The utility of quantitative magnetic resonance angiography in the assessment of intracranial in-stent stenosis.

BACKGROUND AND PURPOSE: Noninvasive screening for intracranial in-stent stenosis is often limited by artifact because of the stent or associated coils. We aimed to determine the utility of quantitative MRA (QMRA) as a screening tool for detecting intracranial in-stent stenosis. METHODS: We reviewed 14 patients who had intracranial stent placement with follow-up QMRA and conventional angiography at our institution. Socio-demographic, medical, clinical, and imaging data were abstracted from medical charts. A blinded interventional neurologist reviewed all angiograms for presence of >50% in-stent stenosis. We tested QMRA (mL/min) at varying thresholds as a predictor of angiographic results. RESULTS: Among 14 patients (mean age, 62 years; 12 female, 2 male), 13 patients had Neuroform stents placed for wide-neck cerebral aneurysms and 1 patient had a Wingspan stent placement for atherosclerotic stenosis. Lesions were located in the intracranial internal carotid artery in 57.2% (n=8), the middle cerebral artery in 14.3% (n=2), and vertebrobasilar arteries in 28.6% (n=4). On follow-up angiography, 2 patients (14.3%) had >50% in-stent stenosis on angiography. Time-of-flight MRA was nondiagnostic in each case because of artifact from the stent or coils. A >20% reduction in vessel-specific blood flow by QMRA was associated with presence of >50% in-stent stenosis on angiography (P=0.033). As a screening tool to predict >50% angiographic in-stent stenosis, the sensitivity, specificity, positive predictive value, and negative predictive value of QMRA were 100%, 92%, 67%, and 100%, respectively. CONCLUSIONS: We found that QMRA is a promising screening tool to detect intracranial in-stent stenosis. Future prospective studies should focus on whether QMRA has a role in the detection of radiographic restenosis and prediction of clinical events.

Survival Prediction in Ambulatory Patients With Stage III/IV Non-Small Cell Lung Cancer Using the Palliative Performance Scale, ECOG, and Lung Cancer Symptom Scale.

OBJECTIVES: Patients with advanced non-small cell lung cancer (NSCLC) have a life expectancy of less than 1 year. Therefore, it is important to maximize their quality of life and find a tool that can more accurately predict survival. MATERIALS: The Palliative Performance Scale (PPS) is used to predict survival for patients with advanced disease based on functional dimensions. The value of the PPS in ambulatory patients with cancer has not been examined to date. The Lung Cancer Symptom Scale (LCSS) measures six major symptoms and their effect on symptomatic distress and activity. We evaluated 62 patients with stage III or IV NSCLC and Eastern Cooperative Oncology Group (ECOG) Scale Score ≥1 at baseline in a thoracic oncology clinic. In all, 62 patients had LCSS and PPS evaluated at baseline and 54 patients had 4-week follow-up using LCSS, PPS, and ECOG. RESULTS: Fifty-four patients completed baseline and follow-up. Mean age was 63.7 years. Sixty-three percent were receiving chemotherapy at evaluation. Seventeen patients died. Mean baseline measures were LCSS 6.18 (1-14); PPS 66.6 (40-90); and ECOG 1.82 (1-4). Censored survival times were calculated from enrollment of the first patient for 380 days. A proportional hazardous model was computed for survival status. Hazard ratios for death were 1.25 (P = .013) for LCSS, 2.12 (P = .027) for ECOG, and 1.02 for PPS (P = .49). CONCLUSIONS: The LCSS predicted prognosis best in this study. The PPS did not accurately predict prognosis in our patient population.

Hemodynamic changes following wingspan stent placement--a quantitative magnetic resonance angiography study.

BACKGROUND: Quantitative magnetic resonance angiography (QMRA) is a noninvasive imaging modality that provides anatomic and physiologic measurements of arteries. We used QMRA to assess hemodynamic changes following Wingspan stent placement for intracranial stenosis. METHODS: We reviewed patients treated with Wingspan stents for intracranial stenosis who had baseline and follow-up QMRA data. We compared volumetric flow rates (VFRs) (mL/minute) pre- and poststenting using paired t-tests. P<.05 was considered significant. RESULTS: Among 9 patients (mean age 65.8 years, mean 71% degree of stenosis), lesions were located in the supraclinoid internal carotid arteries in 3, middle cerebral arteries in 3, and intracranial vertebrobasilar arteries in 3. VFR and degree of stenosis were moderately correlated (r=-.670, P=.002). The mean VFR in the stenotic artery increased from 81.2 mL/minute to 133.3 mL/minute (P=.020) or by 64.2% after stenting. Total cerebral blood flow, flow in nonstented vessels, and collateral flow in circle of Willis vessels did not significantly change. CONCLUSION: We found that QMRA is a promising noninvasive method for the measurement of cerebral hemodynamics following intracranial Wingspan stent placement. Larger prospective studies are needed to confirm our findings.

Onyx embolization of arteriovenous malformations using 2 microcatheters.

OBJECTIVE: To report an operative technique using 2 microcatheters placed in different arterial pedicles for Onyx (ev3 Neurovascular, Inc, Irvine, CA) embolization of cerebral arteriovenous malformations (AVMs). TECHNIQUE: Two cases illustrate this approach to embolization of AVMs. Microcatheters are placed in 2 different arterial pedicles of the AVM. Subsequently, the embolic material is injected in an alternate fashion between the microcatheters until occlusion of the AVM. CONCLUSION: The 2-microcatheter technique for embolization of AVMs with Onyx was performed safely. The technique allowed for less interruptions of injection and better control of the reflux of Onyx in the arterial pedicle during treatment. This technique presents an alternate approach to conventional AVM embolization.

Stent remodeling technique for coiling of ruptured wide-neck cerebral aneurysms: case report.

OBJECTIVE: To describe a novel stent remodeling technique for the coiling of ruptured wide-neck cerebral aneurysms. CLINICAL PRESENTATION: A 46-year-old man presented with acute subarachnoid hemorrhage (Hunt and Hess grade IV), intracerebral hemorrhage, and hydrocephalus. Cerebral angiography revealed a wide-neck small anterior communicating artery aneurysm. Conventional coiling was not successful because of coil instability and compromise of the dominant anterior cerebral artery. TECHNIQUE: A 6-French shuttle sheath (Cook Medical, Indianapolis, IN) was advanced from a right femoral approach into the right common carotid artery. To protect the parent vessel during coiling without compromising blood flow, a Prowler Select Plus catheter (Cordis Corporation, Bridgewater, NJ) was navigated across the aneurysm neck. Subsequently, an Enterprise stent (22-mm length; Cordis Corporation) was partially deployed across the aneurysm's wide neck. It was very important to watch the distal markers of the stent and lock the stent delivery wire to the Prowler Select Plus with a hemostatic valve once the stent was halfway deployed. This maneuver was essential to prevent further deployment of the stent. The SL-10 microcatheter and Synchro 14 wire (Boston Scientific, Natick, MA) were carefully navigated to the aneurysm passing through the partially deployed stent. Coils were then delivered to the aneurysm using the stent as a scaffold. After coiling, the SL-10 microcatheter was removed and the stent was recaptured into the Prowler Select Plus catheter. During the recapture, there was initial resistance. This was easily overcome after deploying the stent a little more before resheathing. During the procedure, the patient received 2000 U of heparin after the first coil was detached in the aneurysm. CONCLUSION: The stent remodeling technique is a novel endovascular technique that can be used to treat ruptured wide-neck aneurysms and maintain patency of parent vessels, avoiding the use of antiplatelet therapy in acute subarachnoid hemorrhage.