Biomedical subjects

Alexandros Hadjipavlou

Publications and source records attributed to Alexandros Hadjipavlou.

4 recordsLinked to original sources

PubMed2004

Patient exposure and associated radiation risks from fluoroscopically guided vertebroplasty or kyphoplasty.

PURPOSE: To derive normalized data for the estimation of effective, gonadal, and peak skin doses to patients undergoing vertebroplasty or kyphoplasty and to investigate the potential for cancer induction, genetic effects, and radiation-induced skin injury after such procedures. MATERIALS AND METHODS: Dose values normalized over dose-area product were determined for all radiosensitive organs and tissues by using a humanoid phantom and thermoluminescence dosimetry separately for anteroposterior and lateral projections. Measurements were obtained for treatments of the fifth, eighth, and 11th thoracic vertebrae and the first, third, and fifth lumbar vertebrae. Total fluoroscopy time and resultant dose-area product from each fluoroscopic exposure were monitored in 11 consecutive patients (seven women and four men) undergoing kyphoplasty. The age range of these patients was 41-78 years, and the mean age was 58 years. RESULTS: Mean total fluoroscopy time for kyphoplasty was 10.1 minutes +/- 2.2 (standard deviation). Mean effective dose to patients from kyphoplasty was 8.5-12.7 mSv, and mean gonadal dose was 0.04-16.4 mGy, depending on the level of the treated vertebra. Skin injuries after kyphoplasty are improbable if source-to-skin distance is 35 cm or more; however, such injuries may occur if the total fluoroscopy time per projection is extended and/or the source-to-skin distance is less than 35 cm during the procedure. CONCLUSION: Patient radiation exposure and associated risks from vertebroplasty or kyphoplasty may be considerable. Data obtained in the current study may be used to establish patient effective dose, gonadal dose, and entrance skin exposure, as well as associated risks, from these fluoroscopically guided surgical treatments of spinal disorders.

Adult↗

PubMed2004

Estimation of patient dose and associated radiogenic risks from fluoroscopically guided pedicle screw insertion.

STUDY DESIGN: An experimental model for the assessment of patient dose and associated radiogenic risks associated with pedicle screw internal fixation surgical procedures. OBJECTIVES: To provide data for the accurate determination of patient effective dose, gonadal dose, and entrance skin dose from fluoroscopically assisted pedicle screw insertion procedures and to investigate the potential of both stochastic and deterministic radiogenic effects to occur following such procedures. SUMMARY OF BACKGROUND DATA: There is increased concern on radiation exposure of patients undergoing fluoroscopically guided interventional procedures. METHODS: The cumulative screening time and dose area product, for each fluoroscopic projection used, were monitored in 20 patients undergoing pedicle screw internal fixation. The dose absorbed by each radiosensitive organ/tissue was determined from direct measurements obtained using an anthropomorphic phantom appropriately loaded with thermoluminescence dosimeters. RESULTS: An average pedicle screw insertion procedure requires 1.2 minutes and 2.1 minutes of fluoroscopic exposure along anteroposterior and lateral projections, respectively, resulting in a dose area product of 232 cGy cm and 568 cGy cm, correspondingly. Gender-specific normalized data for the determination of effective, gonadal, and entrance skin dose to patients undergoing fluoroscopically guided pedicle screw internal fixation procedures were derived. The effective dose from an average procedure was 1.52 and 1.40 mSv and the gonadal dose 0.67 and 0.12 mGy for female and male patients, respectively. The average radiogenic risks for fatal cancer and genetic defects were 115 and 4 per million of patients treated, respectively. Induction of skin injuries might be induced when fluoroscopy along the lateral projection is highly extended and the source to skin distance is kept low. CONCLUSIONS: Patient dose and radiogenic risks associated with an average pedicle screw internal fixation procedure are tolerable. However, for young patients with complex spinal disorders requiring extended fluoroscopy, radiogenic risks may be considerable. Present data may beused for estimation of effective dose, gonadal dose, and entrance skin exposure and associated radiogenic risks to patients undergoing fluoroscopically guided pedicle screw insertion in any institution.

Adult↗

PubMed2003

Treatment of closed unstable metacarpal fractures using percutaneous transverse fixation with Kirschner wires.

BACKGROUND: The vast majority of metacarpal bone fractures are stable and are treated conservatively; however, when surgical intervention is to be preferred, many different operative procedures have been described. The purpose of this prospective study was to assess the anatomic and functional outcome of percutaneous transverse fixation with Kirschner wires (K-wires) of closed metacarpal neck, shaft. and intra-articular fractures of the base of the fifth metacarpal. METHODS: Twenty-four consecutive patients with 25 closed metacarpal fractures were treated with this technique between 1999 and 2001. Under fluoroscopy, closed reduction and osteosynthesis with three K-wires, one proximally and two distally, was performed on the fracture site. All patients were reviewed clinically and radiologically after 3 weeks, 6 weeks, and 3 months. RESULTS: The postoperative dorsal angulation ranged from 0 to 3 degrees. No measurable metacarpal shortening was observed. Callus formation was obvious in all fractures at 6 weeks. No complications were recorded, and all patients were cosmetically and functionally satisfied. CONCLUSION: Treatment of closed metacarpal neck, shaft, and intra-articular fractures of the base of the fifth metacarpal with percutaneous transverse pinning, using two K-wires distally and one proximally, has shown excellent functional and anatomic outcome.

Adult↗

PubMed2003

Functional evaluation after primary flexor tendon repair in zone II.

The purpose of this prospective study was to evaluate the results of primary treatment of flexor tendon laceration in zone II according to Verdan's zone system. Special emphasis was given to the postoperative rehabilitation program. Nineteen patients (23 fingers) with laceration of the flexor tendons in zone II were treated operatively. Twelve males and seven females were included in the study. Their mean age was 28 years (range, 16 to 50 years). In 12 cases a concomitant laceration of the digital nerve was present. In all cases primary repair of all injured tendons and nerves was performed and a dorsal splint was applied. On the third to fifth postoperative day an exercise program commenced involving passive flexion-active extension of the injured fingers. Eighteen (22 fingers) of 19 patients completed the follow-up. The results were evaluated according to Strickland's original classification system. The result was excellent in 15 cases, good in five and fair in two. After primary repair of injured flexor tendons, a program of close follow-up, early protected motion and unrestricted motion of the interphalangeal joints offers the best chance of restoring optimal function to the hand.

Adolescent↗