Rationale and Objectives: To measure the impact of 1-year interventional fellowship training on fluoroscopic time and contrast media utilization in uterine artery embolization (UAE).Materials and Methods: Retrospective single institution analysis of 323 consecutive UAEs performed by 12 interventional fellows using a standardized protocol. Fluoroscopy time and contrast media volume were recorded for each patient and correlated with stage of fellowship training. Preprocedure uterine volume (using MRI or ultrasound) was used as a measure of procedural complexity. Regression analysis was conducted per trainee factoring in duration of training, procedure number, supervising radiologist, uterine volume, and outcome variables of fluoroscopy time and contrast media volume.Results: Median number of patients treated per trainee was 27 (range, 16-43) with mean fluoroscopic time 24.5 minutes (range, 4-90 min) and mean contrast volume 190 mL (range, 50-320 mL). Increasing uterine volume had no significant effect (P>.05) on fluoroscopic time but significantly increased (P<.001) contrast media volume. Significant training effect was identified with decrease in fluoroscopic time (P<.001) and decrease in contrast volume (P =.02) over training. Over the course of a 1-year fellowship, these summed to a decrease of 12 minutes in UAE fluoroscopy time and 17 mL less contrast.Conclusion: A significant (P<.05) training effect that is clinically relevant was demonstrated over the course of a yearlong interventional radiology fellowship program in performance of a standardized protocol for UAE. This data supports fellowship training as a basis for UAE credentialing and privileging.

The basic histopathological pattern of organizing pneumonia (OP) is well recognized, but the contexts in which it is encountered continue to increase. In parallel with an appreciation of new causes and associations of OP, an understanding of OP in the spectrum of lung injury and repair has evolved. There is an increasing array of HRCT manifestations of OP, some of which have only recently been described. This article concentrates on new concepts surrounding OP and highlights newly described imaging patterns.

The atoll sign A man presented as an urgent referral to the interstitial lung disease outpatient clinic with a 5 week history of fever, night sweats, shortness of breath and malaise.His admission chest x-ray showed patchy consolidation within both lungs, and a subsequent CT demonstrated multiple parenchymal ring opacities (figure 1 and figure 2A).On the basis of the unusual CT appearances he subsequently proceeded to an open lung biopsy which demonstrated polypoid buds of intra-alveolar granulation tissue or Masson bodies, consistent with a histopathological diagnosis of organising pneumonia (figure 3).He was treated with intravenous methylprednisolone and hydroxychloroquine to which he initially responded.Over the next 5 years he had several relapses clinically and radiologically which required pulse doses of methylprednisolone.Once stable, his medication was tapered and eventually stopped.Repeat CT imaging at this time revealed no residual parenchymal abnormalities.No definite cause for his illness was found and, following a multidisciplinary evaluation of his case, a final diagnosis of cryptogenic organising pneumonia was made.Crescentic or ring-shaped opacities surrounding an area of ground-glass opacification occasionally seen in the setting of organising pneumonia were first described by Voloudaki 1 and later coined the 'Atoll sign' by Zompatori. 2Kim et al. documented it in 19% of cases of cryptogenic organising pneumonia. 3 The word Atoll is derived from the Maldivian word 'atholhu' meaning an island consisting of a circular coral reef surrounding a lagoon (figure 2B).Although originally thought to be specific for organising pneumonia, this CT appearance has been described in a variety of other diseases including sarcoidosis, 4 Wegener granulomatosis, 5 lymphomatoid granulomatosis, 6 pulmonary paracoccidiomycosis 7 and non-specific interstitial pneumonia, 8 and under different names including the 'reversedhalo' sign and the 'fairy-ring' sign.Histopathologically the ground-glass opacification centrally represents septal inflammation, and cellular debris within the airspaces and the peripheral crescentic or ring-shaped opacity represents organising pneumonia in the alveolar ducts. 1 From a learning perspective, although this striking CT appearance is well documented in organising pneumonia, it should alert the radiologist and physician to other possible diagnoses, of which Wegener granulomatosis is particularly important.