The Double Gut Point: A Novel Sonographic Sign of Pneumoperitoneum

Pneumoperitoneum is a life-threatening condition, caused by hollow organ perforation. The diagnosis is often difficult, and Point-of-care ultrasound can be useful to distinguish from different conditions, and early set the indication of urgent surgery. We report a critically ill patient presented to the Emergency Department with sudden increase in upper abdominal pain and distension with a diagnosis of small bowel obstruction on ultrasound using a curvilinear probe. After repeating the ultrasound using a linear probe, two dynamic points at mesogastrium very similar to the “double lung point” seen in thoracic ultrasound was detected. This “double gut point” due to bowel ischemia and perforation was confirmed on a computed tomography scan. In this case, the finding of an abdominal “double gut point” allowed us to diagnose pneumoperitoneum, being a novel sign not previously described, that could aid to diagnose small amounts of free air in the peritoneal cavity.

Accelerated Aging Characterizes the Early Stage of Alzheimer’s Disease

For Alzheimer’s disease (AD), aging is the main risk factor, but whether cognitive impairments due to aging resemble early AD deficits is not yet defined. When working with mouse models of AD, the situation is just as complicated, because only a few studies track the progression of the disease at different ages, and most ignore how the aging process affects control mice. In this work, we addressed this problem by comparing the aging process of PS2APP (AD) and wild-type (WT) mice at the level of spontaneous brain electrical activity under anesthesia. Using local field potential recordings, obtained with a linear probe that traverses the posterior parietal cortex and the entire hippocampus, we analyzed how multiple electrical parameters are modified by aging in AD and WT mice. With this approach, we highlighted AD specific features that appear in young AD mice prior to plaque deposition or that are delayed at 12 and 16 months of age. Furthermore, we identified aging characteristics present in WT mice but also occurring prematurely in young AD mice. In short, we found that reduction in the relative power of slow oscillations (SO) and Low/High power imbalance are linked to an AD phenotype at its onset. The loss of SO connectivity and cortico-hippocampal coupling between SO and higher frequencies as well as the increase in UP-state and burst durations are found in young AD and old WT mice. We show evidence that the aging process is accelerated by the mutant PS2 itself and discuss such changes in relation to amyloidosis and gliosis.

Characteristics and morphology of lipohypertrophic lesions in adults with type 1 diabetes with ultrasound screening: an exploratory observational study

IntroductionLipohypertrophy is a common complication of exposure to insulin therapy. Despite the prevalence of lipohypertrophy and its potentially hazardous effects on glucose regulation, it remains a relatively understudied problem in diabetes. The objective of this study was to characterize lipohypertrophic tissue using ultrasound in adults with type 1 diabetes.Research design and methodsAn observational study of 74 people with type 1 diabetes from a diabetes center in South East London. Participants’ insulin exposed areas were scanned with ultrasound, with a high-frequency linear probe (6–13 MHz). The observed tissue changes were described, measured and graded according to nodule size and thickness of the dermal layer.ResultsParticipants mean age and diabetes duration were 40.6 (±14.2) and 18.3 (±10.9) years, respectively, and 60% (n=44) were male. A total of 740 lipohypertrophic nodules were observed, ranging from 1.8 mm to 40 mm in width. The mean (SD/range) number of nodules per participants was 10.4 (±6.2/1–29). Delineation between the dermal layers was disrupted in all current injection sites. In 52 participants (70%), there was a 30% increase in dermal thickness compared with local none injected tissue, and in 36 participants (48%) the increase was 50%. The level of thickness was >3 mm in the abdominal areas of 22 (40%) of these participants and in thighs of eight participants (17.8%). Hypoechogenic areas suggestive of necrotic tissue were observed within the lipohypertrophic nodules of 22 (30%) participants. Needle length and nodule depth were correlated (r=0.69, p<0.001). A conceptual model of the insulin exposed tissue changes observed was constructed.ConclusionsThe study confirms that insulin-exposed tissue changes are heterogenous and has provided conceptual and grading frameworks for classifying these changes. Further studies are required to establish the clinical implications of these classifications, in relation to glucose regulation and other clinical parameters.

Ultrasound findings in subcutaneous plantar vein thrombosis: retrospective analysis of seven patients

Background Several disorders may result in forefoot pain. An uncommon cause of forefoot pain is subcutaneous plantar veins thrombosis (SCPVT) involving veins superficial to the plantar fascia. Purpose To describe the ultrasound (US) appearance of SCPVT, which has been described only once in the radiological literature. Material and Methods We performed a retrospective search of our PACS system from 2016 to 2020 to collect all cases of US-diagnosed SCPVT. We collected data on seven patients. Two radiologists analyzed the US images retrieved. All US examinations were performed with a multifrequency linear probe (frequencies in the range of 5–17 MHz). Results A localized plantar nodule was palpable in 86% of patients. The subcutaneous thrombosed vein appeared in all patients as a round or ovoid nodule located in the subcutaneous tissues that corresponded in four patients (4/5, 80%) to the painful palpable nodule. The size was in the range of 4–7 mm (mean = 5.4 mm). The thrombosed vein presented a connection with adjacent patent veins, appeared enlarged, and almost filled with hypo-isoechoic material, and in two patients (2/7, 29%), a thin peripheral fluid component surrounding the thrombus was detectable. Continuous scanning demonstrated slow blood movements inside the peripheral component due to blood circulation. Failure to compress the lumen of the thrombosed vein during the real-time US was evident in all patients. Conclusion SCPVT is a rare or underreported condition. Sonologists must know the US appearance of SCPVT to exclude other conditions and avoid unnecessary invasive studies.

The Relationship between Skinfold and Ultrasound Measures of Subcutaneous Fat in Untrained Healthy Males

Ultrasound measurement of adipose tissue offers an alternative measure of body composition with less technical skill requirement than skinfolds. However, the relationship between skinfold and ultrasound measurements of adipose tissue is uncertain. The aim of this study was to compare these measures in a healthy untrained male population. One hundred male participants (aged 18–40 years) of varying body compositions had skinfold measures taken at the biceps, triceps and front thigh sites. Ultrasound measures were also taken at the same sites using B-wave ultrasound with a linear probe in the transverse plane. Strong, significant (p < 0.01), positive correlations were observed between skinfold and ultrasound measures at the biceps (r = 0.828), triceps (r = 0.813), and front thigh (r = 0.888) sites. However, there was significant (p < 0.01) variance between the techniques at all measurement sites. Whilst skinfold and ultrasound measures of adipose tissue have good linear agreement, skinfolds are consistently higher at all sites indicating a difference in the nature of the tissue measured via each technique. The exact nature of the relationship should be established on a population-specific basis.

Ultrasonography Method of Deep Cervical Muscles and Thickness Measurement Reliability in Cervicogenic Headache and Healthy Subjects:APilot Study

Introduction: In Cervicogenic Headache (CGH), motor control of muscles is impaired and deep upper neck muscles (extensor and flexor muscles) become atrophied. In this research, thickness measurement of Longus Capitis (LCap), Rectus Capitis Posterior Major (RCPM), and Obliquus Capitis Superior (OCS) muscles were conducted and intra-rater reliability of the thickness measurement of these muscles was assessed in CGH and healthy subjects. Materials and Methods: Twenty subjects, including 10 healthy subjects (19-32 years old) and 10 CGH patients (20-35 years old) participated in this study. LCap thickness was measured at the level of C3-C4 in the supine position and posterior muscles (RCPM and OCS) thickness at the C1-C2 level in the sitting position. All ultrasound images were captured by a linear probe with a 50-mm footprint in B mode option and frequency range of 9-12 Hz. Intraclass Correlation Coefficients (ICC), Standard Error Of Measurement (SEM), and the Smallest Detectable Difference (SDD) were calculated for data analysis. Results: The ICC for thickness measurement of LCap was from 0.70 to 0.91 (good to excellent), for RCPM thickness was from 0.69 to 0.94 and for OCS muscle thickness was from 0.87 to 0.98. SEM values for LCap were between 0.08 and 0.25 and the SDD values between 0.22 and 0.71. SEM values for RCPM were between 0.22 and 0.43 and these values were reported for OCS muscle between 0.19 and 0.45. Conclusion: The results indicated that the presented position and the level of ultrasonography in this study are appropriate and ultrasound is a reliable tool to measure the deep upper neck muscle thickness in CGH and healthy subjects.

Relationship of the optic nerve sheath diameter and repeated invasive intracranial pressure measures in traumatic brain injury patients; a diagnostic accuracy study

Objective: The purpose of this study was to quantitatively evaluate if the use of the optic nerve sheath diameter (ONSD) can be a suitable noninvasive surrogate approach for repeated invasive intracranial pressure (ICP) measures. Methods: The study used a sample of 22 adult patients with traumatic brain injury (TBI) from an in intensive care unit (ICU). ICP levels were measured using the gold standard and recorded in cmH20. ONSD was measured using ultrasonography with 5.6-5.7 MHz linear probe and recorded in millimeters. The data analysis was done using STATA software version 15. Results: The results showed a strong positive correlation between ICP and ONSD (r = 0.743, p = 0.001). The accuracy of the sonographic ONSD declined over time, starting from a high of 90.9% at the baseline and declining to a low of merely 20.0% after 48 hours. Conclusion: These findings indicate that the ONSD approach could be very useful alternative and noninvasive method for monitoring ICP.

ON THE INFLUENCE OF THE SIZE OF FLAKE GRAPHITE INCLUSIONS AND ITS VOLUME CONTENT ON THE ACOUSTIC PARAMETERS OF CAST IRON AND THE CHARACTERISTICS OF ULTRASONIC LONGITUDINAL WAVE SIGNALS

Algorithms have been presented for calculating the velocity (in the approximation of a fine-layered model) and the attenuation coefficient of a longitudinal ultrasonic wave in cast iron, depending on the average size of graphite elements and its volume content, the calculation results for which are qualitatively confirmed experimentally. The calculation was performed using a fine-layered model of the structure, the graphite inclusions were described in the form of plane-parallel layers placed in an isotropic elastic medium (metal base). Computer simulation of acoustic paths for a mediumcast iron with flake graphite for standard direct converters is carried out in order to study the influence of such a medium on the characteristics of transmitted and received signals during ultrasonic testing. In the course of the research, a previously developed model was used to calculate the attenuation coefficient of longitudinal waves in cast iron with flake graphite due to their Rayleigh and phase scattering on graphite inclusions. Computer simulation of the acoustic characteristics of the signals of a direct linear probe with a phased array in cast iron with flake graphite was carried out, during which the shape of the acoustic pulses of the longitudinal wave was calculated, depending on the distance traveled by the wave and the value of the attenuation coefficient for various models of cast iron. The main modeled characteristics of the transducer include the directivity characteristic and the change in the signal amplitude along the acoustic axis. It is shown that for cast iron with flake graphite, there are cases when the directivity of the probe with a phased array transmitted into the cast iron is practically absent.