MO784ABDOMINAL AORTIC CALCIFICATIONS AND ARTERIOVENOUS FISTULA CLINICAL OUTCOMES ON HAEMODIALYSIS PATIENTS

Background and Aims Vascular calcification has now been recognized as a major problem in dialysis patients because of its strong influence on the prognosis of this population. Several reports have shown the strong relationship between vascular calcification and clinical outcomes including cardiovascular events and arteriovenous fistula (AVF)survival. The aim of this study is to evaluate the severity of vascular calcifications in our hemodialysis patients and to determine its impact on the AVF survival. Method It is a transversal descriptive and analytical study including chronic haemodialysis patients in our unit of the nephrology department. A lateral lumbar spine radiograph was taken: the aortic arch calcification(ACC) score (VCS) was calculated according to the score validated by Kauppila and Schousboe. The overall VCS ranged from 0 to 24. Results Our study included 55 patients divided into 31 men and 24 women with a sex ratio of 1.29. The mean age was 49.54 ± 12.66 years. The mean duration in HD was 96.16± 73 months. 76.8% of the patients have hypertension, 26.8% are diabetic and 14.3% are smokers. AVF failure was noted in 34 patients (60.7%). We divided our population in 3 groups: G1:23 patients with a low VCS (41.1%), G2: 15 patients with a moderate VCS (26.8%) and G3: 17 patients with a severe VCS (30.4%). Patients in G2 and G3 were more frequently diabetics (p=0.05): over 50% of patients in G3 were diabetic and the mean duration in HD was longer: 133 months in G3, 102 months in G2 and 74 months in G1 with a significant difference p=0.03. We noted that AVF failure was more frequent in patients in G2 and G3 (65.7%) patients) versus patients in G1 (39.13%) with a significant difference (p=0.01) Conclusion vascular access dysfunction is one of the leading causes of morbidity and mortality in haemodialysis patients We have demonstrated throw this study the relation between the presence of higher AAC grade and the poor survival of AVF in our patients. So, an identification of these ACC by a simple lateral lumbar spine radiograph would allow the clinician to implement more rigorous and planned monitoring for such AVFs.

Intraoperative ultrasound visualization of paravertebral anatomy in the retroperitoneal space during lateral lumbar spine surgery

OBJECTIVELumbar surgery via a lateral approach is a minimally invasive and highly useful procedure. However, care must be taken to avoid its potentially fatal complications of intestinal and vascular injuries. The object of this study was to evaluate the usefulness of intraoperative ultrasound in improving the safety of lateral lumbar spine surgery.METHODSA transvaginal ultrasound probe was inserted into the operative field, and the intestinal tract, kidney, psoas muscle, and vertebral body were identified using B-mode ultrasound. The aorta, vena cava, common iliac vessels, and lumbar arteries and their associated branches were identified using the color Doppler mode.RESULTSThe study cohort comprised 100 patients who underwent lateral lumbar spine surgery, 92 via a left-sided approach. The intestinal tract and kidney lateral to the psoas muscle on the anatomical approach pathway were visualized in 36 and 26 patients, respectively. A detachment maneuver displaced the intestinal tract and kidneys in an anteroinferior direction, enabling confirmation of the absence of organ tissues above the psoas. In all patients, the major vessels anterior to the vertebral bodies and the lumbar arteries and associated branches in the psoas on the approach path were clearly visualized in the Doppler mode, and their orientation, location, and positional relationship with regard to the vertebral bodies, intervertebral discs, and psoas were determined.CONCLUSIONSWhen approaching the lateral side of the lumbar spine in the retroperitoneal space, intraoperative ultrasound allows real-time identification of the blood vessels surrounding the lumbar spine, intestinal tract, and kidney in the approach path and improves the safety of surgery without increasing invasiveness.

Effective Dose Reduction in Lateral Lumbar Spine Diagnostic Radiography Using X-Ray Tube Heel Effect

The study aimed to determine how the effective dose (ED) in lumbar spine X-ray examinations is influenced by patient positioning considering the X-ray tube heel effect. The study used Monte Carlo simulation of the effective dose. Using the heel effect, positioning of the patient in the head to anode direction reduces the effective dose by 5% when compared with the head to cathode positioning.