Outcomes With the Use of Bag-Valve-Mask Ventilation During Out-of-hospital Cardiac Arrest in the Pragmatic Airway Resuscitation Trial.

BACKGROUND: While emergency medical services (EMS) often use endotracheal intubation (ETI) or supraglottic airways (SGA), some patients receive only bag-valve-mask (BVM) ventilation during out-of-hospital cardiac arrests (OHCA). Our objective was to compare patient characteristics and outcomes for BVM ventilation to advanced airway management (AAM) in adults with OHCA. METHODS: Using data from the Pragmatic Airway Resuscitation Trial, we identified patients receiving AAM (ETI or a SGA), BVM ventilation only (BVM-only), and BVM ventilation as a rescue after at least one failed attempt at advanced airway placement (BVM-rescue). The outcomes were return of spontaneous circulation (ROSC), 72-hour survival, survival to hospital discharge, neurologically intact survival (Modified Rankin Scale ≤ 3), and the presence of aspiration on a chest radiograph. Comparisons were made using generalized mixed-effects models while adjusting for age, sex, initial rhythm, EMS-witnessed status, bystander cardiopulmonary resuscitation, response time, study cluster, and advanced life support first on scene. RESULTS: Of 3,004 patients enrolled, there were 282 BVM-only, 2,129 AAM, and 156 BVM-rescue patients with complete covariates. Shockable initial rhythms (34% vs. 18.6%) and EMS-witnessed arrests (21.6% vs. 11.3%) were more likely in BVM-only than AAM but similar between BVM-rescue and AAM. Compared to AAM, BVM-only patients had similar ROSC (odds ratio [OR] = 1.29, 95% confidence interval [CI] = 0.96 to 1.73), but higher 72-hour survival (OR = 1.96, 95% CI = 1.42 to 2.69), survival to discharge (OR = 4.47, 95% CI = 3.03 to 6.59), and neurologically intact survival (OR = 7.05, 95% CI = 4.40 to 11.3). Compared to AAM, BVM-rescue patients had similar ROSC (OR = 0.73, 95% CI = 0.47 to 1.12) and 72-hour survival (OR = 1.08, 95% CI = 0.66 to 1.77) but higher survival to discharge (OR = 2.15, 95% CI = 1.17 to 3.95) and neurologically intact survival (OR = 2.64, 95% CI = 1.20 to 5.81). Aspiration incidence was similar. CONCLUSIONS: Bag-valve-mask-only ventilation is associated with improved OHCA outcomes. Despite similar rates of ROSC and 72-hour survival, BVM-rescue ventilation was associated with improved survival to discharge and neurologically intact survival compared to successful AAM.

Are the local blood oxygen level-dependent (BOLD) signals caused by neural stimulation response dependent on global BOLD signals induced by hypercapnia in the functional MR imaging experiment? Experiments of long-duration hypercapnia and multilevel carbon dioxide concentration.

BACKGROUND AND PURPOSE: The relationship between the local blood oxygen level-dependent (BOLD) signals caused by neural stimulation (fBOLD) and the global BOLD signals induced by hypercapnia (hBOLD) has not been fully investigated. In this study, we examine whether fBOLD is modulated by hBOLD signals, by means of experiments using a relatively wide range of inhaled carbon dioxide (CO(2)) for a long duration of 5 minutes. MATERIALS AND METHODS: Ten healthy volunteers were recruited, each undergoing 6 separate experiments by inhaling gas mixtures with different fractions of CO(2) (room air, 3%-7%). Each experiment contained 3 phases, prehypercapnic, hypercapnic, and posthypercapnic, during which boxcar visual stimulus was given. The local fBOLD signals were measured from areas showing activation patterns highly correlated with the visual stimulus paradigm, whereas the global hBOLD signals were measured from areas showing no visual activations. Percentage changes in fBOLD during transient-state hypercapnia and steady-state hypercapnia were both investigated in response to varying degrees of hypercapnic perturbations. RESULTS: The hBOLD signals increased with increase of inhaled CO(2) fractions. The duration for the hBOLD signals to reach steady state prolonged with increase of inhaled CO(2) fractions. Normalized fBOLD ratio was inversely related to the inhaled CO(2) during steady-state hypercapnia but showed positive association with hBOLD during transient-state hypercapnia. CONCLUSION: Our study concludes that the steady-state fBOLD signal intensity is dependent on and inversely related to the hBOLD signals. Previous reports documenting independent and additive relationships between hBOLD and fBOLD may likely be due to transient-state observations.

Evaluating Instantaneous Perfusion Responses of Parotid Glands to Gustatory Stimulation Using High-Temporal-Resolution Echo-Planar Diffusion-Weighted Imaging.

BACKGROUND AND PURPOSE: Parotid glands secrete and empty saliva into the oral cavity rapidly after gustatory stimulation. However, the role of the temporal resolution of DWI in investigating parotid gland function remains uncertain. Our aim was to design a high-temporal-resolution echo-planar DWI pulse sequence and to evaluate the instantaneous MR perfusion responses of the parotid glands to gustatory stimulation. MATERIALS AND METHODS: This prospective study enrolled 21 healthy volunteers (M/F = 2:1; mean age, 45.2 ± 12.9 years). All participants underwent echo-planar DWI (total scan time, 304 seconds; temporal resolution, 4 s/scan) on a 1.5T MR imaging scanner. T2WI (b = 0 s/mm2) and DWI (b = 200 s/mm2) were qualitatively assessed. Signal intensity of the parotid glands on T2WI, DWI, and ADC was quantitatively analyzed. One-way ANOVA with post hoc group comparisons with Bonferroni correction was used for statistical analysis. P < .05 was statistically significant. RESULTS: Almost perfect interobserver agreement was achieved (κ ≥ 0.656). The parotid glands had magnetic susceptibility artifacts in 14.3% (3 of 21) of volunteers during swallowing on DWI but were free from perceptible artifacts at the baseline and at the end of scans on all images. Increased ADC and reduced signal intensity of the parotid glands on T2WI and DWI occurred immediately after oral administration of lemon juice. Maximal signal change of ADC (24.8% ± 10.8%) was significantly higher than that of T2WI (-10.1% ± 5.2%, P < .001). The recovery ratio of ADC (100.71% ± 42.34%) was also significantly higher than that of T2WI (22.36% ± 15.54%, P < .001). CONCLUSIONS: Instantaneous parotid perfusion responses to gustatory stimulation can be quantified by ADC by using high-temporal-resolution echo-planar DWI.

Synovial chondroma of the ankle in a young child after recent trauma: CT and MR features.

We report a case of synovial chondroma of the left ankle in an 11-year-old boy presenting with soft tissue swelling after recent trauma. The noncalcified or nonossified intraarticular chondroma arising from metaplastic synovium has characteristic imaging appearance on computed tomography (CT) and magnetic resonance imaging (MRI). A lobulated mass of fluid-like density and signal intensity along with internal septa are characteristic features on CT and MRI. The knowledge of CT and MRI features of noncalcified or nonossified synovial chondroma is important to distinguish from the simple or complicated effusion, hemarthrosis, or other synovial process.

Imaging findings of intradiaphragmatic bronchogenic cyst: a case report.

Isolated intradiaphragmatic bronchogenic cysts are extremely rare. Here, we report a case of intradiaphragmatic bronchogenic cyst with calcifications in a 34-year-old man presenting with no clinical symptoms. Imaging studies of the chest, including chest roentgenogram and computerized tomography (CT), revealed a left posterior mediastinal mass that abutted onto the left diaphragmatic crus with multiple calcifications and showed no enhancement after contrast administration on CT. The patient underwent surgical resection of the mass. Intradiaphragmatic bronchogenic cyst with calcifications was diagnosed by pathology. The patient was discharged 10 days after the operation, and no complication was found 3 months later at follow-up.

Primitive neuroectodermal tumor of the kidney associated with Budd-Chiari syndrome in a 17-year-old girl.

Renal primitive neuroectodermal tumor (PNET) is a rare and highly malignant neoplasm of the kidney. We report the case of a 17-year-old girl with renal PNET that was complicated by Budd-Chiari syndrome. She was admitted due to abrupt left flank pain and gross hematuria. Abdominal sonography and computerized tomography (CT) disclosed a large hemorrhagic left renal mass and thrombus in the inferior vena cava (IVC). Left radical nephrectomy was performed and renal PNET with tumor rupture and tumor invasion into the IVC was diagnosed based on operative findings and histologic features. Tumor cells were positive for neuronspecific enolase, chromogranin-A, and vimentin but negative for cytokeratin, leukocyte common antigen, CD3, and CD20. The thrombus in the IVC extended into the right atrium and caused obstruction of the right and middle hepatic venous outflow, which was evident on follow-up CT scan 5 months later. The patient died due to hepatic failure and progressive cardiovascular compromise 6 months after surgery. This case demonstrates that renal PNET can be life threatening when the tumor thrombus extends into the IVC and causes hepatic outflow obstruction.

Subglottic hemangioma associated with cutaneous and cerebellar hemangiomas detected by MRI: report of one case.

Subglottic hemangioma (SGH) is a benign neoplasm that may cause severe and life-threatening respiratory obstruction in infants. However, patients usually present with inspiratory stridor in the first few months of life and may be mistakenly diagnosed as recurrent or persistent croup. Definitive diagnosis is made by image studies, endoscopic examination and biopsy or all. We report a 2-month-old female infant of SGH with initial clinical manifestations of dyspnea and inspiratory stridor co-existing with cutaneous and cerebellar hemangiomas. Clinicians must be alert the possibility of SGH when associated with cutaneous hemangioma. This patient has received oral steroid treatment for more than two months with improvement of the airway obstruction. Although purplish patch lesions over left side of face, eyelid, cheek, and peri-oral regions regressed, the size of the SGH on the followed MRI was slightly enlarged. The diagnosis and various treatments of SGH are discussed and reviewed in this paper.

Transition into driven equilibrium of the balanced steady-state free precession as an ultrafast multisection T2-weighted imaging of the brain.

BACKGROUND AND PURPOSE: Current T2-weighted imaging takes >3 minutes to perform, for which the ultrafast transition into driven equilibrium (TIDE) technique may be potentially helpful. This study qualitatively and quantitatively evaluates the imaging of transition into driven equilibrium of the balanced steady-state free precession (TIDE) compared with TSE and turbo gradient spin-echo on T2-weighted MR images. MATERIALS AND METHODS: Thirty healthy volunteers were examined with T2-weighted images by using TIDE, TSE, and turbo gradient spin-echo sequences. Imaging was evaluated qualitatively by 2 independent observers on the basis of a 4-point rating scale regarding contrast characteristics and artifacts behavior. Image SNR and contrast-to-noise ratio were quantitatively assessed. RESULTS: TIDE provided T2-weighted contrast similar to that in TSE and turbo gradient spin-echo with only one-eighth of the scan time. TIDE showed gray-white matter differentiation and iron-load sensitivity inferior that of TSE and turbo gradient spin-echo, but with improved motion artifacts reduction on qualitative scores. Nonmotion ghosting artifacts were uniquely found in TIDE images. The overall SNRs of TSE were 1.9-2.0 times those of turbo gradient spin-echo and 1.7-2.2 times of those of TIDE for brain tissue (P < .0001). TIDE had a higher contrast-to-noise ratio than TSE (P = .169) and turbo gradient spin-echo (P < .0001) regarding non-iron-containing gray matter versus white matter. TIDE had a lower contrast-to-noise ratio than turbo gradient spin-echo and TSE (P < .0001) between iron-containing gray matter and white matter. CONCLUSIONS: TIDE provides T2-weighted images with reduced scan times and reduced motion artifacts compared with TSE and turbo gradient spin-echo with the trade-off of reduced SNR and poorer gray-white matter differentiation.

CT Angiographic Diagnosis of a Ruptured Intraventricular Arteriovenous Malformation in a Teenager Playing a Video Game.

Intraventricular arteriovenous malformation (AVM) is a rare congenital vascular disorder that is often associated with primary intraventricular hemorrhage (IVH) and a rapid clinical course. Acute imaging diagnosis requires depiction of both the location of hemorrhage and vascular nidus for emergent management. In this report, a 17-year-old teenager developed primary IVH with presentation of consciousness change during a video game. Multidetector-row computed tomographic angiography (CTA) demonstrated an AVM in the right lateral ventricle and its angioarchitectural relationship to the surrounding intracranial structures. Although selective angiography is essential both in planning treatment for cerebral AVMs and in establishing the final diagnosis, CTA can be an important first-line imaging modality to quickly confirm the diagnosis and hence initiate prompt management.

Anomalous J-modulation effects on amino acids in clinical 3T MR spectroscopy.

The signal-intensity loss from anomalous J-modulation effects due to chemical-shift displacement was investigated on amino acid groups (alanine, valine, leucine, and isoleucine) at 3T by using point-resolved (1)H spectroscopy in patients with brain abscess and phantom experiments. With a larger chemical shift between methyl and methine resonances, alanine shows a greater effect of signal-intensity cancellation compared with other amino acids around 0.9 ppm, resulting in noninverted doublets at a TE of 144 ms.

Trousseau's syndrome related to adenocarcinoma of the colon and cholangiocarcinoma.

Malignancy-related thromboembolism, so-called Trousseau's syndrome, can present as acute cerebral infarction, non-bacterial thrombotic endocarditis (NBTE) and migratory thrombophlebitis. It is usually attributed to a cancer-related hypercoagulable state, chronic disseminated intravascular coagulopathy (DIC), or tumour embolism. We report on two patients with adenocarcinoma of the colon and cholangiocarcinoma who developed widespread thromboembolism during disease progression. Both did poorly despite aggressive institution of anticoagulation therapy. These cases emphasize that cerebral infarction or refractory thromboembolism in cancer-treated patients should prompt investigation for recurrent or metastatic disease or progression of the underlying malignancy. Optimal treatment remains to be established.

Primary hemangiopericytoma of the tibia: MR and angiographic correlation.

The Magnetic Resonance Imaging (MRI) appearances of primary osseous hemangiopericytoma (HPC) have been rarely described. We report on a 46-year-old Chinese man with primary osseous HPC of the right tibia. The characteristic vascular distribution of this tumor, presenting with a "spoke-wheel" appearance on MR images and with angiographic correlation, is described. Although not pathognomonic, this MR appearance may be an important finding in suggesting the diagnosis of osseous HPC.

Ganglion cysts of the cruciate ligaments.

PURPOSE: To evaluate the MR findings of ganglion cysts of the cruciate ligaments in correlation with clinical findings. MATERIAL AND METHODS: We reviewed 12 patients with ganglion cysts of the cruciate ligaments obtained from a medical record of 4153 consecutive patients referred for knee MR examinations. All patients presented with chronic knee pain and 4 had restriction of knee motion. The MR imaging findings of the cysts were evaluated and correlated with clinical manifestations. RESULTS: Seven ganglion cysts were found in the posterior cruciate ligaments and 5 in the anterior cruciate ligaments. All cysts were lobulated (n=7) or fusiform (n=5) in shape, 1.8-4.5 cm in size, along the posterior surface in the proximal or distal end of the ligaments. Ten patients had arthroscopic resection or aspiration of their cysts, became symptom free and had no recurrence on follow-up MR examinations. Two cysts reduced in size spontaneously by conservative treatment. CONCLUSION: MR imaging can offer useful information in detection and diagnosis of patients with chronic knee pain due to ganglion cysts of the cruciate ligaments. The size and location of the ganglion cysts can attribute to the clinical manifestations.