Challenges in abdominal/pelvic biopsy techniques

Safety and accuracy of aortic and periaortic CT-guided percutaneous core needle biopsy

PURPOSE

The purpose of this study was to determine the safety and accuracy of aortic and periaortic computed tomography (CT)-guided percutaneous core needle biopsy performed at a single center over 12 years.

MATERIALS AND METHODS

A retrospective review was conducted of cases performed between February 2010 and August 2022 in which the biopsied region was in direct contact with the aorta or great vessels including the pericardium and common iliac arteries. Clinical notes were reviewed for any early or delayed complications following the procedure, which if present were graded using the National Institute of Health's Common Terminology Criteria for Adverse Events, version 5.0. Pathology results were compared to subsequent outside biopsy results or follow-up surgical pathology, if available, as well as subsequent clinical decision making and/or clinical course, to determine concordance. Sensitivity, specificity, predictive value, and accuracy (indicative of diagnostic yield) were calculated.

RESULTS

32 core needle biopsies were reviewed from 30 patients (average lesion longest diameter 3.1 cm, range 0.5-10.9 cm; average needle proximity to the vessel endothelium or deep side of the pericardium 1.0 cm, range 0.3-1.8 cm). Complications occurred in 46.9% of cases (15/32), 93.3% (14/15) of which were minor and included small amounts of bleeding or pain. One patient developed a small nonemergent pneumothorax. Of biopsies obtained, 96.9% provided adequate tissue for diagnosis (31/32). When evaluating concordance between pathological and final diagnosis, sensitivity was 94.7% and specificity was 83.3%; positive and negative predictive value were 90.0% and 90.9%, respectively. Accuracy (diagnostic yield) of biopsy was 90.3%.

CONCLUSION

CT-guided percutaneous aortic and periaortic core needle biopsies are safe and efficacious procedures with high diagnostic yield.

Prospective Randomized Trial for Image-Guided Biopsy Using Cone-Beam CT Navigation Compared with Conventional CT

PURPOSE

To compare cone-beam computed tomography (CT) navigation vs conventional CT image guidance during biopsies.

MATERIALS AND METHODS

Patients scheduled for image-guided biopsies were prospectively and randomly assigned to conventional CT guidance vs cone-beam CT navigation. Radiation dose, accuracy of final needle position, rate of histopathologic diagnosis, and number of needle repositions to reach the target (defined as pullback to adjust position) were compared.

RESULTS

A total of 58 patients (mean age, 57 y; 62.1% men) were randomized: 29 patients underwent 33 biopsies with CT guidance and 29 patients with 33 lesions underwent biopsy with cone-beam CT navigation. The average body mass index (BMI) was similar between groups, at 28.8 kg/m(2) ± 6.55 (P = .18). There was no difference between groups in terms of patient and lesion characteristics (eg, size, depth). The average lesion size was 29.1 ± 12.7mm for CT group vs 32.1mm ±16.8mm for cone-beam CT group (P < 0.59). Location of lesions was equally divided between the 2 groups, 20 lung lesions, 18 renal lesions and 20 other abdominal lesions. Mean number of needle repositions in the cone-beam CT group was 0.3 ± 0.5, compared with 1.9 ± 2.3 with conventional CT (P < .001). The average skin entry dose was 29% lower with cone-beam CT than with conventional CT (P < .04 accounting for BMI). The average estimated effective dose for the planning scan from phantom data was 49% lower with cone-beam CT vs conventional CT (P = .018). Accuracy, defined as the difference between planned and final needle positions, was 4.9 mm ± 4.1 for the cone-beam CT group, compared with 12.2 mm ± 8.1 for conventional CT (P < .001). Histopathologic diagnosis rates were similar between groups, at 90.9% for conventional CT and 93.9% for cone-beam CT (P = .67).

CONCLUSIONS

Cone-beam CT navigation for biopsies improved targeting accuracy with fewer needle repositions, lower skin entry dose, and lower effective dose for planning scan, and a comparable histopathologic diagnosis rate.

Assessing the reliability of MRI-CBCT image registration to visualize temporomandibular joints

OBJECTIVES

To evaluate image quality of two methods of registering MRI and CBCT images of the temporomandibular joint (TMJ), particularly regarding TMJ articular disc-condyle relationship and osseous abnormality.

METHODS

MR and CBCT images for 10 patients (20 TMJs) were obtained and co-registered using two methods (non-guided and marker guided) using Mirada XD software (Mirada Medical Ltd, Oxford, UK). Three radiologists independently and blindly evaluated three types of images (MRI, CBCT and registered MRI-CBCT) at two times (T1 and T2) on two criteria: (1) quality of MRI-CBCT registrations (excellent, fair or poor) and (2) TMJ disc-condylar position and articular osseous abnormalities (osteophytes, erosions and subcortical cyst, surface flattening, sclerosis).

RESULTS

75% of the non-guided registered images showed excellent quality, and 95% of the marker-guided registered images showed poor quality. Significant difference was found between the non-guided and marker-guided registration (χ(2) = 108.5; p < 0.01). The interexaminer variability of the disc position in MRI [intraclass correlation coefficient (ICC) = 0.50 at T1, 0.56 at T2] was lower than that in MRI-CBCT registered images [ICC = 0.80 (0.52-0.92) at T1, 0.84 (0.62-0.93) at T2]. Erosions and subcortical cysts were noticed less frequently in the MRI-CBCT images than in CBCT images.

CONCLUSIONS

Non-guided registration proved superior to marker-guided registration. Although MRI-CBCT fused images were slightly more limited than CBCT alone to detect osseous abnormalities, use of the fused images improved the consistency among examiners in detecting disc position in relation to the condyle.