Ultrasound Imaging

Resumen En esta segunda parte se aborda de manera específica la patología del parénquima
pulmonar. El tema está estructurado en diferentes partes que incluyen el estudio de las atelectasias,
la neumonía y los abscesos, el patrón de infiltración intersticial y/o alveolar o patrón
de líneas B, y finalmente se analiza el tromboembolismo pulmonar. Con esta segunda parte del
texto hemos ofrecido los conocimientos básicos necesarios para realizar ecografías pulmonares
en un servicio de anestesia.

The use of diagnostic ultrasound by physiotherapists is not a new concept; it is frequently performed in musculoskeletal physiotherapy. Physiotherapists currently lack accurate, reliable, sensitive and valid measurements for the assessment of the indications and effectiveness of chest physiotherapy. Thoracic ultrasound may be a promising tool for the physiotherapist and could be routinely performed at patients’ bedsides to provide real-time and accurate information on the status of pleura, lungs and diaphragm; this would allow assessment of lung aeration from interstitial syndrome to lung consolidation with much better accuracy than chest X-rays or auscultation. Diaphragm excursion and contractility may also be assessed by ultrasound. This narrative review refers to lung and diaphragm ultrasound semiology and describes how physiotherapists could use this tool in their clinical decision-making processes in various cases of respiratory disorders. The use of thoracic ultrasound semiology alongside typical examinations may allow for the guiding, monitoring and evaluating of chest physiotherapy treatments. Thoracic ultrasound is a potential new tool for physiotherapists.

This study explores the phenomenon of uvularization in the vowel systems of two Heishui County varieties of Qiang, a Sino-Tibetan language of Sichuan Province, China. Ultrasound imaging (one speaker) shows that uvularized vowels have two tongue gestures: a rearward gesture, followed by movement toward the place of articulation of the corresponding plain vowel. Time-aligned acoustic and articulatory data show how movement toward the uvula affects the acoustic signal. Acoustic correlates of uvularization (taken from two speakers) are seen most consistently in raising of vowel F1, lowering of F2 and in raising of the difference F3-F2. Imaging data and the formant structure of [l] show that uvular approximation can begin during the initial consonant that precedes a uvularized vowel. Uvularization is reflected phonologically in the phonotactic properties of vowels, while vowel harmony aids in the identification of plain-uvularized vowel pairs. The data reported in this paper argue in favor of a revision of the catalog of secondary articulations recognized by the International Phonetic Alphabet, in order to include uvularization, which can be marked with the symbol [ʶ] in the case of approximation and [χ] for secondary uvular frication.

This paper presents a novel indoor navigation technique using acoustic sensors, with emphasis on performance modeling and the system layout. Acoustic transmitters are arranged at known fixed locations and broadcast their respective signals following a Time Division Multiple Access (TDMA) scheme. The receiver position is calculated based on Time of Arrival (TOA) based ranging measurements from a minimum of four transmitters. The transmitters are arranged optimally to minimize Position Dilution of Precision (PDOP) as well as maximizing sensor availability. The proposed technique can provide accurate navigation observables in indoor environments, where conventional satellite-based navigation systems cannot deliver the required Position, Velocity, and Time (PVT) data. Additionally, being based on acoustic signals, it is immune to signal-in-space electromagnetic interferences. The TDMA based acoustic navigation system is described, with potential errors in ranging due to Doppler effect, multipath, atmospheric propagation, and signal delays. The error in positioning due to platform dynamics is also discussed. This analysis will lead to an optimized arrangement of transmitters supporting the future ground and flight experimental activities.

In the first years of life, children differ greatly from adults in the temporal organization of their speech gestures in fluent language production. However, dissent remains as to the maturational direction of such organization. The present study sheds new light on this process by tracking the development of anticipatory vowel-to-vowel coarticulation in a cross-sectional investigation of 62 German children (from 3.5 to 7 years of age) and 13 adults. It focuses on gestures of the tongue, a complex organ whose spatiotemporal control is indispensable for speech production. The goal of the study was threefold: 1) investigate whether children as well as adults initiate the articulation for a target vowel in advance of its acoustic onset, 2) test if the identity of the intervocalic consonant matters and finally, 3) describe age-related developments of these lingual coarticulatory patterns. To achieve this goal, ultrasound tongue imaging was used to record lingual movements and quantify changes in coarticulation degree as a function of consonantal context and age. Results from linear mixed effects models indicate that like adults, children initiate vowels' lingual gestures well ahead of their acoustic onset. Second, while the identity of the intervocalic consonant affects the degree of vocalic anticipation in adults, it does not in children at any age. Finally, the degree of vowel-to-vowel coarticulation is significantly higher in all cohorts of children than in adults. However, among children, a developmental decrease of vocalic coarticulation is only found for sequences including the alveolar stop /d/ which requires finer spatiotemporal coordination of the tongue's subparts compared to labial and velar stops. Altogether, results suggest greater gestural overlap in child than in adult speech and support the view of a non-uniform and protracted maturation of lingual coarticulation calling for thorough considerations of the articulatory intricacies from which subtle developmental differences may originate.

Purpose. With anomalous insertion of the pectoralis minor muscle, its distal fibers pass over the coracoid process instead
of inserting on it, following sometimes a trajectory very similar to that of the coracohumeral ligament. The aim of this prospective
study was to evaluate the frequency of detection of this anomalous insertion by ultrasonography.
Materials and Methods. Ultrasound demonstrated the abnormal insertion of the pectoralis minor muscle by directly visualizing
its fibers slipping over the coracoid process during external and internal rotation of the humerus. Three hundred and
three individuals underwent ultrasound of the shoulders (64,7% female, mean age of 45 years), for a total of six hundred
and six shoulders; 30% (183/606) were symptomatic.
Results. An abnormal insertion was demonstrated in 9,57% of the examined shoulders (58/606), with a statistically significant
predominance on the left side (12,2%) compared to the right side (6,9%), and of women (12,2%) compared to men
(4,7%).
Conclusion. Ultrasound demonstrated an abnormal insertion of the pectoralis minor muscle in 9,57% of 606 examined
shoulders. There was a female and left side predominance and no significant correlation with symptoms.

Objective: To determine
the accessibility of the coracohumeral
ligament (CHL) by ultrasound (US)
and to determine CHL thickness in
adhesive capsulitis of the shoulder.
Design and patients: US examinations
were carried out in 498 consecutive
shoulders of 306 individuals
(194 women and 112 men), mean age
47.4 years (range 15–92 years), in
order to identify and measure the
maximum thickness of the CHL. The
patients were divided into three study
groups: asymptomatic shoulders
(n=121), painful shoulders (n=360)
and shoulders with arthrographic evidence
of adhesive capsulitis (n=17).
The mean maximal thickness of CHL
was compared among the 3 study
groups (non-parametric test of
Kruskal–Wallis, p<0.05). Results:
The CHL was visualized in 92 out of
121 shoulders in the asymptomatic
group (76.0%), in 227 out of 360
shoulders in the painful shoulder
group (63.0%), and in 15 out of 17
shoulders in the adhesive capsulitis
group (88.2%). The average thickness
of the CHL was significantly greater
in adhesive capsulitis (3 mm) than in
the asymptomatic (1.34 mm) and
painful (1.39 mm) shoulders. No
significant difference was found
between asymptomatic and painful
shoulders. Conclusion: CHL depiction
can be achieved in a reasonable
proportion of shoulders. A thickened
CHL is suggestive of adhesive
capsulitis. More studies are needed
for clinical validation of these data.

SUMMARY
Introduction: Pulmonary involvement is the most frequent complication of SARS-CoV-2 infection (COVID-
19).
Objectives: Describe the utility of early computed tomography (CT) scan of thorax in the management and detection of pulmonary parenchyma compromise.
Material and methods: Eighty (80) patients with COVID-19 pneumonia (confirmed by RT-PCR detection
of SARS-Cov-2 in nasopharyngeal swabs) who were admitted to the Unit 17th,, “B” Division, Infectious Diseases F. J. Muñiz Reference Hospital, CABA, and who underwent early chest CT scans were retrospectively
enrolled. Imaging features, predominant radiological lung patterns, and distribution were retrospectively
analyzed.
Results: 80 patients admitted to the hospital between June 2020 to August 2020, were retrospectively enrolled. The cohort included 80 (100%) men with a mean age of 45.5 years (range 21 to 81 years). The predominant pattern of abnormality observed was ground-glass opacification (33 [41.3%] patients), bilateral compromise (71 [93.4%] patients), multilobar involvement (71 [93.4%] patients) and subpleural lesions (peripheral) (38 [57.6%] cases).
Conclusion: Bilateral, diffuse, ground-glass opacities were the predominance findings on early CT thorax scan of confirmed COVID-19 pneumonia. Consolidation and mixed patterns were also frequent. COVID-19 pneumonia presents with chest CT imaging abnormalities in the majority of patient even in early stages of the disease.
RESUMEN
Introducción: El compromiso pulmonar es la complicación más frecuente de la infección por SARS-CoV-2 (COVID-19).
Objetivos: Describir la utilidad de la tomografía computarizada (TC) de tórax realizada tempranamente para la detección y evaluación del compromiso pulmonar en la enfermedad COVID-19.
Materiales y métodos: Se analizaron de manera retrospectiva ochenta (80) pacientes con diagnóstico confirmado (RT-PCR en hisopados nasofaríngeos con detección de SARS-Cov-2) de neumonía por COVID-19 internados en la Unidad 17, División “B”, del Hospital de Referencia
en Enfermedades Infecciosas F.J.Muñiz, CABA, a los que se les efectuó TC de tórax en las primeras 24 horas de su ingreso hospitalario. Se analizaron de manera retrospectiva y descriptiva los patrones radiológicos de compromiso pulmonar más frecuentes, su localización
y distribución.
Resultados: se incluyeron en la evaluación, 80 pacientes internados en el Hospital entre los meses de Junio y Agosto de 2020. Todos (100%) fueron varones con una mediana de edad de 45.5 años (rango 21 a 81 años). El patrón radiológico predominante en la TC fueron las opacidades en vidrio esmerilado (33 [41.3%] de los pacientes); con predominio del compromiso bilateral (71 [93.4%] pacientes), multilobar (71 [93.4%] pacientes) y localización subpleural (periférica) (38 [57.6%] casos).
Conclusión: Las opacidades en vidrio esmerilado, bilaterales, difusas y de predominio subpleural en su localización fueron los hallazgos más comunes en la TC de tórax efectuada de forma precoz en pacientes con diagnóstico de neumonía por COVID-19. Las imágenes de consolidación
y los patrones mixtos también fueron hallazgos frecuentes en la TC de tórax observados en la mayoría de los pacientes, aún en estadios tempranos de la enfermedad por COVID-19.

Doppler signals collected with a focused transducer are known to be affected by the so-called intrinsic spectral broadening (ISB). This article aims to point out how ISB is, in general, related to both the limited lateral extent of a focused beam (leading to a finite transit time), and the presence of several local insonation angles around the beam axis, due to focusing and diffraction effects (local geometrical broadening). The influence of
these two elementary spectral contributions on the whole ISB is shown by considering the Doppler signal as simultaneously modulated in amplitude and frequency, and applying well-known relationships employed in the communication field. Such an analysis reveals that transit time and local geometrical broadening are two different phenomena, whose simultaneous knowledge is necessary for correctly evaluating the overall ISB.
Finally, thanks to a novel technique for separately measuring transit time and local geometrical broadening effects on transducers with markedly different focusing properties, more than 1000 experimental acquisitions show how a proper combination of such measured contributions gives an accurate ISB estimation, confirming the theoretical expectations.