COVID-19 vaccine-induced lymphadenopathies: incidence,course and imaging features from an ultrasound prospective study

Aimslymphadenopathy can occur after COVID-19 vaccination and when encountered at ultrasound examinations performed for other reasons might pose a diagnostic challenge. Purpose of the study was to evaluate the incidence, course and ultrasound imaging features of vaccine-induced lymphadenopathy.Methods89 healthy volunteers (median age 30, 76 females) were prospectively enrolled. Vaccine-related clinical side effects (e.g., fever, fatigue, palpable or painful lymphadenopathy) were recorded. Participants underwent bilateral axillary, supraclavicular and cervical lymph node stations ultrasound 1–4 weeks after the second dose and then again after 4–12 weeks in those who showed lymphadenopathy at the first ultrasound. B-mode, color-Doppler assessment, and shear-wave elastography (SWE) evaluation were performed. The correlation between lymphadenopathy and vaccine-related side effects was assessed using the Fisher’s exact test.ResultsPost-vaccine lymphadenopathy were found in 69/89 (78%) participants (37 single and 32 multiple lymphadenopathy). Among them, 60 presented vaccine-related side effects, but no statistically significant difference was observed between post-vaccine side effect and lymphadenopathy. Ultrasound features of vaccine-related lymphadenopathy consisted of absence of fatty hilum, round shape and diffuse or asymmetric cortical thickness (median cortical thickness of 5 mm). Vascular signal was mainly found to be increased, localized in both central and peripheral regions. SWE showed a soft cortical consistence in all cases (median value 11 Kpa). At follow-up, lymph-node morphology was completely restored in most cases (54/69, 78%) and in no case lymphadenopathy had worsened.ConclusionA high incidence of vaccine-induced lymphadenopathy was found in a population of healthy subjects, with nearly complete regression within 4–12 weeks.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40477-022-00674-3.     

Influence of visual feedback sampling on obstacle crossing behavior in people with Parkinson's disease

The purpose of the current study was to investigate the role of visual information on gait control in people with Parkinson's disease as they crossed over obstacles. Twelve healthy individuals, and 12 patients with mild to moderate Parkinson's disease, walked at their preferred speeds along a walkway and stepped over obstacles of varying heights (ankle height or half-knee height), under three visual sampling conditions: dynamic (normal lighting), static (static visual samples, similar to stroboscopic lighting), and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. In the static visual sampling condition only, the patients with Parkinson's disease made contact with the obstacle more often than did the control subjects. In the successful trials, the patients increased their crossing step width in the static visual sampling condition as compared to the dynamic and voluntary visual sampling conditions; the control group maintained the same step width for all visual sampling conditions. The patients showed lower horizontal mean velocity values during obstacle crossing than did the controls. The patients with Parkinson's disease were more dependent on optic flow information for successful task and postural stability than were the control subjects. Bradykinesia influenced obstacle crossing in the patients with Parkinson's disease.     

Assessment of hyperemia in acute appendicitis: Comparison between power Doppler and color Doppler sonography

The purpose of our study was to compare power Doppler sonography (US) and conventional color Doppler US in the diagnosis of acute appendicitis by revealing local signs of hyperemia. One hundred consecutive patients (46 males and 54 females, ages 7–61 years; mean, 24.7 years) with clinically suspected acute appendicitis were prospectively examined with power Doppler US and conventional color Doppler US. Of 38 patients who subsequently underwent surgery, appendicitis was proven in 34. The remaining 62 patients who were not submitted to surgery had no clinical evidence of appendicitis over a 2- to 6-month follow-up. At gray-scale US, the appendix was visualized in 30 (88.2%) of the 34 cases with pathologically proven acute appendicitis. Power Doppler US depicted a moderate to marked hypervascularity of the appendiceal wall and surrounding mesoappendix in 28 (93.3%) of these 30 patients. At conventional color Doppler US, flow signal within the appendiceal wall and surrounding mesoappendix was shown in only 21 (70%) of 30 cases (P<0.05). No false-positive diagnosis was made at either power or color Doppler US among the 62 patients without appendicitis. Power Doppler US is more sensitive than conventional color Doppler imaging for revealing signs of local hyperemia in acute appendicitis.