Occupational radiation exposure from fluoroscopically guided percutaneous transhepatic biliary procedures

PURPOSE: The aim of this study was to determine occupational dose levels for projections commonly used in fluoroscopically guided percutaneous transhepatic biliary (PTB) drainage and stent placement procedures. METHODS: Exposure data from 71 consecutive PTB examinations were analyzed to determine average examination parameters for biliary drainage and stent placement procedures. An anthropomorphic phantom was exposed at three projections common in PTB interventions according to the actual geometric parameters recorded in the patient study. Scattered air-kerma dose rates were measured for neck, waist, and gonad levels at various sites in the interventional radiology laboratory. To produce technique- and instrumentation-independent data, dose rate values were converted to dose-area product (DAP)-normalized air-kerma values. In addition, sets of thermoluminescent dosimetry crystals were placed in both hands of the interventional radiologist to monitor doses during all PTB procedures. RESULTS: Isodose maps of DAP-normalized air-kerma doses in the interventional laboratory for projections commonly used in PTB procedures are presented. To facilitate effective dose estimation, normalized dosimetric data at the interventional radiologist's position are presented for left and right access drainage procedures, metallic stent placement only, and drainage and metallic stent placement in one-session procedures with and without under-couch shielding. Doses to the hands of interventional radiologists are presented for left and right transhepatic biliary access and metallic stent placement. CONCLUSIONS: Body level-specific normalized air-kerma distributions from commonly used projections in PTB procedures may be useful to accurately quantify dose, maximum workloads, and possible radiogenic risks delivered to medical personnel working in the interventional radiology laboratory. Normalized dose data presented will enable occupational exposure estimation from other institutions.     

Apheresis: another indication for radiologically placed central venous catheters.

OBJECTIVE: Apheresis is an important technique, used increasingly for a variety of conditions. It is sometimes performed via peripheral access because of concern over major complications associated with central venous catheter (CVC) placement. This study was to determine the safety and success of radiologic placement of CVCs for apheresis. METHODS: Data were collected prospectively for 278 CVCs placed under real-time sonographic or fluoroscopic guidance in the radiology department. Complications were noted in all cases; the number of passes required for venipuncture and whether this was achieved with a single wall puncture were noted in 265 cases; duration of catheterization and reason for removal of the catheter were recorded in all cases. The study group included 83 donors providing peripheral blood stem cells for allogeneic transplant. RESULTS: CVCs were successfully placed in all patients, 269 in the internal jugular and 9 in the femoral vein. In 87% of cases, only a single pass was required, and in 80% of cases venipuncture was achieved with a single anterior wall puncture. There was inadvertent but clinically insignificant arterial puncture in 6 cases (2%). In no case did this prevent CVC placement. Most catheters (211/274, 77%) were removed the same day. Only 3 catheters were removed prematurely (1%), 1 because of infection and 2 because of clotting. There was 1 case of venous bleeding. CONCLUSION: CVCs are safe for apheresis if real-time sonographic guidance is used for the puncture, guide wire and catheter placement are confirmed fluoroscopically, and the duration of catheterization is short.     

Single-centre review of radiologically guided percutaneous nephrostomy using "mixed" technique: success and complication rates

Aim

A review of complication and success rates of the “mixed” technique in percutaneous nephrostomy using both the Seldinger and one-step techniques in dilated and non-dilated systems.

Materials and methods

We retrospectively analysed 500 percutaneous nephrostomies in dilated an non-dilated systems in 353 patients from 2006 to 2007 (208 males (range 19-95 years), 127 females (range 27-91 years) and 21 children (range 3 months-16 years: 6 females, 15 males)). Percutaneous nephrostomy was considered successful if catheter was placed in renal pelvis and drained urine spontaneously. Successful percutaneous nephrostomies were classified as primary (renal system drained instantly) or postponed (drainage achieved within 24 h after initial failure). Number of complications was registered.

Results

All of the 500 nephrostomies were successful within 24 h (96.2% primary; 3.8% postponed). The success rate of primary nephrostomy in dilated and non-dilated systems was 98.2% and 82%, respectively. Major complications occurred in 0.45% and minor complications in 14.2%.

Conclusion

Percutaneous nephrostomy using the “mixed” technique is very successful in dilated systems, is not superior to other PCN techniques in non-dilated systems and has a very low rate of major complications.     

X线导向经皮骨穿刺活检

目的:探讨X线导向经皮骨穿刺活检对骨病的诊断价值。材料和方法:骨穿刺活检79例,通过观察X线片及CT确定活检的最佳部位。在X线导向下进行多点和不同浓度的骨穿刺活检取材。结果:79例行骨穿刺活检82次,其中3例穿刺2次。76例穿刺活检结果能作出诊断,阳性率为96.2％。没有发生并发症。结论:本法的优点是适应症广、简单、安全、快速、可靠、经济,并发症少及缩短诊断时间。医生在穿刺活检过程中不受X线辐射,而病人只有短暂的透视定位。     

Antibiotic bonded nephrostomy catheters for percutaneous nephrostomies

A prospective controlled trial of the effectiveness of a cefoxitin-bonded nephrostomy catheter was undertaken to determine the effectiveness of an antibiotic bonded catheter in decreasing the infectious complications of percutaneous nephrostomy. The study concludes that bonding of the antibiotic cefoxitin to percutanoeus nephrostomy catheters did not influence the incidence of bacteriuria or urinary tract infection. In addition, observations on the overall incidence of complications from percutaneous nephrostomy are made.     

Sonographically guided percutaneous biopsy of small (3 cm or less) masses

Traditionally, sonographically guided percutaneous needle biopsy has been used for the biopsy of large, superficial, and cystic masses. Today, however, many think that small, solid masses also can be biopsied accurately. Real-time sonographically guided biopsies of 126 consecutive solid masses that were less than or equal to 3.0-cm in diameter (less than or equal to 1.0 cm, 24; 1.1-2.0 cm, 42; 2.1-3.0 cm, 60) were performed to diagnose primary or secondary neoplasm. These masses were located in a variety of anatomic regions (abdomen, 92; neck, 31; breast, two; extremity, one). Clear visualization of the biopsy needle was accomplished by continuous real-time monitoring of the needle's position, primarily by using linear, phased-array transducers, large-caliber needles (18- to 19-gauge, when possible), and an echogenic screw stylet inserted coaxially within the biopsy needle. The correct cytologic/histologic diagnosis was established in 91% of the masses (less than or equal to 1.0 cm, 79%; 1.1-2.0 cm, 88%; 2.1-3.0 cm, 98%). No complications other than mild, localized discomfort were encountered. Our experience suggests that sonographically guided biopsy is a highly accurate and safe procedure that can be used to establish the diagnosis in solid masses that are 3.0 cm or less in diameter if proper techniques are used to clearly visualize the biopsy needle.     

Clinical radiation management for fluoroscopically guided interventional procedures

The primary goal of radiation management in interventional radiology is to minimize the unnecessary use of radiation. Clinical radiation management minimizes radiation risk to the patient without increasing other risks, such as procedural risks. A number of factors are considered when estimating the likelihood and severity of patient radiation effects. These include demographic factors, medical history factors, and procedure factors. Important aspects of the patient's medical history include coexisting diseases and genetic factors, medication use, radiation history, and pregnancy. As appropriate, these are evaluated as part of the preprocedure patient evaluation; radiation risk to the patient is considered along with other procedural risks. Dose optimization is possible through appropriate use of the basic features of interventional fluoroscopic equipment and intelligent use of dose-reducing technology. For all fluoroscopically guided interventional procedures, it is good practice to monitor radiation dose throughout the procedure and record it in the patient's medical record. Patients who have received a clinically significant radiation dose should be followed up after the procedure for possible deterministic effects. The authors recommend including radiation management as part of the departmental quality assurance program.     

超声引导下无水酒精硬化治疗肾囊肿(附68例分析)

目的：探讨超声引导下经皮穿刺注入无水酒精治疗肾囊肿的价值。方法：对68例有临床症状的肾囊肿患，行超声引导下肾囊肿穿刺无水酒精硬化治疗并随访观察。结果：治疗有效率为97．06％，无一例出现并发症，多囊肾的治疗有也有较满意的效果。结论：超声引导经皮穿刺无水酒精硬化治疗肾囊肿安全有效，值得推广应用。