantly greater in hemochromatosis patients compared to patients with secondary iron overload (p less than 0.05) despite a comparable degree of iron overload in the secondary iron overload group. The addition of exogenous human ferritin to samples from treated hemochromatosis patients and normal volunteers did not significantly increase the % of monocytes binding anti-ferritin antibody. These results suggest that monocytes from iron-loaded hemochromatosis patients express increased surface ferritin which may represent release of ferritin and a metabolic defect characteristic of hemochromatosis.

Pes varus correction in dachshunds with mini hybrid external skeletal fixators

AIM

To evaluate the clinical and radiographic outcome of pes varus deformity correction in dachshunds managed with acute medial opening wedge osteotomy of the distal tibia and stabilised with a mini hybrid external skeletal fixator (HESF).

METHODS

Surgical correction involved a transverse osteotomy over the premeasured location at the distal tibia and application of a IMEX mini HESF. All corrections were evaluated using centre of rotation and angulation methodology.

RESULTS

Medical records and radiographies of 20 dachshunds (28 pes varus corrections) were reviewed. All osteotomies healed and fixators were removed between 6 and 12 weeks. Lameness resolved in 18 dachshunds (90%) and significantly improved in two dachshunds (10%). Lateral patella luxation (LPL) was detected in 11/28 (39.2%) of the involved pelvic limbs, all of which resolved following pes varus correction. Mean frontal plane alignment (FPA) of the normal and abnormal tibiae were 12.3° valgus (range: 4°-18°) and 25° Varus (range: 16°-41°) respectively. Angular correction ranged between 30° and 50° (Mean: 39°) and the mean post-operative FPA was 13° valgus (range: 5°-21°).

CLINICAL SIGNIFICANCE

Pes varus deformity in dachshunds can be corrected by medial opening wedge osteotomy of the distal tibia stabilised by HESF. Single-session bilateral pes varus corrections can also be performed with minimal morbidity. LPL was commonly detected in dogs with pes varus deformity and all resolved spontaneously following pes varus correction alone.