Cross-sectional Computed Tomography Images Research Articles

Estimation of carcass composition and cut composition from computed tomography images of live growing pigs of different genotypes

The aim of the present work was (1) to study the relationship between cross-sectional computed tomography (CT) images obtained in live growing pigs of different genotypes and dissection measurements and (2) to estimate carcass composition and cut composition from CT measurements. Sixty gilts from three genotypes (Duroc×(Landrace×Large White), Pietrain×(Landrace×Large White), and Landrace×Large White) were CT scanned and slaughtered at 30 kg (n=15), 70 kg (n=15), 100 kg (n=12) or 120 kg (n=18). Carcasses were cut and the four main cuts were dissected. The distribution of density volumes on the Hounsfield scale (HU) were obtained from CT images and classified into fat (HU between −149 and −1), muscle (HU between 0 and 140) or bone (HU between 141 and 1400). Moreover, physical measurements were obtained on an image of the loin and an image of the ham. Four different regression approaches were studied to predict carcass and cut composition: linear regression, quadratic regression and allometric equations using volumes as predictors, and linear regression using volumes and physical measurements as predictors. Results show that measurements from whole animal taken in vivo with CT allow accurate estimation of carcass and cut composition. The prediction accuracy varied across genotypes, BW and variable to be predicted. In general, linear models, allometric models and linear models, which included also physical measurements at the loin and the ham, produced the lowest prediction errors.

A Study of the Proximal Left Anterior Descending Coronary Artery Motion

Objective: The purpose of this study is to elucidate deformation of each compression and torsion exerted to the proximal left anterior descending (LAD) artery during the cardiac cycle. Background: We hypothesised that mechanical stress exerted on the proximal LAD artery by cardiac contractions is a determinant of the need for repeat revascularization after stenting, though the proximal LAD motion has not been thoroughly studied. Methods: We prospectively analysed the electrocardiogram-gated, 64-slice multi detector row computed tomography (CT) images obtained in 297 consecutive patients suspected of suffering from coronary artery disease for having major risk factors, an abnormal electrocardiogram, or angina pectoris. Results: Using multi-planar reconstruction and enhanced cross-sectional CT images, the compression and torsion of the proximal LAD artery between end-systole and end-diastole were 15.6 ± 26.4% and 0.5 ± 0.6°/mm, respectively. The compression ratio was significantly smaller in diabetic (12.3 ± 33.8%) than in non-diabetic (16.5 ± 24.1%) patients (P<0.05). The torsion was also smaller in patients with versus without 3-vessel coronary disease (0.3 ± 0.3°/mm versus 0.5 ± 0.6°/mm; P<0.05) and in patients with versus without histories of previous valve surgery (0.2 ± 0.1°/mm versus 0.5 ± 0.6°/mm; P<0.05). Conclusions: We measured the amount of compression and torsion to the proximal LAD artery associated with the cardiac contractions. These mechanical stimuli may promote plaque rupture and progression, and in-segment restenosis after stent implantations.

Erosion of Inflatable Penile Prosthesis Reservoir into Neobladder

Erosion of the reservoir into surrounding tissues is a rare complication after inflatable penile prosthesis (IPP) implantation. To present a new case and a review of the literature including discussion of pathogenesis, risk factors, and management options. We present the case of a 75-year-old male who underwent placement of an IPP for postoperative erectile dysfunction with a history of bladder cancer requiring radical cystoprostatectomy and Studer neobladder. Six years after IPP placement, he presented with recurrent febrile urinary tract infection that seemed to be precipitated by cycling of his penile prosthesis. Cystoscopy and cross-sectional computed tomography imaging demonstrated erosion of the inflatable penile prosthesis reservoir into the neobladder. Patient underwent open removal of the IPP reservoir and cystorrhaphy with a plan for future prefascial reimplantation of an IPP reservoir. In patients with a history of abdomino-pelvic surgery or radiation therapy, the retroperitoneal space may be extremely fibrotic and the transversalis fascia may have thickened. Potential intraoperative complications as well as reservoir erosion may be avoided by using a two-piece device or ectopic reservoir placement. Management options for reservoir erosion include explantation of the entire device as well as reservoir removal with salvage of remaining components.

Evaluation of the anisotropy of the void distribution and the stiffness of lightweight aggregates using CT imaging

The void distribution in concrete materials strongly affects its material properties. Therefore, identification of the spatial void distribution is important to understand and estimate material behavior. To quantify the void distribution inside lightweight aggregates, a computed tomography (CT) image can be effective, as it is non-destructive. Here, three-dimensional void images of lightweight aggregates are generated by stacking cross-sectional CT images. The spatial distribution of voids in the aggregate along a direction is visualized on a sphere using a probability distribution function. To describe the void distribution of aggregates, a two-point correlation function is used. The stiffness of the lightweight aggregate for a direction is also examined. We find that the direction-based probability distribution and stiffness from the CT images are effective for characterizing the void distributions of aggregates. In addition, the anisotropy ratio of voids and the stiffness are closely related along with the void volume fraction.

Visualization of the superior and inferior borders of the mandibular canal: a comparative study using digital panoramic radiographs and cross-sectional computed tomography images

To evaluate the visibility of the superior and inferior borders of mandibular canal using panoramic radiography (PR) and cross-sectional computed tomography (CT) images. Digital panoramic images and cross-sectional CT images of 100 patients were evaluated. The mandibular canal was divided into 4 areas of equal width (1-4), from anterior to posterior. The visibility of the superior and inferior borders was assessed using a 5-point visibility scoring system, with lower scores for worse visibility. For both modalities, the superior border showed significantly lower score than the inferior border in all areas. For the superior border, areas 1, 2, and 3 all showed significantly lower scores than area 4 for PR, whereas only area 1 showed a lower score than area 4 for CT. The visibility of the superior border was very poor on panoramic images. The use of cross-sectional CT images remarkably improved this poor visualization.

Experimental and finite element analysis of tibial stress fractures using a rabbit model

To determine if rabbit models can be used to quantify the mechanical behaviour involved in tibial stress fracture (TSF) development. Fresh rabbit tibiae were loaded under compression using a specifically-designed test apparatus. Weights were incrementally added up to a load of 30 kg and the mechanical behaviour of the tibia was analysed using tests for buckling, bone strain and hysteresis. Structural mechanics equations were subsequently employed to verify that the results were within the range of values predicted by theory. A finite element (FE) model was developed using cross-sectional computer tomography (CT) images scanned from one of the rabbit bones, and a static load of 6 kg (1.5 times the rabbit's body weight) was applied to represent running. The model was validated using the experimental strain gauge data, then geometric and elemental convergence tests were performed in order to find the minimum number of cross-sectional scans and elements respectively required for convergence. The analysis was then performed using both the model and the experimental results to investigate the mechanical behaviour of the rabbit tibia under compressive load and to examine crack initiation. The experimental tests showed that under a compressive load of up to 12 kg, the rabbit tibia demonstrates linear behaviour with little hysteresis. Up to 30 kg, the bone does not fail by elastic buckling; however, there are low levels of tensile stress which predominately occur at and adjacent to the anterior border of the tibial midshaft: this suggests that fatigue failure occurs in these regions, since bone under cyclic loading initially fails in tension. The FE model predictions were consistent with both mechanics theory and the strain gauge results. The model was highly sensitive to small changes in the position of the applied load due to the high slenderness ratio of the rabbit's tibia. The modelling technique used in the current study could have applications in the development of human FE models of bone, where, unlike rabbit tibia, the model would be relatively insensitive to very small changes in load position. However, the rabbit model itself is less beneficial as a tool to understand the mechanical behaviour of TSFs in humans due to the small size of the rabbit bone and the limitations of human-scale CT scanning equipment. The current modelling technique could be used to develop human FE models. However, the rabbit model itself has significant limitations in understanding human TSF mechanics.

Assessment of alveolar defect volume in unilateral cleft lip and palate patients using a free software program

The purpose of this study was to assess the alveolar defect volume in unilateral cleft lip and palate (UCLP) subjects using computed tomography (CT) and a free software program to evaluate the intra- and inter-rater measurements, and to compare the cleft volume between age and affected side. The sample of this retrospective study consisted of 20 UCLP individuals, 12 boys and 8 girls, mean age 10.3 ± 2.4 years at the beginning of orthodontic treatment. All subjects required alveolar bone grafting. CT scans of the cleft area were obtained prior to secondary bone grafting, and were analyzed using Image J. software program. The cleft volume was calculated based on axial cross-sectional CT images by two raters (orthodontist and radiologist) and by the same rater (orthodontist) at two different moments. Linear mixed model, Bland-Altman, Pearson’s and intraclass correlation coefficient (ICC) were used. The mean cleft volume was 7.53 ± 1.55 mm3. The intra- and inter-rater measurements were reproducible (ICC = 0.976 and 0.963, respectively) with no significant difference between them. There were no statistically significant differences in the cleft volume related to age or cleft location. The assessment of cleft volume in UCLP using CT images and a free software program was a reproducible method. There was no significant relation between alveolar defect volume and age or cleft location.

Visceral Adipose Tissue Indicates the Severity of Cardiometabolic Risk in Patients with and without Type 2 Diabetes: Results from the INSPIRE ME IAA Study

Visceral adiposity is an important correlate of cardiometabolic risk, yet its association after the diagnosis of type 2 diabetes remains unclear. Our objective was to assess the independent and combined associations of visceral adiposity and type 2 diabetes to cardiometabolic risk. The INternational Study of Prediction of Intra-abdominal adiposity and its RElationships with cardioMEtabolic risk/Intra-Abdominal Adiposity (INSPIRE ME IAA) is a cross-sectional computed tomography imaging study with data collected from June 2006 to May 2008. General physicians, cardiologists, and diabetologists (n = 297) in 29 countries recruited 4144 (51.8% men) men (39-71 yr) and women (44-71 yr). Patients were categorized according to visceral adiposity tertiles, type 2 diabetes status, and sex. All results were adjusted for age, body mass index, region, and physician's specialty. Markers of insulin resistance, lipid/lipoproteins, inflammatory markers, and liver fat increased with visceral adiposity in men and women with and without type 2 diabetes. Prevalent cardiovascular disease increased with visceral adiposity tertiles, regardless of type 2 diabetes status. Visceral adiposity [odds ratio = 1.25 (1.09-1.44) for men and 1.78 (1.50-2.12) for women] was positively associated with type 2 diabetes, whereas liver attenuation (inversely related to liver fat) was negatively associated with type 2 diabetes [odds ratio = 0.66 (0.59-0.75) for men and 0.63 (0.55-0.72) for women]. Subcutaneous adipose tissue was inversely related to type 2 diabetes in women [0.76 (0.0.66-0.88)] and not associated with type 2 diabetes in men [0.97 (0.85-1.11)]. Visceral, but not sc, abdominal adiposity is strongly related to cardiometabolic risk factors and to the prevalence of cardiovascular disease and may be an important driver of cardiometabolic risk in patients regardless of type 2 diabetes status.

Extrahepatic biliary cancer: New staging classification

Tumor staging defines the point in the natural history of the malignancy when the diagnosis is made. The most common staging system for cancer is the tumor, node, metastases classification. Staging of cancers provides useful parameters in the determination of the extent of disease and prognosis. Cholangiocarcinoma are rare and refers to cancers that arise from the biliary epithelium. These tumors can occur anywhere along the biliary tree. These tumors have been previously divided into extrahepatic and intrahepatic lesions. Until recently the extrahepatic bile duct tumors have been considered as a single entity per American Joint Commission on Cancer (AJCC) staging classification. The most recent changes to the AJCC classification of bile duct cancers divide the tumors into two major categories: proximal and distal tumors. This practical classification is based on anatomy and surgical management. High quality cross-sectional computed tomography (CT) and/or magnetic resonance (MR) imaging of the abdomen are essential information to accurately stage this tumors. Imaging plays an important role in diagnosis, localization, staging and optimal management of cholangiocarcinoma. For example, it helps to localize the tumor to either perihilar or distal bile duct, both of which have different management. Further, it helps to accurately stage the disease and identify the presence of significant nodal and distant metastasis, which may preclude surgery. Also, it helps to identify the extent of local invasion, which has a major impact on the management. For example, extensive involvement of hepatic duct reaching up to second-order biliary radicals or major vascular encasement of portal vein or hepatic arteries precludes curative surgery and patient may be managed by palliative therapy. Further, imaging helps to identify any anatomical variations in the hepatic arterial or venous circulation and biliary ductal system, which is vital information for surgical planning. This review presents relevant clinical presentation and imaging acquisition and presentation for the accurate staging classification of bile duct tumors based on the new AJCC criteria. This will be performed with the assistance of anatomical diagrams and representative CT and MR images. The image interpretation must include all relevant imaging information for optimum staging. Detailed recommendations on the items required on the radiology report will be presented.

Pneumothorax in a Single Lung Patient

An 80-year old man referred to the emergency department for chest pain and dyspnea on exertion reported a medical history of left pulmonary tuberculosis in babyhood, treated by therapeutic pneumothorax. This was commonly used to treat tuberculosis prior to the development of antimycobacterial agents. Successful therapeutic pneumothorax resulted in fibrosis and encapsulation of the diseased lung and containment of the infection. Forty-eight hours prior to admission, he underwent chest trauma caused by a staircase fall. Physical examination revealed extensive subcutaneous emphysema of the chest, neck and arms. Thoracic computed tomography unexpectedly revealed a single right lung expanded through the entire thorax cavity, a partial anterior pneumothorax (Figure), a fracture of the ninth right rib and extensive soft tissue emphysema. Left lung was hypoplastic in posterior position. As a consequence, mediastinum was fully shifted in left posterior position. Pneumothoraces due to trauma usually require the placement of a chest tube.1 In this case of limited anterior pneumothorax, insertion of a chest tube was not indicated, and the patient spontaneously recovered in a few days. Figure. Cross-sectional computed tomography image of the pneumothorax

Computed Tomography and Magnetic Resonance Features of Gliosarcoma

To investigate the features of pathologically confirmed gliosarcomas using computed tomography (CT) and magnetic resonance (MR) imaging. We retrospectively reviewed the cross-sectional CT and MR images of 54 patients (37 males and 17 females; mean age, 44.5 years; range, 13-74 years) with gliosarcomas confirmed by histopathology. Across all patients, there were 59 lesions. On nonenhanced CT and MR images, tumors were predominantly inhomogeneous. On the postcontrast CT and MR images, 50 (84.7%) irregular lesions had thick walls with a strong rim- and ringlike enhancement, whereas the remaining 9 (15.3%) round or oval lesions had even thin walls with an enhanced peripheral ring. Magnetic resonance spectroscopy showed increased choline and lactate values, along with decreased N-acetylaspartate and creatine values. On diffusion-weighted imaging, the tumor was slightly or markedly hyperintense compared with the white matter. A well-demarcated mass located peripherally, with rimlike or ring enhancement, is a common presentation of gliosarcoma on CT and MR images. In addition, magnetic resonance spectroscopy and diffusion-weighted imaging can be used to make a differential diagnosis.

Splenic Volume Can Be a Novel Predictive Parameter for the Prognosis of Chronic Lymphocytic Leukemia?

AbstractAbstract 4623Recently, clinical importance of disease status by computed tomography (CT) before treatment in chronic lymphocytic leukemia (CLL) is increasing. The present study was conducted to evaluate whether splenic volume (SV) by CT would predict the clinical outcome in CLL patients.SV were measured in 61 Rai II-IV CLL patients who underwent CT scan before chlorambucil therapy. SV was reconstructed and measured from the cross-sectional CT images by using 3 dimensional Voxar analytical volume software.Median SV was 721.3 cm3 (223.7-3576.6 cm3) is the most significant separated cut-off point on progression-free survival (PFS) and overall survival (OS). Low SV group was associated with longer PFS and OS than high SV group (p<0.001; p<0.001). High SV (SV ≥ 721.3 cm3) was associated with higher Rai stage (SV between Rai II and III, p=0.005; Rai III and IV, p=0.026) and poorer response (SV between CR and PR, p=0.075; PR and SD, p=0.366; SD and PD, p=0.019). Univariate and multivariate analyses revealed that high SV was independent prognostic factor on PFS (HR, 2.924; 95%CI, 1.308–6.538; p=0.009) and OS (HR, 3.024; 95%CI, 1.106–8.270; p=0.031).SV before therapy reflected the clinical outcome in CLL patients. Disclosures:No relevant conflicts of interest to declare.

Wandering Epidural Catheter

Massachusetts General Hospitaljc.brookman.md@gmail.comA MALE patient, 73 yr old, had a Flexitip Plus® (Arrow International, Reading, PA) 19-gauge end-hole, wire-reinforced thoracic epidural catheter inserted for postthoracotomy pain management. He underwent high-resolution spiral computed tomography scan with the catheter in situ before its use to evaluate previous bronchoscopic findings. A composite set of sagittal computed tomography images (figs. A and B) show two- and three-dimensional thoracic spine reconstructions that highlight the track of the epidural catheter in this patient. FigureA shows a three-dimensional reconstruction of the spine sliced down midline, looking toward the right with the catheter looped away from the viewer, and resting adjacent to the pedicle (bold arrow). FigureB is a two-dimensional cross-sectional computed tomography image demonstrating the course of the epidural catheter from outside the skin to within the epidural space, with anterolateral placement of the catheter tip terminating adjacent to the pedicle (circles). The catheter first loops into the anterior and then back into the lateral epidural space terminating adjacent to the pedicle. This is a commonly underappreciated track of an epidural catheter. It is generally assumed that epidural catheters travel cephalad in the posterior epidural space. However, this image shows definitive evidence of the circuitous route often taken by an epidural catheter. Conventional teaching is to insert an epidural catheter 5 cm into the epidural space. Several studies contradict this and show that a low number of catheters are successfully advanced into the epidural space without coiling or deviating from their intended track.1Loose areolar tissue, fat, and blood vessels in the epidural space can contribute to deviations in final placement of the catheter tip. Lim et al. showed that approximately 65% of epidural catheter tips deviate laterally in the epidural space immediately after leaving the Tuohy needle tip. The catheter tip followed a straight direction in the posterior epidural space for more than 2 cm in only 35% of placements. Further, only 13% of catheter tips could be advanced ≥4 cm without coiling.1Choi et al. observed 17.6% of epidural catheters curling in the epidural space. They also reported that 63.5% of cephalad-directed thoracic epidural catheters (Touhy bevel up) were actually advanced as such, and 78% of caudally directed epidural catheters (Touhy bevel down) were advanced that direction.2A negative consequence of lateral epidural catheter tip deviation is misplacement into the paravertebral area via an intervertebral foramen. Misplacement into the anterior epidural space is one of the most common causes of unilateral epidural block.3The authors thank Jeanine P. Weiner-Kronish, M.D., Ph.D., Anesthetist-in-Chief and Professor of Anesthesia, and Paul Alfille, M.D., Ph.D., Assistant Professor of Anesthesia (both Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts), for their guidance and initial review of this manuscript.

Use of computational fluid dynamics to study the influence of the uncinate process on nasal airflow

Chronic rhinosinusitis is commonly treated by functional endoscopic sinus surgery involving excision of the uncinate process and opening of the osteomeatal complex. Computational fluid dynamics were used to compare nasal airflow after two different surgical interventions which involved opening the paranasal sinuses, excising the ethmoid sinus, and excising or preserving the uncinate process, in a cadaveric head model. Cross-sectional computed tomography images were obtained before and after the interventions. Imaging data were used to prepare computer simulations, which were used to assess the airflow characteristics of the nasal cavities and paranasal sinuses during inspiration and expiration, before and after intervention. Significantly larger nasal cavity airflow velocity changes were apparent following the uncinate process excising procedure. Nasal cavity airflow distribution remained relatively unchanged following the uncinate process preserving procedure. There was a significantly greater increase in airflow volume following the uncinate process excising procedure, compared with the uncinate process preserving procedure. Preservation of the uncinate process may significantly reduce the alteration of nasal cavity airflow dynamics occurring after functional endoscopic sinus surgery for chronic rhinosinusitis.

Three-Dimensional Modeling of Tracer Experiments To Determine Gas Trapping in Foam in Porous Media

Foam diversion is used worldwide in acid matrix-stimulation treatments and enhanced oil recovery. Gas trapping is a crucial component of foam mobility and diversion. Previous studies have estimated trapped-gas saturation from a fit of coreflood effluent profiles of one or more gas tracers to a one-dimensional (1D) model for tracer mass transfer. A major factor in these experiments is diffusion of the tracer between flowing and trapped gas. We previously reported X-ray computed tomography (CT) images of Xe tracer injected during steady-state foam flow, which for the first time allowed for direct visualization of the location of the tracer in the core throughout the experiment. Here, we extend the study by analyzing the diffusion of the tracer through trapped foam in 3D. Cross-sectional CT images show that in this experiment the tracer did not flow through the core evenly but mostly along the top and sides of the core. Within these regions, the tracer flowed in pathways separated by distances of a few millimeters. Modeling suggests that the tracer diffused through trapped gas between the flowing gas pathways quickly, while mass transfer between the larger region and foam in the rest of the core was significantly slower. A three-dimensional (3D) model of flow and diffusion of the tracer can fit the effluent data from the previous experiment quantitatively and fit CT images qualitatively. Moreover, the model fits the data well with values of the flowing-gas fraction that differ by a factor of 2 (0.25 and 0.51). We test four published methods of inferring the flowing-gas fraction against our synthetic data: the method of Friedmann et al. based on an early breakthrough of tracer, fitting effluent data with a 1D mass-transfer model using one or two tracers, and the method of Nguyen et al. (Nguyen, Q. P.; Currie, P. K.; Buijse, M.; Zitha, P. L. J. J. Pet. Sci. Eng. 2007, 58, 119−132) based on a break in a plot of the average tracer concentration in a given cross-section as a function of time. None of these methods were able to distinguish between the two cases with different flowing-gas fractions. Using the 1D model fitted to results for two tracers with different diffusion coefficients gave less accurate results than a fit using the slower diffusing tracer alone.

The Prevalence and Morphologic Classification of Distolingual Roots in the Mandibular Molars in a Korean Population

IntroductionThe aims of this study were to determine the incidence and concurrency rate of distolingual (DL) roots on mandibular molars and to classify them according to their morphologic features. MethodsSerial cross-sectional computed tomography images of the mandibles were collected retrospectively from 1,775 Korean patients of Mongoloid origin. The incidence of DL roots was calculated for each molar, and their patterns of concurrence were analyzed with the Fisher exact test. DL roots were categorized into five groups according to their morphologic characteristics using the three-dimensional reconstructed images. ResultsThe incidence rate of DL roots was highest for first molars (24.5%) and lowest for second molars (0.7%). They were often present concurrently in adjacent molars (p < 0.004). The morphologic characteristics of DL roots in the first molars varied greatly from a severely curved type (type III, 40.5%) to an underdeveloped small type or a conical type (2.5% and 1.4%, respectively). ConclusionData regarding the pattern of occurrence and the morphologic features of DL roots can provide useful information to clinicians, leading to higher rate of success of endodontic treatment.

The Prognostic Value of Residual FDG-Avidity Prior to Allogeneic Stem Cell Transplantation for Lymphoma.

Abstract 1200Poster Board I-222 Background:Chemosensitive disease, as determined by computed tomography (CT) or fluorine-18-deoxyglucose positron emission tomography (FDG-PET), is required for successful autologous hematopoietic stem cell transplant (autoHSCT) in patients with aggressive non-Hodgkin's lymphoma (NHL) and Hodgkin lymphoma (HL). However, whether chemosensitivity, as determined by FDG-PET, is a requirement for successful allogeneic hematopoietic stem cell transplantation (alloHSCT) has yet to be established. Therefore, we analyzed the survival of alloHSCT recipients transplanted at MSKCC between 2001-2007 for the treatment of relapsed or refractory NHL and HL who had both FDG-PET and CT imaging to assess response prior to alloHSCT. Our hypothesis is that FDG-PET prior to alloHSCT will add prognostic information compared to CT scan alone prior to alloHSCT. Methods:Thirty-seven lymphoma patients had combined pre-alloHSCT imaging (10 aggressive NHL, 12 indolent NHL, and 15 HL by WHO classification). Patients were scored as either complete remission (CR), partial remission (PR) or stable disease (SD) by CT according to previously published criteria (Cheson et al. JCO 1999). For the purposes of analysis, patients with PR or SD were classified together as non-CR. FDG-PET was scored as either positive, if FDG-avid disease was measurable on corresponding imaging (CT or magnetic resonance imaging), or FDG-negative prior to alloHSCT. Patients with progression of disease prior to alloHSCT by either FDG-PET and/or CT were excluded in view of their historically poor survival following alloHSCT. Results:The median age was 42 years (range 18-66) with 5 patients receiving myeloablative (MA) conditioning while the remainder received non-myeloablative (NMA) conditioning. Seventeen (46%) had received prior autologous transplants. Thirteen patients were transplanted with HLA-identical related donors (1 mismatched related donor) and the remaining 23 patients from unrelated donors (12 fully HLA-matched and 11 mismatched). Twenty-four (65%) of the patients were FDG-negative and 16 (43%) were in CR by CT prior to alloHSCT. Disparity between CT and FDG-PET response was observed in 8 FDG-PET negative patients (5 SD and 3 PR by CT). With a median follow-up for survivors of 38 months (range 9-92), the Kaplan-Meier estimates of overall (OS) and progression free survival (PFS) at 3 years post-alloHSCT were 64% and 56%, respectively. There was no significant difference in survival according to age < or ≥ 40 years, prior autoHSCT, conditioning intensity (MA or NMA) or WHO classification. FDG-negative patients had significant OS (Figure) and PFS improvement compared to FDG-positive patients (p=0.006 and p=0.02, respectively). Patients in CR had improved OS compared to those in PR/SD by CT imaging (p=0.02), however improvement in PFS was not significant (p=0.13). Patients that were FDG-PET negative and CT CR (n=16) had 88% OS at 3 years compared to 63% in the 8 patients that were FDG-PET negative and CT non-CR, although this difference was not significant (p=0.22). Conclusion:Response to therapy prior to alloHSCT as determined by FDG-PET offers critical prognostic information beyond traditional cross-sectional CT imaging considering the significant improvement in both OS and PFS. These data suggests that the goal of therapy prior to alloHSCT should be to normalize FDG-PET independent of tumor bulk. Prospective investigation is warranted to validate this conclusion. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Reconstruction of 3D images of internal log characteristics by means of successive 2D log computed tomography images

Abstract Although three-dimensional (3D) internal log images are useful to wood scientists for assessing internal log features, little work has been carried out on this subject. The aim of this paper was to demonstrate how two-dimensional (2D) log images may be combined to create 3D images of internal log features. The selected log features include heartwood, sapwood, bark, and knots in a sugar maple log and a black spruce log. The 2D cross-sectional images of the logs were acquired through computed tomography (CT) scanning. For each log, 72 successive 2D cross-sectional CT images of the log were employed to create the corresponding 3D internal log images based on the marching cubes algorithm. The results suggest that the proposed method can produce clear 3D images for each selected internal log features in sugar maple and black spruce. The accuracy analysis of the 3D reconstruction is still a huge challenge and should be fully investigated in future work.

Identification of selected internal wood characteristics in computed tomography images of black spruce: a comparison study

The feasibility of identifying internal wood characteristics in computed tomography (CT) images of black spruce was investigated using two promising classifiers: the maximum likelihood classifier (MLC) and the back propagation (BP) artificial neural network (ANN) classifier. Nine image features including one spectral feature (gray level values), a distance feature, and seven textural features were employed to develop the classifiers. The selected internal wood characteristics to be identified included heartwood, sapwood, bark, and knots. Twenty cross-sectional CT images of a black spruce log were randomly selected to develop the two classifiers. The results suggest that both classifiers produced high classification accuracy. Compared with the MLC classifier (80.9% overall accuracy), the BP ANN classifier had better classification performance (97.6% overall accuracy). Moreover, statistical analysis reveals that the heartwood of the black spruce log used in this study is the easiest to identify by either classifier compared with the other three log features. The results also suggest that the separability of one wood characteristic from the other wood characteristics in black spruce CT images is mainly related to moisture content.

Metastatic Deposit In The Skull

METASTATIC DEPOSIT IN THE SKULL © Kai-hung Fung, 2009 Artistically rendered 3D computed tomography (CT) An inside view of the skull bone near the vertex showing the spoke wheel pattern of bony destruction from metastatic deposit in the skull vault originating from carcinoma of thyroid in a 76 years old lady. The original cross-sectional CT image is shown in figure 2 below.