Lymph Node Metastases in Thyroid Carcinomas: CT Diagnosis

PURPOSE: To determine the usefulness of CT for diagnosing metastases to primary and secondary echelon lymph nodes (LNs) and to investigate various CT findings of metastatic LNs in thyroid carcinomas. MATERIALS AND METHODS: We retrospectively reviewed the CT and histologic findings in 59 patients with thyroid carcinomas who had undergone thyroidectomy and neck dissection. Primary echelon LNs (Level VI) were removed by central neck dissection in all patients, and in 21, a total of 136 levels of secondary echelon LNs (Level II-V) were excised away by lateral neck dissection. CT criteria of metastatic LNs included large size, significant homogeneous enhancement, calcification, and cystic change. We evaluated the ability of CT to detect primary and secondary echelon LN metastasis and tried to determine which CT features were useful for the diagnosis of LN metastasis. RESULTS: Histologically, LN metastasis was found in 31 (53%) of 59 patients, including 30 with metastasis to primary echelon LNs. Of the 136 levels of secondary echelon LNs resected in 21 patients, 44 were found at histology to harbor metastatic foci. The sensitivities, specificities, positive and negative predictive values, and accuracies of CT in the diagnosis of metastasis to primary and secondary echelon LNs, respectively, were 27% and 93%, 100% and 93%, 100% and 87%, 57% and 97%, and 63% and 93%. While all secondary echelon LNs with at least one of the following CT criteria-large size (n=19), cystic or necrotic change (n=14), or calcifications (n=8)-were histologically proven to be metastatic, six (24%) of 25 such LNs with a sole sign of significant enhancement at CT were found to be due to reactive lymphadenopathy. CONCLUSION: Although CT was unable to detect metastasis to primary echelon LNs, it was useful in the detection of secondary echelon LN involvement. Large size, cystic change, and calcification are considered highly reliable signs of metastatic LNs.

Imaging Findings of Acute Abdomen with Intraperitoneal Tuberculosis

Acute abdomen caused by abdominal tuberculosis is a rare manifestation, and includes bleeding of a gastric or ileal ulcer, obstruction of the small bowel by an adhesive band, perforation of the ileum, ileocolic intussusception and fistula, and mesenteric abscesses caused by necrotic lymph nodes. The clinical and radiologic features of these complicated tuberculosis may mimic other acute abdominal diseases. Although not definitive, careful evaluation of the radiologic findings of the bowel wall, mesenteric fat infiltration, and lymph node enlargement may provide useful diagnostic clues to the presence of acute abdomen due to tuberculosis.

Shape and Incidence of Rib Variations in Chest Radiographs / 결핵

BACKGROUND: The literature on variations of rib is limited. Very little has been written in the radiological journal of this country on the subject. It seemed of interest to investigate the nature and incidence of congenital variations in a series of routine chest roentgenograms. The topic of rib variations has not been covered extensively in the radiological journals in Korea. This has presented an opportunity to investigate the nature, type, shape and incidences of congenital rib variations in normal Korean adults from a series of routine roentgenograms. METHODS: Chest radiographs of 5,000 adults (,) who visited our hospital for a routine check-up or for employment physical examinations from January 1996 to September 1998, were consecutively reviewed. The sex distribution consisted of 2,827 male males and 2,173 females (ratio of 1.3:1) with the age range between 19 and 65 years (mean age: 34.6 years). The chest PAs was were analyzed for the presence, type, location, and shape of the rib variations (.) From this data, and we the incidence of each type of variations was calculated. RESULTS: Seventy-six of the 5000 adults (1.52%), 63 male (2.23%) and 13 female (0.6%), showed 88 cases of rib variation (Table 1). Bifid rib (n=35) was the The most common variation was the bifid rib (n=35), followed by hypoplasia of the rib (n=22), flaring of the rib (n=18), bridging of the ribs (n=7), cervical ribs (n=3), and fusion of between ribs (n=3) (Table 2). (New paragraph)Bifid The bifid rib (Table 1) was found most frequent in the right fourth rib (12/35, 34.3%), followed by the left fifth rib (6/35, 17.1%) and right third rib (6/35, 17.1%). Hypoplasia of the rib was common in first rib (20/22, 90.9%). Flaring of the rib was common at fourth rib (8/18. 44.4%, right and left combined) (,) and bridging between ribs was common between first and second rib (3/7, 42.9%). CONCLUSION: The percentage of incidence of rib variations in adults was 1.52%. Bifid rib was the most common variation, followed by hypoplasia, flaring, bridging, cervical rib, and fusion of ribs(,) in decreasing order.