Omission of Planning CT Reduces Patient Radiation Exposure during CT-Guided Bone Marrow Biopsy and Aspiration

The purpose of this study is to evaluate the impact of eliminating a preprocedural planning computed tomography during CT-guided bone marrow biopsy on the technical aspects of the procedure, including patient dose, sample quality, procedure time, and CT fluoroscopy usage. Retrospective analysis of 109 patients between 1 June 2018 and 1 January 2021 was performed. Patients were grouped based on whether they received a planning CT scan. Relative radiation exposure was measured using dose-length product (DLP). Secondary metrics included number of CT fluoroscopic acquisitions until target localization, total number of CT fluoroscopic acquisitions, biopsy diagnostic yield, and procedure time. A total of 43 bone marrow biopsies with planning CT scans (Group 1) and 66 bone marrow biopsies without planning CT scans (Group 2) were performed. The average total DLP for Group 1 and Group 2 was 268.73 mGy*cm and 50.92 mGy*cm, respectively. The mean radiation dose reduction between the groups was 81% (p < 0.0001). Significantly more CT fluoroscopy acquisitions were needed for needle localization in Group 2 than Group 1 (p < 0.0001). Total number of CT fluoroscopy acquisitions was four for Group 1 and eight for Group 2 (p = 0.0002). There was no significant difference between the groups in procedure time or diagnostic yield. Patients without a planning CT scan received more fluoroscopic CT acquisitions but overall were exposed to significantly less radiation without an increase in procedure time.

Radioablation of Upper Abdominal Malignancies by CT-Guided, Interstitial HDR Brachytherapy: A Multivariate Analysis of Catheter Placement Assisted by Ultrasound Imaging

Purpose To evaluate the use of ultrasound (US) during catheter placement in interstitial brachytherapy (iBT) of abdominal malignancies as an alternative to computed tomography (CT) fluoroscopy. Materials and Methods Catheter placement for CT-guided iBT was, if US visibility was sufficient, assisted by sonography in 52 consecutive patients with 82 lesions (liver N = 62; kidney N = 16; peritoneum N = 4) of various malignancies. We collected data on lesion visibility, location, depth, size, and dosimetry. Comparison of CT fluoroscopy versus US-assisted catheter placement was performed by Fisher’s exact test for frequencies and U-test for lesion visibility and dosimetric data. Factors predicting the utility of sonography were determined in a lesion-based multivariate regression analysis. A p-value < 0.05 was regarded as statistically significant. Results 150 catheters (1 to 6 per lesion; mean diameter 3.6 ± 2.4 cm) were implanted. CT fluoroscopy was used for 44 catheters, and US was used for 106 catheters. Lesion visibility assessed by 5-point Likert scale was significantly better in US (median 2 vs. 3; p = 0.011) and effective dose was significantly reduced if US guidance was applicable (median 1.75 vs. 8.19 mSv; p = 0.014). In a multivariate regression analysis, we identified increased lesion size and caudal location within the target organ to independently predict the utility of ultrasound in catheter placement for iBT. Conclusion Sonography is a helpful technique to assist CT-guided interstitial brachytherapy of upper abdominal malignancies. Especially for larger lesions localized in the lower liver segments or lower half of the kidney, superior visibility can be expected. As the effective dose of the patient is also reduced, radiation exposure of the medical staff may be indirectly lowered. Key Points: Citation Format

Successful treatment of a symptomatic unicameral calcaneus bone cyst by cement injection using a double needle technique under CT guidance: a case report

Simple bone cysts (SBCs) are benign cavitary lesions which most commonly affect adolescent males in the first two decades of life. They are mainly asymptomatic, but can manifest with pain or pathological fractures. A 16-year old girl presented with an 8-day history of pain and swelling over the right calcaneal region. On local examination, tenderness was the only noteworthy sign and all routine laboratory tests conducted revealed normal results. Despite numerous proposed methods for the management of calcaneus SBCs, the optimal approach towards these lesions remains controversial. Here, a novel method utilizing a minimally invasive technique is proposed to successfully manage these lesions. In an outpatient setting, under conscious sedation, two interosseous needles were simultaneously inserted into the cyst under the guidance of CT fluoroscopy. Without aspiration, a radiopaque bone cement mixture was injected into the cyst from one needle until the cessation of serosanguineous fluid efflux from the second needle. Over a one-year follow-up period, the patient recovered without any complications. Bone cement injection using a double needle technique under CT fluoroscopy guidance is a feasible and safe method to treat symptomatic unicameral calcaneal bone cysts.

Percutaneous Transhepatic Biopsy for Extrahepatic Lesions

Purpose The purpose was to assess the diagnostic accuracy and safety of percutaneous transhepatic biopsy for extrahepatic lesions. Materials and Methods Between January 2008 and December 2019, 26 patients (17 men and 9 women; median age, 60 years) underwent percutaneous transhepatic needle biopsy for extrahepatic lesions at our institution. Transhepatic biopsy was deemed appropriate compared with other biopsy routes or methods (i.e., endoscopic or surgical). The lesions were in the porta hepatis (n = 9), retroperitoneum (n = 6), right adrenal gland (n = 4), right kidney (n = 3), lesser omentum (n = 2), duodenum (n = 1), pleura (n = 1), and inferior vena cava (n = 1). The median maximal diameter of the lesions was 45.5 mm (range, 18–148 mm). Core-needle biopsy was performed in all patients. Eighteen-gauge and 21-G needles were used in 25 and one patient, respectively. Ultrasound was used for biopsy in 21 patients, and CT fluoroscopy was used in five patients. Postbiopsy tract embolization was performed in three patients. Technical success and diagnostic accuracy of the biopsy were evaluated. Complications were recorded using the systemic inflammation response (SIR) criteria. Results The pathological results of biopsy were carcinoma (n = 10), lymphoma (n = 9), and other diagnoses (n = 7). Technical success was obtained in all patients. The accurate diagnosis was achieved in 24 of the 26 patients (92.3%). A major complication, a bladder tamponade, was observed in one patient (3.8%) after biopsy of a right kidney lesion. A hematoma caused by iatrogenic renal injury likely obstructed the bladder outlet. Minor complications were observed in three patients (11.5%). Conclusions Percutaneous transhepatic biopsy for extrahepatic lesions is feasible with acceptable safety.

Percutaneous CT Fluoroscopy-Guided Core Needle Biopsy of Mediastinal Masses: Technical Outcome and Complications of 155 Procedures during a 10-Year Period

Purpose: To evaluate technical outcome, diagnostic yield and safety of computed tomographic fluoroscopy-guided percutaneous core needle biopsies in patients with mediastinal masses. Methods: Overall, 155 CT fluoroscopy-guided mediastinal core needle biopsies, performed from March 2010 to June 2020 were included. Size of lesion, size of needle, access path, number of success, number of biopsies per session, diagnostic yield, patient’s position, effective dose, rate of complications, tumor localization, size of tumor and histopathological diagnosis were considered. Post-interventional CT was performed, and patients observed for any complications. Complications were classified per the Society of Interventional Radiology (SIR). Results: 148 patients (age, 54.7 ± 18.2) underwent 155 CT-fluoroscopy-guided percutaneous biopsies with tumors in the anterior (114; 73.5%), middle (17; 11%) and posterior (24; 15.5%) mediastinum, of which 152 (98%) were technically successful. For placement of the biopsy needle, in 82 (52.9%) procedures a parasternal trajectory was chosen, in 36 (23.3%) a paravertebral access, in 20 (12.9%) through the lateral intercostal space and in 17 (11%) the thoracic anterior midline, respectively. A total of 136 (89.5%) of the biopsies were considered adequate for a specific histopathologic analysis. Total DLP (dose-length product) was 575.7 ± 488.8 mGy*cm. Mean lesion size was 6.0 ± 3.3 cm. Neoplastic pathology was diagnosed in 115 (75.7%) biopsies and 35 (23%) biopsy samples showed no evidence of malignancy. Minor complications were observed in 18 (11.6%) procedures and major pneumothorax requiring drainage insertion in 3 interventions (1.9%). Conclusion: CT fluoroscopy-guided percutaneous core needle biopsy of mediastinal masses is an effective and safe procedure for the initial assessment of patients with mediastinal tumors.

Occupational Radiation Dose to Eye Lenses in CT-Guided Interventions Using MDCT-Fluoroscopy

In computed tomography (CT)-guided interventions (CTIs), physicians are close to a source of scattered radiation. The physician and staff are at high risk of radiation-induced injury (cataracts). Thus, dose-reducing measures for physicians are important. However, few previous reports have examined radiation doses to physicians in CTIs. This study evaluated the radiation dose to the physician and medical staff using multi detector (MD)CT-fluoroscopy, and attempted to understand radiation-protection and -reduction methods. The procedures were performed using an interventional radiology (IVR)-CT system. We measured the occupational radiation dose (physician and nurse) using a personal dosimeter in real-time, gathered CT-related parameters (fluoroscopy time, mAs, CT dose index (CTDI), and dose length product (DLP)), and performed consecutive 232 procedures in CT-guided biopsy. Physician doses (eye lens, neck, and hand; μSv, average ± SD) in our CTIs were 39.1 ± 36.3, 23.1 ± 23.7, and 28.6 ± 31.0, respectively. Nurse doses (neck and chest) were lower (2.3 ± 5.0 and 2.4 ± 4.4, respectively) than the physician doses. There were significant correlations between the physician doses (eye and neck) and related factors, such as CT-fluoroscopy mAs (eye dose: r = 0.90 and neck dose: r = 0.83). We need to understand the importance of reducing/optimizing the dose to the physician and medical staff in CTIs. Our study suggests that physician and staff doses were not significant when the procedures were performed with the appropriate radiation protection and low-dose techniques.