Analgesic effect of intravenous dexamethasone after volar plate surgery for distal radius fracture with brachial plexus block anaesthesia: a prospective, double-blind randomised clinical trial.

Rebound pain after brachial plexus block resolution and development of long-lasting pain are problems associated with volar plate fixation for distal radius fractures. The aim of this double-blind study was to evaluate the effect of a single prophylactic intravenous dose of dexamethasone in this setting. The primary endpoint was highest pain score during the first 24 hours after surgery. We included 51 adults of ASA physical status 1-2 due to undergo planned acute fixation of the radius. All received premedication with oral paracetamol and etoricoxib, and a pre-operative brachial plexus block with ropivacaine. Patients were randomly allocated into two groups: a dexamethasone group receiving 16 mg dexamethasone intravenously at start of surgery and a control group receiving 4 ml saline. After surgery, all patients received fixed doses of paracetamol, etoricoxib and oxycodone, with further oxycodone added as needed in the first 48 hours. Pain, analgesic consumption and daily function were registered at predefined times up to 1 year after surgery. Median (IQR [range]) worst pain score in the first 24 hours, as assessed by verbal numeric rating scale (0-10), was 4 (2-6 [0-7]) in the dexamethasone group compared with 8 (5-8 [2-10]) in the placebo group (p < 0.001). Average pain score, 2 (1-4 [0-5]) vs. 5 (3-6 [0-8]), p = 0.001 and rescue oxycodone consumption, 5 (0-10 [0-35]) mg vs. 10 (5-15 [0-50]) mg, p = 0.037), respectively, were both significantly lower in the dexamethasone group compared with control from 8 to 24 hours. Brachial plexus block duration was 69% longer in the dexamethasone group, 21.5 (19.1-23.4 [12.9-24.1]) hours vs. 12.7 (11.9-15.3 [7.4-26.6]) hours, p < 0.001. Two patients (9%) in the dexamethasone group compared with 12 (50%) in the placebo group experienced worst pain scores of 8-10 during the first 36 hours (p = 0.002). At 3 and 7 days postoperatively, there were no significant differences between groups for pain scores or opioid consumption. At 6 months, 27 patients (57%) reported pain at the site of surgery, with significantly higher average pain score (p = 0.024) in the placebo group. At 1 year, two patients in the dexamethasone group reported pain compared with 10 in the placebo group (p = 0.015), and worst pain score was significantly higher in the placebo group (p = 0.018). We conclude that intravenous dexamethasone improves early postoperative analgesia and may also improve clinical outcomes after 6 and 12 months.

Cytostatic effects of radiographic contrast media in synchronized cell cultures.

The cytostatic effects of conventional high osmolal ionic contrast media (meglumine-calcium metrizoate and Na-metrizoate) and new low osmolal nonionic contrast media (iohexol and iopamidol) in synchronized cell cultures were tested. The cell-cycle prolongation was most pronounced when the contrast media were added in the G1 phase, but there was also a marked effect when the contrast media were added in the S phase or late in the G2 phase. The cytostatic effect even persisted into the first cell cycle following the termination of the exposure. All four contrast media exerted effects stronger than that of equiosmolal saline. Iohexol and iopamidol produced a more severe effect than meglumine-calcium metrizoate and Nametrizoate at equal osmolality. Thus, the cytostatic effect of contrast media cannot be explained only by hypertonicity; the contrast media must have an additional specific cytostatic effect. When the cytostatic effect was related to iodine concentration, the new low osmolal nonionic contrast media influenced the cell cycle less than the conventional high osmolal ionic contrast media.

Effects of radiographic contrast media on monolayer cell cultures.

The relationship between iodine concentration, osmolality, and toxicity for nine different contrast media was studied. High osmolal conventional ionic contrast media (Na-metrizoate, Na-iothalamate, meglumine/Na-diatrizoate, meglumine-calcium-metrizoate) and the new low osmolal nonionic (Metrizamide, iopamidol, iohexol) and ionic dimer (Meglumine/Na-ioxaglate) contrast media were tested. Monolayer cell cultures of human cervical carcinoma in situ cells were used as a test system. The toxicity of contrast media on cell cultures was strongly dependent on the osmolality, and different contrast media with the same osmolality had about similar effects on the cell cultures. However, contrast media seem to have some additional and more specific effects since equiosmolal saline and mannitol were better tolerated. When the toxicity was related solely to iodine concentration it emerged that the new low osmolal contrast media were much better tolerated than the high osmolal conventional contrast media.

Short-term effects of radiographic contrast media on monolayer cell cultures and hepatocytes.

Short-term effects of nine different contrast media, saline, sucrose, and mannitol on monolayer cell cultures and isolated rat hepatocytes were studied. Conventional high osmolal ionic contrast media (Na-metrizoate, Na-iothalamate, meglumine/Na-diatrizoate, meglumine-calcium-metrizoate) and the new, low-osmolal, nonionic (metrizamide, iopamidol, iohexol) and ionic dimer (meglumine/Na-ioxaglate) were tested. Dilutions of different contrast media at the same final osmolality produced similar effects on cultured cells and on isolated hepatocytes as assessed by the leakage of cytoplasmic lactate-dehydrogenase. This short-term toxicity seemed to be a function of the osmolality and of the exposure time. The effect of saline, sucrose, and mannitol was equal to that of contrast media at the same osmolality.

Incorporation of contrast media in cultured cells.

Monolayer cultures of human prostatic (PC-3) and cervical (NHIK 3025) carcinoma cells were grown on formvar film and exposed to moderate concentrations of contrast agents for 30 minutes to 4 hours. After the exposure period, the monolayers were quickly frozen, and cryosections were examined by electron microscopy and X-ray microanalysis. Iodine was not detected in control cells, but was found in the cells that had been exposed to iodine-containing contrast media. The amount of intracellular iodine increased with increasing exposure dose and time. Because the cells mostly presented no sign of membrane damage, our findings support the view that contrast media have the ability to enter intact cells.

Bone density and geometry after locked intramedullary nailing. Computed tomography of 8 femoral fractures.

8 patients with femoral shaft fracture treated with locked intramedullary (IM) nailing were examined by computed tomography (CT) a few days after nail removal. Cortical bone density, cortical thickness and geometrical shape of the fracture region were compared to those of the contralateral side. The cortical density was reduced by 23 percent at the mid-fracture level. However, at the same level the cortical thickness had increased by 47 percent, and the antero-posterior and medio-lateral diameters by 30 and 45 percent, respectively. We conclude that the fracture region of the femoral shaft had regained its mechanical properties at the time of nail removal.

In vivo thrombogenicity of intravascular ultrasound imaging catheters.

This study evaluates the frequency and significance of thrombus formation on the surface of intravascular ultrasound (US) imaging catheters. The investigation includes 63 consecutive patients who underwent 32 arterial and 38 venous intravascular procedures. At the end of the imaging procedure the US findings were observed during withdrawal of the catheter into the introducer sheath. Thrombus formation was demonstrated in 5 (7%). The largest thrombus fragments had a cross-sectional dimension of 2.2 x 1.0 mm. There was a significant correlation between the incidence of thrombus formation and the occurrence of malign neoplastic disease. No relation was found between the frequency of thrombus formation and the duration of the imaging procedure or the type of US catheter. It is concluded that the thrombogenicity of intravascular US imaging devices is not higher than that of conventional angiographic catheters. The observed "pull-out" thrombi were small and it is unlikely that they could have any clinical significance.

The extent of stress-protection after plate osteosynthesis in the human tibia.

The extent of stress-protection was investigated in 12 patients with previous tibial fractures treated by steel plate fixation. They were examined by computed tomography (CT) scanning one or two days after plate removal. The cortical density and thickness were determined by the CT scans. In the previously plated segment, a significant reduction in cortical density was found, and the reduction was most pronounced in the quadrant directly beneath the plate. The osteopenia did not increase with increasing duration of plate application in excess of one year. No significant differences in cortical thickness between plated and control tibiae occurred. The results indicate that stress-shielding after rigid plating in the human tibia is less pronounced than that previously reported from experimental studies in animals.

Bone atrophy after plate fixation. Computed tomography of femoral shaft fractures.

Twelve patients with previous femoral shaft fracture treated by rigid plate fixation were examined by computed tomography (CT) scanning 1 or 2 days after plate removal. In the previously plated segment an average reduction in cortical density of 11 per cent was found, and the reduction was most pronounced in the cortex directly beneath the plate. No reduction in cortical thickness of the plated bone occurred. Proximal and distal to the site of the plate, and in the ipsilateral tibial shaft, a slight reduction in cortical density and thickness averaging 2-3 per cent was found.

Bone loss after locked intramedullary nailing. Computed tomography of the femur and tibia in 10 cases.

10 patients with previous femoral shaft fracture treated with locked intramedullary nailing were examined by computed tomography (CT) a few days after nail removal. The bone density, cortical thickness and geometric shape of the fractured extremity were compared with those on the contralateral side. Only a small reduction in cortical density and thickness (4 and 7 percent, respectively) was revealed outside the fracture area in the diaphyseal part of the nailed bones. A distinct reduction in trabecular density was observed in the femoral condyles as well as in the ipsilateral tibial condyle (19 and 17 percent, respectively). Our results indicate that the stress-reducing effect of intramedullary nails on the femoral diaphysis is small.

Intravascular ultrasonography. Normal and pathologic findings in the great veins.

The intravascular ultrasonographic findings in normal and diseased veins after transfemoral catheterization of 25 patients are presented. The iliac veins, the inferior and superior vena cava, the renal veins, the right atrium, both brachiocephalic veins, and the right internal jugular vein were studied. In 4 cases valves or valve-like structures were observed. Anatomic variants such as spurs and webs were seen in 3 and mural thrombi or postthrombotic wall changes in 4 patients. In one case a sphincter-like ostium venae cavae was observed. In 2 patients thin filaments within the right atrium, most likely a Chiari net, were seen. Two patients had an abnormal, stratified "artery-like" vessel wall structure. This new imaging modality has several potential applicabilities in the veins and may contribute new information about anatomy and function of the venous system. It provides cross-sectional in vivo visualization and the demonstration of motility of small intraluminal structures which cannot be revealed by traditional diagnostic methods. Because of the wide range of anatomic variation in the venous system, knowledge of its normal intravascular ultrasonographic appearance is a prerequisite for further clinical investigations.

MRI of cerebrum and cervical columna within two days after whiplash neck sprain injury.

The present study was undertaken to evaluate if MRI within 2 days of a motor vehicle accident could reveal pathology of importance for understanding long-term disability after whiplash neck-sprain injuries. As part of a prospective study cervical and cerebral MRI was performed on 40 neck sprain patients with whiplash injury after car accidents. The imaging was done within 2 days of the injury to make sure that any neck muscle bleeding, oedema or other soft tissue injuries could be detected. The MRI findings from the patients were both correlated to reported symptoms 6 months after the accident and compared to a control group of 20 volunteers. The MRI of both brain and neck revealed no significant differences between the patients and the control group. When the patients were grouped according to the main MRI findings at intake and compared according to the development of subjective symptoms reported by the patients, the only significant difference was more headaches at 6 months in the groups with disk pathology or spondylosis when compared to the group with no pathology. In conclusion, MRI within 2 days of the whiplash neck-sprain injury could not detect pathology connected to the injury nor predict symptom development and outcome.

Effects on the ATP content of cultured cells after radiographic contrast media exposure. Evidence for accumulation of contrast media in cultured cells.

The ATP content of cultured cells after exposure to meglumine-calcium metrizoate, sodium metrizoate, iohexol, iopamidol and saline was studied. Initially, the ATP content diminished rapidly for a short period and thereafter slowly during the incubation. After incubation with contrast media or saline, the ATP content slowly increased to normal when the cells were reincubated with fresh nutrient medium. Different contrast media and saline with the same final osmolality produced a similar effect on the ATP content of the cultured cells. Cellular association of meglumine-sodium diatrizoate, sodium metrizoate, sodium-iothalamate, iohexol and iopamidol was also examined. The established cell line NHIK 3025 as well as primary cultures of human umbilical endothelium were found to accumulate contrast media in a time- and concentration-dependent manner. When the incubation was carried out at 4 degrees C, the cellular accumulation of contrast medium was less than 35 per cent of that seen at 37 degrees C. It therefore seems that energy-dependent processes are involved to some degree.

Intracellular penetration and accumulation of radiographic contrast media in the rat kidney.

Radiographic iodine-containing contrast media (meglumine calcium metrizoate, iohexol and meglumine sodium ioxaglate) were injected intravenously in rats. At various intervals after exposure, in situ cryofixation of kidneys was performed. Thin, freeze-dried cryosections were examined by electron microscopy and X-ray microanalysis. In endothelial cells, erythrocytes and tubular cells high dry weight concentrations of iodine were found. Twenty-four hours after iohexol was injected, no trace of iodine was found in the plasma, microvilli or the nuclei of the tubular cells. Small organelle-like compartments in the cytoplasm of the proximal tubular cells contained high concentrations of iodine, whereas no iodine was found in the surrounding cytoplasm. Since no metabolism of contrast medium has been demonstrated, the iodine signals must be emitted from contrast medium molecules. Other elements were also measured, with the concentrations being always within the ranges found in tubular cells of control animals. The detection of intracellular contrast thus does not seem to be an artifact due to cell injury, but rather represents a physiological event in healthy cells in the rat kidney. Our results are in contradiction to the prevailing opinion that contrast media do not enter healthy cells. However, previous conclusions have been based on the use of conventional preparation methods, and the highly water soluble contrast molecules may have been lost during the different steps of fixation and processing.

[How is the specialist training in radiology?]. / Hvordan er det å vaere utdanningskandidat i radiologi?

BACKGROUND: On the basis of results from a focus group interview showing that the specialist training in radiology was considered unsatisfactory, we performed a questionnaire survey among residents attending specialist training in Norwegian x-ray departments. MATERIAL AND METHODS: A questionnaire on background and working and study conditions was mailed to 113 radiology residents. RESULTS: The response rate was 73%. More than 50% of the residents reported that the quality of the training they received in magnetic resonance imaging and to some extent in interventional radiology and doppler examinations, was unsatisfactory, independent of type of department. Residents working in larger departments reported more problems in learning the most common interventional procedures, CT examinations and fluoroscopy examinations than did collegues working in smaller departments. Experienced autonomy with regard to organisation of own work was significantly lower among female physicians than among their male collegues. INTERPRETATION: There is shortage of time as well as specific learning possibilities for Norwegian radiology residents. The potential for improvement is large.

MR imaging and radiography of patients with cervical hyperextension-flexion injuries after car accidents.

Fifty-two patients underwent MR imaging and conventional radiography of the neck within 4 days after a hyperextension-flexion injury. The patients also had follow-up investigations during the first 2 years. The images did not reveal any serious lesions in any of them. Based on the main MR and radiographical findings the patients were divided into 4 groups; no findings, posture abnormalities, spondylosis and disc pathology (from MR images) or reduced intervertebral space (from the radiographs). The outcomes of the different groups were compared with reference to neck stiffness, neck pain and headache during a 2-year follow-up period. The patient groups did not correspond completely when diagnosed from MR imaging and radiography. However, patients with pre-existing spondylosis had more symptoms when examined by both modalities. Based on the radiographs, the group with posture abnormalities had significant fewer symptoms than the other groups.

[Endovascular treatment of abdominal aortic aneurysms]. / Endovaskulaer behandling av abdominale aortaaneurismer.

Eight patients, six men and two women (mean age 67.3 years) were treated for infrarenal abdominal aortic aneurysm by endovascular technique. A bifurcated graft (Mialhe Stentor, Min Tec, France) was used in all cases. The introducing system, with an 18 French diameter, is inserted through an arteriotomy in the common femoral artery. The proximal end of the main part of the graft is placed just distal to the renal arteries, and includes one graft limb, which is placed in the iliac artery on the ipsilateral side. The contralateral graft limb is introduced into a short limb of the main graft through a 10 French introducer, using Seldinger-technique, from the contralateral common femoral artery. All the implantations were successful from both a technical and a clinical point of view. All patients except one were mobilized on the first day after operation and received a normal diet. A thorough preoperative evaluation of the patient with regard to selection of the right size of the implant is necessary, and the implantation must be performed with great attention to technical details.

Intravascular ultrasonographic assessment of thrombus formation on central venous catheters.

In vitro experiments were performed in order to investigate the appearance of different types of central venous catheters at intravascular ultrasonography. The experiments were repeated with artificially produced thrombi which were made adherent to the catheter wall. All thrombi larger than 1 mm could be identified. In a clinical study including 12 patients who had a central venous catheter, transfemoral intravascular ultrasonography was performed. The catheters had been in place for an average period of 54 days (range 1-360 days). In 3 patients a catheter thrombus, mural thrombus, or occlusive vein thrombosis was found. In 2 of these patients the catheter was occluded, in the 3rd patient it was malpositioned into the contralateral brachiocephalic vein. There were no complications following the ultrasonographic procedures. Mean catheterization time was 7.5 min (range 3-20 min). The advantages of this new method compared with conventional phlebographic studies and its impact on further clinical investigations are discussed.

Intravenous ibandronate injections given every three months: a new treatment option to prevent bone loss in postmenopausal women.

OBJECTIVE: To investigate the efficacy, safety, and dose response of three doses of ibandronate, given intermittently by intravenous (IV) injection every three months, in preventing postmenopausal osteoporosis. PATIENTS AND METHODS: 629 postmenopausal women, categorised according to time since menopause and baseline lumbar spine (L1-4) bone mineral density (BMD), were enrolled into a multicentre, double blind, placebo controlled trial. They were randomly allocated to receive IV ibandronate 0.5 mg, 1 mg or 2 mg, or placebo every three months. All women received daily calcium supplementation. RESULTS: One year's treatment with intermittent IV ibandronate injections produced a dose dependent gain in mean (SD) lumbar spine BMD from baseline of 2.5 (2.5)%, 1.8 (2.6)%, and 1.0 (2.8)% in the groups receiving 2 mg, 1 mg, and 0.5 mg ibandronate, respectively, compared with a loss of BMD of 0.4 (2.4)% in the women in the placebo group; p=0.0001 for each ibandronate dose v placebo. Highest BMD gains occurred in women with osteopenia receiving 2 mg ibandronate. Similarly, at the hip, all three doses of ibandronate produced significantly better gains in BMD than placebo (p<0.05), with the greatest gains in the women with osteopenia receiving the 2 mg dose. Ibandronate concomitantly and dose dependently suppressed markers of bone turnover in comparison with placebo, and injections were well tolerated. CONCLUSION: IV ibandronate injections, given every three months, may be an effective alternative to oral bisphosphonates and hormonal therapy in the prevention of bone loss in postmenopausal women.

Intravascular ultrasonographic appearance of angiographically normal arteries related to age and the occurrence of vascular disease.

In 22 individuals (mean age 52 years) the ultrasonographic images of arteries defined as normal by arteriography were studied and related to the age and medical history of the patients. The series was divided into 2 groups: patients with clinical manifestation of atherosclerosis and patients without a history of arterial disease. The study included 6 young patients (mean age 14 years) referred for angiographic documentation of abolished intracranial circulation. A typical 3-layered appearance of the arterial wall was found in young healthy individuals as well as in adult and elderly subjects. There was no difference in the ultrasonographic appearance of muscular and elastic arteries. In patients with extensive obstructive atherosclerosis affecting other parts of the arterial tree, a segment of the iliac artery can have the same appearance as seen in young healthy individuals. There are indications that severe hypertension can result in a thickening of the middle low-echogenic layer of the arterial wall. In patients with chronic renal insufficiency, small calcifications in the middle layer were a typical finding.