Mechanism of mosaic attenuation of the lungs  on computed tomography in induced bronchospasm

The purpose of this study was to investigate whether hypoxic pulmonary vasoconstriction is the major determinant of the computed tomography (CT) pattern of mosaic attenuation in asthmatic patients with induced bronchoconstriction. Thin-section CT was performed at suspended full inspiration immediately and 30 min after methacholine bronchoprovocation in 22 asthmatic subjects, who were randomly assigned to breathe room air ( group A, n = 8), oxygen via nasal prongs at 5 l/min ( group B, n = 8), and oxygen via face mask at 12 l/min ( group C, n = 6). CT changes were quantified in terms of global lung density and density in hypodense and hyperdense areas. Lung parenchymal density increases were greatest in group C and greater in group B than in group A, globally ( P = 0.03) and in hypodense regions ( P = 0.01). On bivariate analysis, the only change in cross-sectional area was related to change in global density. In hypodense regions, density change was related both to reduction in cross-sectional area ( P < 0.0005) and to oxygen administration ( P = 0.01). After correction for changes in global lung density, only oxygen was independently related to density increase in hypodense areas ( P = 0.02). In induced bronchoconstriction, the CT appearance of mosaic attenuation can be largely ascribed to hypoxic vasoconstriction rather than to changes in lung inflation.

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Contralateral C7 Transfer to Axillary and Median Nerves in Rats with Total Brachial Plexus Avulsion

10.21203/rs.2.20612/v2 ◽

2020 ◽

Author(s):

Yuzhou Liu ◽

Feng Xiao ◽

Yongqing Zhuang ◽

Jie Lao

Keyword(s):

Brachial Plexus ◽

Median Nerve ◽

Axillary Nerve ◽

Cross Sectional Area ◽

Sectional Area ◽

Behavioral Test ◽

Cross Sectional ◽

Group A ◽

Group B ◽

Group D

Abstract Background: Contralateral cervical 7 nerve (cC7) was used to repair two recipient nerves simultaneously for patients with total brachial plexus avulsion (TBPA). Objective: To evaluate the effect of cC7 transfer to axillary and median nerves in rats with TBPA. Methods: Eighty S-D rats were divided into 4 groups randomly on average. Group A: cC7 － median nerve, Group B: cC7 － axillary nerve, Group C: cC7 － median and axillary nerves, Group D: TBPA without repair. The evaluation tools included behavioral test, electromyogram (EMG), cross-sectional area of muscle fiber, nerve fiber count and gene expression. Results: The effective rates of EMG were 90% and 70% in Flexor Carpi Radialis (FCR) in Group A and C, while 70% and 60% in deltoid (DEL) in Group B and C. In behavioral test, the difference of effective rates between groups was not significant. The mean cross-sectional area of FCR in Group A or C was significantly larger than that in Group D. Either the number of median or axillary nerve fibers in Group A, B or C was statistically more than that in Group D. No matter for FCR or DEL, there were no significant differences in the ratios of relative expression of Muscle Atrophy F-box （ MAFBOX ） and Muscle RING Finger 1 （ MURF1 ） among these groups. Conclusion: Compared with cC7 transfer to median nerve, cC7 transfer to both median and axillary nerves did not affect median nerve recovery. The deltoid muscle also could be restored. The recovery proportion of axillary nerve was less than that of median nerve.

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Comparison of cross-sectional area and fat infiltration of suboccipital muscles between normal dogs and dogs with atlantoaxial instability

10.21203/rs.3.rs-930150/v1 ◽

2021 ◽

Author(s):

Namsoon Lee ◽

Munsu Yun ◽

Junghee Yoon

Keyword(s):

Quantitative Information ◽

Cross Sectional Area ◽

Neurological Symptoms ◽

Atlantoaxial Instability ◽

Sectional Area ◽

Large Area ◽

Cross Sectional ◽

Fat Infiltration ◽

Group A ◽

Group B

Abstract Background Atlantoaxial instability (AAI) is primarily a congenital neurological disorder affecting young toy-breed dogs. So far, most studies have focused on bones and ligaments related to AAI, and there are no studies on the suboccipital muscles (SOMs) that occupy a large area from the occipital bone to C2 in dogs. This study evaluated the cross-sectional area (CSA) and fat infiltration of the SOMs using magnetic resonance imaging (MRI), specifically, T1-weighted images, in normal dogs (≤ 5 kg) and AAI dogs. The relationship between the severity of the neurological symptoms of AAI (group A and group B) and the values from MRI was also assessed. Results AAI dogs had significantly smaller CSA (P = 0.029) and greater fat infiltration (P = 0.044) of the SOMs compared to normal dogs. AAI dogs with mild neurological symptoms for a long period (group A) had greater fat infiltration than AAI dogs with severe neurological symptoms (group B) (P = 0.035). Conclusions The muscle changes are most likely due to spinal cord compression resulting from instability; however, the possibility that chronic changes of the muscle may play an additional role in maintaining stability in this region cannot be excluded. This study provides fundamental quantitative information of the SOMs in normal and AAI dogs.

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Contralateral C7 Transfer to Axillary and Median Nerves in Rats with Total Brachial Plexus Avulsion

10.21203/rs.2.20612/v3 ◽

2020 ◽

Author(s):

Yuzhou Liu ◽

Feng Xiao ◽

Yongqing Zhuang ◽

jie lao

Keyword(s):

Brachial Plexus ◽

Median Nerve ◽

Axillary Nerve ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional ◽

Brachial Plexus Avulsion ◽

Group A ◽

Group B ◽

Group D

Abstract Background: Contralateral cervical 7 nerve (cC7) was used to repair two recipient nerves simultaneously for patients with total brachial plexus avulsion (TBPA). Objective: To evaluate the effect of cC7 transfer to axillary and median nerves in rats with TBPA. Methods: Eighty S-D rats were divided into 4 groups randomly on average. Group A: cC7 － median nerve, Group B: cC7 － axillary nerve, Group C: cC7 － median and axillary nerves, Group D: TBPA without repair. The evaluation tools included behavioral tests, electromyogram (EMG), measurement of cross-sectional area of muscle fiber, nerve fiber count and gene expression assay. Results: The effective rates of EMG were 90% and 70% in Flexor Carpi Radialis (FCR) in Group A and C, while 70% and 60% in deltoid (DEL) in Group B and C, respectively. In behavioral test, the differences of effective rates between groups were not significant. The mean cross-sectional area of FCR in Group A or C was significantly larger than that in Group D. Either the number of median or axillary nerve fibers in Group A, B or C was statistically more than that in Group D. No matter for FCR or DEL, there were no significant differences in the ratios of relative expression of Muscle Atrophy F-box （ MAFBOX ） and Muscle RING Finger 1 （ MURF1 ） among these groups. Conclusion: Compared with cC7 transfer to median nerve, cC7 transfer to both median and axillary nerves did not affect median nerve recovery. The deltoid muscle also could be restored. The recovery proportion of axillary nerve was less than that of median nerve.

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Contralateral C7 Transfer to Axillary and Median Nerves in Rats with Total Brachial Plexus Avulsion

10.21203/rs.2.20612/v1 ◽

2020 ◽

Author(s):

Yuzhou Liu ◽

Feng Xiao ◽

Yongqing Zhuang ◽

Jie Lao

Keyword(s):

Brachial Plexus ◽

Median Nerve ◽

Axillary Nerve ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional ◽

Brachial Plexus Avulsion ◽

Group A ◽

Group B ◽

Group D

Abstract Background: Contralateral cervical 7 nerve (cC7) was used to repair two recipient nerves simultaneously for patients with total brachial plexus avulsion (TBPA). Objective: To evaluate the effect of cC7 transfer to axillary and median nerves in rats with TBPA. Methods: Eighty S-D rats were divided into 4 groups averagely. Group A: cC7 － median nerve, Group B: cC7 － axillary nerve, Group C: cC7 － median and axillary nerves, Group D: TBPA without repair. The evaluation tools included behavioral test, electromyogram (EMG), cross-sectional area of muscle fiber, nerve fiber count and gene expression. Results: The positive rates of EMG were 90% and 70% in Flexor Carpi Radialis (FCR) in Group A and C, while 70% and 60% in deltoid (DEL) In Group B and C. The difference of effective rates in grip or shoulder abduction between groups was not significant. The mean cross-sectional area of FCR in Group A or C was significantly larger than that in Group D. Either the number of median or axillary nerve fibers in Group A, B or C was statistically more than that in Group D. No matter for FCR or DEL, there were no significant differences of the ratios of relative expression of MAFBOX and MURF1 among these groups. Conclusion: Compared with cC7 transfer to median nerve, cC7 transfer to both median and axillary nerves did not affect median nerve recovery and the deltoid muscle also could be restored. The recovery proportion of axillary nerve was less than that of median nerve.

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Influence of Lung Inflation on the Cross-Sectional Area of Central Airways in Normals and in Patients with Lung Disease

Respiration ◽

10.1159/000194372 ◽

1981 ◽

Vol 41 (3) ◽

pp. 145-154 ◽

Cited By ~ 13

Author(s):

Horst Baier ◽

Stephen Zarzecki ◽

Adam Wanner

Keyword(s):

Lung Disease ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional ◽

Lung Inflation ◽

The Cross

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Quantitative computed tomography measurement of cross-sectional area of small pulmonary vessels in asthmatic patients

Chinese Medical Journal ◽

10.1097/cm9.0000000000000367 ◽

2019 ◽

Vol 132 (16) ◽

pp. 1903-1908

Author(s):

Juan Wang ◽

Mei-Jiao Li ◽

Chun Chang

Keyword(s):

Computed Tomography ◽

Quantitative Computed Tomography ◽

Cross Sectional Area ◽

Sectional Area ◽

Cross Sectional ◽

Pulmonary Vessels ◽

Asthmatic Patients

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A clinical prediction rule to identify difficult intubation in children with Robin sequence requiring mandibular distraction osteogenesis based on craniofacial CT measures

BMC Anesthesiology ◽

10.1186/s12871-019-0889-1 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Zhe Mao ◽

Na Zhang ◽

Yingqiu Cui

Keyword(s):

Computed Tomography ◽

Retrospective Study ◽

Difficult Intubation ◽

Prediction Rule ◽

Clinical Prediction Rule ◽

Cross Sectional Area ◽

Sectional Area ◽

Clinical Prediction ◽

Cross Sectional ◽

Mandibular Distraction Osteogenesis

Abstract Background Airway management is challenging in children with Robin sequence (RS) requiring mandibular distraction osteogenesis (MDO). We derived and validated a prediction rule to identify difficult intubation before MDO for children with RS based on craniofacial computed tomography (CT) images. Method This was a retrospective study of 69 children with RS requiring MDO from November 2016 to June 2018. Multiple CT imaging parameters and baseline characteristic (sex, age, gestational age, body mass index [BMI]) were compared between children with normal and difficult intubation according to Cormack−Lehane classification. A clinical prediction rule was established to identify difficult intubation using group differences in CT parameters (eleven distances, six angles, one section cross-sectional area, and three segment volumes) and clinicodemographic characteristics. Predictive accuracy was evaluated by receiver operating characteristic (ROC) curve analysis. Results The overall incidence of difficult intubation was 56.52%, and there was no significant difference in sex ratio, age, weight, height, BMI, or gestational age between groups. The distance between the root of the tongue and posterior pharyngeal wall was significantly shorter, the bilateral mandibular angle shallower, and the cross-sectional area at the epiglottis tip smaller in the difficult intubation group. A clinical prediction rule based on airway cross-sectional area at the tip of the epiglottis was established. Area > 36.97 mm2 predicted difficult intubation while area < 36.97 mm2 predicted normal intubation with 100% sensitivity, 62.5% specificity, 78.6% positive predictive value, and 100% negative predictive value (area under the ROC curve = 0.8125). Conclusion Computed tomography measures can objectively evaluate upper airway morphology in patients with RS for prediction of difficult intubation. If validated in a larger series, the measures identified could be incorporated into airway assessment tools to guide treatment decisions. This was a retrospective study and was granted permission to access and use these medical records by the ethics committee of Guangzhou Women and Children’s Medical Center. Trials registration Registration No. ChiCTR1800018252, NaZhang, Sept 7 2018.

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