The prevalence and pattern of pneumatization of Onodi cell in Thai patients.

BACKGROUND: The Onodi cell (sphenoethmoidal cell) is an anatomical variation of the most posterior ethmoid air cell the pneumatizes laterally and/or superiorly to the sphenoid sinus and is intimately in contact with the optic nerve. If it is infected or goes unrecognized during surgery it may result in serious damage to the optic nerve. Nowadays, computed tomographic scans of paranasal sinuses (CT PNS) have been used to detect variations in paranasal sinus anatomy However there is a lack of data about the variations of Onodi cell. OBJECTIVE: To determine the prevalence and various patterns of Onodi cell. MATERIAL AND METHOD: Axial, coronal, sagittal and sagittal oblique (parallel to the optic canal) CT scans of the paranasal sinuses, nasopharynx, neck and orbit performed at Srinagarind Hospital between January 1, 2004 and November 30, 2006 were reviewed A pilot study was carried out to investigate the inter-rater reliability of the identification of Onodi cell between the radiologist and rhinologist until the kappa value was 0.74. During the main study, the radiologist and rhinologist interpreted the CT scans independently. If there was a discordant opinion concerning the presence of Onodi cell, a consensus was reached by discussion between the rhinologist and the radiologist. RESULTS: 187 CT scans (374 sides) were included Sagittal oblique view detected Onodi cell in 185 sides 49.5% (95% CI: 44.4-54.5). The patterns of Onodi cell were classified into three patterns. In the first pattern, the Onodi cell extended only superiorly to sphenoid sinus (46%; 95% CI: 38.9-53.1). In the second pattern, it extended only laterally to sphenoid sinus (1%; 95% CI: 0.3-3.9). The last pattern was a combined type, lateral and superior to sphenoid sinus (53%; 95% CI: 45.8-60.0). CONCLUSION: The prevalence of Onodi cell diagnosed by CT scans was 49.5% (95% CI 44.4-54.5) and the most common pattern was the combined type. This information may be useful for those who perform endoscopic sinus surgery.

Role of chest radiography in the diagnosis and follow-up of pulmonary metastasis in differentiated thyroid cancer.

BACKGROUND: Post-treatment I-131 whole body scan (WBS) is known to be a very sensitive test in detecting metastasis in differentiated thyroid cancer (DTC). Therefore, in the presence of this sensitive method, the role of chest radiography (CXR) in the diagnosis of pulmonary metastasis has been questioned. OBJECTIVE: The present study aimed to find the prevalence of pulmonary metastasis found on CXR in DTC patients who had negative post-treatment WBS. MATERIAL AND METHOD: Retrospective comparison was undertaken of CXR and post-treatment WBS routinely performed in 300 DTC patients during the time of I-131 treatment from January 2003 to December 2006 in the Department of Radiology. Radiographic patterns of pulmonary metastasis classified as single nodule, multiple nodules, lymphangitic metastasis and pleural metastasis were also recorded. RESULTS: Of the 300 DTC patients, 36 pulmonary metastases (12.0%) were diagnosed based on CXR and post-treatment I-131 WBS. Of these 36 cases, 11 (30.6%) were detected by both CXR and WBS, whereas 16 (44.4%) were detected by WBS alone and 9 (25.0%) by CXR alone. Seven of these 9 cases (77.8%) had lymphangitic pattern of pulmonary metastasis. CONCLUSION: Although routine CXR has a limited role in the diagnosis of pulmonary metastasis in DTC patients being treated with I-131, it is helpful in detecting pulmonary metastasis in patients with negative post-treatment WBS.

Selective transcatheter embolization for treatment of post-traumatic hepatic artery and portal vein pseudoaneurysms.

The authors report a case of post-traumatic hepatic artery and portal vein pseudoaneurysms caused by blunt abdominal trauma, with multiple organ injuries including liver laceration. Abdominal spiral CT, CDS and DSA were performed to confirm the diagnosis. Both pseudoaneurysms were treated successfully with selective transcatheter embolization.