Irion et al., "Reversed halo sign in active pulmonary tuberculosis: criteria for differentiation from cryptogenic organizing pneumonia," American Journal of Roentgenology, vol.
Izumi et al., "Pathophysiological implication of reversed CT halo sign in invasive pulmonary mucormycosis: a rare case report," Diagnostic Pathology, vol.
Kontoyiannis, "The diagnostic value of halo and reversed halo signs for invasive mold infections in compromised hosts," Clinical Infectious Diseases, vol.
A pulmonary nodule with the halo sign observed with high-resolution CT is an important and early sign of IPA; however, the halo sign is a non-specific imaging finding that may be observed in other diseases (7), (8).
reported that direct detection of vessel occlusion, which was defined as an interruption of a vessel at the border of a focal nodular pulmonary lesion, is an earlier finding than the halo sign and may be useful in the early diagnoses of IPA (10).
Bowel wall fat halo sign
in patients without intestinal disease.
"The density of the intramural stratum of the halo sign varied from -75 to +33 Hounsfield units," Dr.
All patients with halo signs had uniform, continuous stratification of the bowel wall.
It was concluded that "CT halo sign" is more specific for aspergillosis than cavitation and air crescent sign (13).
The various lesions identified were macronodules with halo sign, cystic bronchiectasis with mucus impaction in dilated bronchi giving "finger in glove" appearance, fungal ball in preformed cavities of lung giving "air crescent" or meniscus sign (14).
Finding Pediatric (N=9) Adult (N=7) Nodule without halo sign
3 (33.3%) 4 (57.1%) Nodule with halo sign
2 (22.2%) 2 (28.6%) Pneumothorax 1 (11.1%) 0.0 Unspecific infiltrate 3 (33.3%) 1 (14.3%) Table 4.