Luminal Cross-sectional Area Research Articles

Airway compliance measured by anatomic optical coherence tomography.

Quantification of airway compliance can aid in the diagnosis and treatment of obstructive airway disorders by detecting regions vulnerable to collapse. Here we evaluate the ability of a swept-source anatomic optical coherence tomography (SSaOCT) system to quantify airway cross-sectional compliance (CC) by measuring changes in the luminal cross-sectional area (CSA) under physiologically relevant pressures of 10-40 cmH2O. The accuracy and precision of CC measurements are determined using simulations of non-uniform rotation distortion (NURD) endemic to endoscopic scanning, and experiments performed in a simplified tube phantom and ex vivo porcine tracheas. NURD simulations show that CC measurements are typically more accurate than that of the CSAs from which they are derived. Phantom measurements of CSA versus pressure exhibit high linearity (R2>0.99), validating the dynamic range of the SSaOCT system. Tracheas also exhibited high linearity (R2 = 0.98) suggestive of linear elasticity, while CC measurements were obtained with typically ± 12% standard error.

Changes of choroidal structure after intravitreal aflibercept therapy for polypoidal choroidal vasculopathy

AimsTo quantify the changes of the choroidal structure in the enhanced depth imaging optical coherence tomographic (EDI-OCT) images after intravitreal aflibercept (IVA) injections for polypoidal choroidal vasculopathy (PCV).MethodsRetrospective, observational case...

Structural implications of fenestrated stent graft misalignment

BackgroundEndovascular aneurysm repair is a minimally-invasive method for the treatment of abdominal aortic aneurysms. For aneurysms that involve the visceral arteries, a custom-made stent graft with fenestrations for the branch arteries is required. The purpose of the current study is to evaluate the structural impact of misaligned fenestrations with respect to luminal patency and proximal aortic neck apposition in an in vitro model. MethodsA custom apparatus was used to evaluate seven Anaconda and three Zenith fenestrated stent grafts. All stent grafts were evaluated at 10° increments of stent/fenestration misalignment up to 80°. Images were captured at each interval and the luminal cross-sectional area and wall apposition were measured. ResultsThe Anaconda stent graft, which has an unsupported main body, demonstrated a linear reduction in luminal patency at increasing angles of misalignment (P < 0.0001). Stent/fenestration misalignments of 20° and 80° resulted in decreases in mean luminal patency of 14% and 54% respectively. The Zenith stent graft demonstrated a similar decrease in luminal patency, starting at misalignments of ≥40° (P < 0.0001). However, with stent/fenestration misalignments of ≥30°, apposition between the Zenith stent graft and the simulated aortic neck was compromised suggesting the creation of a type Ia endoleak. ConclusionsBoth the Anaconda and Zenith devices behave adversely at extreme angles of misalignment with luminal narrowing in the Anaconda device and loss of wall apposition in the Zenith device; however, both stent grafts appear to be equivalent at low angles of misalignment.

Coronary artery plaque imaging: Comparison of black-blood MRI and 64-multidetector computed tomography

ObjectiveTo comparatively evaluate black-blood coronary arterial wall MRI and 64-multidetector computed tomography (64-MDCT) for detection and classification of coronary artery plaques. MethodsWe included 15 patients with confirmed coronary artery plaques in the proximal or middle segments of coronary arteries by 64-MDCT, who underwent black-blood coronary wall MRI at 1.5 T within 10 days. Cross-sectional coronary wall images were acquired using a 2D double-inversion-recovery, electrocardiograph-triggered, navigator-gated, fat-suppressed, turbo-spin-echo sequence on the coronary arteries with lesions from the ostium to the middle segment continuously without gap. The vessel cross-sectional area (CSA), luminal CSA, maximal wall thickness, plaque burden, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR) were measured in each slice and subsequently compared with computed tomography angiography (CTA) images. CTA images were divided into 5-mm segments for side-by-side comparison with MRI. ResultsOf the 15 patients, 12 were enrolled in the study. Coronary plaques were found in 46 slices on both CTA and MRI. Plaques were classified to 3 groups based on CTA: calcified plaques (n = 11), soft plaques (n = 23), and mixed plaques (n = 12). In MRI, the plaque burden, maximal wall thickness, SNR, and CNR in the coronary walls containing plaques were greater than in the normal coronary walls (0.83 ± 0.08 vs. 0.73 ± 0.08, 1.88 ± 0.51 vs. 1.51 ± 0.26 mm, 12.95 ± 2.78 vs. 9.93 ± 2.31, and 6.76 ± 2.52 vs. 3.89 ± 1.54, respectively; P < 0.05). The luminal CSA at the plaque was smaller than in normal coronary walls (2.50 ± 1.50 vs. 4.72 ± 2.28 mm2; P < 0.05). The SNR in the soft plaque was significantly greater than in calcified and mixed plaques (P < 0.05). ConclusionsCoronary wall MRI can identify coronary plaques in the proximal and middle segments and has the potential to differentiate plaque types based on signal intensity.

Utility of Multimodality Imaging in the Morphologic Characterization of Anomalous Aortic Origin of a Coronary Artery.

Anomalous aortic origin of a coronary artery from the wrong Sinus of Valsalva (AAOCA) is a rare congenital anomaly and is associated with sudden cardiac death. Morphologic features considered to be "high risk" are significant luminal narrowing, acute coronary angulation at its origin, intramural course, and long interarterial course. A consistent approach for characterization of these features is lacking. A retrospective single-center review of all patients diagnosed with AAOCA using echocardiogram and computed tomography (CT)/magnetic resonance imaging (MRI) studies was performed. Twenty-nine patients were identified (25 using CT and 4 using MRI) with subsequent three-dimensional data sets. The MRI data sets lacked adequate resolution and were excluded. Twenty-five patients (median age 15.1, range 10-39.5 years, 72% male) were further analyzed using echocardiogram and CT. Morphologic assessment focused on luminal stenosis, coronary angulation, and interarterial length. Additional morphologic features focusing on cross-sectional area and degree of ellipticity were also assessed. Echocardiography tended to yield smaller measurements compared to CT and had poor interobserver reproducibility for measurements pertaining to the narrowest proximal and distal coronary segments. Computed tomography showed good inter-/intraobserver reproducibility for the same. Agreement between both modalities for coronary angulation at its origin was excellent. There was good agreement for measurements of interarterial length between echocardiography and CT, but echocardiography had superior reproducibility. Assessment of luminal cross-sectional area and elliptical shape by CT had excellent inter-/intraobserver reproducibility. The combination of echocardiography and CT characterizes morphologic features of anomalous origin of the coronary artery more reliably than either modality alone.

Sa1346 Measuring Dynamic Changes in Luminal Cross Sectional Area Along the Length of the Esophagus during Peristalsis Using Novel Impedance Methodology

Sa1346 Measuring Dynamic Changes in Luminal Cross Sectional Area Along the Length of the Esophagus during Peristalsis Using Novel Impedance Methodology

The protective effect of resveratrol on arterial remodeling in spontaneous hypertensive rats

Objective To observe the effect of resveratrol on arterial remodeling in spontaneous hypertensive rats. Methods Spontaneous hypertensive rats (SHRs, n=20) and Wistar-Kyoto rats (WKYs, n=10 ) were randomly assigned to three groups: control group, model group and resveratrol group. Systolic blood pressure (SBP) and pulse wave velocity (PWV) of the three groups was observed. Morphological observations were obtained by hematoxylin and eosin or victoria blue and picrosirius red. The content of nitric oxide (NO) and endothelin-1 (ET-1) were determined to assess the endothelial function. Oxidative stress was assessed by malondialdehyde (MDA), hydrogen peroxide (H2O2), and activities of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). Results Compared with control group, SBP, PWV, wall thickness, wall-lumen ratio, vascular cross-sectional area (VCSA), luminal cross-sectional area (LCSA) and collagen-elastic ratio were increased, and the levels of NO, SOD, CAT in rat aortic tissues were decreased, while ET-1, MDA, H2O2 levels in rat aortic tissues were enhanced in model group at the end of 22 weeks. After the treatment of resveratrol, SBP had no significantly difference between model and resveratrol groups, while PWV, aortic wall thickness, wall-lumen ratio, VCSA, LCSA and collagen-elastic ratio were decreased in resveratrol group as compared with model group 〔(6681.1±2154.9) cm/s vs. (4283.1±946.1) cm/s, (234.7±51.8) μm vs. (123.4±21.5) μm, (10.3±2.3) % vs. (5.8±1.4) %, (6.4±0.4) mm2vs. (4.8±0.6) mm2, (4.1±0.1) mm2vs. (3.2±0.4) mm2, (1.1±0.3) vs. (0.4±0.2), P<0.05 or 0.01〕. Compared with model group, the expressions of NO, SOD, CAT in rat aortic tissues were increased and levels of ET-1, MDA, H2O2 in rat aortic tissues were decreased in resveratrol group after treatment of resveratrol (P<0.01 or P<0.05). Conclusions Resveratrol has an antioxidant effect, and it could attenuate arterial remodeling by improving oxidative stress. Key words: Resveratrol; Oxidative stress; Hypertension

Automated continuous quantitative measurement of proximal airways on dynamic ventilation CT: initial experience using an ex vivo porcine lung phantom.

BackgroundThe purpose of this study was to evaluate the feasibility of continuous quantitative measurement of the proximal airways, using dynamic ventilation computed tomography (CT) and our research software.MethodsA porcine lung that was removed during meat processing was ventilated inside a chest phantom by a negative pressure cylinder (eight times per minute). This chest phantom with imitated respiratory movement was scanned by a 320-row area-detector CT scanner for approximately 9 seconds as dynamic ventilatory scanning. Obtained volume data were reconstructed every 0.35 seconds (total 8.4 seconds with 24 frames) as three-dimensional images and stored in our research software. The software automatically traced a designated airway point in all frames and measured the cross-sectional luminal area and wall area percent (WA%). The cross-sectional luminal area and WA% of the trachea and right main bronchus (RMB) were measured for this study. Two radiologists evaluated the traceability of all measurable airway points of the trachea and RMB using a three-point scale.ResultsIt was judged that the software satisfactorily traced airway points throughout the dynamic ventilation CT (mean score, 2.64 at the trachea and 2.84 at the RMB). From the maximum inspiratory frame to the maximum expiratory frame, the cross-sectional luminal area of the trachea decreased 17.7% and that of the RMB 29.0%, whereas the WA% of the trachea increased 6.6% and that of the RMB 11.1%.ConclusionIt is feasible to measure airway dimensions automatically at designated points on dynamic ventilation CT using research software. This technique can be applied to various airway and obstructive diseases.

Histopathological effect of balloon dilation in a live rabbit: Implications for the pediatric airway.

To examine the short- and long-term histopathologic changes that occur in the subglottis in response to airway balloon dilation (ABD) with different balloon diameters and inflation pressures. Prospective animal study using forty-two 8-month old New Zealand white rabbits at an academic animal research facility. Thirty-nine live New Zealand rabbits underwent a single ABD with diameters ranging from 6.0 mm to 10.0 mm and with pressures between 5.0 atmospheres (atm) to 15.0 atm. Animals were euthanized on postoperative days (POD) 1, 7, and 30, and the histopathological changes of the subglottis were examined. Three rabbits served as controls and underwent no ABD. The subglottic airway diameter of all specimens measured 5.4 mm. When examining the fracture rate by balloon diameter, we found the following: 0 of 6 (0%) at 6 mm, 0 of 9 (0%) at 7 mm, 6 of 9 (67%) at 8 mm, 8 of 9 (89%) at 9 mm, and 6 of 6 (100%) at 10 mm. There was a statistically significant relationship with the rate of cricoid fracture as balloon diameter increased (P < .0001). All fractures occurred at the anterior cricoid lamina. On POD 1, we found mild ulceration in 5 of 6 (83%) using a 6-mm or 7-mm balloon and in 0 of 6 (0%) using an 8-mm, 9-mm, or 10-mm balloon; and moderate/severe ulceration in 1 of 6 (16.67%) using a 6-mm or 7-mm balloon and in 11 of 11 (100%) using an 8-mm, 9-mm, or 10-mm balloon (P < .0001). Also on POD 1, we found mild edema in 6 of 6 (100%) using a 6-mm or 7-mm balloon and in 5 of 11 (45%) using an 8-mm, 9-mm, or 10-mm balloon; and moderate/severe edema in 0 of 6 (0%) using a 6-mm/7-mm balloon and in 6 of 11 (55%) using an 8-mm, 9-mm, or 10-mm balloon (P =.048). On POD 7, we found fibroplasia in 5 of 6 (83%) using a 6-mm or 7-mm balloon and in 1 of 7 (14%) using an 8-mm, 9-mm, or 10-mm balloon; and moderate/severe fibroplasia in 1 of 6 (17%) using a 6-mm or 7-mm balloon and in 6 of 7 (86%) using an 8-mm, 9-mm, or 10-mm balloon (P =.029). Also on POD7, we found granulation tissue in 0 of 6 (0%) using a 6-mm or 7-mm balloon and in 5 of 7 (71%) using an 8-mm, 9-mm, or 10-mm balloon (P = .021). On POD 30, we found no fibrosis in 0 of 3 (0%) using a 7-mm balloon, mild fibrosis in 1 of 6 (16.67%), and moderate/severe fibrosis in 5 of 6 (83%) using an 8-mm or 9-mm balloon (P = .048). Also on POD 30, we found the mean subglottic cross-sectional luminal area was 23.79 mm(2) with a 7-mm balloon and 29.28 mm(2) with an 8-mm or 9-mm balloon (P = .019). Inflation pressure alone had no correlation with mucosal injury or probability of cricoid fracture. Airway balloon dilation with balloon diameters that exceeded the airway diameter by 2.6 mm was associated with cricoid fractures. All cricoid fractures localized to the anterior cricoid lamina. Balloon diameters larger than the airway diameter by 2.6 mm resulted in a larger subglottic cross-sectional luminal area on POD 30. Airway balloon dilation with balloon diameters that could generate a cricoid fracture created more mucosal injury on POD 0, 1, and 7 than smaller balloon diameters. The histopathological effects of airway balloon dilation observed on POD 0, 1, and 7 resolved by POD 30. When balloon diameter is kept constant, inflation pressure alone had no correlation with mucosal injury or probability of cricoid fracture. NA (animal study). Laryngoscope, 125:S1-S11, 2015.

Novel Strategy for Temporary Decompression of the Lower Urinary Tract in Neonates Using a Ureteral Stent

In children with congenital obstructive uropathy, including posterior urethral valves, lower urinary tract decompression is recommended pending definitive surgical intervention. Current options, which are limited to a feeding tube or Foley catheter, pose unappreciated constraints in luminal diameter and are associated with potential problems. We assess the impact of luminal diameter on the current draining options and present a novel alternative method, repurposing a widely available stent that optimizes drainage. We retrospectively reviewed patients diagnosed with posterior urethral valves between January 2013 and December 2014. In all patients a 6Fr 12 cm Double-J ureteral stent was advanced over a guidewire in a retrograde fashion into the bladder. Luminal flow and cross-sectional areas were also assessed for each of 3 tubes for urinary drainage, ie 6Fr Double-J stent, 5Fr feeding tube and 6Fr Foley catheter. A total of 30 patients underwent uneventful bedside Double-J stent placement. Mean ± SD age at valve ablation was 28.5 ± 16.6 days. Mean ± SD peak serum creatinine was 2.23 ± 0.97 mg/dl after birth and 0.56 ± 0.22 mg/dl at the procedure. Urine output after stent placement was excellent in all patients. The Foley catheter and feeding tube drained approximately 18 and 6 times more slowly, respectively, and exhibited half the calculated cross-sectional luminal area compared to the Double-J stent. Use of Double-J stents in neonates with posterior urethral valves is a safe and effective alternative method for lower urinary tract decompression that optimizes the flow/lumen relationship compared to conventional drainage options.

Measurement of peak esophageal luminal cross-sectional area utilizing nadir intraluminal impedance.

Multichannel intraluminal impedance (MII) is currently used to monitor gastroesophageal reflux and esophageal bolus clearance. We describe a novel methodology to measure maximal luminal cross-sectional area (CSA) during bolus transport from MII measurements. Studies were conducted in-vitro (test tubes) and in-vivo (healthy subjects). Concurrent MII, high resolution manometry, and intraluminal ultrasound (US) images were recorded 7-cm above the lower esophageal sphincter. Swallows with two concentrations of saline, 0.1 and 0.5 N, of bolus volumes 5, 10, and 15 cc were performed. The CSA was estimated by solving two algebraic Ohm's law equations, resulting from the two saline solutions. The CSA calculated from impedance method was compared with the CSA measured from the intraluminal US images. The CSA measured in duplicate from B-mode US images showed a mean difference between the two manual delineations to be near zero, and the repeatability coefficient was within 7.7% of the mean of the two CSA measurements. The calculated CSA from the impedance measurements strongly correlated with the US measured CSA (R(2) ≅ 0.98). A detailed statistical analysis of the impedance and US measured CSA data indicated that the 95% limits of agreement between the two methods ranged from -9.1 to 13 mm(2) . The root mean square error of the two measurements was 4.8% of the mean US-measured CSA. We describe a novel methodology to measure peak esophageal luminal CSA from the nadir impedance during peristalsis. Further studies are needed to determine if it is possible to measure patterns of luminal distension during peristalsis across the entire length of the esophagus from the MII recordings.

Utilizing functional lumen imaging probe topography to evaluate esophageal contractility during volumetric distention: a pilot study.

The functional lumen imaging probe (FLIP) measures luminal cross-sectional area and pressure during volumetric distension. By applying novel customized software to produce FLIP topography plots, organized esophageal contractility can be visualized and analyzed. We aimed to describe the stimulus thresholds and contractile characteristics for distension-induced esophageal body contractility using FLIP topography in normal controls. Ten healthy controls were evaluated during endoscopy with FLIP. During stepwise bag distension, simultaneous intra-bag pressure and luminal diameter measurements were obtained and exported to a MatLab program to generate FLIP topography plots. The distension volume, intra-bag pressure, and maximum esophageal body diameters were measured for the onset and cessation of repetitive antegrade contractions (RACs). Contraction duration, interval, magnitude, and velocity were measured at 8 and 3-cm proximal to the esophagogastric junction. Eight of ten subjects demonstrated RACs at a median onset volume of 29 mL (IQR: 25-38.8), median intra-bag pressure of 10.7 mmHg (IQR: 8.6-15.9), and median maximum esophageal body diameter of 18.5 mm (IQR: 17.5-19.6). Cessation of RACs occurred prior to completion of the distension protocol in three of the eight subjects exhibiting RACs. Values of the RAC-associated contractile metrics were also generated to characterize these events. Distension-induced esophageal contractions can be assessed utilizing FLIP topography. RACs are a common finding in asymptomatic controls in response to volume distention and have similar characteristics to secondary peristalsis and repetitive rapid swallows.

Nebivolol to attenuate the effects of hyper-homocysteinaemia in rats

ObjectiveThis study investigated the prophylactic effect of nebivolol against hyper-homocysteinaemia (hHcy) induced oxidative stress in brain, heart, liver and kidney tissues and histomorphometric changes in the thoracic aorta. MethodsTwenty-four adult male Wistar rats were divided into a control, nebivolol, hHcy and nebivolol + hHcy group. hHcy was induced by oral administration of l-methionine (1 g/kg/day) for 28 days. 10 mg/kg/day nebivolol was administered orally for 28 days. Malondialdehyde (MDA) and glutathione (GSH) levels and catalase (CAT) and superoxide dismutase (SOD) activities in the tissues were determined. The total cross-sectional area (TCSA), luminal cross-sectional area (LCSA) and intima-media thickness (IMT) were measured in the thoracic aorta. ResultsHomocysteine (Hcy) levels were lower in the nebivolol + hHcy group than in the hHcy group. Nebivolol treatment significantly decreased high MDA levels in the brain, heart and liver tissues. The level of GSH was higher in the brain, heart and kidney tissues of the nebivolol + hHcy group (P < 0.001). The activity of CAT increased only in the kidney tissue of the nebivolol + hHcy group (P < 0.01), and the activity of SOD was significantly increased in all the tissues in this group. Increased TCSA and IMT in the nebivolol + hHcy group were significantly decreased after nebivolol administration. The LCSA was significantly higher in the hHcy group than the control group, probably due to outward vascular remodelling. ConclusionNebivolol treatment may be useful in different clinical scenarios where hHcy affects physiopathological pathways.

Exclusive Enteral Nutritional Therapy Can Relieve Inflammatory Bowel Stricture in Crohn’s Disease

To examine the efficiency of exclusive enteral nutrition (EEN) in relieving inflammatory bowel stricture in patients with Crohn's disease (CD). Patients with CD usually develop bowel strictures due to transmural edema of intestinal wall, which can potentially be managed with conservative medical treatment. Previous studies showed that EEN therapy could induce clinical remission through its anti-inflammation effect. We achieved a prospective observational study. CD patients with inflammatory bowel stricture were preliminarily differentiated from a fibrous one, and further treated with EEN therapy for 12 weeks. Demographics and clinical variables were recorded. Nutritional (body mass index, albumin, pre-albumin, transferrin, etc.), inflammatory (C-reactive protein, erythrocyte sedimentation rate, white blood cell, etc.), and radiologic parameters (bowel wall thickness, luminal diameter, and luminal cross-sectional area) were evaluated at baseline, week 4, and week 12, respectively. Between May 2012 and January 2013, 65 patients with CD were preliminarily diagnosed with inflammatory bowel stricture and 6 patients were further excluded. Among the remaining 59 cases, 50 patients (84.7%) finished the whole EEN treatment, whereas the other 9 patients (15.3%) gained progressive bowel obstruction resulting in surgery. Intention-to-treat analyses showed that 48 patients (81.4%) achieved symptomatic remission, 35 patients (53.8%) achieved radiologic remission, and 42 patients (64.6%) achieved clinical remission. Among those patients who complete the whole EEN therapy, inflammatory, nutritional, and radiologic parameters improved significantly compared with baseline. Of note, the average luminal cross-sectional area at the site of stricture increased approximately 331% at week 12 (195.7 ± 18.79 vs. 59.09 ± 10.64 mm, P<0.001). EEN therapy can effectively relieve inflammatory bowel stricture in CD, which replenishes roles of enteral nutrition in the treatment of CD. Further studies are expected to investigate the underlying mechanisms of this effect in the future.

Esophageal distension during bolus transport: can it be detected by intraluminal impedance recordings?

Esophageal multiple intraluminal impedance (MII) measurement has been used to detect gastro-esophageal reflux and bolus transport. It is not clear if MII can detect changes in luminal cross sectional area (CSA) during bolus transport. Intraluminal ultrasound (US) images, MII, and high resolution manometry (HRM) were recorded simultaneously to determine temporal relationship between CSA and impedance during esophageal bolus transport and to define the relationship between peak distension and nadir impedance. Studies were conducted in five healthy subjects. MII, HRM, and US images were recorded 6cm above LES. Esophageal distensions were studied during swallows and injections of 0.5N saline bolus into the esophagus. Temporal change in esophageal CSA correlates with changes in impedance (r-value: mean±SD=-0.80±0.08, range: -0.94 to -0.66). Drop in impedance during distension occurs as a two-step process; initial large drop associated with onset of CSA increase, followed by a small drop during which majority of the CSA increase occurs. Peak CSA and nadir impedance occur within 1s of each other. Increase in swallow and injection volumes increased the CSA, had no effect on large drop but increased the small drop amplitude. We observed a significant correlation between peak CSA and nadir impedance (r=-0.90, p<0.001) and a better correlation between peak CSA and inverse impedance (r=0.94, p<0.001). Further studies are needed to confirm that intraluminal impedance recordings may be used to measure luminal CSA during esophageal bolus transport.

Cardio-ankle vascular index (CAVI) correlates with aortic stiffness in the thoracic aorta using ECG-gated multi-detector row computed tomography

BackgroundThe cardio-ankle vascular index (CAVI) is an arterial stiffness index based on the stiffness parameter β, which is essentially independent of blood pressure. The objective of this study was to determine whether CAVI correlates with the regional stiffness parameter β and pulse wave velocity (PWV) in the thoracic aorta calculated from ECG-gated multi-detector row computed tomography (MDCT). Methods and resultsForty-nine patients who underwent coronary MDCT for suspicious coronary artery disease were recruited. The largest and smallest vessel luminal cross-sectional areas of the thoracic aorta were measured from MDCT images to calculate PWV and stiffness parameter β of the ascending and descending aorta. CAVI was also measured by VaSera VS-1000.In univariate analysis, CAVI significantly correlated with regional stiffness parameter β and PWV, which was influenced by the inevitable part of the aging process in the ascending (r = 0.485, P < 0.001; r = 0.483, P < 0.001) and descending aortas (r = 0.304, P = 0.034; r = 0.327, P = 0.022), respectively. The regional stiffness parameter β did not correlate with systolic blood pressure (SBP), although the PWV correlated with SBP. In multivariate analysis, CAVI independently correlated with the stiffness parameter β, but not with the PWV. ConclusionThese data suggest that CAVI, which correlated with stiffness parameter β in the thoracic aorta, has a potential role in evaluating integrated arterial stiffness including that of the central aorta.

Defective Mucosal Movement at the Gastroesophageal Junction in Patients with Gastroesophageal Reflux Disease

Little is known about the role of muscularis mucosa at the gastroesophageal junction (GEJ). To evaluate the movement of the mucosa/muscularis-mucosa/submucosa (MMS) at the GEJ in normal subjects and in patients with gastroesophageal reflux disease (GERD). Gastroesophageal junctions of 20 non-GERD subjects and 10 patients with GERD were evaluated during 5 mL swallows using two methods: in high-resolution endoluminal ultrasound and manometry, the change in the GEJ luminal pressures and cross-sectional area of esophageal wall layers were measured; in abdominal ultrasound, the MMS movement at the GEJ was analyzed. Endoluminal ultrasound: In the non-GERD subjects, the gastric MMS moved rostrally into the distal esophagus at 2.17 s after the bolus first reached the GEJ. In GERD patients, the gastric MMS did not move rostrally into the distal esophagus. The maximum change in cross-sectional area of gastroesophageal MMS in non-GERD subjects and in GERD patients was 289 % and 183%, respectively. Abdominal ultrasound: In non-GERD subjects, the gastric MMS starts to move rostrally significantly earlier and to a greater distance than muscularis propria (MP) after the initiation of the swallow (1.75 vs. 3.00 s) and (13.97 vs. 8.91 mm). In GERD patients, there is no significant difference in the movement of gastric MMS compared to MP (6.74 vs. 6.09 mm). The independent movement of the gastric MMS in GERD subjects was significantly less than in non-GERD subjects. In non-GERD subjects, the gastric MMS moves rostrally into the distal esophagus during deglutitive inhibition and forms a barrier. This movement of the MMS is defective in patients with GERD.

Mechanisms of Postintervention and Nine-Month Luminal Enlargement After Treatment of Drug-Eluting In-Stent Restenosis With a Drug-Eluting Balloon

Using optical coherence tomography (OCT), the mechanisms of postintervention and 9-month luminal enlargement in drug-eluting stent in-stent restenosis (ISR) lesions treated with a drug-eluting balloon (DEB) were evaluated. A total of 42 patients with DEB-treated drug-eluting stent ISR lesions underwent serial OCT examination before intervention, after intervention, and at 9-month follow-up. Preintervention OCT-derived neointima was classified as either a homogeneous or nonhomogeneous pattern. Ten ISR lesions with homogeneous neointima were identified and compared with 32 ISR lesions with nonhomogeneous neointima. When comparing pre- and postintervention evaluations, changes in luminal cross-sectional area (CSA) were 3.4mm(2) in ISR lesions with homogeneous neointima and 3.7mm(2) in those with nonhomogeneous neointima, respectively (p= 0.529); changes in stent CSA were 2.5mm(2) and 1.4mm(2), respectively, p= 0.004; and changes in neointimal CSA were-0.9mm(2) and-2.3mm(2), respectively, p= 0.001. At 9-month follow-up, changes in luminal CSA were-2.0mm(2) and-0.9mm(2) in ISR lesions with homogeneous and nonhomogeneous neointima, respectively (p= 0.021); in stent CSA changed by-0.2mm(2) in both groups (p= 0.851) and changes in neointimal CSA was 1.8mm(2) and 0.7mm(2), respectively (p= 0.003). At the 9-month follow-up, >50% neointimal CSA stenosis was observed in 60% and 19% of the ISR lesions with homogeneous and nonhomogeneous neointima, respectively (p= 0.020). In conclusion, the mechanism of postintervention luminal enlargement by DEB varied with the preintervention OCT-based neointimal characteristics. ISR lesions with homogeneous neointima determined by OCT were associated with greater subsequent regrowth of neointima after DEB treatment.

Effect of hyperbaric oxygen therapy on cerebral vasospasm: a vascular morphometric study in an experimental subarachnoid hemorrhage model

This study was undertaken to investigate the preventive or therapeutic effect of hyperbaric oxygen therapy (HBOT) on cerebral vasospasm following experimental subarachnoid hemorrhage (SAH). Twenty rabbits were assigned randomly to one of four groups. Animals in Group I were not subjected to SAH or sham operation (control group, n = 5). Animals in Group II were subjected to sham operation and received no treatment after the procedure (sham group, n = 5). Animals in Group III were subjected to SAH and received no treatment after SAH induction (SAH group, n = 5). Animals in Group IV were subjected to SAH and received five sessions of HBOT at 2.4 atmospheres absolute (ATA) for 2 h (treatment group, n = 5). Animals were euthanized by perfusion and fixation 72 h after procedures. Basilar artery vasospasm indices, arterial wall thicknesses, and cross-sectional luminal areas were evaluated. Statistical comparisons were performed using Kruskal–Wallis and Mann–Whitney U tests. Mean basilar artery vasospasm index in the treatment group was significantly smaller than in the SAH group. Mean basilar artery wall thickness in the treatment group was significantly smaller than in the SAH group. Mean basilar artery cross-sectional luminal area in the treatment group showed an increase relative to the SAH group, but this difference remained statistically insignificant. Our results demonstrated that repeated application of HBOT at 2.4 ATA for 2 h attenuated vasospastic changes such as increased vasospasm index and arterial wall thickness. HBOT is thus a promising candidate for SAH-induced vasospasm. Further studies are needed to evaluate maximal effect and optimal application regimen.

Intimal hyperplasia following implantation of helical-centreline and straight-centreline stents in common carotid arteries in healthy pigs: influence of intraluminal flow †

Intimal hyperplasia (IH) is a leading cause of obstruction of vascular interventions, including arterial stents, bypass grafts and arteriovenous grafts and fistulae. Proposals to account for arterial stent-associated IH include wall damage, low wall shear stress (WSS), disturbed flow and, although not widely recognized, wall hypoxia. The common non-planarity of arterial geometry and flow, led us to develop a bare-metal, nitinol, self-expanding stent with three-dimensional helical-centreline geometry. This was deployed in one common carotid artery of healthy pigs, with a straight-centreline, but otherwise identical (conventional) stent deployed contralaterally. Both stent types deformed the arteries, but the helical-centreline device additionally deformed them helically and caused swirling of intraluminal flow. At sacrifice, one month post stent deployment, histology revealed significantly less IH in the helical-centreline than straight-centreline stented vessels. Medial cross-sectional area was not significantly different in helical-centreline than straight-centreline stented vessels. By contrast, luminal cross-sectional area was significantly larger in helical-centreline than straight-centreline stented vessels. Mechanisms considered to account for those results include enhanced intraluminal WSS and enhanced intraluminal blood-vessel wall mass transport, including of oxygen, in the helical-centreline stented vessels. Consistent with the latter proposal, adventitial microvessel density was lower in the helical-centreline stented than straight-centreline stented vessels.