Information fusion for diagnosis coding support.

All patient-related medical information during a hospital stay in France, has to be collected and coded in the compilation of medical units discharge documents, according to a standardized approach. The process of describing a patient disease in terms of appropriate diagnostic codes is nevertheless, a non-intuitive operation for the physician. As a consequence, coding errors, inaccuracies and missing data are frequent, leading to potentially severe economical upshots. A coding support system developed to improve medical coding results, integrates three information processing methodologies, using the outputs from various Hospital Information System applications. Each methodology generates partial heterogeneous information, with considerable semantic variety. In order to properly synthesize these outputs, information fusion is required to produce enriched contextualized information, presented to the physician as an ordered list of suggested codes. This paper explores two information fusion approaches: voting system and possibilistic. Both methods are tested on a database of 1,000 discharge summaries, to show the interest of information fusion in this context. Results show that fusion methods perform better in most of the cases than partial information extraction methods.

Comparison of some reversible watermarking methods in application to medical images.

Several reversible watermarking schemes have been proposed for images of sensitive content, like medical imaging, for which any modification may affect their interpretation. In this work, we distinguish these methods according to the way watermark insertion is conducted: additive and substitutive. Some of these approaches have been tested on different sets of medical images issued from three distinct modalities: Magnetic Resonance Images, Positron Emission Tomography and Ultrasound Imaging. Comparison analysis has been conducted with respect to several aspects including data hiding capacity and image quality preservation. Experimental results show different limitations which depend on the watermark approach but also on image modality specificities.

Medical image integrity control seeking into the detail of the tampering.

In this paper, we propose a system which aims at verifying integrity of medical images. It not only detects and localizes alterations, but also seeks into the details of the image modification to understand what occurred. For that latter purpose, we developed an image signature which allows our system to approximate modifications by a simple model, a door function of similar dimensions. This signature is partly based on a linear combination of the DCT coefficients of pixel blocks. Protection data is attached to the image by watermarking. Whence, image integrity verification is conducted by comparing this embedded data to the recomputed one from the observed image. Experimental results with malicious image modification illustrate the overall performances of our system.

Mixed reversible and RONI watermarking for medical image reliability protection.

By attaching image authenticity and integrity proofs directly at the pixels level of an image, watermarking can help to raise up medical image protection. However, because of the induced distortions, specific schemes like lossless data hiding or watermarking Regions of Non Interest (RONI) have been proposed to guarantee the preservation of the image interpretation. In this article, we propose an image reliability protection mechanism which combines advantages of both lossless and RONI approaches in order to provide a better and continuous protection. The proposed system was applied to magnetic resonance images of the head. Experimental results illustrate the overall functionality of the system.

Clinical relevance of low levels of preformed alloantibodies detected by flow cytometry in the first year post-kidney transplantation.

OBJECTIVE: To determine the prevalence of transplants performed with a false-negative cytotoxicity cross-match and to analyze the clinical relevance of alloantibodies (Ab) detected only by flow cytometry (flow). METHODS: We studied 66 patients undergoing kidney transplantation from a cadaveric donor. All patients had a simultaneous negative T+AHG+DTT and B+DTT. Pretransplant sera were retrospectively analyzed by flow cytometry according to an Emory University protocol: (1) T+ and B-: Ab anti-class I; (2) T- and B+: anti-class II; (3) T+B+: anti-class I + II. Chi-square, Fisher exact, Student t test, and Kaplan Meier analyses were employed with significance assigned at P < or = .05. RESULTS: The overall incidence of false-negative cytotoxicity was 33.3% (22/66), namely, 6.1% (n = 4) anti-class I; 9.1% (n = 6) anti-class II; and 18.2% (n = 12) anti-class I + II. Primary nonfunctioning grafts occurred in 6.8% (3/44) and 13.6% (3/22) negative and positive flow patients (two anti-class I + II and one class II; P = .39). The incidence of graft loss in the first year was respectively, 13.6% (6/44) and 18.2% (4/22; two anti-class II and two anti-class I + II; P = .72). Compared to flow-negative grafts, creatinine levels were significantly higher among flow-positive patients at 8 and 12 weeks. One-year graft survivals were 86.4% among negative versus 81.8% for the positive group (P = .67). CONCLUSIONS: We observed that 33% of kidney transplant recipients had low levels of alloantibodies detected only by flow. This single factor was associated with the worst graft function in the first trimester with a suggestion of a higher risk for non-functioning graft.

Immunoglobulin G-positive in B-cell cross-match decreases kidney allograft survival.

We retrospectively studied all 1149 transplants performed at our center between 1993 and 2003 to determine the incidence and clinical effect of pretransplant B-positive cross-match on kidney graft survival. The patients were divided in two groups: B-negative (n = 1102) and B-positive in current sera (n = 47; 4.1%). AB-positive test was more frequent among regrafted patients (14% vs 3%; P = .00). Demographic data were not different between the groups. The overall rate of graft loss was similar (26% vs 24%, respectively; P = .86). However, early nonsurgical graft losses were more frequent among B-positive patients (46% vs 20%, respectively; P = .04). IgM was the most frequent immunoglobulin in the B-positive group (76% IgM and 24% IgG). There was no significant difference between B-negative and B-positive groups in the 1-, 5-, and 10-year graft survival rates (87% vs 83%, 73% vs 78%, 64% vs 66%, respectively; P = .87). The graft survival was significantly reduced comparing an IgG anti-B cell to the B-negative group (P = .03) as well as IgG compared to IgM (P = .004). In conclusion, only B-positive cross-match due to IgG decreased graft survival. Even though it is an uncommon situation (0.9%), this study stressed the clinical value of the B-cell cross-match as a tool to identify patients with a higher immunological risk.

Synthesis of a functional information with anatomical landmarks by multiresolution fusion of brain images.

In order to help clinicians with the diagnosis of neurodegenerative diseases, we provide a synthetic functional information located in relation with anatomical structures. The final image is processed by multimodal data fusion between SPECT and MR images. We propose a new method for the management of such multiresolution data, in which a geometrical model allows an accurate correspondence of voxels from both images, while preserving at best both original pieces of information. We use this matching method to replace the interpolation step in the compulsory image registration of the data fusion process. The geometrical model is first built from registration parameters. Computational geometry algorithms, applied to this model, allow the computation of numerical values used to process the final information. The method has been applied to brain perfusion and neurotransmission SPECT images.

The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann) (Dipteria: Tephritidae)

Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC) activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area), and the number of spermatozoa of Anastrepha fraterculus (Wiedemann) were analyzed at alternating (20º/6ºC and 20º/13°C) and constant (6°C; 25°C) temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins

The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae).

Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC) activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area), and the number of spermatozoa of Anastrepha fraterculus (Wiedemann) were analyzed at alternating (20 degrees/6 degrees C and 20 degrees/13 degrees C) and constant (6 degrees C; 25 degrees C) temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins.

The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann) (Dipteria: Tephritidae)

Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC) activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area), and the number of spermatozoa of Anastrepha fraterculus (Wiedemann) were analyzed at alternating (20º/6ºC and 20º/13°C) and constant (6°C; 25°C) temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins.

O desenvolvimento ovariano, ovoposição, eclosão larval, atividade de ornitina descarboxilase (ODC), medidas de largura, comprimento e área do ovário, testículo e apódema ejaculatório e número de espermatozóides de Anastrepha fraterculus (Wiedemann) foram analisados em temperaturas alternadas (20º/6°C e 20º/13°C) e constantes (6°C e 25°C). A longevidade e a expectativa de vida também foram analisadas em ambos os sexos. Todos os resultados sugerem que a temperatura baixa e principalmente as temperaturas alternadas afetam não somente o potencial reprodutivo de machos e fêmeas, mas também sua longevidade e expectativa de vida, prolongando-as. Essas mudanças podem ser uma poderosa estratégia usada por A. fraterculus para sobreviver às condições estressantes de temperatura observadas no inverno na região produtora de maçãs, tornando-as capazes de aumentar sua densidade populacional e causar dano à maçã no início da primavera.