Pneumothorax and pulmonary hemorrhage after C-arm cone-beam computed tomography-guided percutaneous transthoracic lung biopsy: incidence, clinical significance, and correlation.

OBJECTIVE: This study aimed to assess the incidence and clinical significance of pneumothorax (PTX) and pulmonary hemorrhage (PH) after percutaneous transthoracic lung biopsy (PTLB) guided by C-arm cone-beam computed tomography (CBCT). Furthermore, this study aimed to examine the relationships between PTX and PH with demographics, clinical characteristics, imaging, and PTLB parameters. METHODS: A retrospective analysis was conducted on 192 patients who underwent PTLB at our hospital between January 2019 and October 2022. Incidences of PTX and PH were recorded. PTX was considered clinically significant if treated with chest tube insertion (CTI), and PH if treated with bronchoscopes or endovascular treatments. The various factors on PTX and PH were analyzed using the Chi-squared test and Student t-test. Logistic regression analyses were then used to determine these factors on the correlation to develop PTX and PH. RESULTS: PTX occurred in 67/192 cases (34.9%); CTI was required in 5/67 (7.5%). PH occurred in 63/192 cases (32.8%) and none of these cases required bronchoscopes or endovascular treatments. Lesion diameter (ORPTX = 0.822; ORPH = 0.785), presence of pulmonary emphysema (ORPH = 2.148), the number of samples (ORPH = 1.834), the use of gelfoam (ORPTX = 0.474; ORPH = 0.341) and ablation (ORPTX = 2.351; ORPH = 3.443) showed statistically significant correlation to PTX and PH. CONCLUSIONS: CBCT-guided PTLB is a safe and effective method for performing lung biopsies. The use of gelfoam has been shown to reduce the occurrence of PTX and PH. However, caution should be exercised when combining radiofrequency ablation with PTLB, as it may increase the risk of PTX and PH.

Is Proximal Triangular Fixation Better than the Conventional Method in Adult Spinal Deformity Surgery?

In adult spinal deformity (ASD) surgery, one of the key factors working to prevent proximal junctional kyphosis is the proximal anchor. The aim of this study was to compare clinical and radiographic outcomes of triangular fixation with conventional fixation as proximal anchoring techniques in ASD surgery. We retrospectively evaluated 54 patients who underwent corrective spinal fusion for ASD. Fourteen patients underwent proximal triangular fixation (Group T; average 74.6 years), and 40 patients underwent the conventional method (Group C; average 70.5 years). Clinical and radiographic outcomes were assessed using visual analogue scale (VAS) values for back pain and the Oswestry disability index (ODI). Radiographic evaluation was also collected preoperatively and postoperatively. Surgical times and intraoperative blood loss of the two groups were not significantly different (493 vs 490 min, 1,260 vs 1,173 mL). Clinical outcomes such as VAS and ODI were comparable in the two groups. Proximal junctional kyphosis in group T was slightly lower than that of group C (28.5% vs 47.5%, p=0.491). However, based on radiology, proximal screw pullout occurred significantly less frequently in the triangular fixation group than the conventional group (0.0% vs 22.5%, p=0.049). Clinical outcomes in the two groups were not significantly different.

3D C-arm navigated acromioclavicular joint stabilization.

INTRODUCTION: Surgical treatment options for acromioclavicular joint separations are varied. Frequently, suspension devices (SD) are inserted for stabilization under arthroscopic view. This study investigates the feasibility and accuracy of three-dimensional (3D) digital-volume-tomography (DVT) C-arm navigated implantation with regard to the general trend toward increasingly minimally invasive procedures. MATERIALS AND METHODS: The implantation of a TightRope® suture button system (SD) via a navigated vertical drill channel through the clavicle and coracoid was investigated in 10 synthetic shoulder models with a mobile isocentric C-arm image intensifier setup in the usual parasagittal position. Thereby, in addition the placement of an additive horizontal suture cerclage via a navigated drill channel through the acromion was assessed. RESULTS: All vertical drill channels in the Coracoclavicular (CC) direction could be placed in a line centrally through the clavicle and the coracoid base. The horizontal drill channels in the Acromioclavicular (AC) direction ran strictly in the acromion, without affecting the AC joint or lateral clavicle. All SD could be well inserted and anchored. After tensioning and knotting of the system, the application of the horizontal AC cerclage was easily possible. The image quality was good and all relevant structures could be assessed well. CONCLUSION: Intraoperative 3D DVT imaging of the shoulder joint using a mobile isocentric C-arm in the usual parasagittal position to the patient is possible. Likewise, DVT navigated SD implantation at the AC joint in CC and AC direction on a synthetic shoulder model. By combining both methods, the application in vivo could be possible. Further clinical studies on feasibility and comparison with established methods should be performed.

A Novel Technique for Basilar Invagination Treatment in a Patient with Klippel-Feil Syndrome: A Clinical Example and Brief Literature Review.

Objectives and Background: To present a novel technique of treatment for a patient with basilar invagination. Basilar invagination (BI) is a congenital condition that can compress the cervicomedullary junction, leading to neurological deficits. Severe cases require surgical intervention, but there is debate over the choice of approach. The anterior approach allows direct decompression but carries high complication rates, while the posterior approach provides indirect decompression and offers good stability with fewer complications. Materials and Methods: A 15-year-old boy with severe myelopathy presented to our hospital with neck pain, bilateral upper limb muscle weakness, and hand numbness persisting for 4 years. Additionally, he experienced increased numbness and gait disturbance three months before his visit. On examination, he exhibited hyperreflexia in both upper and lower limbs, muscle weakness in the bilateral upper limbs (MMT 4), bilateral hypoesthesia below the elbow and in both legs, mild urinary and bowel incontinence, and a spastic gait. Radiographs revealed severe basilar invagination (BI). Preoperative images showed severe BI and that the spinal cord was severely compressed with odontoid process. Results: The patient underwent posterior surgery with the C-arm free technique. All screws including occipital screws were inserted into the adequate position under navigation guidance. Reduction was achieved with skull rotation and distraction. A follow-up at one year showed the following results: Manual muscle testing results and sensory function tests showed almost full recovery, with bilateral arm recovery (MMT 5) and smooth walking. The cervical Japanese Orthopedic Association score of the patient improved from 9/17 to 16/17. Postoperative images showed excellent spinal cord decompression, and no major or severe complications had occurred. Conclusions: Basilar invagination alongside Klippel-Feil syndrome represents a relatively uncommon condition. Utilizing a posterior approach for treating reducible BI with a C-arm-free technique proved to be a safe method in addressing severe myelopathy. This novel navigation technique yields excellent outcomes for patients with BI.

Preliminary clinical observation of double C-arm digital subtraction angiography guidance during transjugular intrahepatic portosystemic shunt placement.

BACKGROUND: This study aimed to investigate the safety, preliminary clinical experience, and technical advantages of double C-arm digital subtraction angiography -assisted portal vein puncture for transjugular intrahepatic portosystemic shunt. METHODS: Clinical data of 25 patients with portal hypertension caused by liver cirrhosis were retrospectively analyzed from January 2021 to June 2022. The fluoroscopy time, puncture time, mean portosystemic pressure gradient, dose area product, and intraoperative and postoperative complications were recorded. RESULTS: Transjugular intrahepatic portosystemic shunt was performed in all 25 patients, with a success rate of 100%. The fluoroscopy time, puncture time, and dose area product were 33.6 ± 8.5 min, 9.1 ± 5.7 min, and 126 ± 53 Gy·cm2, respectively. The mean portosystemic pressure gradient decreased from 22.5 ± 6.3 mmHg to 10.5 ± 2.3 mmHg (p < 0.01). No serious intraoperative and postoperative complications were found. CONCLUSION: Double C-arm digital subtraction angiography-assisted portal vein puncture is safe and feasible in transjugular intrahepatic portosystemic shunt operation. It can reduce the difficulty of the operation and possesses evident technical advantages.

Ultrasound Guidance Combined with C-Arm Fluoroscopy in Selective Semilunar Ganglion Radiofrequency Thermocoagulation Through the Foramen Ovale for Trigeminal Neuralgia: A Randomized Controlled Trial.

OBJECTIVE: To explore the clinical value of ultrasound guidance combined with C-arm guidance during selective semilunar ganglion radiofrequency thermocoagulation via the foramen ovale for trigeminal neuralgia. METHODS: This study enrolled 48 patients diagnosed with trigeminal neuralgia between January 2021 and December 2021 in the Department of Pain Management at Xuanwu Hospital. Patients were randomly and equally divided into a C-arm-only group and an ultrasound-combined-with-C-arm (ultrasound+C-arm) group, according to a random number table. After exclusions, 42 patients were analyzed. Of these, 21 patients underwent selective semilunar ganglion radiofrequency thermocoagulation via the foramen ovale guided by the C-arm alone, whereas 21 patients underwent the same procedure guided by ultrasound combined with C-arm. The number of punctures, the amount of time elapsed until the target area of the semilunar ganglion was punctured, the cumulative dose of radiation exposure, and puncture-related complications were recorded during the operation. Numerical rating scale scores and radiofrequency thermocoagulation-related complications were evaluated preoperatively and at 1 day, 3 days, 7 days, 1 month, and 3 months after surgery. RESULTS: The number of punctures, the amount of time elapsed until the target area of the semilunar ganglion was punctured, and the cumulative dose of radiation exposure were all lower in the ultrasound+C-arm group than in the C-arm-only group (all P < 0.05). No significant differences were found in numerical rating scale scores and radiofrequency thermocoagulation-related complications between the two groups (P > 0.05). No puncture-related complications occurred in either of the groups. CONCLUSION: Ultrasound guidance combined with C-arm guidance could be safely used for puncturing the semilunar ganglion via the foramen ovale, with more efficiency and less radiation exposure than C-arm guidance alone.

Fluoroscopy-Assisted Freehand Versus 3D-Navigated Imaging-Assisted Pedicle Screw Insertion: A Multicenter Study.

INTRODUCTION: Pedicle screw placement is a widely accepted surgical procedure for spinal fixation. Despite increases in knowledge about and expertise in pedicle screw insertion techniques, overall reported screw misplacement rates are still high. Spinal neuronavigation and intraoperative computed tomography (CT) imaging improves the accuracy and safety of pedicle screw placement through the continuous monitoring of screw trajectory. The purpose of this study is to compare pedicle screw placement under an O-arm intraoperative imaging system assisted by the StealthStation navigation system with screw placement under conventional fluoroscopy (C-arm). METHODS: For 222 patients, 1288 implanted pedicle screws in total were evaluated between 2018 and 2020. All patients underwent pedicle screw placement in the thoracic and lumbosacral regions through a posterior approach. Moreover, 107 patients (48.2%), 48 men and 59 women, underwent freehand screw placement under conventional fluoroscopy (C-arm group), whereas 115 patients (51.8%), 53 men and 62 women, underwent pedicle screw insertion under O-arm guidance with the help of the StealthStation neuronavigation system (Medtronic Navigation, Louisville, CO, USA) (O-arm group). Data were recorded and retrospectively analyzed. The accuracy of pedicle screw placement was postoperatively examined by using CT imaging and analyzed according to the Gertzbein-Robbins classification. RESULTS: Of the 1288 pedicle screws, 665 (51.6%) were placed with C-arm image-guided assistance with a mean of 6.21 ± 2.1 screws per patient and 643 (48.4%) with O-arm image-guided assistance with a mean of 5.59 ± 1.6 screws. The average time for the screw placement procedure was 3:57 ± 1:07 h in the C-arm group and 4:21 ± 1:41 h in the O-arm group. A correct screw placement was detected in 92.78% of patients in the C-arm group and in 98.13% of patients in the O-arm group. Medial cortical breach was shown in 13 Grade B screws (1.95%), 19 Grade C (2.86%), 14 Grade D (2.11%), and two Grade E (0.3%) in the C-arm group, whereas this was shown in 11 Grade B screws (1.71%) and one Grade C (0.16%) in the O-arm group. Lateral breach occurred in eight screws in both groups. Anterior vertebral body breach was shown in eight screws in the C-arm group, whereas it was shown in four screws in the O-arm group. Reoperation for screw misplacement was mandatory in five patients in the C-arm group and two patients in the O-arm group. CONCLUSION: Pedicle screw placement under an O-arm intraoperative imaging system assisted by spinal navigation showed greater accuracy compared with placement under conventional fluoroscopic control, thus avoiding the onset of major postoperative complications. Notably, a reduction in medial and anterior breaches has been demonstrated.

Surgical outcomes of intraoperative O-arm versus C-arm fluoroscopy in occipitocervical fixation: a retrospective analysis.

PURPOSE: This study aims to compare the effect of using O-arm and C-arm fluoroscopy on the surgical outcomes of occipitocervical fixation. METHODS: The study included patients who underwent occipitocervical fixation using O-arm or C-arm between 2005 and 2021. Of 56 patients, 34 underwent O-arm-assisted surgery (O-group) and 22 underwent C-arm-assisted surgery (C-group). We assessed surgical outcomes, including operative time, intraoperative blood loss, perioperative complications, and bone union. RESULTS: Almost half of the patients had rheumatoid arthritis-related disorders in both groups. Sixteen cases (47.1%) in the O-group and 12 cases (54.5%) in the C-group were fixed from occipito (Oc) to C3, 12 cases (38.2%) in the O-group and 7 cases (31.8%) in the C-group from Oc to C4-7, 5 cases (14.7%) in the O-group, and 3 cases (13.6%) in the C-group from Oc to T2 (p = 0.929). There was no significant difference in operative time (p = 0.239) and intraoperative blood loss (p = 0.595) between the two groups. Dysphagia was the most common complication in both groups (O-group vs. C-group, 11.7% vs. 9.1%). Regarding implant-related complications, occipital plate dislodgement was observed in four cases (18.2%) in the C-group (p = 0.02). The bone union rate was 96.3% in the O-group and 93.3% in the C-group (P = 1). CONCLUSIONS: O-arm use is associated with a reduced rate of occipital plate dislodgment and has a similar complication incidence compared with C-arm-assisted surgery and does not prolong operative time despite the time needed for setting and scanning. Accordingly, an O-arm is safe and useful for occipitocervical fixation surgery.

Intraoperative assessment of hindfoot alignment using C-arm fluoroscopy.

BACKGROUND: Hindfoot malalignment can cause various foot and ankle problems. For better surgical performance and correction of hindfoot malalignments, reliable intraoperative determination of hindfoot alignment is essential. However, there is no standard method for the intraoperative assessment of hindfoot alignment. We devised an intraoperative modified Méary posteroanterior (IOPPA) view to assess intraoperative hindfoot alignment. This study aimed to compare this intraoperative method with other radiographic hindfoot alignment measurements. METHODS: Thirty-seven patients (47 feet) with various foot and ankle conditions scheduled to undergo surgery were prospectively recruited. Before surgery, the Saltzman, long axial, and modified Méary views were taken in a controlled and standardized fashion. IOPPA views were obtained under simulated weight bearing conditions using C-arm fluoroscopy in the operating room before surgery. The relationship between the IOPPA view and the three radiographic hindfoot alignments was evaluated using Pearson's correlation. RESULTS: The mean hindfoot alignment angle was varus 3.50° (CI, varus 1.91 to 5.08) on the Saltzman view, varus 2.00° (CI, varus 0.60 to 3.39) on the long axial view, varus 0.13° (CI, valgus 1.41 to varus 1.67) on the modified Méary view, and varus 1.32° (CI, valgus 0.02 to varus 2.65) on IOPPA view. The IOPPA view and the three other hindfoot alignment views were found to be significantly correlated (r = 0.60 for the Saltzman view, r = 0.50 for the long axial view, r = 0.71 for the modified Méary view, P < .05). The intraobserver ICC (Intraclass Correlation Coefficient) value was 0.974 and interobserver ICC (Intraclass Correlation Coefficient) value was 0.988 for the IOPPA view (P < .001). CONCLUSION: There was a statistically significant correlation between the IOPPA view and the other three hindfoot alignment views. We also found that interobserver and intraobserver ICC values were excellent. This study proposes that the IOPPA view can be used as a reliable intraoperative assessment tool for hindfoot alignment. LEVEL OF EVIDENCE: Prospective study.

Implementation and evaluation of the AAPM TG 111 for radiation dosimetry in a state-of-the-art C-arm cone beam CT system.

The aim of this study was to assess the dosimetric characteristics of a state-of-the-art C-arm cone beam computed tomography (CBCT) system using the methodology proposed by the American Association of Physicists in Medicine (AAPM) Task Group (TG) 111. The dose measurement methodology described in AAPM TG 111 for wide cone beam acquisitions without table translation was employed to estimate equilibrium beam length (αeq‾) and equilibrium dose (feq‾) in various interventional task-specific protocols with different tube arc projection geometries. Dose profiles were derived from point dose measurements in the centre and peripheral locations of the ICRU/AAPM and standard polymethyl methacrylate (PMMA) body phantom. Dose measurements were performed in phantom and free-in-air using a solid-state point detector. Monte Carlo (MC) based simulation dosimetry was performed to quantify the inhomogeneous dose patterns imparted in the phantoms. Estimatedαeq‾andfeq‾on the ICRU/AAPM phantom was up to 49.4 cm and 6.17 mGy/100 mAs, respectively. Corresponding values determined on the PMMA phantom were 139 cm and 8.8 mGy/100 mAs, respectively. Free-in-air dose measurement ranged from 1.43 mGy/100 mAs to 5.93 mGy/100 mAs. Per cent difference inαeq‾andfeq‾between MC simulation and solid-state point detector measurement methods in the ICRU/AAPM phantom were within 16% and 18%, respectively. Manufacturers can use the presented methodology to characterize the dosimetric properties of C-arm CBCT systems. Clinical medical physicists may follow this methodology to verify corresponding data provided by the manufacturer and check for C-arm CBCT system performance dosimetric consistency.

VDVM: An automatic vertebrae detection and vertebral segment matching framework for C-arm X-ray image identification.

BACKGROUND: C-arm fluoroscopy, as an effective diagnosis and treatment method for spine surgery, can help doctors perform surgery procedures more precisely. In clinical surgery, the surgeon often determines the specific surgical location by comparing C-arm X-ray images with digital radiography (DR) images. However, this heavily relies on the doctor's experience. OBJECTIVE: In this study, we design a framework for automatic vertebrae detection as well as vertebral segment matching (VDVM) for the identification of vertebrae in C-arm X-ray images. METHODS: The proposed VDVM framework is mainly divided into two parts: vertebra detection and vertebra matching. In the first part, a data preprocessing method is used to improve the image quality of C-arm X-ray images and DR images. The YOLOv3 model is then used to detect the vertebrae, and the vertebral regions are extracted based on their position. In the second part, the Mobile-Unet model is first used to segment the vertebrae contour of the C-arm X-ray image and DR image based on vertebral regions respectively. The inclination angle of the contour is then calculated using the minimum bounding rectangle and corrected accordingly. Finally, a multi-vertebra strategy is applied to measure the visual information fidelity for the vertebral region, and the vertebrae are matched based on the measured results. RESULTS: We use 382 C-arm X-ray images and 203 full length X-ray images to train the vertebra detection model, and achieve a mAP of 0.87 in the test dataset of 31 C-arm X-ray images and 0.96 in the test dataset of 31 lumbar DR images. Finally, we achieve a vertebral segment matching accuracy of 0.733 on 31 C-arm X-ray images. CONCLUSIONS: A VDVM framework is proposed, which performs well for the detection of vertebrae and achieves good results in vertebral segment matching.

A C-Arm-Free Minimally Invasive Technique for Spinal Surgery: Cervical and Thoracic Spine.

Background and Objectives: C-arm-free MIS techniques can offer significantly reduced rates of postoperative complications such as inadequate decompression, blood loss, and instrumentation misplacement. Another advantageous long-term aspect is the notably diminished exposure to radiation, which is known to cause malignant changes. This study emphasizes that, in some cases of spinal conditions that require a procedural intervention, C-arm-free MIS techniques hold stronger indications than open surgeries guided by image intensifiers. Materials and Methods: This study includes a retrospective analysis and review of various cervical and thoracic spinal procedures, performed in our hospital, applying C-arm-free techniques. The course of this study explains the basic steps of the procedures and demonstrates postoperative and intraoperative results. For anterior cervical surgery, we performed OPLL resection, while for posterior cervical surgery, we performed posterior fossa decompression for Chiari malformation, minimally invasive cervical pedicle screw fixation (MICEPS), and modified Goel technique with C1 lateral mass screw for atlantoaxial subluxation. Regarding the thoracic spine, we performed anterior correction for Lenke type 5 scoliosis and transdiscal screw fixation for diffuse idiopathic skeletal hyperostosis fractures. Results: C-arm-free techniques are safe procedures that provide precise and high-quality postoperative results by offering sufficient spine alignment and adequate decompression depending on the case. Navigation can offer significant assistance in the absence of normal anatomical landmarks, yet the surgeon should always appraise the quality of the information received from the software. Conclusions: Navigated C-arm-free techniques are safe and precise procedures implemented in the treatment of surgically demanding conditions. They can significantly increase accuracy while decreasing operative time. They represent the advancement in the field of spine surgery and are hailed as the future of the same.

Our C-Arm-Free Minimally Invasive Technique for Spinal Surgery: The Thoracolumbar and Lumbar Spine-Based on Our Experiences.

Background and Objectives: The implementation of intraoperative imaging in the procedures performed under the guidance of the same finds its history dating back to the early 1990s. This practice was abandoned due to many deficits and practicality. Later, fluoroscopy-dependent techniques were developed and have been used even in the present time, albeit with several disadvantages. With the recent advancement of several complex surgical techniques, which demand higher accuracy and are in conjunction with the existence of radiation exposure hazard, C-arm-free techniques were introduced. In this review study, we aim to demonstrate the various types of these techniques performed in our hospital. Materials and Methods: We have retrospectively analyzed and collected imaging data of C-arm-free, minimally invasive techniques performed in our hospital. The basic steps of the procedures are described, following with a discussion, along with the literature of findings, enlisting the merits and demerits. Results: MIS techniques of the thoracolumbar and lumbar spine that do not require the use of the C-arm can offer excellent results with high precision. However, several disadvantages may prevail in certain circumstances such as the navigation accuracy problem where in the possibility of perioperative complications comes a high morbidity rate. Conclusions: The accustomedness of performing these techniques requires a steep learning curve. The increase in accuracy and the decrease in radiation exposure in complex spinal surgery can overcome the burden hazards and can prove to be cost-effective.

Comparison of C-Arm-Free Oblique Lumbar Interbody Fusion L5-S1 (OLIF51) with Transforaminal Lumbar Interbody Fusion L5-S1 (TLIF51) for Adult Spinal Deformity.

Background and Objectives: Adult spinal deformity (ASD) surgery, L5-S1 lordosis is very important factor. The main objective of the research is to retrospectively compare symptomatic presentation and radiological presentation in the sequelae of oblique lumbar inter-body spinal fusion at L5-S1 (OLIF51) and transforaminal lumbar interbody fusion (TLIF) for ASD. Materials and Methods: We retrospectively evaluated 54 patients who underwent corrective spinal fusion for ASD between October 2019 and January 2021. Thirteen patients underwent OLIF51 (average 74.6 years old, group O) and 41 patients underwent TLIF51 (average 70.5 years old, group T). Mean follow-up period was 23.9 months for group O and 28.9 months for group T, ranging from 12 to 43 months. Clinical and radiographic outcomes are assessed using values including visual analogue scale (VAS) for back pain and Oswestry disability index (ODI). Radiographic evaluation was also collected preoperatively and at 6, 12, and 24 months postoperatively. Results: Surgical time in group O was less than that in group T (356 min vs. 492 min, p = 0.003). However, intraoperative blood loss of both groups were not significantly different (1016 mL vs. 1252 mL, p = 0.274). Changes in VAS and ODI were similar in both groups. L5-S1 angle gain and L5-S1 height gain in group O were significantly better than those of group T (9.4° vs. 1.6°, p = 0.0001, 4.2 mm vs. 0.8 mm, p = 0.0002). Conclusions: Clinical outcomes were not significantly different in both groups, but surgical time in OLIF51 was significantly less than that in TLIF51. The radiographic outcomes showed that OLIF51 created more L5-S1 lordosis and L5-S1 disc height compared with TLIF 51.

Outcomes of C-arm cone-beam CT-guided percutaneous procedures for thoracolumbar spondylodiscitis: a comparison between with and without intradiscal drainage.

INTRODUCTION: Percutaneous intradiscal drainage had little established evidence to date. We assessed the outcomes of C-arm cone-beam CT-guided (CBCT-guided) procedures for spondylodiscitis and compare procedures with and without intradiscal drainage. MATERIAL AND METHODS: A retrospective review was conducted on patients who underwent CBCT-guided procedures for spondylodiscitis with fluid collection in the intradiscal space between January 2010 and September 2021. Included patients were divided into two groups: with and without 'intradiscal drainage' (ID and non-ID, respectively). RESULTS: A total of 87 patients with thoracolumbar discitis (mean age 73.4 ± 12.3 years, 35 females) were included. There was no significant difference in clinical outcomes between groups. Although insignificant, a subgroup analysis of patients with discitis and psoas abscess showed a higher infection control success rate (81% (17/21) vs 58% (7/12), p = .23) and faster median C-reactive protein improvement (CRP <3 mg/dL: 12 vs 42 days, p = .11, CRP <1 mg/dL: 27 vs 45 days, p = .097) of ID than of non-ID. CONCLUSIONS: Findings did not clarify the role of intradiscal drainage when it was indicated in all cases of spondylodiscitis with fluid collection. Future studies with larger sample sizes of selected discitis cases are expected to demonstrate the superiority of intradiscal drainage.

Organ doses and normalized organ doses for various age groups in ultralow dose pediatric C-arm cone-beam CT.

OBJECTIVES: To estimate organ dose to major radiosensitive organs during pediatric body C-arm CBCT and determine normalized organ doses using a state-of-the-art equipment. METHODS: This is a study performed utilizing physical anthropomorphic phantoms. Four anthropomorphic phantoms that simulate the average individual as a neonate, 1-year-old, 5-year-old, and 10-year-old child were used. Personalized Monte Carlo (MC)-based dosimetry was performed to estimate organ doses in children referred to thorax and abdomen C-arm CBCT acquisitions on a recently released latest generation C-arm CBCT system. Age-specific normalized organ doses were generated and organ dose was estimated for skin, bone, breast, lungs, esophagus, thymus, and heart, in the thorax, and liver, adrenals, kidneys, pancreas, stomach, gall bladder, and spleen in the abdomen. Estimated doses were compared to corresponding values obtained with physical measurements performed using thermoluminescent dosimeters (TLD). RESULTS: The results consist of organ doses for thorax and abdomen acquisition protocols. The majority of organs received a dose below 1 mSv. For all ages, the normalized organ doses decreased from neonate to 10-year-old. The difference between the organ doses obtained with MC and TLDs was less than 8%. CONCLUSIONS: Normalized organ doses in pediatric C-arm CBCT varied with age. Pediatric C-arm CBCT with latest-generation systems may be performed with sub mGy dose for most organs. KEY POINTS: • The dose to the majority of organs from pediatric C-arm CBCT is in the sub mSv level. • The normalized organ doses decreased from neonate to 10-year-old. • Reported normalized organ doses may be used to estimate organ dose in pediatric C-arm cone-beam CT on modern equipment.

Staff dose evaluation by application of radiation protection during endoscopic retrograde cholangiopancreatography (ERCP) procedures performed with a mobile C-arm.

BACKGROUND: The radiation dose to staff performing endoscopic retrograde cholangiopancreatography (ERCP) is not negligible. PURPOSE: To evaluate the shielding effect of a table-suspended lower-body radiation shield for the positions in the room occupied by the operator, assisting nurse, and anesthesiologist, used during ERCP procedures with a mobile C-arm. MATERIAL AND METHODS: Eye lens dose, whole body dose, and extremity dose were measured with and without a table-suspended lower-body radiation shield in a phantom model and in clinical routine work. The effect of the shield was evaluated for each scenario and compared, and a projection was made for when shielding should be required from a regulatory point of view. RESULTS: In the phantom measurements, the shield provided significant shielding effects on the body and lower extremities for the operator but no significant shielding of the eye lens. The shielding effect for the assisting nurse was limited to the lower extremity. The clinical measurements yielded the same general result as the phantom measurements, with the major difference that the shield provided no significant reduction in the whole-body dose to the operator. CONCLUSION: The table-suspended shield has a significant shielding effect for the lower extremities of the operator and assisting nurse. For annual dose-area product values >300,000 cGycm2, the protection of the operator should be reinforced with a ceiling-suspended shield to avoid doses to the eye lens and body in excess of regulatory dose restrictions.

Investigation of radiation dose around C-arm fluoroscopy and relevant cancer risk to operating room staff.

This study aimed to evaluate the ambient dose equivalent around a C-arm device during spinal surgeries and determine the optimum locations for the surgeon and staff to keep radiation exposure as low as reasonably achievable. Furthermore, cancer risk incidence was estimated using the excess relative risk (ERR) concept of the biologic effects of ionizing radiation VII report for operating room (OR) staff. A lateral projection of the C-arm setup was considered in the current study. The ambient dose equivalent rate was measured using an electronic dosimeter in 30° steps all around for 1, and 1.6-m heights as well as 1, and 2-m distances away from a water tank (scattering medium). By assuming a typical workload, the annual ambient dose and a maximum number of permissible operations were determined. For a worst-case scenario, the dose was used to estimate the ERR for various organs including prostate, ovary, breast, lung, thyroid, and colon for attained ages of 35, 40, and 50 years. The maximum ambient dose equivalent rate was seen at 330° and 30° (about 600 µSv/h at 1 m height and a distance of 1 m from the scattering medium). The corresponding permissible workload for an OR staff was about 30,660 operations. Based on the obtained results, 60° next to the image intensifier was the optimum position for the surgeon, while 30° next to the tube was the worst position because of backscattered radiation. The ERR results showed that the lung and colon have the highest cancer risk incidence among the considered organs for both males and females, respectively.

Real-time three-dimensional fluoroscopy-navigated percutaneous pelvic screw placement for fragility fractures of the pelvis in the hybrid operating room.

BACKGROUND: The prognosis of conservative treatment for fragility fracture of the pelvis (FFP) in the older patients remains poor. Percutaneous pelvic screw placement (PPSP), which aids in the treatment of FFP, can be challenging to perform using fluoroscopy alone because of the proximity of blood vessels and neuroforamina. Hence, this study aimed to investigate the accuracy and clinical outcomes of PPSP using real-time 3D fluoroscopic navigation for FFP in the hybrid operating room. METHODS: This study included 41 patients with FFP who underwent PPSP in a hybrid operating room between April 2016 and December 2020. Intraoperative C-arm cone-beam CT was performed under general anesthesia. Guidewire trajectory was planned using a needle guidance system. The guidewire was inserted along the overlaid trajectory using 3D fluoroscopic navigation, and a 6.5 mm cannulated cancellous screw (CCS) was placed. The clinical outcomes and accuracy of the screw placement were then investigated. RESULTS: A total of 121 screws were placed. The mean operative time was 84 ± 38.7 minutes, and the mean blood loss was 7.6 ± 3.8 g. The mean time to wheelchair transfer was 2 days postoperatively. Pain was relieved in 35 patients. Gait ability from preoperative and latest follow-up after surgery was maintained in 30 (73%) patients. All 41 patients achieved bone union. Of the 121 screws, 119 were grade 0 with no misplacement; only 2 patients had grade 1 perforations. CONCLUSION: PPSP using real-time 3D fluoroscopic navigation in a hybrid operating room was accurate and useful for early mobilization and pain relief among older patients with FFP with an already-installed needle biopsy application.

Posterolateral Floating Technique for the Thoracic Ossification of the Posterior Longitudinal Ligament with Navigation: A Technical Note.

We describe a floating technique via a posterolateral approach with intraoperative O-arm navigation to facilitate decompression of the spinal cord in thoracic myelopathy due to severe ossification of the posterior longitudinal ligament (OPLL). A 62-year-old man with myelopathy due to thoracic OPLL had left-leg muscle weakness, urinary disturbance, and spastic gait. Bilateral leg pain and gait disturbance had persisted for 2 years. He was successfully treated by the posterolateral OPLL floating procedure and posterior pedicle fixation under O-arm navigation. At a 2-year follow-up, manual muscle testing results and sensory function of the left leg had recovered fully. His cervical Japanese Orthopedic Association score had improved from 5/12 to 11/12. The novel intraoperative O-arm navigation-guided posterolateral floating procedure for thoracic OPLL is effective for achieving precise decompression and strong fixation with a posterior approach only and can provide an excellent result for severe thoracic OPLL without the risk of adverse events from intraoperative radiation.