Catheter Angiography Findings Research Articles

How Do We Perform Imaging Tests before Treating Cerebral Aneurysms?

Acquiring appropriate preoperative images is an important step in the treatment of cerebral aneurysms. Despite recent advances in contrast-enhanced CT and MRI, catheter angiography remains the standard of care in preoperative imaging tests for both ruptured and unruptured intracranial aneurysms. Three-dimensional rotational angiography can provide a clear view of vascular structure around the aneurysm in an intuitive manner, including the small perforators. For ruptured aneurysms, the treatment modality(i.e., surgical clipping or endovascular embolization)is usually based on emergent contrast CT and catheter angiography findings. For unruptured aneurysms, integrated assessment involving CT, MRI, and angiography is often useful in multimodal treatment decision making.

Correlation of Aggressive Intracranial Lesions and Venous Reflux Patterns in Dural Arteriovenous Fistulas.

The association between venous reflux patterns with aggressive intracranial lesions (AILs), including intracranial edema (IE), intraparenphymal hemorrhage (IPH), and subarachnoid hemorrhage (SAH), has not been well established in cranial dural arteriovenous fistulas (DAVFs). We propose an updated classification system based on venous drainage. We retrospectively assessed the catheter angiography findings of venous drainage patterns. Cranial DAVFs with no reflux flow and those with reflux flow drainage into the sinus only, the bridge vein only, the bridge vein and pial vein, and the sinus, bridge vein, and pial vein were designated as types 1, 2, 3, 4, and 5, respectively. We analyzed the associations between venous reflux patterns with AILs in 73 patients with DAVFs. AILs were found in 43 patients (58.9%), including 8 (11%) with SAH, 8 (11%) with IPH, and 27 (36.9%) with IE. Our proposed classification scheme was significantly associated with AILs (P < 0.001). SAH was found in patients with type 3 (62.5%) and type 4 (37.5%), whereas IPH was seen mostly in those with type 4 (87.5%). The proportion of IE gradually increased from type 3 to type 5 (11.1% to 29.6% to 59.2%). Significant difference was found among each type between complete resolution and uncompleted resolution after endovascular treatment (P=0.034), which also demonstrated a gradually increasing proportion of uncompleted resolution from type 1 to type 5 (4.5%, 4.5%, 9.1%, 31.8%, and 50%). Our proposed classification system effectively demonstrates a correlation between venous reflux patterns and AILs and outcomes of endovascular treatment in patients with DAVFs.

Neuroradiologic characteristics of astroblastoma and systematic review of the literature: 2 new cases and 125 cases reported in 59 publications.

Astroblastoma is a rare tumor of uncertain origin most commonly presenting in the cerebrum of children and young adults. The literature contains only case reports and small series regarding its radiologic features. This systematic review is the largest study of imaging findings of astroblastoma to date and serves to identify features that might differentiate it from other neoplasms. This study describes the imaging features of astroblastoma based on a systematic review of the literature and two new cases. We conducted a PubMed and Google Scholar database search that identified 59 publications containing 125 cases of pathology-confirmed astroblastoma, and we also added two new cases from our own institution. Data collected include patient age, gender, tumor location, morphology, calcifications and calvarial changes. We recorded findings on CT, MRI, diffusion-weighted imaging (DWI), MR spectroscopy, positron emission tomography (PET) and catheter angiography. Age at diagnosis ranged 0-70years (mean 18years; median 14years). Female-to-male ratio was 8:1. Of 127 cases, 66 reported CT, 78 reported MRI and 47 reported both findings. Not all authors reported all features, but the tumor features reported included supratentorial in 96% (122/127), superficial in 72% (48/67), well-demarcated in 96% (79/82), mixed cystic-solid in 93% (79/85), and enhancing in 99% (78/79). On CT, 84% (26/31) of astroblastomas were hyperattenuated, 73% (27/37) had calcifications and 7 cases reported adjacent calvarial erosion. Astroblastomas were hypointense on T1-W in 58% (26/45) and on T2-W in 50% (23/46) of MRI sequences. Peritumoral edema was present in 80% (40/50) of cases but was typically described as slight. Six cases included DWI findings, with 100% showing restricted diffusion. On MR spectroscopy, 100% (5/5) showed nonspecific tumor spectra with elevated choline and decreased N-acetylaspartate (NAA). PET revealed nonspecific reduced uptake of [F-18] 2-fluoro-2-deoxyglucose ((18)F-FDG) and increased uptake of [11C]-Methionine in 100% (3/3) of cases. Catheter angiography findings (n=12) were variable, including hypervascularity in 67%, arteriovenous shunting in 33% and avascular areas in 25%. Astroblastomas occur most often in adolescent girls. Imaging often shows a supratentorial, superficial, well-defined, cystic-solid enhancing mass. On CT, most are hyperattenuated, have calcifications, and may remodel adjacent bone if superficial. MRI characteristically reveals a hypointense mass on T1-W and T2-W sequences with restricted diffusion. MR spectroscopy, PET and catheter angiography findings are nonspecific.

Assessment of arteriovenous malformations with 3-Tesla time-resolved, contrast-enhanced, three-dimensional magnetic resonance angiography

Although conventional catheter angiography is commonly used in the evaluation of intracranial arteriovenous malformations (AVMs), less invasive tools are more suitable for screening or follow-up. Older MR angiography techniques cannot provide high enough temporal and spatial resolution for assessing AVMs. Threetesla time-resolved imaging of contrast kinetics (TRICKS)-a time-resolved, contrast-enhanced 3D MR angiography technique-achieves subsecond time resolution without sacrificing spatial resolution. The purpose of this study was to assess the accuracy of TRICKS at 3 T in the evaluation of AVMs. Between November 2006 and November 2007, 31 patients who were known to have AVMs underwent evaluation in a 3-T unit with the TRICKS technique. The TRICKS images were then evaluated independently by 2 radiologists for nidus detection, early venous filling detection, and Spetzler-Martin classification, and these results were compared with the results of catheter angiography. Time-resolved imaging of contrast kinetics achieved 96% sensitivity and 100% specificity both in nidus detection and early venous filling detection. The Spetzler-Martin grades also showed excellent correlation with catheter angiography findings (kappa= 0.89). Although this is a preliminary study, the authors' results indicate that time-resolved contrast-enhanced 3D MR angiography at 3 T is a good tool to assess AVMs, and has the potential to replace catheter angiography in screening or follow-up examinations of patients with AVMs.

Excretion urogram with angiotomography sensitivity and specificity in the diagnosis of renal artery stenosis; a comparison with differences in renal size and contrast density on early films (author's transl)

Intravenous bolus injection of contrast material with angiotomography permits direct demonstration and evaluation of the renal arteries during an excretion urogram. Angiotomography was carried out in 71 patients with suspected reno-vascular hypertension; the results were compared with contrast excretion and renal size on the two sides, and with the findings of catheter angiography. In the presence of haemodynamically significant stenosis the sensitivity of angiotomography was 87% and its specificity was 99%. The sensitivity of renal size differential was only 20% and of contrast excretion differential 47%. A combination of all three methods resulted in a sensitivity of 93%. The advantages of demonstrating the renal arteries as a part of an excretion urogram are discussed, particularly with respect to possible treatment.