SUVmax-to-HU ratio in diagnosis of hepatic metastases of colon cancer on FDG PET/CT. A new semiquantitative parameter.

PURPOSE: We aimed to use new semiquantitative parameter, maximum standardized uptake value (SUVmax)-to-Hounsfield unit density (HU) ratio for differentiation of colonic adenocarcinoma metastases from normal liver parenchyma on fluorine- 18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) fusion images. MATERIALS AND METHODS: We retrospectively evaluated 18F-FDG PET/CT images of 97 liver metastases from colonic adenocarcinoma in 32 adult patients. SUVmax-to-HU ratios of the metastases and non-lesion areas were calculated and compared. The correlation between SUVmax-to-HU ratio and the volume of the metastases was evaluated. Total lesion glycolysis (TLG) was obtained and correlated with SUVmax-to-HU ratios. RESULTS: The mean SUVmax, HU and SUVmax-to-HU ratio of liver metastases were significantly different than those of the normal liver parenchyma (p<0.05). There was significant correlation between SUVmax-to-HU ratios and volumes of the metastatic lesions (r=0.471, p=0.006). The correlation between TLG and SUVmax-to-HU ratio of the liver metastases was statistically significant (r=0.712, p=0.000). CONCLUSION: SUVmax-to-HU ratio is a useful parameter in differentiating liver metastases of colonic adenocarcinoma from normal liver parenchyma on 18F-FDG PET/CT images which will be helpful for staging of colonic cancer. KEY WORDS: Colonic Neoplasms, Liver, Neoplasm Metastasis, Positron-Emission Tomography, Tomography, X-Ray Computed.

Cyst-to-kidney volume ratio in the sonographic diagnosis of unilateral multicystic dysplastic kidney in children.

AIMS: To evaluate the usefulness of the cyst-to-kidney volume ratio determined by ultrasonography (US) in unilateral multicystic dysplastic kidney (MCDK) in children. MATERIAL AND METHODS: Our study group included 21 children (average age: 431 days) with unilateral MCDK and 22 children (average age: 440 days) with unilateral grade IV hydronephrosis due to ureteropelvic junction obstruction as the control group. All the children underwent transabdominal US. In children with MCDK, we calculated cyst-to-kidney volume ratios (volume of the largest cyst/volume of the MCDK) and in the control group the volume ratios of the renal pelvis and the largest calyx (volume of the pelvis or largest calyx/volume of the ipsilateral hydronephrotic kidney). Ellipsoid formula was used to calculate kidney and pelvis volumes. Sphere volume formula was used to calculate the largest cyst and calyx volumes. RESULTS: The mean cyst-to-kidney volume ratio (0.38±0.21) was significantly higher than the mean volume ratios of the renal pelvises (0.10±0.05) and the largest calyces (0.04±0.02) (p<0.05). There was no significant correlation between cyst-to-kidney volume ratio and the ages of the children (r=0.141, p=0.541). CONCLUSIONS:  With the aid of both the qualitative sonographic criteria and the newer data that we have proposed, US is a useful tool in the initial diagnosis of MCDK and for differentiation of MCDKs from grade IV hydronephrotic kidneys in children. The cyst-tokidney volume ratio is independent of age and thus, it can be helpful in the diagnosis of unilateral MCDK at any age.

Initial Fludeoxyglucose (18F) Positron Emission Tomography-Computed Tomography (FDG-PET/CT) Imaging of Breast Cancer - Correlations with the Primary Tumour and Locoregional Metastases.

BACKROUND: We aimed to evaluate initial PET/CT features of primary tumour and locoregional metastatic lymph nodes (LNs) in breast cancer and to look for potential relationships between several parameters from PET/CT. MATERIAL/METHODS: Twenty-three women (mean age; 48.66±12.23 years) with a diagnosis of primary invasive ductal carcinoma were included. They underwent PET/CT imaging for the initial tumour staging and had no evidence of distant metastates. Patients were divided into two groups. The LABC (locally advanced breast cancer) group included 17 patients with ipsilateral axillary lymph node (LN) metastases. The Non-LABC group consisted of six patients without LN metastases. PET/CT parameters including tumour size, axillary LN size, SUVmax of ipsilateral axillary LNs (SUVmax-LN), SUVmax of primary tumour (SUVmax-T) and NT ratios (SUVmax-LN/SUVmax-T) were compared between the groups. Correlations between the above-mentioned PET/CT parameters in the LABC group as well as the correlation between tumour size and SUVmax-T within each group were evaluated statistically. RESULTS: The mean values of the initial PET/CT parameters in the LABC group were significantly higher than those of the non-LABC group (p<0.05). The correlation between tumour size and SUVmax-T value within both LABC and non-LABC groups was statistically significant (p<0.05). In the LABC group, the correlations between the size and SUVmax-LN values of metastatic axillary LNs, between tumour size and metastatic axillary LN size, between SUVmax-T values and metastatic axillary LN size, between SUVmax-T and SUVmax-LN values, and between tumour size and SUVmax-LN values were all significant (p<0.05). CONCLUSIONS: We found significant correlations between PET/CT parameters of the primary tumour and those of metastatic axillary LNs. Patients with LN metastases had relatively larger primary tumours and higher SUVmax values.

Detection of retroaortic left renal vein and circumaortic left renal vein by PET/CT images to avoid misdiagnosis and support possible surgical procedures.

OBJECTIVE: We aimed to identify retroaortic left renal vein (RLRV) and circumaortic left renal vein (CLRV) by using positron emission tomography/computed tomography (PET/CT) images, to obtain their percentages and to evaluate the effect of gender on their frequencies. MATERIALS AND METHODS: Plain CT and fluorine-18-2-fluoro-2-deoxy-D-glucose PET/CT images of 222 consecutive patients who underwent oncological PET/CT imaging were used to detect RLRV and CLRV. The numbers and percentages of total left renal vein (LRV) variations, RLRV and CLRV were obtained. Fisher's exact test was used to determine the relation between the LRV variations and gender. RESULTS: In the whole group (n=222), the percentages and the numbers of total LRV variations, RLRV and CLRV were 5.85% (n=13), 2.70% (n=6) and 3.15% (n=7), respectively. In male population (n=116), the percentages and the numbers of total LRV variations, RLRV, and CLRV were 6.03% (n=7), 2.58% (n=3) and 3.45% (n=4), respectively. In female population (n=106), the percentages and the numbers of total LRV variations, RLRV, and CLRV were 5.66% (n=6), 2.83% (n=3) and 2.83% (n=3), respectively. The percentages of RLRV and CLRV were found to be independent of gender (P=1.000). CONCLUSION: PET/CT is a useful imaging modality in detecting RLRV and CLRV. The relationship of gender with RLRV or CLRV was not statistically significant.

Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET/CT) Findings in an Unusual Case of Multiple Myeloma Presenting with a Large Extra-Axial Intracranial Mass.

BACKGROUND: We aimed to present unusual cranial FDG PET/CT findings of a 56-year-old female with multiple myeloma (MM). CASE REPORT: Plain CT images revealed a lytic lesion in the right parietal bone, filled with an oval-shaped, large, extra-axial, extradural, intracranial mass which measured 75×75×40 mm and had smooth borders. The right parietal lobe was compressed by the mass. The maximum standardized uptake value (SUVmax) of the mass lesion was 8.94 on FDG PET/CT images. Multiple lytic lesions with an increased uptake were also detected in other calvarial bones, in several vertebras and in the proximal left femur. After seven months, a control FDG PET/CT following radiotherapy and chemotherapy revealed almost complete regression of the right parietal extra-axial mass lesion. The number, size and metabolism of lytic lesions in other bones also decreased. CONCLUSIONS: FDG PET/CT was useful for an initial evaluation of MM lesions and was effective in monitoring the response of these lesions to therapy.

The use of ultrasonography in infantile hypertrophic pyloric stenosis: does the patient's age and weight affect pyloric size and pyloric ratio?

AIMS: We aimed to obtain pyloric measurements of our patients with infantile hypertrophic pyloric stenosis (IHPS) using ultrasonography (US) and to evaluate the correlations between age, weight and pyloric size, pyloric ratio (PR). MATERIAL AND METHODS: We designed a retrospective study including 20 term infants with surgically proven IHPS and studied the ultrasonographically obtained pyloric muscle thickness (PMT), pyloric diameter (width) (PD), pyloric length (PL) and PR (PMT/PD) to determine if there were statistically significant associations between patient age/weight and pyloric measurements. RESULTS: The mean age of the infants was 38.7+/-17.3 days (range, 9-76 days) and their mean weight was 3688.5+/-772.7 g (range, 2810-6000 g), at referral. Mean PMT was 4.98+/-1.04 mm (range, 3.5-6.8 mm). Mean PD was 14.04+/-2.39 mm (range, 10-18 mm). Mean PL was 22.16+/-4.02 mm (range, 16-31.5 mm) and mean PR was 0.35+/-0.04 (range, 0.29-0.42). The correlation between age and PMT (r=0.654, p<0.05) and the correlation between age and PD (r=0.747, p <0.05) were significant. Age and weight were not significantly correlated with PR (p>0.05). CONCLUSIONS: The PMT and PD are age dependent parameters. The PR is age and weight independent and therefore, when combined with PMT, PD and PL, it can be useful in the diagnosis of IHPS in infants with early onset disease and/or in those with a lower weight.

Ultrasonographic and scintigraphic findings of thyroid hemiagenesis in a child: report of a rare male case.

Thyroid hemiagenesis is a rare congenital anomaly in which one lobe of thyroid gland fails to develop. It is much rarer in males. There is a higher incidence of associated thyroid disorders in patients with thyroid hemiagenesis; therefore early and prompt diagnosis is important for children. We present the ultrasonographic and scintigraphic findings of thyroid hemiagenesis in an eight-year-old-boy. On ultrasonography (US), left lobe of the thyroid gland could not be demonstrated and the right lobe showed minimal hyperplasia. Its echogenicity was normal and no nodule was seen. On thyroid scintigraphy, left lobe of thyroid gland or any ectopic thyroid tissue could not be demonstrated, while the right lobe showed minimal hyperplasia. Without performing any invasive procedure, we enrolled the child in a follow-up program with the guidance of US and scintigraphy, which were effective both in making the final diagnosis of thyroid hemiagenesis and in evaluating the current status of the present thyroid tissue. In conclusion, if only one thyroid lobe is detected in a pediatric case initially with US or scintigraphy, the diagnosis of thyroid hemiagenesis should be suggested and, before any unnecessary or invasive attempt, the other complementary method (scintigraphy/US) should be performed.

Ultrasonographic evaluation of ureteral stones in children: can we use stone width as a predictor of spontaneous passage?

AIMS: We aimed to obtain the maximum transverse diameters (widths) of ultrasonographically detectable ureteral stones in children and to evaluate the effect of widths on the rate of spontaneous discharge and on the degree of ipsilateral hydronephrosis. MATERIAL AND METHODS: We retrospectively evaluated 52 ultrasonographically detected ureteral stones in 51 consecutive patients (32 males, 19 females) with a median age of 9 years (range, 6 months-17 years). RESULTS: In group 1, in which the stones passed spontaneously (n=29), sonographically measured median and mean widths of ureteral stones were 3.8 mm (range, 2.3-7.3 mm) and 4.1+/-1.3 mm, respectively. In group 2, in which the stones required surgical procedures (n=23), median and mean widths were 5.9 mm (range, 3.9-10.0 mm) and 5.9+/-1.8 mm, respectively. The difference between widths in group 1 and group 2 was significant (p=0.001). With regard to the whole study group (n=52), the majority of the stones below 4.0 mm (88.9%, n=16/18) were passed spontaneously and 2/3 of the stones above 5.0 mm required intervention (66.7%, n=12/18). The width range of 4.0-5.0 mm can be accepted as "range of transition" for spontaneous passage and surgical procedures. The stone width was different in patients with mild and severe pelvicaliectasis (p=0.0001). CONCLUSIONS: In children, measuring the width of an ultrasonographically detectable ureteral stone can be useful for assessing its possibility to be passed spontaneously. Pelvicaliectasis should be an alerting sign for the presence of an occult ipsilateral ureteral stone in a symptomatic patient.

Evaluation of the effects of recipient/donor gender on early/late postoperative renal graft functions by renal scintigraphy.

OBJECTIVES: We discuss the effects of recipient/donor gender on renal allograft functions using scintigraphic parameters obtained 3 days after renal transplant and 1 year after transplant. MATERIALS AND METHODS: This retrospective study included 76 renal allograft recipients (group one, 38 males; group two, 38 females). Patients underwent scintigraphic imaging with Tc-99m DTPA on postoperative day 3 and 1 year after transplant. We used the Hilson perfusion index, maximum renal activity/background activity, ratio of renal activity at 20 minutes to renal activity at 3 minutes, time-to-peak activity, and glomerular filtration rate to measure quantitative parameters. RESULTS: On postoperative day 3, the Hilson perfusion index, maximum renal activity/background activity, the ratio of renal activity at 20 minutes to renal activity at 3 minutes, time-to-peak activity, and glomerular filtration rate values for male/female recipients were similar (P = .65, P = .77, P = .38, P = .10, P = .99). The gender of donors was compared with the above-mentioned scintigraphic parameters of the recipients, and no statistically significant differences were found (P = .24, P = .25, P = .44, P = .29, P = .13). At 1-year follow-up, values obtained from group 1 and group 2 recipients were similar. After 1 year, chronic rejection developed in 15.7% of group 1 recipients and in 10.5% of group 2 recipients; acute rejection developed in 21% of group 1 recipients and in 23.6% of group 2 recipients. There were no statistically significant differences between the occurrence of acute rejection and the gender of recipients or donors (P = 1.00, P = .45). CONCLUSIONS: We observed no statistically significant differences between renal graft functions and gender of the recipients/donors during the early/late posttransplant period.

Wandering spleen in a child with symptoms of acute abdomen: ultrasonographic diagnosis. Case report.

We report the initial and follow-up ultrasonography (US) findings in a pediatric case of wandering spleen with symptoms of acute abdomen, as a rare entity. A four-year-old boy was referred with complaints of blunt abdominal pain, vomiting and fatigue. US detected an oval- shaped, mildly enlarged spleen with inferomedial displacement. In right lateral decubitus, the spleen showed further medial displacement. Five months later, control US revealed further enlargement of the displaced spleen. Seven months later, due to acute torsion of the spleen, splenectomy was performed.

Computed tomography and magnetic resonance imaging findings in a case with biliary microhamartomas.

Biliary microhamartomas, also known as bile duct hamartomas and von Meyenburg complexes, are benign neoplasms containing cystic dilated bile ducts embedded in fibrous stroma. They develop in hepatobiliary system, do not generally give clinical outcomes, and are detected incidentally. However, they can rarely show malignant transformation. Our aim was to report the contribution of computed tomography, routine magnetic resonance imaging, and magnetic resonance cholangiopancreatography in the diagnosis of biliary microhamartomas in a 61-year-old woman.

Ultrasonographic findings of intussusception in pediatric cases.

PURPOSE: We aimed to characterize, by ultrasonography (US), the aspects, locations and the dimensions of intussusceptions in pediatric cases and to compare these data with the clinical findings and therapeutical outcomes. MATERIALS AND METHODS: We retrospectively evaluated abdominal US examinations and clinical data of 13 consecutive pediatric patients with intussusceptions. Patients are grouped according to the type of intussusceptions (ileocolic intussusceptions and intussusceptions with colocolic involvement) and according to the modality of treatment (surgical and non-surgical). RESULTS: Median age was 24 months (range 5-108 months). Eleven cases were surgically treated because of delayed referral. For all cases the mean diameter+/-SD of intussusception was 30+/-5 mm and mean length+/-SD was 59+/-21 mm. For ileocolic intussusceptions (n=9/11), mean diameter+/-SD was 29.1+/-4.4 mm and mean length+/-SD was 61.7+/-18.1 mm. The right upper quadrant of abdomen was the most common location for ileocolic intussusceptions (n=7/9), the rest were located in paraumbilical regions (n=2/9). For two cases of intussusceptions with colocolic involvement (ileocolocolic and colocolic intussusceptions located in right upper quadrant and left lower quadrant, respectively), mean diameter+/-SD was 37.5+/-0.7 mm and mean length+/-SD was 75.5+/-21.9 mm. The difference between mean diameters of ileocolic intussusceptions and intussusceptions with colocolic involvement was statistically significant (p =0.03), whereas the difference between mean lengths of these two groups was not statistically significant (p=0.36). For surgically treated cases (n=11/13), mean diameter+/-SD of intussusception was 30.6+/-5.2 mm and the mean length +/-SD was 64.2+/-18.5 mm. For non-surgically treated cases (n=2/13), with intussusceptions located in right lower quadrant, mean diameter+/-SD of intussusception was 27+/-4.2 mm and the mean length+/-SD was 32.5+/-10.6 mm. The difference between mean diameters of surgically and non-surgically treated cases was not statistically significant (p=0.37), whereas the difference between mean lengths of these two groups was statistically significant (p=0.04). CONCLUSIONS: A very good correlation between US and surgical findings was obtained. US should be used in all pediatric patients clinically suspected for intussusception. A relatively large, target-like and sandwich-like, incompressible intraabdominal bowel mass having the above mentioned dimensions should be looked for on US examination.