Skin and thyroid dosimetry in cervical spine screening: two methods for evaluation and a comparison between a helical CT and radiographic trauma series

OBJECTIVE: The first objective of this study was to test the hypothesis that estimates of radiation dose from an ionization chamber correspond to thermoluminescent dosimeter measurements in patients with suspected cervical spine injury. The second objective was to compare the radiation dose of a protocol using helical CT of the entire cervical spine with that of a protocol using radiography alone. SUBJECTS AND METHODS: Thermoluminescent dosimeter measurements of radiation dose to the skin over the thyroid were made in two patient groups: six patients evaluated with CT of the cervical spine and six patients evaluated with radiography. The skin dose for both groups was estimated with an ionization chamber, and the thermoluminescent dosimeter measurements and ionization chamber estimates of skin dose were compared for both groups. Using the ionization chamber, we estimated the radiation dose to the thyroid for all 12 patients. With these estimates, we computed the ratios of skin dose and thyroid dose (CT / radiography). RESULTS: Thermoluminescent dosimeter measurements correlated with ionization chamber estimates of skin dose in both patient groups. Using the ionization chamber estimates, we found that CT delivered 26.0 mGy to the thyroid. In the patients evaluated with radiography, the mean thyroid dose was 1.80 mGy (95% confidence interval, 1.05-2.55 mGy). Ionization chamber dose ratios (CT / radiography) for the skin and thyroid were 9.69 and 14.4 mGy, respectively. CONCLUSION: The correlation between the ionization chamber estimates and the thermoluminescent dosimeter measurements supports the use of ionization chamber estimates in future research. Although helical CT of the entire cervical spine is cost-effective in patients at high risk for fracture, the greater than 14-fold increase in the radiation dose to the thyroid emphasizes the importance of clinical stratification to identify patients at high risk for fracture and the judicious use of CT in patients with suspected cervical spine injury.     

Multi-detector row CT urography: comparison of strategies for depicting the normal urinary collecting system

PURPOSE: To evaluate several protocols for depiction of the urinary collecting system with multi-detector row computed tomographic (CT) urography. MATERIALS AND METHODS: Fifty-one patients with hematuria or a suspicious renal mass underwent CT urography, during which thinly collimated (1-mm) pyelographic phase scanning was performed 8-10 minutes after contrast medium administration. Patients were examined while prone only (n = 17) and while both prone and supine (n = 17) after a 250-mL infusion of normal saline. Each collecting system and ureter was divided into six segments that were assigned opacification scores. All acquisition techniques were compared, and the highest-scoring technique was compared with that in 17 patients who underwent conventional intravenous urography (IVU). Three reconstruction techniques (transverse, coronal, and maximal intensity projection) were also compared. Stratified analysis was performed with the paired two-tailed Student t test to compare opacification scores for both the acquisition techniques and display methods, both individually and in all possible combinations. RESULTS: CT urography with supplemental saline administration, performed with the patient prone or supine, significantly improved mean opacification scores in the distal ureters (right, P =.004; left, P =.006). With this technique, CT urography produced a mean opacification score that was not significantly different from that with IVU in 11 of 12 segments and was significantly better than that with IVU in one of 12 segments (lower left ureter). Mean opacification scores obtained with transverse or coronal displays were equal to or higher than those obtained with maximum intensity projection reconstructions in all segments. CONCLUSION: CT urography with a multi-detector row scanner and supplemental infusion of normal saline reliably displays the opacified urinary collecting system.     

Patient radiation dose at CT urography and conventional urography

PURPOSE: To measure and compare patient radiation dose from computed tomographic (CT) urography and conventional urography and to compare these doses with dose estimates determined from phantom measurements. MATERIALS AND METHODS: Patient skin doses were determined by placing a thermoluminescent dosimeter (TLD) strip (six TLD chips) on the abdomen of eight patients examined with CT urography and 11 patients examined with conventional urography. CT urography group consisted of two women and six men (mean age, 55.5 years), and conventional urography group consisted of six women and five men (mean age, 58.9 years). CT urography protocol included three volumetric acquisitions of the abdomen and pelvis. Conventional urography protocol consisted of acquisition of several images involving full nephrotomography and oblique projections. Mean and SD of measured patient doses were compared with corresponding calculated doses and with dose measured on a Lucite pelvic-torso phantom. Correlation coefficient (R(2)) was calculated to compare measured and calculated skin doses for conventional urography examination, and two-tailed P value significance test was used to evaluate variation in effective dose with patient size. Radiation risk was calculated from effective dose estimates. RESULTS: Mean patient skin doses for CT urography measured with TLD strips and calculated from phantom data (CT dose index) were 56.3 mGy +/- 11.5 and 54.6 mGy +/- 4.1, respectively. Mean patient skin doses for conventional urography measured with TLD strips and calculated as entrance skin dose were 151 mGy +/- 90 and 145 mGy +/- 76, respectively. Correlation coefficient between measured and calculated skin doses for conventional urography examinations was 0.95. Mean effective dose estimates for CT urography and conventional urography were 14.8 mSv +/- 90.0 and 9.7 mSv +/- 3.0, respectively. Mean effective doses estimated for the pelvic-torso phantom were 15.9 mSv (CT urography) and 7.8 mSv (conventional urography). CONCLUSION: Standard protocol for CT urography led to higher mean effective dose, approximately 1.5 times the radiation risk for conventional urography. Patient dose estimates should be taken into consideration when imaging protocols are established for CT urography.     

Fracture of the radial head: the role of excision

AIM: We assessed retrospectively forty cases of radial head fractures treated by excision. METHODS: The series is composed of men in 60% of cases and women in 40% of cases. The age of patients ranged from 15 to 68 years with an average of 37 years. According to Duparc classification, the fracture was type II in 20% of cases, type III in 32%, type IV in 42% and type V in 6%. An associated lesion in the same elbow was seen in 50% of cases; elbow dislocation was present in 38% of cases. The average of operative delay was 14 days (0 - 40 days). RESULTS: The functional result was evaluated according to clinical score of Western Orthopaedic society. The results were satisfactory. We have noted a correlation between functional result and associated lesions, the delay of excision and postoperative immobilisation. Valgus ulna and ascension of the radius was minors and well tolerated exceptly in cases of fractures associated to elbow dislocations. CONCLUSION: According to the results, we think that excision of radial head can be proposed essentially for the treatment of isolated radial head fracture.     

Pro-inflammatory cytokines and prostate-specific antigen in hyperplasia and human prostate cancer

Background: The aim of this study was to relate the expression, analyzed by Western blot and immunohistochemistry, of several pro-inflammatory cytokines, including IL-1, IL-6 and TNF-α, with serum levels of prostate-specific antigen (PSA) in normal and pathologic (hyperplasia and cancer) prostate tissues to elucidate their possible role in tumor progression. We are also discussing the possible use of these cytokines as a potential therapeutic target. Methods: The study was carried out in 5 normal, 25 benign prostatic hyperplastic (BPH) and 17 cancerous human prostates (PC). Immunohistochemical and Western blot analysis were performed. Serum levels of PSA were assayed by an immulite autoanalyzer. Results: The most relevant results showed that in BPH, IL-1α, IL-6 and tumor necrosis factor (TNF) were only expressed in patients with PSA serum levels of 0-4 or 4-20 ng/ml, but not in the group >20 ng/ml. In PC these cytokines were only expressed in patients with PSA serum levels >4 ng/ml. Conclusions: In PC there was an association between the high expression of pro-inflammatory cytokines (TNFα, IL-6, IL-1), elevated serum levels of PSA and cancer progression. A better understanding of the biologic mechanism of this association may provide new targets for therapy in these patients.     

The Profile of Prostate Epithelial Cytokines and its Impact on Sera Prostate Specific Antigen Levels

The aim of this study was determined the expression of pro inflammatory cytokines in prostate epithelial cells. Furthermore, we analysed the relation between these cytokines and sera PSA levels according the three groups: 0–4, 4–20 and >20 ng/mL. The study was carried out in five normal prostate (NP), 27 benign prostate hyperplastic (BPH) and 18 prostate cancer (PC). Immunohistochemical and Western blot analysis was performed. Serum levels of PSA were assayed by Immulite autoanalyser. The western Blotting analysis revealed an immunoexpression of IL-1α, IL-6 and TNFα in BPH and PC. IL-1α, was absent in NP. Immunohistochemical analysis showed significant high optical density to IL-1α and IL-6 in cancer epithelial cells (19.45 ± 3.25 and 26.2 ± 3.19) compared to normal cells (1.73 ± 1.51 and 4.83 ± 2.65). While, TNFα optical densities were not significant in NP (12.03 ± 2.9), BPH (9.87 ± 3.85) and PC (13.34 ± 2.34). The different profiles of cytokines according sera PSA levels showed a high immunoexpression of the profile (IL-6+, IL-1α+) in BPH patients with PSA between 0–4 and 4–20 ng/mL. However, PC patients with sera PSA between 4 and 20 ng/mL, showed a significant high immunoexpression of the profile (IL-6+, IL-1α−). This data demonstrate a locally production of pro-inflammatory cytokines by prostate epithelial cells and a cross talk between PSA and these cytokines in prostate pathologies.