Safety of bone marrow aspiration and biopsy in severely thrombocytopenic patients.

PURPOSE: To assess the safety of fluoroscopically guided drill-assisted bone marrow aspirate and biopsy in severely thrombocytopenic patients. MATERIALS AND METHODS: The study was approved by the IRB with waiver of informed consent. Retrospective review of 111 bone marrow aspirate and biopsies (BMAB) performed in 94 patients who received a CT scan which included the pelvis and biopsy site within the 7 days following the BMAB. The 94 patients were subdivided based on their platelet count: severe thrombocytopenia (< 20 platelets × 109/L), thrombocytopenia (20-50 platelets × 109/L), and control (> 50 platelets × 109/L). The procedure report was reviewed for sedation time, aspirate volume, and aggregate size of core biopsy specimens. The electronic medical record was reviewed for specimen adequacy; pathologic diagnosis; body mass index; pre- and post-procedure labs including platelet count, hemoglobin (HGB), hematocrit (HCT), prothrombin time (PT), and international normalized ratio (INR) levels; post-procedural transfusion; and complications including mortality at 30 and 90 days. CT scans were independently reviewed by 2 fellowship-trained radiologists for the presence of post-procedural hemorrhage. RESULTS: There was no significant difference in CT-identified post-procedural hematoma, or change in the hemoglobin and hematocrit levels pre- and post-procedure between the three groups. There was no significant difference in complication rate or all-cause mortality. There was a significant difference in transfusion at 30 days with thrombocytopenic and severely thrombocytopenic patients more likely to receive transfusion within the 30 days post-procedure. CONCLUSION: Fluoroscopically guided BMAB can be safely performed in patients with severe thrombocytopenia.

Percutaneous CT-Guided Core Needle Biopsies of Head and Neck Masses: Technique, Histopathologic Yield, and Safety at a Single Academic Institution.

BACKGROUND AND PURPOSE: CT-guided head and neck biopsies can be challenging due to the anatomy and adjacent critical structures but can often obviate the need for open biopsy. A few studies and review articles have described approaches to biopsy in the head and neck. This retrospective study evaluated technical considerations, histopathologic yield, and safety in CT-guided head and neck core needle biopsies. MATERIALS AND METHODS: A retrospective review of head and neck biopsies performed from January 2013 through December 2019 was conducted. Clinical diagnosis and indication, patient demographics, mass location and size, biopsy needle type, technical approach, dose-length product, sedation details, complications, diagnostic histopathologic yield, and the use of iodinated contrast were recorded for each case. RESULTS: A total of 27 CT-guided head and neck core needle biopsies were performed in 26 patients. The diagnostic sample rate was 100% (27/27). A concordant histopathologic diagnosis was obtained in 93% (25/27) of cases. There was a single complication of core needle biopsy, a small asymptomatic superficial hematoma. CONCLUSIONS: Percutaneous CT-guided biopsy of deep masses in the head and neck is safe and effective with careful biopsy planning and has a high diagnostic yield that can obviate the need for open biopsy.

Percutaneous CT-Guided Skull Biopsy: Feasibility, Safety, and Diagnostic Yield.

BACKGROUND AND PURPOSE: Although percutaneous musculoskeletal biopsies are routinely performed in the axial and appendicular skeleton, there are no published data on the systematic evaluation of the feasibility, safety, and diagnostic accuracy of percutaneous skull biopsy. In certain clinical encounters such as patients with primary skull tumors or patients with known cancer and isolated skull lesions suspected of calvarial metastasis or synchronous primary tumor, percutaneous skull biopsy may be considered a viable option. The purpose of this study was to evaluate the feasibility, safety profile, and diagnostic yield of percutaneous CT-guided skull biopsy. MATERIALS AND METHODS: Percutaneous CT-guided skull biopsy was performed in 14 patients. Patient demographics, cancer history, indication for initial imaging, imaging technique of diagnosis, skull tumor anatomic location, and final histologic diagnosis were documented. Preprocedural imaging of each skull lesion was reviewed to determine tumor size and characteristics. Procedural notes were reviewed to determine the total conscious sedation time or anesthesia time, type of biopsy needle, and the number and length of obtained core specimens. Procedure-related complications were also documented according to the Society of Interventional Radiology classification. RESULTS: All CT-guided percutaneous skull biopsy procedures were performed as preoperatively planned and were technically successful. Procedures were performed with the patient under conscious sedation in 93% (13/14) of cases. Definitive histologic diagnosis was achieved in 86% (12/14) of cases. There were no acute or delayed procedure-related complications. CONCLUSIONS: The results of this retrospective initial study suggest that percutaneous CT-guided skull biopsy is feasible with an excellent safety profile, affords a high diagnostic yield for histologic characterization, and may obviate more invasive open skull biopsies.

Simultaneous Bipedicular Radiofrequency Ablation Combined with Vertebral Augmentation for Local Tumor Control of Spinal Metastases.

BACKGROUND AND PURPOSE: Percutaneous radiofrequency ablation combined with vertebral augmentation has emerged as a minimally invasive treatment for patients with vertebral metastases who do not respond to or have contraindications to radiation therapy. The prevalence of posterior vertebral body metastases presents access and treatment challenges in the unique anatomy of the spine. The purpose of this study was to evaluate the safety and efficacy of simultaneous bipedicular radiofrequency ablation using articulating bipolar electrodes combined with vertebral augmentation for local tumor control of spinal metastases. MATERIALS AND METHODS: Imaging-guided simultaneous bipedicular radiofrequency ablation combined with vertebral augmentation was performed in 27 patients (33 tumors) with vertebral metastases selected following multidisciplinary consultations, to achieve local tumor control in this retrospective study. Tumor characteristics, procedural details, and complications were documented. Pre- and postprocedural cross-sectional imaging was evaluated to assess local tumor control rates. RESULTS: Thirty-three tumors were successfully ablated in 27 patients. Posterior vertebral body or pedicle involvement or both were present in 94% (31/33) of cases. Sixty-seven percent (22/33) of the tumors involved ≥75% of the vertebral body volume. Posttreatment imaging was available for 79% (26/33) of the treated tumors. Local tumor control was achieved in 96% (25/26) of tumors median imaging follow up of 16 weeks. No complications were reported, and no patients had clinical evidence of metastatic spinal cord compression at the treated levels. CONCLUSIONS: Simultaneous bipedicular radiofrequency ablation combined with vertebral augmentation is safe and effective for local tumor control of vertebral metastases. Articulating bipolar electrodes enable the placement and proximity necessary for optimal confluence of the ablation zones. Local tumor control may lead to more durable pain palliation, prevent disease progression, and reduce skeletal-related events of the spine.

Percutaneous CT-Guided Biopsies of the Cervical Spine: Technique, Histopathologic and Microbiologic Yield, and Safety at a Single Academic Institution.

BACKGROUND AND PURPOSE: Cervical spine biopsies can be challenging due to the anatomy and the adjacent critical structures. Percutaneous image-guided biopsies can obviate the need for an open biopsy, however there have been few studies looking at the approaches, safety, and efficacy of percutaneous cervical spine biopsies. This retrospective study evaluated technical considerations, histopathologic and microbiologic yield, and safety in CT-guided cervical bone biopsies. MATERIALS AND METHODS: A retrospective review of cervical bone and/or bone/disc biopsies performed from January 2010 to January 2017 was included in this study. Clinical diagnosis and indication, patient demographics, biopsy location, biopsy needle type, technical approach, lesion size, dose-length product, conscious sedation details, complications, and diagnostic histopathologic and/or microbiologic yield were recorded for each case and summarized. RESULTS: A total of 73 patients underwent CT-guided cervical bone biopsies. Fifty-three percent (39/73) were for clinical/imaging concern for infection and 47% (34/73) were for primary tumors or metastatic disease. Thirty-four percent (25/73) were of the inferior cervical spine (ie, C6 and C7). A sufficient sample was obtained for histopathologic and microbiologic analyses in 96% (70/73) of the biopsies. Forty-six percent (18/39) of those samples taken for infection had positive cultures. Two intraprocedural complications occurred in which the patients became hypotensive during the procedure without long-term complications. CONCLUSIONS: Percutaneous CT-guided biopsy of the cervical spine is an effective and safe procedure with high diagnostic yield and can obviate open procedures for histopathologic and microbiologic analyses of patients with clinical and imaging findings concerning for infection or primary and metastatic osseous lesions.

Percutaneous Spinal Ablation in a Sheep Model: Protective Capacity of an Intact Cortex, Correlation of Ablation Parameters with Ablation Zone Size, and Correlation of Postablation MRI and Pathologic Findings.

BACKGROUND AND PURPOSE: Despite the growing use of percutaneous ablation therapy for the treatment of metastatic spine disease, several issues have yet to be fully addressed. Our aims were to determine whether the vertebral body cortex protects against ablation-induced spinal cord injury; correlate radiofrequency, cryo-, and microwave ablation parameters with resulting spinal ablation zone dimensions and describe normal spinal marrow postablation changes on MR imaging. MATERIALS AND METHODS: Ten thoracolumbar vertebrae in 3 sheep were treated with radiofrequency ablation, cryoablation, or microwave ablation under fluoroscopic guidance. Technique parameters were chosen to produce ablation zones that exceeded the volume of the vertebral bodies in sheep 1 and were confined to the vertebrae in sheep 2 and 3. Expected ablation zone dimensions were based on data provided by the device manufacturers. Postablation MR imaging was performed at 48 hours (sheep 1) or 7 days (sheep 2 and 3). RESULTS: In sheep 1, cryoablation and microwave ablations extended into the spinal canal and caused histologically confirmed neurologic injury, but radiofrequency ablation did not. The mean difference between the lengths of the radiofrequency ablation zone dimensions measured on gross pathology compared with those expected was 9.6 ± 4.1 mm. The gross pathologic cryo- and microwave ablation zone dimensions were within 1 mm of those expected. All modalities produced a nonenhancing ablation zone with a rim of enhancement, corresponding histologically to marrow necrosis and hemorrhagic congestion. CONCLUSIONS: An intact cortex appears to protect against radiofrequency ablation-induced spinal cord injury, but not against non-impedance-based modalities. Ablation dimensions produced by microwave and cryoablation are similar to those expected, while radiofrequency ablation dimensions are smaller. Ablation of normal marrow produces a rim of enhancement at the margin of the ablation zone on MR imaging.

Spine Cryoablation: Pain Palliation and Local Tumor Control for Vertebral Metastases.

BACKGROUND AND PURPOSE: Percutaneous cryoablation has emerged as a minimally invasive technique for the management of osseous metastases. The purpose of this study was to assess the safety and effectiveness of percutaneous imaging-guided spine cryoablation for pain palliation and local tumor control for vertebral metastases. MATERIALS AND METHODS: Imaging-guided spine cryoablation was performed in 14 patients (31 tumors) with vertebral metastases refractory to conventional chemoradiation therapy or analgesics, to achieve pain palliation and local tumor control in this retrospective study. Spinal nerve and soft-tissue thermal protection techniques were implemented in all ablations. Patient response was evaluated by a pain numeric rating scale administered before the procedure and 1 week, 1 month, and 3 months after the procedure. Pre- and postprocedural analgesic requirements (expressed as morphine-equivalent dosages) were also analyzed at the same time points. Pre- and postprocedural cross-sectional imaging was evaluated in all patients to assess local control (no radiographic evidence of disease at the treated sites). Complications were monitored. Analysis of the primary end points was undertaken via paired-comparison procedures by using the Wilcoxon signed rank test. RESULTS: Thirty-one tumors were ablated in 14 patients (9 women and 5 men; 20-73 years of age; mean age, 53 years). The most common tumor location was in the lumbar spine (n = 14, 45%), followed by the thoracic spine (n = 8, 26%), sacrum (n = 6, 19%), coccyx (n = 2, 6%), and cervical spine (n = 1, 3%). There were statistically significant decreases in the median numeric rating scale score and analgesic usage at 1-week, 1-month, and 3-month time points (P < .001 for all). Local tumor control was achieved in 96.7% (30/31) of tumors (median follow-up, 10 months). Two patients had transient postprocedural unilateral lower extremity radiculopathy and weakness. CONCLUSIONS: Percutaneous imaging-guided spine cryoablation is a safe and effective treatment for pain palliation and local tumor control for vertebral metastases.

Selective secretion of protein kinase C isozymes by thrombin-stimulated human platelets.

The protein kinase C (PKC) was secreted from thrombin-stimulated human platelets in a time- and dose-dependent manner. The PKC specific inhibitors Ro31-8220 (0.05 microM) and GF 109203X (0.5 microM) totally inhibited the secreted kinase activity. Western blot analysis of the secretory components showed reactivity to PKCalpha, PKCbetaII, and PKCdelta antibodies, but not to PKCbetaI, and p42/44 MAPK, although they were present in lysed platelets. The fractionation of platelets secreted components showed that PKC activity increased in both soluble and microparticle fractions after thrombin treatments. This is the first report demonstrating that activated human platelets selectively secrete protein kinase C isozymes. Protein kinase C secreted by platelets in this unique manner may have an extracellular role in the plasma, and may regulate cellular functions, including remodeling of vascular endothelial cells.