Risk factors of converting to laparotomy in laparoscopic appendectomy for acute appendicitis.

PURPOSE: Laparoscopic appendectomy (LA) for acute appendicitis has several advantages over open appendectomy (OA). In cases of complicated appendicitis, LA is converted to OA at a constant rate, though converting appendectomy (CA) has several disadvantages. We retrospectively determined preoperative risk factors for failure of LA and subsequent conversion to OA. METHODS: Consecutive cases of preoperative computed tomography (CT) and attempted LA were retrieved from our hospital database and grouped by procedure (LA versus CA). Patients with negative appendectomies (n = 28), opened appendectomy (n = 210), delayed interval appendectomy (n = 3), or who were <14 years of age were excluded. RESULTS: Average patient age, preoperative C-reactive protein (CRP) level, and diffuse peritonitis were significantly different between the groups. CT inflammation and occurrence of complicated appendicitis were significantly higher in CA than LA. Conversion to OA was mostly because of dense adhesions, diffuse peritonitis, and difficulties in excision of the appendix due to perforation or severe inflammation from surgical point of view. Postoperative complications were significantly lower in LA than CA, although the rate of intraoperative abscess was not different. CONCLUSION: Most patients with acute appendicitis can be successfully treated with LA. We identified the following significant risk factors of CA: CT inflammation grade 4 or 5; complicated appendicitis; higher preoperative CRP level; and diffuse peritonitis.

Predictors of microscopic portal vein invasion by hepatocellular carcinoma: measurement of portal perfusion defect area ratio.

OBJECTIVE: Microscopic portal vein invasion (PVI) by cancer cells is a poor prognostic factor after hepatic resection for hepatocellular carcinoma (HCC). The aim of this study is to predict PVI preoperatively in patients with HCC. METHODS: We studied 46 hepatectomized patients who had HCC without any portal venous invasion detected during preoperative radiographic evaluation. We defined the portal perfusion defect area ratio (PPDAR) as the following: the quotient of the maximal portal perfusion defect area, on computed tomography during arterio-portography (CTAP) is divided by the maximal tumor area on magnetic resonance imaging (MRI) or CT. RESULTS: The median PPDAR was 1.3 (mean 1.4 +/- 1.1; ranged from 0.7 to 5.8). The incidence of PVI was 4.5% in patients with a PPDAR <1.3, 35.7% in those with a PPDAR of 1.3-1.6, 70% in those with a PPDAR > or = 1.6 (P = 0.0005). When analyzing the preoperative value of different cut-off points for the PPDAR, the lowest P-value by Fisher's exact test was achieved when the PPDAR threshold was 1.6 (P = 0.0012). The sensitivity was 58%, and specificity was 91% with this cut-off value. On univariate analyses, factors that significantly correlated with PVI were PPDAR (P = 0.0012), serum levels of des-gamma-carboxy prothrombin (P = 0.033), and tumor size (P = 0.0126). On multivariate analysis, PPDAR was the only significant independent predictor of PVI. CONCLUSION: Our study shows that PPDAR is a new concept, which is useful in predicting PVI and that a value > or = 1.6 is predictive of PVI.

Prognosis of hepatocellular carcinoma accompanied by microscopic portal vein invasion.

AIM: To investigate the prognostic factors in patients with hepatocellular carcinoma (HCC) accompanied by microscopic portal vein invasion (PVI). METHODS: Of the 267 patients with HCC undergoing hepatic resection at Aso Iizuka Hospital, 71 had PVI. After excluding 16 patients with HCC that invaded the main trunk and the first and second branches of the portal vein, 55 patients with microscopic PVI were enrolled. RESULTS: The patients with HCC accompanied by microscopic invasion were divided into two groups: solitary PVI (PVI-S: n = 44), and multiple PVIs (PVI-M: n = 11). The number of portal vein branches invaded by tumor thrombi was 5.4 +/- 3.8 (2-16) in patients with PVI-M. In cumulative survival, PVI-M was found to be a significantly poor prognostic factor (P = 0.0019); while PVI-M and non-anatomical resection were significantly poor prognostic factors in disease-free survival (P = 0.0213, and 0.0115, respectively). In patients with PVI-M, multiple intrahepatic recurrence was more common than in the patients with PVI-S (P = 0.0049). In patients with PVI-S, non-anatomical resection was a significantly poor prognostic factor in disease-free survival (P = 0.0370). Operative procedure was not a significant prognostic factor in patients with PVI-M. CONCLUSION: The presence of PVI-M was a poor prognostic factor in patients with HCC, accompanied by microscopic PVI. Anatomical resection is recommended in these patients with HCC. Patients with HCC and PVI-M may also be good candidates for adjuvant chemotherapy.

Incidentally detected lesions on contrast-enhanced MR imaging in candidates for breast-conserving therapy: correlation between MR findings and histological diagnosis.

PURPOSE: To investigate the correlation between MR findings and the histological diagnosis of incidentally detected lesions in candidates for breast-conserving therapy. MATERIALS AND METHODS: MR images of 299 patients with breast cancer were reviewed. Incidentally detected lesions were noted in 59 of 299 (20%) patients, and a histological diagnosis was obtained in 48 of 59 (81%) patients. There were 25 benign and 23 malignant lesions. The number, size, location, morphologic character, and kinetic curve assessment of the MR findings were analyzed. Statistical analyses were performed to determine whether any differences could be observed between benign and malignant lesions. RESULTS: Lesions of over 10 mm tended to be malignant (11/16; 69%), whereas those equal or less than 5 mm tended to be benign (12/17; 71%; P < 0.05). Lesions in the same quadrant as the main lesion tended to be malignant (20/27.5; 73%), whereas those in a different quadrant tended to be benign (17.5/20.5; 85%; P < 0.001). Lesions with early peak of enhancement tended to be malignant (20/25; 80%), whereas those with persistent enhancement tended to be benign (20/23; 87%; P < 0.001). CONCLUSION: Incidentally detected lesions that are found in a different quadrant from the main lesion, are smaller than 10 mm in diameter, and show persistent enhancement on MR imaging suggest benign lesions. Therefore, patients with such lesions should avoid unnecessary surgical procedures unless lesions are proved to be malignant by cytology or biopsy.

Traumatic neuroma and recurrent lymphadenopathy after neck dissection: comparison of radiologic features.

PURPOSE: To retrospectively evaluate the ultrasonographic (US), computed tomographic (CT), and magnetic resonance (MR) imaging features that differentiate traumatic neuroma from recurrent lymphadenopathy after neck dissection. MATERIALS AND METHODS: Imaging findings of 10 patients with a traumatic neuroma and 17 with recurrent lymphadenopathy were reviewed. US and CT were performed in all patients; MR imaging was performed in 16 patients. Findings analyzed at US included the diameter of the long and short axes, the short-axis-to-long-axis ratio, and the presence of a central hyperechoic area. Findings analyzed at CT were contiguity with common or internal carotid artery, lesion location in correlation with carotid artery, and the presence of a hyperattenuating rim. Findings analyzed at MR imaging included signal intensity on T1- and T2-weighted images, the presence of ring enhancement, and the presence of a hypointense rim on T2-weighted images. RESULTS: Statistically significant differences were found between traumatic neuroma and recurrent lymphadenopathy in the short-axis-to-long-axis ratio (mean, 0.47 vs 0.72; P < .001), the short-axis diameter (mean, 5.7 vs 12.2 mm; P < .001), the presence of a central hyperechoic area (five of 10 patients [50%] vs one of 17 patients [6%]; P < .05), the frequency of contact with carotid artery (two of 10 patients [20%] vs 13 of 17 patients [76%]; P < .01), and the presence of a hypointense rim on T2-weighted MR images (three of six patients [50%] vs zero of 10 patients [0%]; P < .05). Findings in other parameters were not statistically significant. CONCLUSION: Several imaging findings can differentiate traumatic neuroma from recurrent lymphadenopathy after neck dissection.

CT and MR findings of brain aspergillosis.

CT and MR findings of a case of brain aspergillosis with histopathologic correlation are reported. On both CT and MR images, there were multiple lesions in the corticomedullary junction (CMJ) that appeared to disrupt the cortical sulci and that were not enhanced by intravenous contrast material. In most of these lesions, there were centrally located structures that were enhanced by intravenous contrast material and that appeared to be continuous from markedly enhanced adjacent dilated cortical vessels. Histopathologic examination of the autopsy specimen showed multiple hemorrhagic infarcts in the CMJ with remaining dilated cortical vessels that had been thrombosed by aspergillus hyphae.

Salivary gland tumors: diagnostic value of gadolinium-enhanced dynamic MR imaging with histopathologic correlation.

PURPOSE: To evaluate the diagnostic value of gadolinium-enhanced dynamic magnetic resonance (MR) imaging of salivary gland tumors and correlate the MR imaging and histopathologic findings. MATERIALS AND METHODS: Thirty-three salivary gland tumors in 29 patients were examined preoperatively at gadolinium-enhanced dynamic MR imaging. There were 22 benign and 11 malignant tumors. Dynamic contrast material-enhanced MR images were obtained for 5 minutes. Time of peak enhancement (T(peak)) and washout ratio (WR) were determined from time-signal intensity curves (TICs). Microvessel count and cellularity-stromal grade were evaluated histopathologically. The strengths of correlations between T(peak) and microvessel count and between WR and cellularity-stromal grade were statistically analyzed. Statistical analysis was also performed to determine whether any differences among the various histopathologic tumor types existed [corrected]. In a validation study, 13 salivary gland tumors in 13 patients were examined consecutively. RESULTS: At a T(peak) of 120 seconds, malignant tumors could be differentiated from pleomorphic adenomas but not from Warthin tumors. A WR of 30%, however, enabled differentiation between malignant and Warthin tumors. Classification of TICs on the basis of a T(peak) of 120 seconds and a WR of 30% had high sensitivity (91%) and specificity (91%) in the differentiation of benign and malignant tumors. Correlations between T(peak) and microvessel count (P <.0001, rho = -0.800) and between WR and cellularity-stromal grade (P =.0105, rho = 0.572) were significant. The validation study also yielded high sensitivity (100%) and specificity (80%) in the differentiation between benign and malignant tumors. CONCLUSION: Gadolinium-enhanced dynamic MR imaging is useful for differentiating benign from malignant salivary gland tumors.

CT and MR features of nasopharyngeal carcinoma in children and young adults.

AIM: To clarify CT and MR features of nasopharyngeal carcinoma (NPC) in children and young adults. METHOD: CT and MR findings of 13 patients (30 years old or younger) with a histopathologic diagnosis of NPC were reviewed. RESULTS: Skull base invasion (12/13), lymphadenopathy (10/13), and infiltrative growth (8/8) were common findings. The signal intensity of tumours was slightly higher than that of muscles in six cases and isointense to that of muscles in two cases on T1-weighted images; it was higher than that of muscle and lower than that of cerebellar grey matter on T2-weighted images in all cases. Internal signals were homogeneous in both pre- and post-Gd-enhanced MR images in all cases. CONCLUSIONS: Despite its rarity in this age group, NPC should be included in a differential diagnosis when CT and MR imaging reveal these features.