Popliteal Artery Occlusion after Total Knee Replacement Arthroplasty: A Case Report

The injury of popliteal artery in association with a total knee arthroplasty is rare with the incidence reported 0.03% to 0.05%, but the result of popliteal artery occlusion is extremely poor. Preexisting peripheral arterial disease, flexion deformity, tourniquet use, inadequate procedure during TKA, close proximity of popliteal artery to posterior cortex of tibia plateau, all of these are likely to increase the risk of the injury of popliteal artery during a knee replacement operation. We have experienced a patient who developed an arterial complication in association with a total knee arthroplasty and report the treatment as well as the discussion about the mechanisms of injury of popliteal artery.

Sonographic Findings of Coccygeal Abscess in the Neonates

PURPOSE: The purpose of this study was to report the sonographic findings of neonatal coccygeal abscess,previously not described. MATERIALS AND METHODS: Eighteen neonates (5-18 days old) presented with swelling in thecoccygeal area and by either open drainage (n=13) or follow-up after antibiotic therapy (n=5), this was diagnosedas coccygeal abscess. We retrospectively reviewed the size, shape, location, echo pattern and marginalcharacteristics of the abscesses, as seen on sonography, as well as their intradural content and relationship withthe spine. Additional MR images (n=5) were separately reviewed. RESULTS: Mean longest diameter of the abscesseswas 1.5cm (range, 0.8-2.3); they were oval or round and located in the subcutaneous fat layer. Echogenicitycompared with surrounding fat varied: in nine patients it was isoechoic, and in nine, hypoechoic. Internalechogenicity was homogenous in 14 patients and heterogeneous in four, and in seven cases, the margin of theabscess was well demarcated. Intradural structure and bony spines were normal, and the possibility of spinaldysraphism, could thus be excluded. All cases except one were correctly diagnosed by sonography and clinicalfindings; on sonography, the echogenicity of one lesion was exactly the same as that of lipoma, and it was thusmisdiagnosed. In cases where sonography revealed an isoechoic mass, the use of MR excluded the possibility oflipoma. Three of five cases showed marginal or diffuse enhancement on contrast enhanced MR images. CONCLUSION: Coccygeal absesses were confined to the subcutaneous fat layer and were either iso- or hypoechoic compared. withsurrounding fat. In neonates, abscess formation in the coccygeal area is possible, and coccygeal abscess shouldtherefore be included in the differentiation of coccygeal masses.

Acute Cholecystitis: Two-Phase Spiral CT Finding

PURPOSE: To describe the two-phase spiral CT findings of acute cholecystitis. MATERIALS AND METHODS: CTscans of nine patients with surgically-proven acute cholecystitis were retrospectively reviewed for wallthickening, enhancement pattern of the wall, attenuation of the liver adjacent to the gallbladder, gallstones,gallbladder distention, gas collection within the gallbladder, pericholecystic fluid and infiltration ofpericholecystic fat. RESULT: In all cases, wall thickening of the gallbladder was seen, though this was moredistinct on delayed images, Using high-low-high attenuation, one layer was seen in five cases, nd three layers infour. On arterial images, eight cases showed transient focal increased attenuation of the liver adjacent to thegall bladder;four of these showed curvilinear attenuation and four showed subsegmental attenuation. One caseshowed curvilinear decreased attenuation between increased attenuation of the liver and the gallbladder, andduring surgery, severe adhesion between the liver and gallbladder was confirmed. Additional CT findings wereinfiltration of pericholecystic fat (n=9), gallstones (n=7), gallbladder distension (n=6), pericholecystic fluid(n=3), and gas collection within the gallbladder (n=2). CONCLUSION: In patients with acute cholecystisis,two-phase spiral CT revealed wall thickening in one or three layers ; on delayed images this was more distint. Inmany cases, arterial images showed transient focal increased attenuation of the liver adjacent to the gallbladder.

The US Findings of Acute Nonperforated and Perforated Appendicitis in Children

PURPOSE: To analyse and interpret different sonographic findings in acute nonperforated and appendicitis. MATERIALS AND METHODS: In 46 cases of acute appendicitis in children(26 girls, 20 boys) proven by surgery, sonographic findings were reviewed retrospectively. The findings of nonperforated and perforated appendicitis were analysed, focusing on the size, shape and echogenicity of the appendix, echo patterns of periappendiceal abscesses, mesenteric lymphadenopathy, and the prevalence of appendicolith. RESULTS: A noncompressible distended appendix was present in 18 of 21 patients with nonperforated appendicitis and in 13 of 25 patients with perforation. In 18 patients with nonperforated appendicitis, the average diameter of distended appendix was 8.6mm;target appearance was noted in 16 patients and loss of echogenic submucosa in two. In 13 patients with perforated appendicitis, the average diameter of appendix was 9.1 mm;target appearance was noted in four patientsand loss of echogenic submucosa in nine. periappendiceal abscesses were present in 21 of 25 cases of perforated appendicitis, and the echogenicity of abscesses was mixed in 12 patients, hypoechogenic in eight, and hyperechogenic in one. Mesenteric lymphadenopathy was present in two of 21 patients with nonperforated appendicitis and in four of 25 with perforation. Appendicolith was detected on sonography in three of 25 patients with perforated appendicitis, but was found in seven patients during surgery. One patients with perforated appendicitis also had right side hydronephrosis. Sonographically false-negative results were obtained in sixcases. CONCLUSION: A sonographic examination was useful to differenciate perforated and nonperforated appendicitis in children. Loss of echogenic submucosa in the distended appendix and periappendiceal abscess formation were important findings in diagnosis of perforated appendicitis.