Prospective study of the additional benefit of plexus magnetic resonance imaging in the diagnosis of chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: Hypertrophy/signal hyperintensity and/or gadolinium enhancement of plexus structures on magnetic resonance imaging (MRI) are observed in two-thirds of cases of typical chronic inflammatory demyelinating polyneuropathy (CIDP). The objective of our study was to determine the additional benefit of plexus MRI in patients referred to tertiary centers with baseline clinical and electrophysiological characteristics suggestive of typical or atypical CIDP. METHODS: A total of 28 consecutive patients with initial suspicion of CIDP were recruited in nine centers and followed for 2 years. Plexus MRI data from the initial assessment were reviewed centrally. Physicians blinded to the plexus MRI findings established the final diagnosis (CIDP or neuropathy of another cause). The proportion of patients with abnormal MRI was analyzed in each group. RESULTS: Chronic inflammatory demyelinating polyneuropathy was confirmed in 14 patients (50%), as were sensorimotor CIDP (n = 6), chronic immune sensory polyradiculoneuropathy (n = 2), motor CIDP (n = 1) and multifocal acquired demyelinating sensory and motor neuropathy (n = 5). A total of 37 plexus MRIs were performed (17 brachial, 19 lumbosacral and 8 in both localizations). MRI was abnormal in 5/37 patients (14%), all of whom were subsequently diagnosed with CIDP [5/14(36%)], after an atypical baseline presentation. With plexus MRI results masked, non-invasive procedures confirmed the diagnosis of CIDP in all but one patient [1/14 (7%)]. Knowledge of the abnormal MRI findings in the latter could have prevented nerve biopsy being performed. CONCLUSION: Systematic plexus MRI in patients with initially suspected CIDP provides little additional benefit in confirming the diagnosis of CIDP.

Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics.

OBJECTIVE: To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO). MATERIALS AND METHODS: Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Sloperise) and CT variables were the bone and segment involved (OObone and OOsegment, respectively), OO location relative to the native cortex (OOcortex), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmaxvessel). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed. RESULTS: DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Sloperise of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmaxvessel of 1.10 ± 0.60 mm. By univariate analysis, Sloperise correlated significantly with pain duration and Dmaxvessel (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Sloperise correlated significantly with OObone (P < 0.001), with a steeper slope for OOs located in short or flat bones. CONCLUSION: This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones.

QCT of the proximal femur--which parameters should be measured to discriminate hip fracture?

SUMMARY: For quantitative computed tomography (QCT), most relevant variables to discriminate hip fractures were determined. A multivariate analysis showed that trabecular bone mineral density (BMD) of the trochanter with "cortical" thickness of the neck provided better fracture discrimination than total hip integral BMD. A slice-by-slice analysis of the neck or the inclusion of strength-based parameters did not improve fracture discrimination. INTRODUCTION: For QCT of the proximal femur, a large variety of analysis parameters describing bone mineral density, geometry, or strength has been considered. However, in each given study, generally just a small subset was used. The aim of this study was to start with a comprehensive set and then select a best subset of QCT parameters for discrimination of subjects with and without acute osteoporotic hip fractures. METHODS: The analysis was performed using the population of the European Femur Fracture (EFFECT) study (Bousson et al. J Bone Min Res: Off J Am Soc Bone Min Res 26:881-893, 2011). Fifty-six female control subjects (age 73.2 ± 9.3 years) were compared with 46 female patients (age 80.9 ± 11.1 years) with acute hip fractures. The QCT analysis software MIAF-Femur was used to virtually dissect the proximal femur and analyze more than 1000 parameters, predominantly in the femoral neck. A multivariate best-subset analysis was used to extract the parameters best discriminating hip fractures. All results were adjusted for age, height, and weight differences between the two groups. RESULTS: For the discrimination of all proximal hip fractures as well as for cervical fractures alone, the measurement of neck parameters suffices (area under the curve (AUC) = 0.84). Parameters characterizing bone strength are discriminators of hip fractures; however, in multivariate models, only "cortical" cross-sectional area in the neck center remained as a significant contributor. The combination of one BMD parameter, trabecular BMD of the trochanter, and one geometry parameter, "cortical" thickness of the neck discriminated hip fracture with an AUC value of 0.83 which was significantly better than 0.77 for total femur BMD alone. A comprehensive slice-based analysis of the neck along its axis did not significantly improve hip fracture discrimination. CONCLUSIONS: If QCT of the hip is performed, the analysis should include neck and trochanter. In particular, for fractures of any type, a comprehensive slice-based analysis of the neck along its axis did not significantly improve hip fracture discrimination nor did the inclusion of strength-related parameters other than "cortical" area or thickness. One BMD and one geometry parameter, in this study, the combination of trabecular BMD of the trochanter and of "cortical" thickness of the neck resulted in significant hip fracture discrimination.

Muscle MRI STIR signal intensity and atrophy are correlated to focal lower limb neuropathy severity.

OBJECTIVES: The objective is to determine if muscle MRI is useful for assessing neuropathy severity. METHODS: Clinical, MRI and electromyography (EMG) examinations were performed in 17 patients with focal lower limb neuropathies. MRI Short Tau Inversion Recovery (STIR) signal intensity, amyotrophy, and muscle fatty infiltration measured after T1-weighted image acquisition, EMG spontaneous activity (SA), and maximal voluntary contraction (MVC) were graded using semiquantitative scores and quantitative scores for STIR signal intensity and were correlated to the Medical Research Council (MRC) score for testing muscle strength. Within this population, subgroups were selected according to severity (mild versus severe), duration (subacute versus chronic), and topography (distal versus proximal) of the neuropathy. RESULTS: EMG SA and MVC MRI amyotrophy and quantitative scoring of muscle STIR intensity were correlated with the MRC score. Moreover, MRI amyotrophy was significantly increased in severe, chronic, and proximal neuropathies along with fatty infiltration in chronic lesions. CONCLUSIONS: Muscle MRI atrophy and quantitative evaluation of signal intensity were correlated to MRC score in our study. Semiquantitative evaluation of muscle STIR signal was sensitive enough for detection of topography of the nerve lesion but was not suitable to assess severity. Muscle MRI could support EMG in chronic and proximal neuropathy, which showed poor sensitivity in these patients.

Bone marrow lesions identified by MRI in knee osteoarthritis are associated with locally increased bone mineral density measured by QCT.

OBJECTIVE: Bone marrow lesions (BMLs) in the knee are associated with pain and compartment-specific joint space narrowing. However, the correlation of BMLs with bone mineral density (BMD) has rarely been investigated. The aim of the present study was to examine whether BMD in BMLs is altered compared to the surrounding bone. DESIGN: Thirty-four BMLs detected in osteoarthritis (OA) knees (KL grade 2 and 3) of 26 patients were investigated. A 3D-segmentation was used to determine BML volumes of interest (VOI) and their surrounding bone in MR images. These VOIs were registered to corresponding single-energy QCT images and a BMD analysis was performed. The same VOIs were transferred to control datasets (19 OA patients without BMLs) by an elastic registration, where the BMD analysis was repeated. To account for the dependence of bone marrow composition on BMD measures derived using single-energy QCT, simulations were performed to evaluate how changing fat-water compositions likely occurring with BML development may influence BMD measures and observed BMD differences between patients with and without BMLs. The association between loading in the knee and the occurrence of BMLs was investigated by medial to lateral (M:L) BMD ratios. RESULTS: BMD was significantly increased at BML locations, even with a fat-to-water conversion rate of 39%. The M:L BMD ratio was significantly increased in bones with medial BMLs. CONCLUSIONS: BMD was examined exactly at BML locations and surrounding bone using highly accurate segmentation and registration methods. BMD was significantly increased at BML locations (P < 0.05).

CT imaging for the investigation of subchondral bone in knee osteoarthritis.

In osteoarthritis, magnetic resonance imaging is the method of choice to image articular cartilage and "bone marrow lesions." However, the calcified cartilage, the subchondral bone plate, and trabecular subchondral bone that are mineralized tissues strongly attenuate X-rays and are therefore potentially accessible for analyses using computed tomography (CT). CT images nicely show osseous cardinal signs of advanced osteoarthritis such as osteophytes, subchondral cysts, and subchondral bone sclerosis. But more importantly, CT can help us to better understand the pathophysiology of knee osteoarthritis from the measurement of the density and structure of subchondral mineralized tissues in vivo. For that purpose, we recently developed dedicated image analysis software called Medical Image Analysis Framework (MIAF)-Knee. In this manuscript, our aims are to present current knowledge on CT imaging of the subchondral bone in knee osteoarthritis and to provide a brief introduction to basic technical aspects of MIAF-Knee as well as preliminary results we obtained in patients with knee osteoarthritis as compared to control subjects.

Trabecular bone score (TBS): available knowledge, clinical relevance, and future prospects.

The diagnosis of osteoporosis rests on areal bone mineral density (BMD) measurement using DXA. Cancellous bone microarchitecture is a key determinant of bone strength but cannot be measured using DXA. To meet the need for a clinical tool capable of assessing bone microarchitecture, the TBS was developed. The TBS is a texture parameter that evaluates pixel gray-level variations in DXA images of the lumbar spine. The TBS variations may reflect bone microarchitecture. We explain the general principles used to compute the TBS, and we report the correlations between TBS and microarchitectural parameters. Several limitations of the TBS as it is used now are pointed out. We discuss data from currently available clinical studies on the ability of the TBS to identify patients with fractures and to evaluate the fracture risk. We conclude that this new index emphasizes the failure of the BMD T-score to fully capture the fragility fracture risk. However, although microarchitecture may influence the TBS, today, to the best of our understanding, there is no sufficient evidence that a TBS measurement provides reliable information on the status of the bone microarchitecture for a given patient. The TBS depends on gray-level variations and in a projectional image obtained in vivo, these variations can have many causes. Nevertheless, as clinical studies suggest that the TBS predicts the risk of fracture even after adjustment for BMD, we are encouraged to learn more about this score. Additional studies will have to be performed to assess the advantages and limitations of the TBS, in order to ensure that it is used appropriately in clinical practice.

How is quality of life after total hip replacement related to the reconstructed anatomy? A study with low-dose stereoradiography.

PURPOSE: The purpose of this study was to evaluate the relationships between the three-dimensional anatomy of operated hip in standing position using low-dose stereo-radiography imaging system and postoperative hip disability and osteoarthritis outcome score (HOOS) after total hip arthroplasty (THA). MATERIAL AND METHODS: A total of 123 patients who underwent THA during a one-year period were included. There were 50 men and 73 women with a mean age of 67.3±13.6 (SD) years (range: 19-89 years). All patients underwent pre- and postoperative low-dose stereo-radiography examination and completed a HOOS form (score from 0 to 100, 100 for full satisfaction). We recorded 16 anatomical parameters before THA, and 15 after THA. After binary transformation of HOOS score using 70 as threshold value, outcome was assessed using logistic or generalised linear models. RESULTS: A total of 103 patients (103/123; 83.7%) had a HOOS score≥70 and were considered as the satisfied group. A significant difference in pelvic incidence (the angle between a line perpendicular to the sacral plate at its midpoint and a line connecting the same point to the centre of the bicoxofemoral axis) was found between the satisfied 56.4±10.4 (SD)° (range: 31-85°) and the unsatisfied group 48.7±8.9 (SD)° (range: 40-65) (P=0.006). The relative variation of offset (distance from the centre of rotation of the femoral head to a line bisecting the long axis of the femur) compared to the contralateral hip was -7% in the satisfied group and 7.2% in the unsatisfied group (P=0.01). CONCLUSION: Pelvic incidence, a parameter independent of the reconstructed anatomy, probably influences the quality of life of patients with THA, via pelvic compensatory capabilities. A loss of femoral offset negatively influences the satisfaction of patients.

Dactylitis: A pictorial review of key symptoms.

Dactylitis refers to a global swelling of a finger or a toe giving it a clinical sausage-shape presentation. It is an extremely suggestive symptom as it guides the rheumatologist towards a shortlist of diagnoses. However, radiologists are less familiar with dactylitis. The aim of this review is to detail and illustrate the main causes of dactylitis using standard X-ray imaging, ultrasound, computed tomography and magnetic resonance imaging in order to make radiologists more familiar with this symptom by illustrating the various conditions that are associated with dactylitis including infection, peripheral spondyloarthritis, sarcoidosis, microcrystalline deposition, osteoid osteoma, and sickle cell disease.

Comparison of MR-arthrography and CT-arthrography in hyaline cartilage-thickness measurement in radiographically normal cadaver hips with anatomy as gold standard.

OBJECTIVE: To compare magnetic resonance (MR)-arthrography and multidetector-spiral-computed-tomography (MDSCT)-arthrography in cartilage-thickness measurement, in hips without cartilage loss, with coronal anatomic slices as gold standard. METHOD: Institutional review board permission to study cadavers of individuals who willed their bodies to science was obtained. Two independent observers measured femoral and acetabular cartilage thicknesses of 12 radiographically normal hips (six women, five men; age range, 52-98 years; mean age, 76.5 years), on MDSCT-arthrographic and MR-arthrographic reformations, and on coronal anatomic slices, excluding regions of cartilage loss. Inter- and intraobserver reproducibilities were determined. Analysis of variance (ANOVA) was used to test differences between MR-arthrographic and MDSCT-arthrographic measurement errors compared to anatomy. RESULTS: By MR-arthrography, cartilage was not measurable at approximately 50% of points on sagittal and transverse sections, compared to 0-6% of the points by MDSCT-arthrography. In the coronal plane, the difference between MDSCT-arthrographic and MR-arthrographic measurement errors was not significant (P=0.93). CONCLUSION: In the coronal plane, MR-arthrography and MDSCT-arthrography were similarly accurate for measuring hip cartilage thickness.

Relationships of trabecular bone structure with quantitative ultrasound parameters: in vitro study on human proximal femur using transmission and backscatter measurements.

The present study was designed to assess the relationships between QUS parameters and bone density or microarchitecture on samples of human femoral trabecular bone. The normalized slope of the frequency-dependent attenuation (nBUA), the speed of sound (SOS) and the broadband ultrasound backscatter coefficient (BUB) were measured on 37 specimens of pure trabecular bones removed from upper parts of fresh human femurs. Bone mineral density (BMD) was assessed using a clinical scanner. Finally, 8 mm diameter cylindrical cores were extracted from the specimens and their microarchitecture was reconstructed after synchrotron radiation microtomography experiments (isotropic resolution of 10 microm). A large number of microarchitectural parameters were computed, describing morphology, connectivity and geometry of the specimens. BMD correlated with all the microarchitectural parameters and the number of significant correlations was found among the architectural parameters themselves. All QUS parameters were significantly correlated to BMD (R=0.83 for nBUA, R=0.81 for SOS and R=0.69 for BUB) and to microarchitectural parameters (R=-0.79 between nBUA and Tb.Sp, R=-0.81 between SOS and Tb.Sp, R=-0.65 between BUB and BS/BV). Using multivariate model, it was found that microstructural parameters adds 10%, 19%, and 4% to the respective BMD alone contribution for the three variables BUA, SOS and BUB. Moreover, the RMSE was reduced by up to 50% for SOS, by up to 21% for nBUA and up to 11% when adding structural variables to BMD in explaining QUS results. Given the sample, which is not osteoporosis-enriched, the added contribution is quite substantial. The variability of SOS was indeed completely explained by a multivariate model including BMD and independent structural parameters (R(2)=0.94). The inverse problem on the data presented here has been addressed using simple and multiple linear regressions. It was shown that the predictions (in terms of R(2) or RMSE) of microarchitectural parameters was not enhanced when combining 2 or 3 QUS in multiple linear regressions compared to the prediction obtained with one QUS parameter alone. The best model was found for the prediction of Tb.Th() from BUA (R(2)=0.58, RMSE=17 microm). Given the high values of RMSE, these linear models appear of limited clinical value, suggesting that appropriate models have to be derived in order to solve the inverse problem. In this regard, a very interesting multivariate model was found for nBUA and BUB with Tb.Th and Tb.N, in agreement with single scattering theories by random medium. However, the source of residual variability of nBUA and BUB (15% and 45% respectively) remained unexplained.

Prediction of bone mechanical properties using QUS and pQCT: study of the human distal radius.

The objective was to compare the prediction of bone mechanical properties provided by axial transmission to that provided by peripheral quantitative computed tomography (pQCT) at the distal radius. The distal radius is the location for Colles' fractures, a common osteoporosis related trauma situation. Measurements of the radial speed of sound were performed using three axial transmission devices: a commercial device (Sunlight Omnisense, 1.25 MHz), a bi-directional axial transmission prototype (1 MHz), both measuring the velocity of the first arriving signal (FAS), and a low frequency (200 kHz) device, measuring the velocity of a slower wave. Co-localized pQCT measurements of bone mineral density and cortical thickness were performed. Ultrasound and pQCT parameters were compared to mechanical parameters such as failure load and Young's modulus, obtained using quasistatic compressive mechanical testing and finite elements modelling (FEM). Correlations of the ultrasound and pQCT parameters to mechanical parameters were comparable. The best predictor of failure load was the pQCT measured cortical thickness. The best predictor of Young's modulus was the bi-directional SOS. The low frequency device significantly correlated to cortical thickness and failure load. The results suggest that different axial transmission approaches give access to different bone mechanical parameters. The association of different axial transmission techniques should be able to provide a good prediction of bone mechanical parameters, and should therefore be helpful for fracture risk prediction.

Prediction of mechanical properties of cortical bone by quantitative computed tomography.

The relevance of Finite-Element models for hip fracture prediction should be increased by the recent subject-specific methods based on computed tomography (CT-scan), regarding the geometry as well as the material properties. The present study focused on the prediction of subject-specific mechanical parameters of cortical bone (Young's modulus and ultimate strength) from the bone density measured by CT. A total of 46 compression and 46 tension samples from 13 donors (mean age+/-S.D.: 81.8+/-12.7 years) were harvested in the femoral mid-diaphysis and tested until failure. The Young's modulus and ultimate strength were linearly correlated with the bone density measured by CT, for tension as well as compression (0.43

An anatomical subject-specific FE-model for hip fracture load prediction.

In order to reduce the socio-economic burden induced by osteoporotic hip fractures, finite element models have been evaluated as an additional diagnostic tool for fracture prediction. For a future clinical application, the challenge is to reach the best compromise between model relevance and computing time. Based on this consideration, the current study focused on the development and validation of a subject-specific FE-model using an original parameterised generic model and a specific personalization method. A total of 39 human femurs were tested to failure under a quasi-static compression in stance configuration. The corresponding FE- models were generated and for each specimen the numerical fracture load (FFEM) was compared with the experimental value (FEXP), resulting in a significant correlation (FEXP = 1.006 FFEM with r2 = 0.87 and SEE = 1220 N, p < 0.05) obtained with a reasonable computing time (30 mn). Further in vivo study should confirm the ability of this FE-model to improve the fracture risk prediction.

[Soft tissue tumors and pseudotumors of the foot and ankle]. / Tumeurs et pseudo-tumeurs des tissus mous de la région pied-cheville.

Soft tissue masses around the foot and ankle are frequent. While benign lesions are two times more frequent than malignant lesions, the latter still represent one third of all lesions. The main purpose of this article is to propose a systematic approach to the differential diagnosis of soft tissue tumors of the foot and ankle based on a combination of 5 elements: clinical history and physical examination, top 10 most frequent diagnoses, patient age, lesion location, and MRI features of the mass. Selected soft tissue tumors will be described and illustrated with emphasis on these 5 elements.

De novo reconstruction of functional bone by tissue engineering in the metatarsal sheep model.

Large bone defects are still a challenge to orthopedic surgeons. In this study, a massive bone defect with a clinically relevant volume was efficiently reconstructed by transplanting an engineered bone in which mesenchymal stem cells (MSCs) expanded in autologous serum (AS) were combined with a porous scaffold. In the first step, we established that the way in which the MSCs are distributed over the scaffold affects the ultimate bone-forming ability of the transplant: constructs consisting of a natural coral scaffold and a pseudo-periosteal layer of MSCs surrounding the implant (coral-MSC3D) formed significantly more bone than constructs in which the MSCs were distributed throughout the implant (p = 0.01). However, bone healing occurred in only one sheep, owing to the high resorption rate of natural coral scaffold. To overcome this problem, constructs in which MSCs were combined with a porous coralline-based hydroxyapatite (CHA) scaffold having the same architecture as natural coral but a lower resorption rate were prepared. After their implantation, these constructs were found to have the same osteogenic potential as autologous bone grafts in terms of the amount of newly formed bone present at 4 months (p = 0.89) and to have been completely replaced by newly formed, structurally competent bone within 14 months. Nevertheless, although the rate of bone healing was strikingly improved when CHA-MSC3D constructs were used (five of seven animals healed) as compared with the coral-MSC3D construct (one of seven healed), it was still less satisfactory than that obtained with autografts (five of five healed).

Links between mechanical behavior of cancellous bone and its microstructural properties under dynamic loading.

Previous studies show that in vivo assessment of fracture risk can be achieved by identifying the relationships between microarchitecture description from clinical imaging and mechanical properties. This study demonstrates that results obtained at low strain rates can be extrapolated to loadings with an order of magnitude similar to trauma such as car crashes. Cancellous bovine bone specimens were compressed under dynamic loadings (with and without confinement) and the mechanical response properties were identified, such as Young׳s modulus, ultimate stress, ultimate strain, and ultimate strain energy. Specimens were previously scanned with pQCT, and architectural and structural microstructure properties were identified, such as parameters of geometry, topology, connectivity and anisotropy. The usefulness of micro-architecture description studied was in agreement with statistics laws. Finally, the differences between dynamic confined and non-confined tests were assessed by the bone marrow influence and the cancellous bone response to different boundary conditions. Results indicate that architectural parameters, such as the bone volume fraction (BV/TV), are as strong determinants of mechanical response parameters as ultimate stress at high strain rates (p-value<0.001). This study reveals that cancellous bone response at high strain rates, under different boundary conditions, can be predicted from the architectural parameters, and that these relations with mechanical properties can be used to make fracture risk prediction at a determined magnitude.

Distribution of intracortical porosity in human midfemoral cortex by age and gender.

The purpose of this study was to describe the age-specific distribution of midfemoral intracortical porosity throughout the cortical width in males and females. Microradiography and an automated image analysis system were used to study midfemoral cortical bone specimens from 163 white people, including 77 males and 86 females, in a recent anthropological collection covering a broad age range. In each specimen, porosity (percentage of the cortical bone area occupied by pores), pore number, and pore size were measured throughout the entire cortex and in three cortical subregions of equal width labeled the periosteal, midcortical, and endosteal subregions. For each gender, relationships linking age to porosity, pore number, and mean pore size were assessed using regression analysis. In addition, age- and site-related changes in these three variables were tested for significance using two-way analysis of variance (ANOVA). Age explained 52% of the porosity variance in females and 13.5% in males. In each gender, there were significant age- and site-related differences in porosity, pore number, and pore size. In adults aged 60 years or younger, both pore size and pore number increased with increasing age, whereas in adults older than 60 years, pore size continued to increase but pore number decreased. In males, the age-related changes in pore size and pore number were proportionally similar in the three cortical subregions. In females, in contrast, the changes predominated in the endosteal subregion and resulted in significant cortical thinning.

CACNA1A gene de novo mutation causing hemiplegic migraine, coma, and cerebellar atrophy.

Familial hemiplegic migraine is caused by CACNA1A missense mutations in 50% of families, including all families with cerebellar ataxia. A patient with healthy parents, who experienced prolonged attacks of migraine with hemiplegia, coma, and seizures, is reported. The patient also had mental retardation, permanent cerebellar ataxia with cerebellar atrophy, and right-sided brain atrophy. This patient carried a de novo Tyr 1385 Cys mutation in the CACNA1A gene and illustrates a novel phenotype associated with CACNA1A mutations.

Assessment of malignancy in pulmonary lesions: FDG dual-head coincidence gamma camera imaging in association with serum tumor marker measurement.

UNLABELLED: The purpose of the study was to evaluate the performance of dual-head coincidence gamma camera imaging using FDG in association with serum marker assays in identifying lung carcinoma in patients with abnormal findings on chest radiography. METHODS: A prospective evaluation of FDG imaging with coincidence detection emission tomography (CDET) using a dual-head gamma camera combined with the assessment of 3 sensitive serum markers of lung cancer (carcinoembryonic antigen, neuron specific enolase, and CYFRA 21-1) was performed on the same day on 58 consecutive patients with known or suspected lung malignancy. RESULTS: Fifty-three patients were proven to have lung cancer, and 5 patients had benign lung disease. Coincidence imaging showed significantly increased FDG uptake in 49 of 53 patients with proven malignancy (sensitivity, 92.5%) and in 3 patients with benign disease. FDG imaging had negative findings in 4 patients with proven malignancy and 2 patients with benign disease. Serum tumor marker levels were elevated in 42 of 53 cancer patients (sensitivity, 79.2%) and normal in 11 patients with proven malignancy. Nine patients with proven malignancy had positive findings on FDG images and negative marker assays. Two patients with proven malignancy had negative findings on FDG images and positive marker assays. The positive predictive value for lung cancer was 94.2% for FDG alone and 97.6% for FDG in association with serum markers. CONCLUSION: In this study, FDG CDET imaging was a powerful tool for evaluating patients with lung lesions suggestive of malignancy. Although the determination of serum marker levels was less accurate than FDG imaging, positive FDG results found in association with positive markers significantly increased the likelihood of lung malignancy.