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We report two cases of aneurysm of an aberrant right subclavian artery. Imaging findings, diagnostic criteria and evolution patterns of this rare condition are reviewed. CT seems to be the best imaging modality to assess these aneurysms. To avoid rupture, growing aneurysms should be surgically removed whenever it is technically feasible.
Surgery is the only curative treatment of renal cell carcinoma (RCC). Preoperative staging is aimed at evaluating surgical possibilities and optimal surgical technique. Thoracic and abdominal CT is the best way to routinely evaluate locoregional and metastatic extension of the tumor. However, there is no consensus concerning which laboratory and imaging studies should be obtained to assess patients after radical nephrectomy or conservative surgery. Objectives of this review
OBJECTIVES: Efficacy evaluation of high intensity focused ultrasound (HIFU) treatment for localized prostate cancer and identification of the factors affecting the outcome. PATIENTS AND METHODS: 102 patients with prostate cancer stage T1-T2 and noncandidates for radical prostatectomy have been treated with HIFU (Ablatherm, EDAP-Technomed). The disease progression (failure) was strictly defined by any positive sample at control biopsies, whatever the prostate-specific antigen (PSA) level, or by 3 consecutive increases in PSA levels in case of negative biopsies. RESULTS: At inclusion, patients' baseline characteristics were (mean +/- standard deviation): age 70.8 (+/-6.13) years, PSA 8.38 (+/-4.8) ng/ml, prostate volume 33.3 (+/-16.71) cm3. The population mean follow-up was 19 months (3-76 months). The overall success rate was 66%. Statistically significant variations of the overall success with a more favorable outcome were observed when (1) the initial PSA level was < or =10 ng/ml (73 vs. 50%, p = 0.02), (2) the Gleason score was < or =6 (81 vs. 46%, p<0.001) and (3) the pretreatment sextant biopsy evidenced 1-4 positive samples (68 vs. 40%, p = 0.01). CONCLUSION: Results observed after HIFU treatment in localized prostate cancer are now challenging those obtained after radiation therapy. The success rate is influenced by disease-related prognostic factors.
OBJECTIVES: To evaluate the accuracy of gadolinium-enhanced MRI in gauging the extent of the tissue damage induced by transrectal high intensity focused ultrasound (HIFU) therapy and to assess how well the results obtained with this modality correlate with histological findings (control biopsies). METHODS: Twenty-one patients with biopsy-proven prostate cancer (T1-T2-T3a, Nx, M0) who gave informed consent were included in the protocol. They underwent pre- and postoperative (2-5 days after HIFU treatment) MR examinations. Fifteen patients also underwent a follow-up MR examination 1-5 months postoperatively. MR findings were compared with the results of postoperative transrectal biopsy examinations. RESULTS: The prostate volume increased after the HIFU session from 43.9+/-18.6 to 52.1+/-21 cm(3) by day 2 (p<0.001). On fat-saturated gadolinium-enhanced T1-weighted images, the treated area appeared as a hypointense zone surrounded by a peripheral rim of enhancement in all patients. A positive correlation (r = 0.75) was found between the volume of the hypointense zone measured at days 2-5 (30+/-11 cm(3), 67% of the posttreatment prostate volume) and the theoretical target volume (22+/-5 cm(3), 61% of the initial prostate volume). MRI showed that the anterior part of the base was not reached by the ultrasound beam. The mean volume of the untreated zone (prostate without any MRI modifications) was 8 cm(3) (range, 0.4-36). No correlation was found between the MRI appearance of the treated area and the intensity of the necrosis or the presence of foci of residual, viable cancer. CONCLUSION: Gadolinium-enhanced MRI is an accurate way of determining the extent of tissue damage induced in HIFU ablative therapy, but cannot predict histological results.
UNLABELLED: The localisation of aldosterone-producing adenomas (APA's) remains difficult. Indeed, CT scan may not detect small APA's while CT detected tumours do not necessarily produce aldosterone. OBJECTIVE: To evaluate the value of adrenal vein catheterization (AVC) for the diagnosis of APA's and also the rates of unsuccessful procedures and complications. PATIENTS: One-hundred-and-nine hypertensives with biological features of primary hyperaldosteronism were included. Plasma sodium, potassium, aldosterone and renin levels were obtained after one night in lying position. Aldosterone and renin levels were also measured after a one-hour walking period and after a sodium expansion with saline. All patients underwent a CT scan and AVC. For adrenal samples, the ratio of aldosterone to cortisol concentrations was calculated for both sides. Both ratios were divided by the opposite one and the higher was retained as an index of laterization (IL). For lack of a golden standard variable, we have taken as a working hypothesis that operated patients had an APA (n = 38) and the non operated ones bilateral hypereplasia (n = 71). RESULTS: Operated patients had a shorter history of hypertension, more frequently a left ventricular hypertrophy on ECG, and lower serum creatinine and potassium levels, along with a higher sodium level. None of these features appeared discriminant, however. Presence of a 10-mm tumour on CT scan was not significantly different between the 2 groups. Operated patients had more than a five-fold higher IL compared with that of non-operated patients. Analysis using a ROC curve showed that the value of 12 for "IL" was an acceptable operational criterium of lateralization, producing a specificity of 90%, while maintaining a sensitivity of 62%. AVC appeared most useful in case of middle-range pre-test probability of an APA being present, that is when when clinical, biological, or radiological features are not fully concordant. The rate of unsuccessful procedure and the rate of complications were low (1.8% and 3.6%, respectively). CONCLUSION: With a low iatrogenicity, AVC appears helpful in indicating surgery mostly when clinical, biological, and CT scan features are not fully concordant. A value of 12 for IL appears to allow a high specificity while retaining an acceptable sensitivity.
PURPOSE: To evaluate the effects of contrast media pharmokinetic differences on aortic enhancement at abdominal CT angiography and to determine whether these effects are of clinical relevance. MATERIAL AND METHODS: Two hundred and twelve patients referred for abdominal CT angiography were included in the study. All abdominal CT angiograms were performed with the same parameters (collimation 3 mm, pitch ratio 1.7, scan delay 30 s) after i.v. injection of 120 ml of contrast medium at 3 ml/s. After randomization, patients received either iobitridol 300 (low-osmolar, 300 mg I/ml), iobitridol 350 (low-osmolar, 350 mg I/ml) or ioxithalamate 350 (high-osmolar, 350 mg I/ml). The time attenuation curves obtained with the three contrast media were compared. RESULTS: The time attenuation curve obtained with ioxithalamate 350 was not parallel to those obtained with iobitridol 300 and iobitridol 350. Mean peak enhancements obtained with iobitridol 350 and ioxithalamate 350 were not significantly different but iobitridol 350 provided higher mean peak enhancement than iobitridol 300. Mean delays of the peak enhancements were the same with the three contrast media. After peak enhancement, the decrease of aortic opacification under a selected threshold of 200 HU was significantly slower with iobitridol 350 than with iobitridol 300 and ioxithalamate 350, whereas iobitridol 300 and ioxithalamate 350 showed no significant differences. CONCLUSION: For a given iodine concentration, low-osmolality contrast media provide longer aortic opacification and may be recommended for CT angiography when long acquisition times are needed.
BACKGROUND AND PURPOSE: Criteria for determining the durability of the response to transrectal high-intensity focused ultrasound (HIFU) ablation of prostate cancer have been established by calculating progression-free probability. PATIENTS AND METHODS: A series of 82 patients (mean age 71 +/- 5.7 years) with biopsy-proven localized (stage T1-T2) cancer who were not suitable candidates for radical surgery underwent transfectal HIFU ablation with the Ablatherm machine. The mean follow-up was 17.6 months (range 3-68 months). The mean serum prostate specific antigen (PSA) value and mean prostate volume were 8.11 +/- 4.64 ng/mL and 34.9 +/- 17.4 cm3, respectively. Progression was rigidly defined as any positive biopsy result, regardless of PSA concentration, or three successive PSA increases for patients with a negative biopsy (PSA velocity > or = 0.75). Times to specific events (positive biopsy and PSA elevation) were analyzed with the Kaplan-Meier survival method. RESULTS: Overall, 62% of the patients exhibited no evidence of disease progression 60 months after transrectal HIFU ablation. In particular, the disease-free rate was 68% for the moderate-risk group of 50 patients (PSA < 15.0 ng/mL, Gleason sum < 8, prostate volume < 40 cm3, and number of positive biopsies < 5). For the low-risk group of 32 patients (PSA < 10 ng/mL and Gleason sum < 7), the disease-free survival rate was 83%. CONCLUSION: Transrectal HIFU prostate ablation is an effective therapeutic alternative for patients with localized prostatic adenocarcinoma.
From 1984 to 1998, 808 patients underwent percutaneous nephrolithotomy for removal of renal calculi. Although the technique is safe and effective, complications, including hemorrhages, have been reported. Eight patients (1%) are described in whom severe bleeding following percutaneous nephrolithotomy was uncontrolled by usual methods and treated by hyperselective embolization. Renal arteriography has shown arteriovenous fistula in 3 patients, pseudo aneurysm in 4 and both in1 patient. Embolization allowed definitive treatment of these lesions in 7 of our 8 patients. The failure of embolization in 1 patient imposed a partial nephrectomy. Patients with normal renal function did not suffer significant change in the serum creatinine after treatment (percutaneous nephrolithotomy + embolization), and all but 1 patient have maintained normal blood pressure. In the authors' opinion, hyperselective embolization is the least invasive and best treatment for massive hemorrhage after percutaneous nephrolithotomy.
Tubular ectasia of the rete testis (TERT) is a benign entity due to dilation of the tubules of the rete testis. Most of the time it is discovered incidentally on scrotal sonograms and may be misinterpreted as malignant. This article outlines the diagnostic criteria of TERT, its possible causes, its incidence and its potential evolution. Recognizing this entity owing to its characteristic clinical, sonographic and, if necessary, MRI features is important to avoid unnecessary surgery or biopsies.
PURPOSE: To evaluate helical computed tomography (CT) in the preoperative assessment of crossing arteries in kidneys with ureteropelvic junction (UPJ) obstruction and to compare the results with those obtained by means of angiography. MATERIALS AND METHODS: Forty-one consecutive patients with symptomatic UPJ obstruction in 42 obstructed kidneys underwent renal helical CT and renal intraarterial digital subtraction angiography (DSA; flush aortography and bilateral selective renal injections). The helical CT and DSA images were interpreted in a blinded manner by two readers, and the results were compared. RESULTS: DSA showed 126 renal arteries in the 41 patients; 56% of patients had supernumerary renal arteries. Helical CT depicted 121 (96%) of these 126 renal arteries prospectively. Retrospectively, 124 (98%) renal arteries were visible on CT images. Twelve (29%) of the 42 kidneys with UPJ obstruction had identifiable arteries crossing the UPJ on DSA images. If DSA is used as the standard of reference, CT angiography was 100% sensitive and 96.6% specific for depicting these crossing arteries. CONCLUSION: Renal helical CT seems suitable to replace intraarterial DSA in the preoperative assessment of crossing arteries in kidneys with UPJ obstruction.
OBJECTIVES: To demonstrate a correlation between abdominal computed tomography (CT) data and the histological stage of upper urinary tract tumour (UUTT) in order to more accurately define therapeutic indications. MATERIALS AND METHODS: From 1984 to 1995, 51 patients were treated for UUTT and were assessed by preoperative abdominal CT. 41 of the 51 CT scans were considered to be interpretable and were reviewed retrospectively by a single radiologist. The CT stage and tumour diameter were compared to the pathological stage. RESULTS: CT staging had a reliability of 76%, by combining stages Ta-T2, which could not be distinguished. The sensitivity of CT to assess invasion of the renal parenchyma and ureteric or perirenal fat was 100% and 70%, respectively, with a specificity of 82% and 97%. The accuracy can be improved by decreasing the thickness of sections of the tumour. Tumour diameters (d) of pyelocaliceal tumours, measured by CT and pathology, were closely correlated (r2 = 0.83). All UUTTs less than 3 cm in diameter were found to be superficial on histology. CT correctly estimated the size of these small tumours in 14/15 cases. Overall, by setting the limit at 3 cm, CT was able to detect a superficial pyelocaliceal tumour with a specificity of 92% and a PPV of 93%; however, a CT size > or = 3 cm is not predictive of the histological stage of the lesion. CONCLUSIONS: CT is still imprecise for the staging of UUTT, as it cannot distinguish between Ta, T1 and T2 lesions, and is still not sufficiently reliable in the assessment of invasion of the periurothelial fat or of the renal parenchyma. CT measurement of the diameter of pyelocaliceal tumours can provide an argument in favour of the superficial nature of the lesion and therefore guide the therapeutic decision towards a conservative approach.
Iobitridol was clinically tested in DSA against iopromide (i.v. DSA) or iohexol (i.a. DSA) in 139 patients. Seven patients participated in the i.v. DSA trial and 60 in the i.a. DSA study. Each examination was rated as diagnostic or not and the image quality was noted. Nature, onset, intensity and outcome of each adverse reaction were recorded. There was no significant difference in imaging quality and side effect occurrence between the 2 groups. We conclude that iobitridol is a safe and efficient contrast medium, which can be recommended for DSA examinations.
Iobitridol 250 (Xenetix 250) was compared with iohexol 240 (Omnipaque 240) in phlebography of the lower limbs by means of a multicenter, randomized double-blind trial in 70 patients. No significant difference was demonstrated between the 2 groups in terms of diagnostic efficacy, image quality or clinical safety. Only minor reactions were recorded in the 2 groups, essentially consisting of mild or moderate heat sensations. The only insufficiently informative examinations were not due to the contrast agent. Iobitridol 250 therefore appears to be a well-tolerated contrast medium, suitable for use in phlebography of the lower limbs.
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This work was undertaken to investigate whether the inhibitory tone exerted by GABA on somatostatin (SRIH) release operates in the control of thyrotropin (TSH) secretion in both basal and cold-stimulated conditions. In a first group of animals (G1) undergoing both carotid and third ventricle push-pull cannulation, i.vt. injection of picrotoxin (10(-5) M) induces a significant decrease in plasma TSH level under basal conditions (0.09 +/- 0.02 versus 0.27 +/- 0.4 ng/100 microliters; P < 0.03, n = 5). In a median eminence (ME) push-pull cannulated group of rats (G2), picrotoxin, peripherally administered, blocks cold-induced inhibition of SRIH release (35.0 +/- 1.8 versus 7.4 +/- 3.3 pg/15 min; P < 0.005; n = 5). In a third group of intact rats (G3), peripheral administration of picrotoxin (2 mg/kg i.p.) blunts the cold-induced TSH release (0.17 +/- 0.03 versus 0.46 +/- 0.04 ng/100 microliters; P < 0.001; n = 5). Our results strongly suggest that a decrease in SRIH release is involved in the GABAergic control of basal and cold-induced TSH secretion.
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