New approach for attenuation correction in SPECT images, using linear optimization

Photon attenuation as an inevitable physical phenomenon influences on the diagnostic information of SPECT images and results to errors in accuracy of quantitative measurements. This can be corrected via different physical or mathematical approaches. As the correction equation in mathematical approaches is nonlinear, in this study a new method of linearization called 'Piece Wise Linearization' [PWL] is introduced and to substantiate its validity for SPECT image reconstructions, a phantom study is performed. A SPECT scan of a homemade heart phantom filled with 2 mCi 99mTc was acquired by dual head Siemens E.Cam gamma camera equipped with LEHR collimator. Row data of the scan were transferred in DICOM format to a pc computer for reconstruction of the images using MLEM iterative algorithm in Matlab software. Attenuation map of the phantom micro [chi] were derived using PWL with linear optimization approach. Based on that, the attenuation corrected SPECT image of the phantom were reconstructed and compared with non-corrected image, using MLEM iterative algorithm. Comparison of the corrected and non-corrected images confirmed with CT attenuation correction method. Attenuation correction in SPECT image can be achieved successfully, using emission data and piecewise linearization with linear optimization approach. The corrected image of f[chi] and attenuation map micro[chi] of the heart phantom using this approach promise acceptable image quality for diagnostic clinical use

[Management of hemorrhagic syndrome]

Bleeding can occur when the vessels are affected by illness or injury. More rarely, a hemorrhagic syndrome can be the consequence of a hereditary or acquired anomaly of the haemostasis. A big number of hemorrhagic diseases are now identified. The notion of familial hemorrhagic disease, the circumstances of intervening of bleedings, as well as their localization, and the using of some drugs can help diagnosis. The diagnosis depends on the clinical analysis and the realization or exploring tests of haemostasis. This article aims at the recall of the different aetiological aspects a haemorhagic syndrome and to propose a pratical way for its management

Constitutional deficits in coagulation factors

Hereditary deficit of coagulation factors is rare affection. This is a retrospective study which analyse the coagulation parameters of 25 patients with an hereditary deficit. Deficiency on factor V, VII and VIII were the most frequent. Generally without symptoms, hereditary deficiency of coagulation factors must to be diagnosing with a great prudence for prevention of hemorrhagie riskin surgery

Approche epidemiologique des hemoglobinopathies au Maroc

The anomalies of hemoglobin are responsible in Morocco of many grave cases of hemolytic anemia. The study of hemoglobinopathic epidemiology can aid in a prevention based on the genetic counseling. The authors make an epidemiology approach of this disease using report on their experience and the publications. The result of this approach is that the Sickle Cell Disease is the most frequent hemoglobinopathy in the hospital milieu, and there are associations between: -Thalassemia and Hb S or C. - Hemoglobinose C and S or O. This result is discussed

Profile bilogique de la drepanocytose au Maroc [a propos de 85 cas]

The hemoglobinopathies are frequent in Morocco. The Sickle cell disease is one of the most important of these complaints. The authors report 85 cases of patients in the C.H.U. of Rabat, and expose the hematology characteristics of each form. The Sickle cell disease is a grave complaint with important and constant anemia which persists even out of hemolytic crises. The patients rarely attain adult age. The association of Sickle cell anemia and beta thalassemia has the same degree of gravity. Meanwhile the association of Sickle cell anemia and hemoglobin C disease is not so grave The Sickle cell trait, classically benign, can present a severe anemia

Electrophorese de l'hemoglobine sur acetate de cellulose: apports et limites

The research of an Abnormality of hemoglobin use simple and rapid techniques such as electrophoresis on cellulose acetate. Associated with family study and determination of A2 hemoglobin and F hemoglobin, allows, the diagnosis of thalassemia and Sickle cell disease. To be able to explore the other possible anomaly of hemoglobin, we have to use other techniques like electrophoresis on citrate agar [pH 6 - 6,2] or isoelectrofocusing