Patient dose in brain perfusion imaging using an 80-slice CT system.

BACKGROUND AND PURPOSE: Brain CT Perfusion (CTP) is an X-ray imaging technique for the assessment of brain tissue perfusion, which can be used in several different entities. The aim of this study is the evaluation of the radiation dose to patients during a comprehensive brain CT prescription protocol (CPP) consisting of an unenhanced brain CT, a brain CT angiography and a CTP scan. MATERIALS AND METHODS: Eighteen patients were studied using an 80-slice CT system, with an iterative reconstruction algorithm. The volume Computed Tomography Dose Index (CTDIvol) and dose length product (DLP) were recorded from the dose report of the system. The calculation of effective dose (ED) was accomplished using the DLP values. RESULTS: For the CTP examinations, the CTDIvol ranged from 116.0 to 134.8mGy, with the mean value 119.5mGy. The DLP ranged from 463.9 to 539.2mGy·cm, with the mean value 478mGy·cm. For the CPP, the total ED ranged from 3.31 to 5.07mSv, with the mean value 4.37mSv. CONCLUSIONS: These values are lower than the values reported in corresponding studies, including studies utilizing CT systems with more slices.

Computed tomography cephalometric and upper airway measurements in patients with OSA and erectile dysfunction.

PURPOSE: Erectile dysfunction (ED) has been linked to obstructive sleep apnea (OSA). This study used computed tomography (CT) to identify cephalometric and upper airway anatomic features in patients with OSA that correlate with the presence of ED. METHODS: In this prospective study, 20 CT cephalometric and upper airway measurements, most commonly associated with OSA, were analyzed in 53 age- and BMI-matched consecutive eligible subjects. Twenty-two were diagnosed with OSA and ED (OSA+/ED+), 17 with OSA without ED (OSA+/ED-), and 14 without OSA and ED (OSA-/ED-) serving as a control group. RESULTS: Although OSA+/ED+ did not differentiate significantly in CT measurements from OSA+/ED-, they showed more alterations when compared to OSA-/ED-, which included narrower bony oropharynx, longer soft palate and uvula (PNS-P), and narrower retropalatal and retrolingual airway diameter (p < 0.05). Binary forward stepwise model analysis showed that PNS-P was the only significant variable in the predictive model for ED in patients with OSA (OR = 1.129, 95 % CI = 1.0005-1.268, p = 0.041). In the OSA+/ED+ group, PNS-P correlated with the percentage of total sleep time with oxygen saturation <90 % (r = 0.61, p < 0.01) and was the only determinant in the relevant predictive model (n = 22, model R = 0.612, adjusted R (2) = 0.337, F = 10.167, p < 0.005). CONCLUSIONS: Characteristics of the craniofacial and upper airway structures suggest that a longer soft palate and uvula may be important risk factors for the concurrence of ED in patients with OSA. Only OSA+/ED+ showed significant narrowing in the retropalatal, retrolingual, and bony oropharynx level when compared with BMI-matched OSA-/ED-.

The impact of Platelet Rich Plasma (PRP) in osseointegration of oral implants in dental panoramic radiography: texture based evaluation.

PURPOSE: In this study the temporal texture differentiation associated with the bone formation properties, around loaded oral implants after Platelet Rich Plasma (PRP) employment, was investigated in Panoramic Radiographs. MATERIALS AND METHODS: Thirty eligible patients are randomly assigned to two groups. The test group received PRP application around new implants, while in the control group no PRP treatment was made. The bone-to-implant contact region was analyzed in a clinical sample of 60 Digitized Panoramic Radiographs, 30 corresponding to immediate implant loading (Class-I) and 30 after an 8 month follow-up period (Class-II). This region was sampled by 1146 circular Regions-of-Interest (ROIs), resulting from a specifically designed segmentation scheme based on Markov-Random-Fields (MRF). From each ROI, 41 textural features were extracted, then reduced to a subset of 4 features due to redundancy and employed as input to Receiver-Operating-Characteristic (ROC) analysis, to assess the textural differentiation between two classes. RESULTS: The selected subset, achieved Area-Under-Curve (AUC) values ranging from 0.77-0.81 in the PRP group, indicating the significant temporal textural differentiation has been made. In the control group, the AUC values ranged from 0.56-0.68 demonstrating lesser osseo integration activity. CONCLUSION: This study provides evidences that PRP application may favor bone formation around loaded dental implants that could modify the dental treatment planning.

Myelotoxicity as a prognostic factor in patients with advanced breast cancer treated with chemotherapy: a pooled analysis of two randomised trials conducted by the Hellenic Cooperative Oncology Group.

BACKGROUND: A number of studies have shown that absence of myelotoxicity during chemotherapy is associated with worse outcome for various types of cancer, including carcinoma of the breast. The aim of this study was to determine whether myelosuppression in patients being treated with chemotherapy for advanced breast cancer has an impact on their prognosis. PATIENTS AND METHODS: A retrospective review was conducted of a series of 475 patients with advanced breast cancer enrolled in two randomised trials, who received first-line chemotherapy. The impact of severe (grade 3 or 4) hematological toxicity on survival and time to disease progression was assessed. RESULTS: When severe myelotoxicity was evaluated as a whole, a significant negative association for time to disease progression and a trend for a worse survival were demonstrated. In multivariate analysis, hematological toxicity retained its significance as an independent negative prognostic factor for time to disease progression. CONCLUSION: Our findings do not confirm the results of previous studies which have demonstrated a better outcome for patients experiencing hematological toxicity during treatment.

Clinical and radiological evaluation of patients with lytic, mixed and sclerotic bone metastases from solid tumors: is there a correlation between clinical status of patients and type of bone metastases?

PURPOSE: To investigate the association between the clinical status of patients with metastatic bone disease and the type of bone metastases. PATIENTS AND METHODS: 80 patients with skeletal metastases underwent both clinical and radiological assessments. Bone lesions were evaluated with computed tomography (CT), and patients were separated into three groups: lytic, mixed, sclerotic. Bone density of each lesion was measured in Hounsfield units (HU). RESULTS: Patients with osteolytic lesions had the highest mean pain score with 8.1 +/- 2.2 points, the least mean scores for quality of life (QoL) and performance status (PS) with 31.4 +/- 14.6 and 58.6 +/- 9.7 points respectively, the highest percentage and mean opioid consumption (100% and 220.9 mg of oral daily morphine equivalent respectively), and the least mean bone density (116.3 +/- 40.4 HU). On the contrary, the group with sclerotic metastases had the least mean pain score with 4.6 +/- 1.3 points, the highest mean scores of QoL and PS (61.1 +/- 15.5 and 66.6 +/- 10 points respectively), the least percentage and mean opioid requirement (55.5% and 170.6 mg respectively), and the highest mean bone density (444 +/- 86.6 HU). The differences between the three groups were statistically significant for all parameters evaluated, apart from performance status between the sclerotic and mixed groups. The correlation coefficients were statistically significant between all parameters investigated. Bone density had a strong negative correlation with pain. CONCLUSION: Our results show a clear correlation between the type of bone metastases and the clinical status of patients. Patients with excessive bone resorption suffer the most, and may be given priority in treatment. CT proved to be a practical and efficient method to investigate and classify metastatic bone lesions.

Paclitaxel-Coated Balloons for the Treatment of Dysfunctional Dialysis Access. Results from a Single-Center, Retrospective Analysis.

PURPOSE: To investigate the safety and effectiveness of lutonix paclitaxel-coated balloon (PCB) for the treatment of dysfunctional dialysis access. MATERIALS AND METHODS: This was a single-center, single-arm, retrospective analysis of 39 patients (23 male, 59 %) undergoing 61 interventions using 69 PCBs in a 20-month period. There was a balance between arteriovenous fistulae (AVF) and grafts (AVG) (20 AVFs, 19AVGs), and the majority of lesions were restenotic (25/39, 64.1 %). Mean balloon diameter used was 6.6 mm and length 73.4 mm. Primary outcome measure was target lesion primary patency (TLPP) at 6 months, while secondary outcome measures included factors affecting TLPP and major complications. As there were lesions treated more than once with PCB, authors also compared patency results after first and second PCB angioplasty. RESULTS: TLPP was 72.2 % at 6 months with a median patency of 260 days according to the Kaplan-Meier survival analysis. No major complications occurred. TLPP between AVFs and AVGs (311 vs. 237 days, respectively; p = 0.29) and de novo and restenotic lesions was similar (270.5 vs. 267.5 days, respectively; p = 0.50). In 14 cases, in which lesions were treated with two PCB angioplasties, a statistically significant difference in TLPP after the second treatment was noted (first intervention 179.5 days vs. second intervention 273.5 days; p = 0.032). CONCLUSION: In this retrospective analysis, Lutonix PCB proved to be safe and effective in treating restenosis in dysfunctional dialysis access with results comparable to the literature available. Larger studies are needed to prove abovementioned results.

A case of hepatocellular carcinoma arising within large focal nodular hyperplasia with review of the literature.

Focal nodular hyperplasia (FNH) is a relatively rare benign hepatic tumor, usually presenting as a solitary lesion; however, multiple localizations have also been described. The association of FNH with other hepatic lesions, such as adenomas and haemangiomas has been reported by various authors. We herein report a case of a hepatocellular carcinoma arising within a large focal nodular hyperplasia, in a young female patient.

Multidetector computed tomography versus platelet/spleen diameter ratio as methods for the detection of gastroesophageal varices.

BACKGROUND: All patients with liver cirrhosis should undergo screening endoscopy, but there are limitations and this approach places a heavy burden upon endoscopy units. The aim of this study was to compare multidetector computed tomography (MDCT) and the platelet/spleen diameter ratio as non-invasive methods for the detection of gastroesophageal varices. METHODS: The study included 38 cirrhotics who underwent upper gastrointestinal (GI) endoscopy and MDCT within one month. Two radiologists reviewed the scans, in order to determine the presence and the size of varices. Blood tests and measurement of the spleen maximum diameter were also carried out and the platelet/spleen diameter ratio was calculated. Endoscopy was considered the gold standard and the results of the two methods were compared to it. RESULTS: Varices were detected by upper GI endoscopy in 24 of 38 patients. The mean sensitivity and specificity of MDCT for the two observers was 86.1% and 57.1% respectively. In patients with large varices (>5 mm), the sensitivity was 100% (4/4). Using 909 as a cut-off value of the platelet/spleen diameter ratio this method yielded a sensitivity of 56.5% and a specificity of 35.7%. The difference in sensitivity and specificity between the two methods was statistically significant P<0.05. CONCLUSION: MDCT was accurate for the detection of gastroesophageal varices, especially those with clinically significant size (>5 mm), and superior to platelet/spleen diameter ratio. MDCT could replace, in selected patients, upper GI endoscopy as a method for detecting gastroesophageal varices in cirrhotic patients.

Virtual endoscopy in renal artery stenosis: an innovative approach for diagnosis and follow-up.

PURPOSE: We investigated the utility of virtual endoscopy (VE) as a diagnostic and follow-up tool in patients with renal artery stenosis, especially as a means of defining vascular patency. PATIENTS AND METHODS: We performed VE in 24 patients with ostial atherosclerotic renal artery stenosis and correlated the results with those of conventional angiography. The patients were treated successfully by placement of metal stents and conventional catheter angiography and VE for patency assessment 6 and 12 months after stent insertion. RESULTS: In all patients, the stenotic segment was identified, and VE findings were concordant with those of angiography. The average degree of stenosis was estimated to be 70% +/- 20% when angiography was used and 62% +/- 15% when VE was used. After metal stent insertion, the 12-month patency rate was 83.3% (20 patients). Angiography and VE findings remained concordant during the follow-up period, but VE provided more information beyond the stenotic segment, allowing examination of the arterial lumen both cephalad and caudal to the point of obstruction. CONCLUSION: Virtual endoscopy provided a more dynamic, direct, minimally invasive approach that was equal to or better than angiography for both the verification of the vascular stenosis and the evaluation of the arterial lumen.

Ureteral metallic stents: application of virtual endoscopy for ureteral patency control.

OBJECTIVE: In the present study we have applied virtual endoscopy (VE) in patients with ureteral metallic stents as a follow-up tool study especially in the need to define ureteral patency. METHODS: We performed the suggested technique in 6 patients with malignant ureteral obstruction treated successfully by placement of Wallstent intraureteral metallic stents, and correlated the results with antegrade nephrostomography 48 hours after initial stent placement. RESULTS: In 2 patients restenosis was observed, and in the remaining 4 patients the stented ureters remained patent during the follow up evaluation. VE and antegrade nephrostomography, were concurrent as to their findings. Moreover, VE proceeds beyond the stenotic segment, allowing visualization of the ureteral lumen both cephalad and caudal to the point of obstruction. CONCLUSION: VE is providing indeed a more accurate, direct and dynamic approach in the evaluation of a strictured ureteral lumen within the metallic stent.

Correlation of ultrasound-estimated bladder weight to urodynamic diagnoses in women with lower urinary tract symptoms.

OBJECTIVE: To test the hypothesis that the ultrasound-estimated bladder weight (UEBW) will correlate with the urodynamic diagnoses in women with lower urinary tract symptoms, in particular, detrusor underactivity and bladder outflow obstruction. Ultrasonography has been increasingly used in the assessment of lower urinary tract conditions. METHODS: Adult women referred to the urodynamics suite for investigation of lower urinary tract symptoms were enrolled. After urodynamic evaluation, the portable BladderScan BVM 6500 device was used to calculate the bladder wall thickness and UEBW according to a standardized protocol. The patients were categorized according to the urodynamic findings. Women with normal findings, despite the symptoms for which they were referred, were used as the control group. The UEBW and bladder wall thickness measurements were compared between the groups and controls, using the Mann-Whitney and Kolmogorov-Smirnov tests. P <.05 was considered statistically significant. RESULTS: A total of 187 women were enrolled. The UEBW was significantly lower in the patients with detrusor underactivity than in the controls (39.3 ± 3.0 g vs 45.7 ± 3.1 g, P <.001). Significant differences were also noted between the controls and patients with bladder outflow obstruction, with or without detrusor overactivity (45.7 ± 3.1 g vs 52.1 ± 3.9 g and 52.3 ± 6.2 g, respectively; P <.001 for both). The difference, in terms of the UEBW, between controls and patients with detrusor overactivity was not statistically significant (45.7 ± 3.1 g vs 45.3 ± 3.0, P > .05). CONCLUSION: A significantly reduced UEBW in female patients with detrusor underactivity and a significantly increased UEBW in patients with bladder outflow obstruction were found. However, the finding of a significantly increased bladder weight in patients with detrusor overactivity was not confirmed in the present study.

Management of gastrointestinal leaks after surgery for clinically severe obesity.

BACKGROUND: Gastrointestinal leaks after bariatric surgery are the primary cause of serious morbidity and mortality nationwide. Enteric leaks can differ in severity, presentation, and management, depending on the type of bariatric surgery performed. Our objective was to describe the clinical presentation and treatment outcomes in patients who developed postoperative leaks at a university hospital bariatric referral center. METHODS: A retrospective observational study using descriptive statistics was conducted on data from 1499 bariatric operations performed at our institution from 1994 to 2010. The procedures included a variant of biliopancreatic diversion with long limb reconstruction (BPD-LL) in 820 patients (791 open and 29 laparoscopic), Roux-en-Y gastric bypass (RYGB) in 301 patients (105 open and 196 laparoscopic), and sleeve gastrectomy (SG) in 208 patients (5 open and 203 laparoscopic). RESULTS: Of these patients, 30 (2%) developed a postoperative leak at a median of 18 days (range 2-32) postoperatively. The primary procedure was laparoscopic SG in 12 patients (5.8%), laparoscopic RYGB in 5 patients (1.6%), and BPD-LL (12 open and 1 laparoscopic) in 13 patients (1.6%). In all patients who underwent laparoscopic SG, the leak site was along the staple line. The gastrojejunal anastomosis was leaking in 4 (80%) and 12 (92.3%) patients in the RYGB and BPD-LL group, respectively. The enteroenteral anastomosis was leaking in 1 patient each in the RYGB and BPD-LL groups (20% and 7.7%, respectively). Three patients (10%; 2 from the BPD-LL group and 1 from the RYGB group) presented with generalized peritonitis and underwent emergency re-exploration; nonoperative treatment was successful in the remaining 27 patients (90%). Stent placement for persistent gastrocutaneous fistula was used in 9 patients (30%; 8 from the SG cohort and 1 from the BPD-LL group). The overall mortality rate was 3.3%. CONCLUSION: In our experience, most leaks resulting from antiobesity surgery were successfully managed using nonoperative methods. Rapid management of gastrointestinal leaks using computed tomography-guided drainage and/or intraluminal stent placement could be the treatment of choice in selected patients.

Anastomoses between bronchial and coronary circulation in a porcine model: computed tomographic and angiographic demonstration.

INTRODUCTION: Although the importance of the bronchial arteries is evident in modern day thoracic surgery, the significance of their communications with coronary arteries has yet to be appreciated, especially in cases of heart-lung transplantation and aortic aneurysm repair. We conducted a study to demonstrate the coronary-bronchial anastomotic routes in a porcine model using angiography and computed tomography. METHODS: Six young female white pigs were used. The heart and lungs were removed en bloc, including the lower trachea and oesophagus. Digital subtraction angiography of the bronchial circulation and spiral computed tomography scan were performed in a three-phase study before and after administration of contrast medium. This was achieved by infusion either into the cannulated bronchial artery or into the aortic root. Macroscopic evaluation was carried out using latex infusion into the bronchial or coronary circulation. RESULTS: We demonstrated communications between the bronchial and coronary systems in 5 of 6 subjects. This communication was located at the left atrial wall and the posterior and anterior wall of the left ventricle. In one case there were further anastomoses around the right atrial wall. CONCLUSIONS: There were communications between the left coronary arteries and the bronchial arteries in the majority of cases. Digital subtraction angiography and spiral computer tomography scan can demonstrate these communications directly and indirectly by measurements of contrast enhancement within the heart wall. Our study emphasises the importance of the bronchial arteries in cases of heart-lung transplantation and repair of thoracic aortic aneurysms.