Sonographic Findings after Total Hip Arthroplasty: Normal and Complications

PURPOSE: The purpose of this study was to determine the efficacy of sonography in the evaluation of normal pseudocapsular morphology and the detection of complications after total hip arthroplasty. MATERIALS AND METHODS: Between Janvary 1997 and June 2000, 47 patients [35 men and 12 women aged 24 to 84 (mean, 61) years] using real-time linear-array, convex US units with 3.5-MHz and 10-MHz transducers. Normal capsular morphology in 30 with total hip replacements, who had been asymptomatic for at least one year, was studied, and the prosthetic joint infection demonstrated in six of 17 who had experienced was confirmed at surgery or by US-guided aspiration. RESULTS: Sonograms indicated that a normal pseudocapsule lay straight over the neck of the prosthesis or was slightly convex toward the neck, and that the mean bone-to-pseudocapsule distance was 2.9 mm. However, in the 11 symptomatic patients in whom no evidence of infection was revealed by cultures, th mean distance was 4.7 mm; in the remaining six patients, whose joints were infected (a condition strongly suggested by the presence of extracapsular fluid), the mean distance was 5.5 mm, with no significant difference between the two groups. CONCLUSION: Sonography can be used to evaluate normal caspular morphology after total hip replacement and to diagnose infection around hip prostheses. In all patients in whom sonography revealed the presence of extra-articular fiuid, infection had occurred.

Measurement of Normal Size of Styloid Process with 3D Reconstruction CT

PURPOSE: To measure the normal size of the styloid process using 3D (three-dimensional) reconstruction CT. MATERIALS AND METHODS: We retrospectively analyzed 3D reconstruction images obtained after coronal and axial CT scanning of the temporal bone or neck of 115 patients. The length and shape of both sides of the styloid process, the location of its tip, and calcification of the stylohyoid ligament were retrospectively analysed. RESULTS: The mean length of the styloid process was 26.6 (+/-7.9)mm on the right side, and 26.4(+/-8.3)mm on the left, a statistically insignificant difference (p=0.694). Its mean length was 26.2 (+/-8.5)mm in men and 26.7 (+/-7.2)mm in women, a statically in significant difference (p=0.733). As for variation with age, mean length tended to increase until the third decade, but not beyond. Segmental type (104/230, 45.2%) and fragmental type (73/230, 31.7%) were more commonly seen in shape of styloid process, and tapering tip of styloid process (156/230, 67.9%) is more commonly seen than clubbing tip of it (74/230, 32.1%). The process was angulated in six cases (2.6%); its tip was more frequently located between the internal and external carotid artery (211 cases, 91.7%) than more medially (19 cases, 8.3%). In the former location, the length of the process was 26.2(+/- 7.2)mm, and in the latter, 37.0(+/-6.0)mm. The difference was statistically significant (p=0.000). Calcification had occurred in 33 cases (14.3%). CONCLUSION: The length of a normal styloid process was 18-32 mm. There were no statistically significant differences between its two sides, or between the sexes. Length tended to increase until the third decade, but not beyond. Predominantly the tip was located between the internal and external carotid artery, though the process was longer when its tip was located medially.

Central Lung Tumors with Obstructive Pneumonitis:Ultrasonographic Findings and Usefulness of Ultrasound-guided Biopsy

PURPOSE: To determine the ultrasonographic findings and assess the usefulness of ultrasound (US)-guided biopsy of central lung tumors in patients with obstructive pneumonitis. MATERIALS AND METHODS: Fourteen patients with central lung tumors causing obstructive pneumonitis, as seen on chest radiographs and chest CT scans, were examined between January 1997 and January 2000. In no patient conclusive histologic diagnosis obtained by means of bronchoscopic biopsy or sputum cytology. Eleven patients were men and three were women, and their ages ranged from 45 to 83 (mean, 64) years. For all examinations, real-time, linear-array, convex US units with a 3.75- and a 5.0-MHz transducer were used. The images obtained were analyzed for evidence of consolidation or atelectasis in the lung, demonstrable tumors, and tumor size and echogenicity. For US-guided percutaneous transthoracic biopsy, 19.5G automatic biopsy devices, were employed. RESULTS: Lung consolidation due to a wedge-shaped, homogeneous, hypoechoic lesion was revealed by sonographic fluid bronchograms, air bronchograms, air alveolograms, and visualization of intraparenchymal pulmonary vessels, which showed appropriate motion with respiration. The tumor presumed to be causing obstruction was seen as a hypoechoic nodule near the hilum or as a well-defined hyperechoic mass inside the partially consolidated lung. Pleural effusion was observed in one case. The cytologic findings indicated the presence of squamous cell carcinoma (n=4), adenocarcinoma (n=4), small cell carcinoma (n=3), non-small cell carcinoma (n=2) and large cell carcinoma (n=1). The success rate was 100%, and there were no complications. CONCLUSION: In patients with central lung tumors causing obstructive pneumonitis, chest ultrasonography and US-guided biopsy are useful adjunctive diagnostic modalities and techniques.

Radiologic Findings of Ovarian Fibrothe

PURPOSE: To evaluate the radiologic features of fibrothecoma of the ovary, which is a rare solid tumor originating from the ovarian sex cord-stroma. MATERIALS AND METHODS: The radiologic findings of 29 patients with pathologically-proven fibrothecoma of the ovary were retrospectively evaluated for bilaterality, size, shape, margin, echogenecity, CT attenuation, signal intensity on magnetic resonance imaging, calcification, and amount of ascites. RESULTS: All fibrothecomas were unilateral, and had well defined margins. The diameter of the mass was 4-18(mean, 9.6)cms. Elghteen of 29 tumors were round or oval with a smooth margin, and eleven were lobulated. The internal architecture of the tumor was purely solid in 21 patients, predominantly solid in six, and pre-dominantly cystic in two. A broad spectrum of sonographic features was apparent, including a homogeneously hypoechoic mass (with posterior shadowing in four cases, and without posterior shadowing in ten), a homoge-neously hyperechoic mass in seven cases, an anechoic mass with septatations in two, and a mixed echoic mass in six. On precontrast CT scans, the mass was isodense to the uterine myometrium in eight of nine cases, while on postcontrast scans the lesion was slightly hypodense to the myometrium in seven cases and isodense in one. On T1-weighted MR images, nine of ten cases showed a relatively homogeneous low signal intensity, while on T2-weighted images, signal intensity was homogeneously low in two patients and predominantly low with focal high intensity in seven of the other eight. On gadolinium-enhanced T1-weighted images, most tu-mors showed slight heterogeneous enhancement. Calcifications were present in two cases, and in two others there was a large amount of ascites. CONCLUSION: The characteristic finding of ovarian fibrothecomas is a well-defined, oval or lobulated homoge-neously solid mass, which on CT scans enhances less than uterine myometrium and demonstrates a predomi-nantly low signal intensity on both T1- and T2-weighted images. However, a predominantly solid mass with cystic components or a predominantly cystic mass may also be presented.

CT Findings of Change of the Maxillary Sinus after Caldwell-Luc Operation

PURPOSE: This study describes the CT findings of changes in the maxillary sinus after the Caldwell-Luc procedure. MATERIALS AND METHODS: The maxillary sinus-related findings in 35 cases among 20 patients(17 cases in 10 males and 18 cases in 10 females)who had undrgone the Caldwell-Luc procedure mean 14.6 years earlier were reviewed. CT scans were obtained in the axial and coronal planes, with 5mm thickness. By means of the t test, changes in the size of the bony wall of the maxillary sinus, as well as antral volume change, were compared with the normal maxillary sinus group(41 male and 23 female cases). Males and females were compared separately, and surgical bony defect of nasolabial antrotomy and nasoantral window, fibroosseous proliferation, compartmentation and mucosal thickening of the postoperative maxillary sinus were evaluated, as were findings of chronic or recurrent maxillary sinusitis and postoperative complications. RESULTS: Naso-labial antrotomy was clearly identified in 27 of 35 cases, and irregular bony surface in the remaining eight, as were 27 bony defects and one irregular bony margin among a total of 28 cases of nasoantral window. Due to shortening of the height of the orbit, reductions in maxillary width, nasoantral communication width and anteroposterior diameter of the maxilla, and widening of the width of the inferior meatus, the maxillary sinus tended to become hypoplastic and centripetally contracted. Reduced cavitary volume of the maxillary sinus was noted(p<0.05), and fibro-osseous proliferation(n=29), compartmentation(n=11), and mu-cosal thickening(n=22) of the postoperative maxillary sinus were also seen. There were findings of chronic si-nusitis(n=22), as well as complications of postoperative mucocele(n=3) and oroantral fistula(n=2) of the maxillary sinus. CONCLUSION: The characteristic maxillary sinus-related findings seen after the Caldwell-Luc procedure are helpful in distinguishing postoperative change from recurrent paranasal diseases and resulting complications.