Ultrasonic computed tomography based on back scattering theory is the most powerful and accurate tool in ultrasound based imaging approaches because it is capable of providing quantitative information about the imaged target and detects very small targets. The duple-frequency distorted Born iterative method (DF–DBIM), which uses density information along with sound contrast for imaging, is a promising approach for imaging targets at the level of biological tissues. With two frequencies f₁ (low) and f₂ (high) through Nf₁ and Nf₂ iterations respectively, this method is used to estimate target density along with sound contrast. The implications of duple-frequency fusion for the image reconstruction quality of density information along with sound contrast based ultrasound tomography have been analyzed in this paper. In this paper, we concentrate on the selection of parameters that is supposed to be the best to improve the reconstruction quality of ultrasound tomography. When there are restraints imposed on simulated scenarios to have control of the computational cost, the iteration number Nf₁ is determined resulting in giving the best performance. The DF–DBIM is only effective if there are a moderate number of iterations, transmitters and receivers. In case that the number of transducers is either too large or too small, a result of reconstruction which is better than that of the single frequency approach is not produced by the implementation of DF–DBIM. A fixed sum N(iter) of Nf₁ and Nf₂ was given, the investigation of simulation results shows that the best value of Nf₁ is [N(iter)/2 − 1]. The error, when applying this way of choosing the parameters, will be normalized with the reduction of 56.11%, compared to use single frequency as used in the conventional DBIM method. The target density along with sound contrast is used to image targets in this paper. It is a fact that low-frequency offers fine convergence, and high-frequency offers fine spatial resolution. Wherefore, this technique can effectively expand DBIM's applicability to the problem of biological tissue reconstruction. Thanks to the usage of empirical data, this work will be further developed prior to its application in reality.
Image Processing, Computer-Assisted ; Methods ; Transducers ; Ultrasonics ; Ultrasonography

Background: Laparoscopic cholecystectomy is the first laparoscopic surgery that was performed at Cho Ray hospital in September 1992. In 2005, Quang Tri general hospital has performed successfully the first case of laparoscopic appendectomy. Objectives: To access the preliminary results of application on endoscopic surgery in Quang Tri general hospital. Subjects and method: A prospective study was conducted on 140 patients with laparoscopic surgery or retroperitoneal surgery, was performed in Quang Tri general hospital from September, 2005 to April, 2006. Results:Among 140 patients was operated, there was only one case of postoperative intestinal obstructive complication (accounted for 0.7%), no case of death. Operative aged was between 11 and 70 years old. The average surgical time was 65 minutes for cholecystectomy, 35 minutes for appendectomy, 85 minutes for ureterolithotomy, 80 minutes for gynecological diseases. 2 cases of cholecystectomy and appendectomy changed open surgery. Conclusion: Laparoscopic surgery is a safe and effective method. It can be developed in provincial hospitals. Quang Tri general hospital has successful preliminary developed the new technique.
Laparoscopy ;

Background: Situation of extremity injury caused by traffic accidents and occupational accidents are increasing in Vietnam. Therefore, the prevention and fight against these accidents are one of the key objectives to reduce the burden on the families of victims as well as for society. Objectives: To outline situation of extremity injury patients caused by traffic accident, treated in Viet Duc hospital from 2000-2004. Subjects and method: A retrospective study was conducted on 19.845 patients (14.562 males, 5.283 females, aged from 1-97 years old). The subjects were divided into 3 main groups: alone upper extremity injury, alone lower extremity injury and multiple fractures. Results: Extremity injury was common seen in people of working age (78.1%), men more than women (2.76/1 ratio), left foot more than right foot and it was common been in multiple fracture situation due to complex mechanisms of injury (50.3%), alone extremity injury (49.7%). The lower extremity injury was more common seen than upper extremity injury. Open fracture injury (27.3%), in which open fractures in lower extremity were more common seen. Open fractures in both 2 leg bones was the most common seen, accounted for 57.4% among total of open fractures. Amputation accounted for 8.3% among all case of open fractures and 2.3% among all case of extremity injuries. Conclusion: Extremity injury (lower extremity and upper extremity) caused by traffic accidents is common seen. The average, there are 3 emergency surgeries due to open fracture injury were performed daily in Viet Duc hospital per a total of about 11 traumatic emergency surgeries.
Fractures ; Bone ; Arm Injuries ; Leg Injuries ; Accidents ; Traffic ;

A study on 104 patients with chronic renal failure due to the obstructed urethral stone has shown that this disease in Vietnam was very severe, the nepthrotic creatinine clearance of 10ml/min occurred in 36 patients. The water, electrolyte and acid-base balance were severe. The recovering ability of morphism and rest function of patients with the chronic renal failure was high. A rest of patients that renal function can not be recovered mainly cause by large renal parenchymal lesions. The rest of nephron was very small that can not meet the function of endothelial balance. The patients should receive the kidney transplantation and periodical hemodialysis.
Kidney Failure, Chronic ; therapeutics

A 43 years old age patient with acute renal failure underwent a session of artificial kidney. Anaphylactic shock occurred after 1 hour. For treating, 30 mg of depercolon was injected and the condition was interrupted. To prevent this condition, author recommended the use of a relatively low volume of extern circulatory blood in beginning and the management this phenomenon in time by an antihistaminic medication.
Renal Dialysis ; Anaphylaxis ; Kidney Failure, Acute

The patients with hepatobiliary jaundice have an increased incidence of acute tubular necrosis. The hepatorenal syndrome represents a special category in the classification of the syndrome of acute liver and kidney failure. The treatment involved the use of prednisolone, exchange transfusion, hemodialysis, charcoal hemoperfusion, xenobiotic cross circulation and exvivo baboon liver perfusion
Liver Failure, Acute ; Kidney Failure ; Kidney Tubular Necrosis, Acute

Infertility is defined as the inability of a couple to conceive after having made attempts for 2 years. We conducted this study on 227 cases of male infertility. The results showed that 146 cases have oligospermia (the sperm count less than 20x106/mm3), 81 cases have asthenozoospermia. Our results in the treatment for asthenozoospermia with gonadotropine is very good, especially the therapy for Eumuch syndrome gets the best results
Infertility, Male ; Sperm Injections, Intracytoplasmic ; diagnosis ; therapeutics

Participants in this study were patients with acute renal failure who admitted ViÖt §øc Hospital. It is found that acute nonoliguric renal failure developed in 30% of the patients. It was diagnosed by blood creatinine level as 20 mg/L or 180 micromol/L and renal failure indices RFI  2 and FeNa2. Progress and prognosis of this condition were favorable. Most of patients responded with furosemide. Only a few patients need additional hemodialysis.
Kidney Failure, Acute ; Oliguria

The treatment of renal failure by the artificial kidney comprised hemodialysis, hemofiltration and CAPD. Hemodialysis is not without side effect such as hypotension, dysequilibrium syndrome. Hemodialysis is a treatment of choice in hemodynamic stable patients where fluid overload is not a major problem. When multiorgan failure. Such difficulties have been overcome by the introduction of specific modalities for the treatment of acute renal failure, named continuous artiovenous hemofiltration (CAVH) which have become nowadays a popular renal replacement therapy in the intensive care units.
Kidney Failure, Acute ; surgery ; therapeutics

A development trial and application of non-scalpel vasectomy on 3850 men more than 30 ages in the whole country during 1992-1993 has shown that it was a simple technique and easy to implement and train. The technical condition was very simple, only required a septic room and 3 basic medical equipments scissors and pincers. The complication of traditional technique and non-scalpel vasectomy was 3% and 0,63%, respectively. The revasectomy was simple, and can be implemented out of hospital.
Vasectomy ; Family Planning Services