Search

Treatment of pelvic arteriovenous malformations (AVMs) is frequently challenging because of the complex structures and anatomical diversity among cases. We present a case series of six patients with pelvic AVMs. All patients had a similar anatomical structure consisting of multiple feeders from the unilateral internal iliac artery, collecting into a dilated venous sac in the unilateral paravesical space and draining into a single outflow, eventually joining the pre-prostatic vein or internal iliac vein. Five among these patients were successfully treated by catheter-directed embolo-sclerotherapy. In addition to our six cases, we identified six previous case reports of pelvic AVM with similar anatomical characteristics. Herein, we summarize the clinical and anatomical features of these 12 paravesical AVM cases. In all cases, the patients were men; the AVM was predominantly located at the right paravesical space and demonstrated good therapeutic effect of catheter-directed embolosclerotherapy. These paravesical AVMs may constitute a new subgroup of pelvic vascular anomalies with the same etiology that are treatable by adequate catheter intervention.

The usefulness of carbon dioxide (CO2) gas digital subtraction angiography (DSA) has been reported for patients with renal insufficiency and allergy to iodinated contrast agents. However, CO2 gas cannot replace the iodinated contrast agent in all cases owing to some disadvantages. We describe balloon-occluded CO2 DSA (B-CO2 DSA) as an improved CO2 DSA procedure for interventions in the internal iliac artery (IIA) region and compare the quality of images obtained using conventional CO2 DSA and B-CO2 DSA. B-CO2 DSA-guided embolization was performed for one case of genital bleeding with an acute anaphylactic reaction to the iodinated contrast agent and for three cases of type II endoleaks after endovascular abdominal aortic aneurysm repair with renal dysfunction. A 9-mm occlusion balloon catheter was placed just after the orifice of the IIA. Then, 10–15 ml of CO2 gas was injected manually via the catheter with and without balloon occlusion. The quality of sequential digital subtraction angiograms was analyzed based on a scoring criterion. In all four cases, image quality was improved with B-CO2 DSA; the poor quality of images without balloon occlusion was because of reflux of the CO2 gas. B-CO2 DSA improves the image quality of CO2 DSA in the IIA region and is useful for vascular intervention. Level IV.

We evaluated the influence of catheter sampling position and size on left adrenal venous sampling (AVS) in patients with primary aldosteronism (PA) and analyzed their relationship to cortisol secretion. This retrospective study included 111 patients with a diagnosis of primary aldosteronism who underwent tetracosactide-stimulated AVS. Left AVS was obtained from two catheter positions - the central adrenal vein (CAV) and the common trunk. For common trunk sampling, 5-French catheters were used in 51 patients, and microcatheters were used in 60 patients. Autonomous cortisol secretion was evaluated with a low-dose dexamethasone suppression test in 87 patients. The adrenal/inferior vena cava cortisol concentration ratio [selectivity index (SI)] was significantly lower in samples from the left common trunk than those of the left CAV and right adrenal veins, but this difference was reduced when a microcatheter was used for common trunk sampling. Sample dilution in the common trunk of the left adrenal vein can be decreased by limiting sampling speed with the use of a microcatheter. Meanwhile, there was no significant difference in SI between the left CAV and right adrenal veins. Laterality, determined according to aldosterone/cortisol ratio (A/C ratio) based criteria, showed good reproducibility regardless of sampling position, unlike the absolute aldosterone value based criteria. However, in 11 cases with autonomous cortisol co-secretion, the cortisol hypersecreting side tended to be underestimated when using A/C ratio based criteria. Left CAV sampling enables symmetrical sampling, and may be essential when using absolute aldosterone value based criteria in cases where symmetrical cortisol secretion is uncertain.

PURPOSE We prospectively assessed whether enhancement characteristics on dynamic magnetic resonance (MR) imaging could distinguish indeterminate pulmonary nodules. METHODS We evaluated 51 pulmonary nodules in 51 consecutive patients (11 female, 40 male; mean age, 64 years) using dynamic MR images acquired at 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 120, 150, 180, 210, 240, 360, 480, 600, 720, and 840 s following injection of contrast material. We prospectively evaluated morphologic enhancement patterns, peak rate, time to peak enhancement, steepest slope, and washout of nodules and analyzed statistics to determine any differences between MR parameters, patient age, tumor size, and final diagnosis. RESULTS We found 25 malignant, 12 active inflammatory, and 14 benign nodules. Nodule diameter was significantly larger for malignant than nonmalignant, and benign nodules (P≤0.01). Patients with malignant nodules were significantly older than those with nonmalignant (P=0.01) and active inflammatory (P=0.02) nodules. However, morphologic enhancement patterns, peak rate, time to peak enhancement, steepest slope, and washout characteristics at 2, 4, 8, and 12 min showed no significant difference between malignant and nonmalignant nodules and among malignant, active inflammatory, and benign nodules. CONCLUSION Prospective assessment of dynamic MR images demonstrated their inadequacy for distinguishing indeterminate pulmonary nodules.