A useful tool - systematic checklist for evaluating sinus scans

Inter Observer Agreement Among Radiologist and Otorhinolaryngologists on Paranasal Sinus Computed Tomography Scans in Chronic Rhinosinusitis

To evaluate inter observer agreement between Radiologist and Otorhinolaryngologists in identifying important structures and pathologies on pre operative computed tomography (CT) scans of paranasal sinus (PNS) in chronic rhinosinusitis (CRS). A retrospective review of CT scans PNS of CRS patients. Archived CT scans were evaluated by 3 observers, similarly experienced radiologist and otorhinolaryngologist and a less experienced otorhinolarygologist. The degree of intra- as well as inter observer agreement was assessed by Cohen's kappa statistics. A moderate and a fair inter observer agreement was noted among experienced radiologist and otorhinolaryngologist; & experienced experts and less experienced otorhinolaryngologist respectively. The greatest disagreements among all observers were found in superior attachment of uncinate process, optic nerve's relationship with sphenoid sinus and dehiscence of anterior ethmoid canal. The present study demonstrated a considerable inter observer variability among radiologists and otorhinolaryngologists, irrespective of their experience in the field of speciality. A few critically important structures which showed an unsatisfactory level of agreement and thus need to be sought after with more training and practice, were also identified. These included Keros type, optic nerve's location, dehiscence of anterior ethmoid artery, vidian and maxillary nerves, lamina papyracia defect, sphenoid sinus pneumatization and attachment of uncinate process. The study also emphasized the importance of inter disciplinary conferences for pre operative evaluation of sinus CT scans of CRS patients.

[Objective and subjective assessment of a structured approach to computed tomography scans of the paranasal sinuses]

BACKGROUND

Sound knowledge of individual anatomy is essential in sinus surgery to prevent potentially serious complications. For the paranasal sinuses, computed tomography (CT) is the imaging technique of choice to preoperatively analyze individual anatomy and the extent of disease.

OBJECTIVE

The purpose of this study was to evaluate the usefulness of a CT checklist to identify relevant anatomic variants in CTs of the paranasal sinuses.

MATERIALS AND METHODS

Junior and senior otolaryngology residents were asked to assess sinus CT scans for anatomic variants before and after implementation of the CLOSE mnemonic (cribriform plate, lamina papyracea, Onodi cell, sphenoid sinus pneumatization, and [anterior] ethmoidal artery). The rate of correctly identified variants was calculated. A questionnaire was distributed for subjective evaluation of the usefulness of the checklist.

RESULTS

Six junior and six senior residents were included in the study. The rate of correctly identified anatomic variations significantly improved from 23.1 to 50.9% and 24 to 39.8%, respectively, after implementation of the CLOSE mnemonic. The subjective evaluation of the CLOSE criteria showed very positive results.

CONCLUSION

The structured approach to sinus CT scans using CT criteria can improve identification of critical anatomic variants in CT scans of the paranasal sinuses and is rated highly positively by residents in training.

Fool me twice: delayed diagnoses in radiology with emphasis on perpetuated errors

OBJECTIVE

We hypothesized that delayed diagnoses in radiology are not recognized on subsequent radiologic examinations because of multiple types of errors.

MATERIALS AND METHODS

Six hundred fifty-six radiologic examinations with delayed diagnoses were collected from July 1, 2002, to January 31, 2010. Each case was reviewed by two radiologists together, and the diagnostic errors were classified according to our modified scheme with consensus between the radiologists.

RESULTS

There were a total of 1269 errors. The range of days elapsed from the initial error in interpretation to the correct diagnosis was 0-4611 days, with an average of 251 days. The percentage for each type of error was 0.9% (n=11) for type 1, 9% (n=110) for type 2, 3% (n=39) for type 3, 42% (n=535) for type 4, approximately 0% (n=1) for type 5, 2% (n=29) for type 6, 5% (n=59) for type 7, 2% (n=20) for type 8, 7% (n=92) for type 9, 22% (n=288) for type 10, 0.5% (n=6) for type 11, and 6% (n=79) for type 12. The correct diagnoses were not recognized on subsequent radiologic examinations in 196 of 656 cases (30%).

CONCLUSION

Delayed diagnoses were not recognized on subsequent radiologic examinations in about one third of the cases. The most common types of error were underreading, satisfaction of search, faulty reasoning, and location of the finding.