Chest Surfaces Research Articles

Radar-based remote physiological sensing: Progress, challenges, and opportunities.

Modern microwave Doppler radar-based physiological sensing is playing an important role in healthcare applications and during the last decade, there has been a significant advancement in this non-contact respiration sensing technology. The advantages of contactless, unobtrusive respiration monitoring have drawn interest in various medical applications such as sleep apnea, sudden infant death syndromes (SIDS), remote respiratory monitoring of burn victims, and COVID patients. This paper provides a perspective on recent advances in biomedical and healthcare applications of Doppler radar that can detect the tiny movement of the chest surfaces to extract heartbeat and respiration and its associated different vital signs parameters (tidal volume, heart rate variability (HRV), and so on) of the human subject. Additionally, it also highlights the challenges, and opportunities of this remote physiological sensing technology and several future research directions will be laid out to deploy this sensor technology in our day-to-day life.

11. An unusual case of dermatomyositis with anti-small ubiquitin-like modifier activating enzyme (SAE) antibodies present

IntroductionIdiopathic inflammatory myopathies (IIM) have long been diagnosed using a defined number of clinical criteria (Bohan and Peter). The emergence of new myositis specific antibodies (MSAs) and their relation to specific disease phenotypes may be useful in establishing a new clinical-serological diagnostic criteria for different disease presentations and thus help to determine management and prognosis. We present a case of dermatomyositis (DM) where limb subcutaneous oedema; a rare manifestation of the disease, and severe dysphagia were prominent clinical features in addition with the presence of anti-small ubiquitin-like modifier activating enzyme (SAE) antibodies.Case descriptionA 63-year-old Pakistani male presented with weight loss, anorexia, odynophagia, and a rash over his scalp, chest, face and flexor surfaces. Initial blood results revealed hypoalbuminaemia, CRP 7mg/L and ESR 37mm/h. A CT chest revealed an anterior mediastinum soft tissue mass suggestive of necrosis, with multiple ill-defined nodes throughout the lungs.An endoscopy revealed severe gastritis. Oropharyngeal examination revealed pooling of saliva and mucositis. Ceftriaxone was commenced for a presumed infective aetiology.Video fluoroscopy confirmed pharyngeal dysphagia with aspiration. Examination demonstrated a non-fatigable bulbar sounding dysarthria. There was no tongue wasting or fasciculations. Power was globally reduced, with marked proximal upper and lower limb weakness.Nerve conduction studies revealed normal sensation, and most motor nerves had normal conduction velocities with small nerve responses. Electromyography showed areas with denervation.With no improvement in the patient’s condition, anti-tuberculosis and anti-fungal therapy were commenced, with pulsed methylprednisolone for three days followed by 80mg daily to cover for an organizing pneumonia. Subsequent cultures were negative.Progressive weight loss with muscle wasting ensued and later, facial hyperpigmentation was noted in addition to the development of facial, lip and arms swelling. He was rheumatoid factor positive >500 iu/ml, with a raised IgE 2912 g/L and IgG 37.6 g/L. A CT-PET scan revealed intense uptake in the muscles posterior of the neck, tongue and masticators.An MRI scan of his arms revealed several abnormal signals around the shoulder girdle, long muscles of the back, and upper arm, which guided the site for muscle biopsy. This revealed highly abnormal skeletal muscle with frequent atrophic and necrotic fibres overrun by macrophages and T-cell rich inflammation. These findings in addition to serology reporting the presence of anti-SAE antibodies confirmed the diagnosis.Pulsed methylprednisolone, immunoglobulin therapy, and azathioprine were initiated with reducing prednisolone dose.DiscussionThis case of DM with a generalised rash, severe dysphagia and limb subcutaneous oedema were salient features in addition to the presence of anti-SAE antibodies. Anti-SAE has been shown to be present exclusively in DM patients where rash and severe dysphagia are common clinical findings. Our patient presented with severe dysphagia, which can be difficult to manage requiring enteral feeding. Video fluoroscopy was particularly useful in this case helping to stratify the severity of dysphagia and we would urge other clinicians to use this tool when investigating patients with suspected dermatomyositis to avoid potential complications of poor swallow including aspiration pneumonia. The additional imaging modality of PET-CT in our case confirmed the involvement of the muscles of mastication thus could prove a useful tool when investigating involvement of swallowing muscles in patients with anti-SAE DM.Skin features are another common finding in the anti-SAE group and our patient had a heliotrophic rash and shawl sign, which responded poorly to treatment. We describe the additional feature of severe subcutaneous limb and facial oedema, a rare manifestation of the disease, described in only a few other cases. Limb subcutaneous oedema is thought to reflect underlying severe muscle disease, is difficult to treat, and often is unresponsive to conventional treatment. Our case, and several other cases with the presence of limb oedema as reported in a literature search, required treatment with intravenous immunoglobulin and glucocorticoids, in addition with azathioprine and methotrexate.This is the first reported case to our knowledge of a patient with positive ANA, RF, anti-ccp, and anti-small ubiquitin-like modifier activating enzyme (anti-SAE) antibodies.Key learning pointsThe finding of anti-SAE in our case where severe dysphagia was present provides further weight to this antibody being a useful serological marker to identify this subgroup of DM patients. Identifying this antibody may be helpful in creating management strategies for these patients and determining disease progression and prognosis.The presence of limb and facial oedema may be an overlying feature of the anti-SAE group; however, previous cases of limb oedema have not identified this antibody as the SAE test was unavailable. The presence of severe dysphagia and subcutaneous oedema suggests the presence of anti-SAE lends itself to a clinical phenotype of DM that is particularly severe and requires multidisciplinary input.Conflicts of interestThe authors have declared no conflicts of interest.

Anti-TNF Alpha-Induced Psoriasis: A Rare Paradoxical Side Effect

Introduction: TNF-α inhibitors are widely used in the management of Crohn's disease (CD) and psoriasis. These agents can paradoxically cause psoriasis. We present a case report of Crohn's disease patient on infliximab therapy who developed psoriasis. Case report: A 45 year old man with a history of Crohn's colitis, well controlled on infliximab, came to clinic for evaluation of pruritic rash for 2-3 weeks that started on his legs initially and spread to involve his arms, chest, and back. He denied systemic symptoms, use of new medications or skin products, sick contact and recent travel. His CD was in remission for more than 1 year, and the last dose of infliximab was given 4 weeks ago. Skin exam revealed well-demarcated, erythematous plaques with overlying adherent scales involving chest, abdomen, back, legs and extensor surfaces of both arms. The patient was referred to dermatology for further evaluation. Punch skin biopsy revealed psoriasis. It was attributed to the use of infliximab. He was treated with topical steroids and UVB phototherapy with minimal improvement. Infliximab was held and planned to switch to other biologic agents for maintenance of CD. Discussion: CD is characterized by transmural inflammation of the gastrointestinal tract due to inflammatory cytokines such as interleukin (IL)-12 and TNF-α, resulting in symptoms of CD. TNF-α inhibitors, e.g., infliximab are effective in inducing and maintaining remission in moderate to severe CD patients. Plaque-type psoriasis, guttate psoriasis, palmoplantar pustulosis, psoriasis of the nail and scalp have been described in the literature with the use of these agents. Estimated prevalence is 0.6% to 5.3%. Previously reported cases have a wide diversity as far as agent types, gender and age of patients, treatment duration, type of eruption, and presence or absence of personal or family history of psoriasis are concerned. Pustular eruption resembling palmoplantar pustulosis is the most characteristic pattern, and it has been reported in about one-third of all reported cases. Pathogenesis of TNF-α inhibitors induced psoriasis involves a disruption in cytokine balance allowing unopposed interferon-α production by dendritic cells. In most cases, topical steroid therapy is enough. UVB phototherapy or discontinuation of TNF-α inhibitor or switching to an alternative anti-TNF agent is required in severe cases.Figure: Rash on back.Figure: Rash on elbow.

Three new species of Pristimantis (Amphibia, Anura, Craugastoridae) from upper montane forests and high Andean grasslands of the Pui Pui Protected Forest in central Peru

We describe three new species of Pristimantis from the upper montane forests and high Andean grasslands of the Pui Pui Protected Forest and its close surroundings (Región Junín, central Peru) and compare them morphologically and genetically with other taxonomically and biogeographically relevant species of Pristimantis. All three new species have the skin on dorsum shagreen with scattered tubercles, discontinuous dorsolateral folds, tuberculate flanks, and the skin on venter areolate. Pristimantis bounides sp. nov. is known from two localities outside the Pui Pui Protected Forest in upper montane forests between 3350 and 3463 m a.s.l. and is characterized by a snout–vent length of 18.2–21.0 mm in males (n = 3), and 21.6–24.4 mm in females (n = 4), by having a tympanum, males with vocal slits, and discs of digits slightly expanded with circumferential grooves. In life, dorsal and lateral ground coloration is pale grayish brown, orange brown, yellowish brown or reddish brown with dark grayish-brown marmorations, and a pale gray, pale greenish gray or creamish white venter with or without dark gray mottling. Pristimantis humboldti sp. nov. is known from one locality inside the Pui Pui Protected Forest, in upper montane forest at 3318 m a.s.l., and is characterized by a snout–vent length of 17.2–20.6 mm in males (n = 3), and 19.7–25.7 mm in females (n = 6), by having a tympanum, males with vocal slits, and discs of digits expanded with circumferential grooves. In life, dorsal and lateral ground coloration is orange brown with brownish-olive blotches, orange brown with grayish-brown blotches and flecks, reddish brown with grayish-brown blotches or grayish brown with orange brown blotches; throat, chest, belly, anterior and ventral surfaces of thighs, tibia, and axilla are dark gray and pale gray mottled with white and pale gray spots of different sizes and density. Pristimantis puipui sp. nov. is known from one locality inside the Pui Pui Protected Forest, in the puna at 3890 m a.s.l., and is characterized by a snout–vent length of 16.1–17.1 mm in males (n = 3), and 20.6–22.4 mm in females (n = 4), by lacking a tympanum, lacking males with vocal slits, and tips of digits narrow without circumferential grooves. In life, dorsal and lateral ground coloration is pale orange brown, reddish brown or grayish brown with or without grayish-brown mottling, and the venter is pale cream and pale gray mottled. A molecular phylogenetic analysis based on mitochondrial and nuclear DNA sequences inferred that the three new species belong to the Pristimantis danae species Group distributed in the montane forests and high Andean grasslands of central Peru, including P. albertus, P. aniptopalmatus, P. ornatus, and P. stictogaster. With the three new species, 133 species of Pristimantis are currently known from Peru, eight of which inhabit the puna.

Lung surface deformation prediction from spirometry measurement and chest wall surface motion.

The authors have developed and evaluated a method to predict lung surface motion based on spirometry measurements, and chest and abdomen motion at selected locations. A patient-specific 3D triangular surface mesh of the lung region was obtained at the end expiratory phase by the threshold-based segmentation method. Lung flow volume changes were recorded with a spirometer for each patient. A total of 192 selected points at a regular spacing of 2 × 2 cm matrix points were used to detect chest wall motion over a total area of 32 × 24 cm covering the chest and abdomen surfaces. QR factorization with column pivoting was employed to remove redundant observations of the chest and abdominal areas. To create a statistical model between the lung surface and the corresponding surrogate signals, the authors developed a predictive model based on canonical ridge regression. Two unique weighting vectors were selected for each vertex on the lung surface; they were optimized during the training process using all other 4D-CT phases except for the test inspiration phase. These parameters were employed to predict the vertex locations of a testing data set. The position of each lung surface mesh vertex was estimated from the motion at selected positions within the chest wall surface and from spirometry measurements in ten lung cancer patients. The average estimation of the 98th error percentile for the end inspiration phase was less than 1 mm (AP = 0.9 mm, RL = 0.6 mm, and SI = 0.8 mm). The vertices located at the lower region of the lung had a larger estimation error as compared with those within the upper region of the lung. The average landmark motion errors, derived from the biomechanical modeling using real surface deformation vector fields (SDVFs), and the predicted SDVFs were 3.0 and 3.1 mm, respectively. Our newly developed predictive model provides a noninvasive approach to derive lung boundary conditions. The proposed system can be used with personalized biomechanical respiration modeling to derive lung tumor motion during radiation therapy from noninvasive measurements.

Variations of the soft tissue thicknesses external to the ribs in Pectus Excavatum patients

BackgroundSurgical repair of pectus excavatum (PE) has become more popular due to improvements in the minimally invasive Nuss procedure. The pre-surgical assessment of PE patients requires Computerized Tomography (CT), as the malformation characteristics vary from patient to patient. ObjectiveThis work aims to characterize soft tissue thickness (STT) external to the ribs among PE patients. It also presents a comparative analysis between the anterior chest wall surface before and after surgical correction. MethodsThrough surrounding tissue segmentation in CT data, STT values were calculated at different lines along the thoracic wall, with a reference point in the intersection of coronal and median planes. The comparative analysis between the two 3D anterior chest surfaces sets a surgical correction influence area (SCIA) and a volume of interest (VOI) based on image processing algorithms, 3D surface algorithms, and registration methods. ResultsThere are always variations between left and right side STTs (2.54±2.05mm and 2.95±2.97mm for female and male patients, respectively). STTs are dependent on age, sex, and body mass index of each patient. On female patients, breast tissue induces additional errors in bar manual conception. The distances starting at the deformity's largest depression point at the SCIA are similar in all directions. Some diverging measures and outliers were found, being difficult to find similar characteristics between them, especially in asymmetric patients. ConclusionThe Nuss procedure metal bar must be modeled according to each patient's special characteristics. The studied relationships between STT and chest surface could represent a step forward to eliminate the CT scan from PE pre-surgical evaluation.

Juvenile dermatomyositis (JDM) sine myositis

Methods/case 6 y/o girl from Kazakhstan presenting with discrete heliotrope of upper eyelids, erythema of the chest and extensor surfaces of extremities, Gottron’s papules as well as scarred piecemeal necrosis on 1 finger and 2 toes. Close examination revealed nailfold tortuositas. Muscle strength was 5/5, CMAS 48/51. Inflammatory parameters were not elevated, transaminases, CK and aldolase in the normal range, ANA >1:2560. Follow-up over 12 months showed no progression or muscle involvement.

SU‐FF‐J‐21: An External‐Marker Based Non‐Respiratory Body Motion Monitoring System

The development of new technologies has leaded a trend of tighter target margin and longer treatment procedures in the new era of image‐guided radiotherapy. This prompts a concern of potential body motion of a patient during the treatment, especially for stereotactic body radiosurgery. The purpose of this study is to develop a technique to monitor the non‐respiratory motion of a patient, separated from the relatively large respiratory motion. BrainLab ExacTrac system is used as the platform for the study. Multiple infrared external markers are placed on a patient's chest and abdominal surfaces. The position of each marker is monitored with two infrared cameras. The motion signal of each marker, which is the mixture of respiratory and non‐respiratory motions, is recorded. The markers on the chest surface show much smaller, but correlated respiratory signals than those on the abdominal surface. The non‐respiratory component can be derived from the motion signal at the chest surface subtracting the respiratory component represented by the motion signal at the abdominal surface. A computer program has been written to calculate the two motion components in real‐time and was retrospectively tested in patients enrolled in a 4D‐gated‐CT protocol. Total of 24 patients were tested. The duration of recorded motion signals ranged from 10 to 25 minutes for different patients. The extracted non‐respiratory motion signal showed reduced respiratory ripples of less than 0.5 mm for most of the patients, with the maximal ripple of about 1.2 mm. It also showed slow‐drifts as well as some sharp spikes or irregular fluctuations. The slow‐drifts were <1.5mm for 8 patients, >1.5mm and <2.5mm for 6 patients, >2.5mm and <3.5mm for 5 patients, and >3.5mm for 3 patients with maximal drift of 6.5mm. This result suggests that monitoring non‐respiratory motion during treatment might be necessary.

Bow-thruster noise remediation in R O G E R R E V E L L E, AGOR-24

A program was initiated for Scripps Institution of Oceanography, sponsored by ONR, to silence the bow thruster in the research vessel ROGER REVELLE, AGOR-24. The ship suffered habitability problems during long-term dynamic positioning operations. A one-half-scale mockup of the ship’s bow thruster, sea chest, guard grids, and local hull surfaces was constructed for air tests. By measuring velocity distributions at the (absent) impeller location while separately drawing air through the mockup system at high velocity, it was demonstrated by calculation that the offending noise originated in unsteady cavitation of the impeller of the vertical-axis thruster. Several modifications to improve the flow were designed and evaluated in the mockup. Further, a modified impeller was designed on the basis of cavitation avoidance. The new impeller was designed-in-detail, manufactured, and installed along with several structural modifications of the thruster and sea chest, approved by the thruster manufacturer, during ship overhaul. No additional acoustic treatments were applied. Quantitative measurements of compartment levels of noise and vibration, and structural and water-borne noise were carried out to compare with premodification measurements. Results now indicate an absence of bow-thruster cavitation noise in adjacent compartments during DP operations. Thrust performance was preserved.

Characterization of dermatitis arising spontaneously in DS-Nh mice maintained under conventional conditions: another possible model for atopic dermatitis

DS-Nh (DS Nh/+) mice spontaneously develop dermatitis when they are housed in a conventional environment. In this study, we analyzed the clinical and histopathological features of dermatitis in DS-Nh mice, which is characterized by erythema, edema, and erosion on the face, neck, chest and flexor surfaces of their forelegs with marked scratching behavior. Histopathological examination, including immunohistochemistry, revealed that inflammatory cells consisting of mast cells, eosinophils, CD4-positive T cell-dominant lymphocytes and CD11b-positive macrophages infiltrated the skin lesions. The cytokine production pattern of inflammatory cells in a lesional skin tissue was shifted to the Th2-type (IL-4) rather than the Th1 type (IFN-γ). Serum IgE levels were elevated and correlated with the severity of the clinical skin conditions. These skin symptoms were observed in association with a colonization of Staphylococcus aureus. Similar clinical and histopathological symptoms were inducible with repeated percutaneous immunization of heat-killed S. aureus on the back of SPF DS-Nh mice. These results suggest that the spontaneous dermatitis that occurs in conventionally raised DS-Nh mice is comparable to a certain type of human atopic dermatitis (AD), which is associated with S. aureus, a recognized environmental factor . Thus, we consider that DS-Nh mice offer a useful model for investigating the pathogenesis of AD and for developing new therapeutic approaches or drugs for treating AD.

In Reply: Phototherapy Effect on the Incidence of Patent Ductus Arteriosus

I am sure that Dr Rojas' observation of the shield depicted in our article led to his calculation of 40% loss of the available skin surface. This patient represented one of the earliest entered into the study. After our first few patients, the size of the shield was considerably decreased. In general, the size of shields for 1, 000-g patients is approximately 4 x 5 cm. We have measured the area of the chest and abdominal surfaces and compared this to the area of the shield. The area covered by the shield covered 17% to 25% of the trunk surface in patients we measured.

Eosinophilic pustular folliculitis

We present the case of an American adult patient with eosinophilic pustular folliculitis. The majority of previously reported patients have been Japanese. Eosinophilic pustular folliculitis is a rare condition characterized by recurrent, peripherally expanding, sterile papulopustules and plaques. Hair-bearing areas such as the face, chest, back, and extensor surfaces of the upper arms are usually involved, although palms and soles can be affected as well. Histologic examination shows subcorneal and intrafollicular abscesses and spongiosis of the outer root sheath. The eosinophil is a prominent infiltrating cell, although mononuclear cells and neutrophils may also be seen. There is often a dense perivascular infiltrate of eosinophils in the dermis. Our patient was unusual in that he did not respond to multiple therapeutic regimens.

Electrocardiographic effects of myocardial ischemia induced by atrial pacing in dogs with coronary stenosis: I. Repolarization changes with progressive left circumflex coronary artery narrowing

The electrocardiographic effects of tachycardia in normal dogs and in dogs with progressive coronary stenosis were studied. In five animals, left atrial electrodes were surgically implanted and body surface isopotential patterns were recorded from 84 torso electrodes; pacing at rates of up to 250 beats/min increased recorded voltages registered during the ST segment but did not alter the spatial distribution of these potentials. In 10 dogs, an ameroid constrictor was also implanted about the left circumflex coronary artery. One week after surgery, pacing to rates of 250 beats/min had no effect on ST segment isopotential patterns. However, 2 and 3 weeks postoperatively, when significant coronary constriction was anticipated, pacing-induced ST segment depression was recorded along the inferior anterior and posterior chest surfaces. Abnormal negative voltages were more intense at 3 than at 2 weeks, but the distribution of these abnormalities was unchanged. This pattern was consistent with the location of ischemic myocardium. Calculation of early (10 to 40 ms) ST segment slopes demonstrated that downsloping forms were recorded over most of the area with abnormal ST segment voltages, but that horizontal or upsloping depression occurred at the margins of the abnormal zones. The findings suggest that this canine model may be a useful analog to clinical exercise stress testing to aid in evaluating the significance of clinical electrocardiographic patterns.