Editor’s Choices
A Prospective Trial of 3T and 1.5T Time-of-Flight and Contrast-Enhanced MR Angiography in the Follow-up of Coiled Intracranial Aneurysms • T.J. Kaufmann, J. Huston III, H.J. Cloft, J. Mandrekar, L. Gray, M.A. Bernstein, J.L. Atkinson, and D.F. Kallmes
Other past articles have dealt with comparisons between DSA and contrast enhanced MRA for detection of residual post treatment aneurysms. This article deals with a similar topic but addresses the question of which is better for MRA in this situation: 1.5T or 3.0T? The authors prospectively studied 63 coiled aneurysms within one week of obtaining DSA in them all. The non-invasive imaging included TOF MRA and CE-MRA at 1.5T and 3.0T (4 studies per patient). Regardless of the type of aneurysm remnant the sensitivity of MRA varied between 85-90%. However, CE-MRA was better for aneurysms with larger remnants. The authors concluded that both TOF and CE MRA should be obtained for the follow-up of post-coiled aneurysms.
Comparison of the Added Value of Contrast-Enhanced 3D Fluid-Attenuated Inversion Recovery and Magnetization-Prepared Rapid Acquisition of Gradient Echo Sequences in Relation to Conventional Postcontrast T1-Weighted Images for the Evaluation of Leptomeningeal Diseases at 3T • H. Fukuoka, T. Hirai, T. Okuda, Y. Shigematsu, A. Sasao, E. Kimura, T. Hirano, S. Yano, R. Murakami, and Y. Yamashita
Are there better sequences to use after Gd administration other than just the conventional T1-weighted images? Here the investigators compared post Gd 3D FLAIR and MPRAGE with T1WI. 12 patients with known leptomeningeal disease underwent all 3 sequences, which were thereafter subjectively evaluated. Also, the in vitro effect of different Gd concentrations on the FLAIR images was assessed. Results: in vivo and in vitro post Gd FLAIR images were better than MPRAGE or T1W ones.
Recanalization Rates Decrease with Increasing Thrombectomy Attempts • Y. Loh, R. Jahan, D.L. McArthur, Z.-S. Shi, N.R. Gonzalez, G.R. Duckwiler, P.M. Vespa, S. Starkman, J.L. Saver, S. Tateshima, D.S. Liebeskind, and F. Viñuela
If one uses the MERCI system to retrieve a clot, what is the optimum number of times one should try and after how many attempts does the possibility of success decline? To answer these questions the authors looked at 115 arterial occlusions (including ICA, MCA and vertebrobasilar ones). The average number of attempts was 3, and they also concluded that 3 is the optimum number of attempts. After 4 attempts the results more often included failed recanalizations and procedural complications.
Fellows’ Journal club
Adult Lumbar Scoliosis: Underreported on Lumbar MR Scans • Z. Anwar, E. Zan, S.K. Gujar, D.M. Sciubba, L.H. Riley III, Z.L. Gokaslan, and D.M. Yousem
It seems to me that all of us report scoliosis when we see it, but this article proves me wrong! The authors did a retrospective review of nearly 1300 spine MRI studies, assessed them for presence of scoliosis and also measured it. They found that scoliosis was present in 20% of studies with higher rates in females and those over 60 years of age. Scoliosis went unreported in 67% of cases particularly when the angle was less than 20 degrees. Spondylolisthesis was present in 15% of scoliosis patients and was reported in nearly all instances. Remember that scoliosis may be the cause of back pain in adults, and thus, it is important to mention it in our reports.
Attenuation of Cerebral Venous Contrast in Susceptibility-Weighted Imaging of Spontaneously Breathing Pediatric Patients Sedated with Propofol • J. Sedlacik, U. Löbel, M. Kocak, R.B. Loeffler, J.R. Reichenbach, A. Broniscer, Z. Patay, and C.M. Hillenbrand
We are using SWI more and more each day so it behooves us to be aware of artifacts and limitations associated with it. Since most children are sedated for MRI studies and the sedation changes cerebral hemodynamics, the authors hypothetized that sedation would also affect SWI. They went back and classified venous contrast as weak or strong in 125 SWI studies obtained under sedation. They also monitored some physiologic parameters and the cerebral blood flow with ASL perfusion. Venous contrast on SWI correlated with CBF and CO2 in the following way: when both were high, venous contrast was weak and when both were low, venous contrast was strong. Also, patients with high blood pressure showed strong SWI contrast. Thus, it is important to remember that venous contrast on SWI may be affected in sedated patients.
Functional Contrast-Enhanced CT For Evaluation of Acute Ischemic Stroke Does Not Increase the Risk of Contrast-Induced Nephropathy • F.O. Lima, M.H. Lev, R.A. Levy, G.S. Silva, M. Ebril, É.C. de Camargo, S. Pomerantz, A.B. Singhal, D.M. Greer, H. Ay, R. Gilberto González, W.J. Koroshetz, W.S. Smith, and K.L. Furie
This article is included in our new “Patient Safety” category, and therefore, I thought it prudent to list here since fellows and residents are usually the ones determining the protocols for studies. Patients with suspected stroke get CTA and CT perfusion studies and thus larger doses of iodinated contrast. The authors sought out to determine if this resulted in nephropathy (defined as a 25% increase in creatinine when compared to pre-CT levels). They assessed Cr levels in 575 patients who underwent CTA, CTA/CTP or CTA/CTP + DSA and used as controls 343 acute stroke patients who received no contrast. The incidence of nephropathy was 5% in those who received contrast vs. 10% in those who did not. DSA after CTA/CTP did not increase risk of nephropathy, and the authors concluded that doing DSA after dosing the patient for CTA/CTP is well tolerated.
