Predicting Neck Abscess with Contrast-Enhanced Computed Tomography

Abstract

Neck abscesses are difficult to diagnose and treat. Currently, contrast-enhanced computed tomography (CECT) is the imaging modality of choice. The study aims to determine the predictive value of CECT findings in diagnosing neck abscess, causes of neck abscess and the most common neck space involved in the local population. 84 consecutive patients clinically suspected to have neck abscess who underwent CECT and surgical confirmation of pus were included. Demographic and clinical data were recorded. 75 patients were diagnosed as having neck abscess on CECT; out of those 71 patients were found to have pus. Overall CECT findings were found to have a high sensitivity (98.6%) and positive predictive value (PPV) (94.7%) but lower specificity (67.2%) in diagnosing neck abscess. The CECT diagnostic criterion with the highest PPV is the presence of rim irregularity (96%). The most common deep neck space involved is the submandibular compartment, which correlates with the finding that odontogenic cause was the most common identifiable cause of abscess in the study population. Thus, in a patient clinically suspected of having neck abscess, CECT findings of a hypodense mass with rim irregularity are helpful in confirming the diagnosis and guiding clinical management.

Diagnostic accuracy of contrast-enhanced CT for neck abscesses: A systematic review and meta-analysis of positive predictive value

“…Regarding the effects of morphological properties of the abscess on PPV, 9 studies (39%) reported on rim enhancement ( Table 2 ) [ 8 , 14 , 16 , 18 , 19 , 21 , 24 , 26 , 30 ], and 10 studies (43%) reported on abscess diameter [ 8 , 10 , 12 , 14 , 16 , 19 , 21 , 22 , 24 , 26 ]. The meta-regression analysis found no overall effect of the moderators (CT criteria for an abscess, size of collection, rim enhancement, pediatric patients, or publication age) (p = 0.306).…”

“…Six studies reported sensitivity and specificity [ 12 , 14 , 15 , 26 , 28 , 29 ], and two additional studies reported sensitivity alone [ 20 , 23 ]. Sensitivity ranged from 0.68 to 0.99, and specificity from 0.18 to 0.63 ( Table 1 ).…”

“…Another study reported that HU<32 was seen in 85% of abscesses and 40% of phlegmons [ 19 ], indicating a large overlap between the two conditions. One study found even higher HU in drainable than in non-drainable collections [ 14 ]. Thus, HU values gathered from included studies indicate too much overlap between values of abscesses and phlegmons to make definite recommendations for reliable cut-offs for clinical practice.…”

“…Complete rim enhancement in late stages of abscess formation may explain some of the false negatives [ 28 , 29 ]. Indeed, complete rim enhancement has been reported to be present in 42–82% (average 61%) of patients with surgically confirmed abscesses [ 14 , 16 , 21 , 26 , 30 ] ( Table 2 ). Overall, on average 88% of patients with surgically confirmed abscesses have been reported to present either partial or complete rim enhancement on CT ( Table 2 ).…”

Subphrenic abscess secondary to cervical abscess and fasciitis from dental focus: case report

“…Perivascular and prevertebral spaces are contiguous with the upper mediastinum and pretracheal space with the anterior mediastinum. Infections affecting such spaces show a higher chance of evolving to mediastinitis [17, 18].…”