First experience of evaluation of the impact of high-matrix size reconstruction in image quality in arterial CT runoff studies of the lower extremities.

OBJECTIVES: To determine whether image reconstruction with a higher matrix size improves image quality for lower extremity CTA studies. METHODS: Raw data from 50 consecutive lower extremity CTA studies acquired on two MDCT scanners (SOMATOM Flash, Force) in patients evaluated for peripheral arterial disease (PAD) were retrospectively collected and reconstructed with standard (512 × 512) and higher resolution (768 × 768, 1024 × 1024) matrix sizes. Five blinded readers reviewed representative transverse images in randomized order (150 total). Readers graded image quality (0 (worst)-100 (best)) for vascular wall definition, image noise, and confidence in stenosis grading. Ten patients' stenosis scores on CTA images were compared to invasive angiography. Scores were compared using mixed effects linear regression. RESULTS: Reconstructions with 1024 × 1024 matrix were ranked significantly better for wall definition (mean score 72, 95% CI = 61-84), noise (74, CI = 59-88), and confidence (70, CI = 59-80) compared to 512 × 512 (wall = 65, CI = 53 × 77; noise = 67, CI = 52 × 81; confidence = 62, CI = 52 × 73; p = 0.003, p = 0.01, and p = 0.004, respectively). Compared to 512 × 512, the 768 × 768 and 1024 × 1024 matrix improved image quality in the tibial arteries (wall = 51 vs 57 and 59, p < 0.05; noise = 65 vs 69 and 68, p = 0.06; confidence = 48 vs 57 and 55, p < 0.05) to a greater degree than the femoral-popliteal arteries (wall = 78 vs 78 and 85; noise = 81 vs 81 and 84; confidence = 76 vs 77 and 81, all p > 0.05), though for the 10 patients with angiography accuracy of stenosis grading was not significantly different. Inter-reader agreement was moderate (rho = 0.5). CONCLUSION: Higher matrix reconstructions of 768 × 768 and 1024 × 1024 improved image quality and may enable more confident assessment of PAD. CLINICAL RELEVANCE STATEMENT: Higher matrix reconstructions of the vessels in the lower extremities can improve perceived image quality and reader confidence in making diagnostic decisions based on CTA imaging. KEY POINTS: • Higher than standard matrix sizes improve perceived image quality of the arteries in the lower extremities. • Image noise is not perceived as increased even at a matrix size of 1024 × 1024 pixels. • Gains from higher matrix reconstructions are higher in smaller, more distal tibial and peroneal vessels than in femoropopliteal vessels.

A minimally invasive approach for management of pancreaticoduodenal artery and gastroduodenal artery aneurysm with celiac artery occlusion.

Management of pancreaticoduodenal artery aneurysms (PDAAs) and gastroduodenal artery aneurysms (GDAAs) with concomitant celiac occlusion represents a challenging clinical scenario. Here, we describe a 62-year-old female with PDAA and GDAA complicated by celiac artery occlusion due to median arcuate ligament syndrome. We used a staged, minimally invasive approach consisting of: (1) a robotic median arcuate ligament release; (2) endovascular celiac artery stenting; and (3) visceral aneurysm coiling. The findings from this case report represent a novel treatment strategy for the management of PDAA/GDAA with celiac artery compression secondary to median arcuate ligament syndrome.

Utility of CBCT and AVD for intraprocedural diagnosis and treatment of lower GI bleeding.

BACKGROUND: Intraprocedural Cone Beam CT (CBCT) is assessed to examine if use improves diagnosis and embolization rates of acute lower GI bleed (LGIB) and if automatic vessel detection (AVD) software can identify feeding vessels (FV) for embolization. METHODS: Patients with inconclusive DSA findings had CBCT and retrospective analysis with AVD software (Innova 3100, GE Company, USA). Technical success was defined as the ability to detect a lower GIB site while clinical success was defined as successful embolization without evidence of rebleeding or death within 30 days. AVD technical success was defined by the ability to identify the FV on both CTA and CBCT upon independent review by 3 blinded IRs, who also assigned a degree of certainty on a 5-point Likert scale. RESULTS: 74 patients in total were treated for lower GI bleed of which 34 had indeterminate DSA. Of those, 10 patients received DSA only, of which 1 was super selective. 24 patients with GIB on pre-procedural CTA and inconclusive DSA underwent CBCT. Use of CBCT identified 9 bleeds not seen on DSA and an additional source artery in 1 case representing a 42% change in intraprocedural management as all findings were embolized. When a bleed could not be identified on CBCT, but the FV could be identified on CTA, the same suspected FV could be selected on AVD 62% of the time with an average certainty of 4.0. CONCLUSION: CBCT is useful in the intraprocedural detection of GIB when DSA is indeterminate. Furthermore, AVD software can feasibly be utilized to accurately identify FVs for empiric treatment when intraprocedural imaging is inconclusive. LEVEL OF EVIDENCE: Level III, therapeutic study.

Probing gut-brain links in Alzheimer's disease with rifaximin.

Gut-microbiome-inflammation interactions have been linked to neurodegeneration in Alzheimer's disease (AD) and other disorders. We hypothesized that treatment with rifaximin, a minimally absorbed gut-specific antibiotic, may modify the neurodegenerative process by changing gut flora and reducing neurotoxic microbial drivers of inflammation. In a pilot, open-label trial, we treated 10 subjects with mild to moderate probable AD dementia (Mini-Mental Status Examination (MMSE) = 17 ± 3) with rifaximin for 3 months. Treatment was associated with a significant reduction in serum neurofilament-light levels (P < .004) and a significant increase in fecal phylum Firmicutes microbiota. Serum phosphorylated tau (pTau)181 and glial fibrillary acidic protein (GFAP) levels were reduced (effect sizes of -0.41 and -0.48, respectively) but did not reach statistical significance. In addition, there was a nonsignificant downward trend in serum cytokine interleukin (IL)-6 and IL-13 levels. Cognition was unchanged. Increases in stool Erysipelatoclostridium were correlated significantly with reductions in serum pTau181 and serum GFAP. Insights from this pilot trial are being used to design a larger placebo-controlled clinical trial to determine if specific microbial flora/products underlie neurodegeneration, and whether rifaximin is clinically efficacious as a therapeutic.