Object The authors conducted a study to compare the sensitivity and specificity of helical CT angiography (CTA) and digital subtraction angiography (DSA) in detecting intracranial arterial injuries after penetrating traumatic brain injury (PTBI). Methods In a retrospective evaluation of 48 sets of angiograms from 45 consecutive patients with PTBI, 3 readers unaware of the DSA findings reviewed the CTA images to determine the presence or absence of arterial injuries. A fourth reader reviewed all the disagreements and decided among the 3 interpretations. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CTA were calculated on a per-injury basis and in a subpopulation of patients with traumatic intracranial aneurysms (TICAs). Results Sensitivity of CTA for detecting arterial injuries was 72.7% (95% CI 49.8%–89.3%); specificity, 93.5% (95% CI 78.6%–99.2%); PPV, 88.9% (95% CI 65.3%–98.6%); and NPV, 82.9% (95% CI 66.4%–93.4%). All 7 TICAs were correctly identified by CTA. Sensitivity, specificity, PPV, and NPV of CTA in detecting TICAs were 100%. To compare agreement with DSA, the standard of reference, confidence scores categorized as low, intermediate, and high probability yielded an overall effectiveness of 77.8% (95% CI 71.8%–82.9%). Conclusions Computed tomography angiography had limited overall sensitivity in detecting arterial injuries in patients with PTBI. However, it was accurate in identifying TICAs, a subgroup of injuries usually managed by either surgical or endovascular approaches, and non-TICA injuries involving the first-order branches of intracranial arteries.

Bacterial and viral infection of the intraparotideal and periparotideal lymph nodes, or of the glandular parenchyma, can lead to inflammatory and subsequently suppurative changes, which can result in abscess formation. Sonography allows a detailed morphological evaluation of the gland and has an important value, complementary to clinical examination, in the study of parotid inflammatory diseases. Specifically, sonography defines lesion's characteristics and, in a large number of cases, also its nature and, among the various imaging techniques, it is considered first-line imaging for the evaluation of parotid abscesses, which are characterized by hypo-anechoic lesions, with irregular margins. Color Doppler signals are peripheral to the abscess. If combined with color Doppler, sonography is important not only in diagnosis, but also in the evaluation of therapeutic efficacy and as a guide to the aspiration and drainage of abscesses. The rarity of some of these lesions led us to publish this mini-pictorial essay.Keywords Salivary glands Á Sonography Á Abscess Riassunto Le infezioni batteriche e virali dei linfonodi intraparotidei e periparotiedei, o del parenchima ghiandolare, provocano una risposta infiammatoria e successivamente possono portare a suppurazione e a formazione di ascessi. L'ecografia consente di effetuare una valutazione morfologica dettagliata della ghiandola ed ha un valore importante, complementare all'esame clinico, nello studio delle malattie infiammatorie parotidee, poichè permette di definire le caratteristiche della lesione e, in un gran numero di casi, anche la loro natura; di conseguenza, tra le diverse metodiche di imaging, l'ecografia viene considerata quella di primo livello per lo studio degli ascessi parotidei, che si presentano come lesioni ipo-anecogene, con margini irregolari. La valutazione mediante color-Doppler mostra la presenza di segnali periferici alla lesione ascessuale. Oltre all'importanza per la diagnosi, l'ecografia, in combinazione con il color-Doppler, è utile nel follow-up e per guidare gli esami bioptici ed il drenaggio delle lesioni. Poichè alcune di queste lesioni sono rare, abbiamo deciso di pubblicare questo mini-pictorial essay.

The risk model developed may help radiologists suggest the possibility of TON and prioritize ophthalmology consults. However, future external validation of this prediction model is necessary.