"Scout No Scan" Technique Reduces Patient Radiation Exposure During CT-Guided Spine Biopsy

Localiser radiographs in CT: Current practice, radiation dose, image quality and clinical applications

INTRODUCTION

Survey or localiser radiographs are integral to CT imaging. However, the diverse functions and roles of the localiser radiograph are often obscure to radiographers and radiologists. This scoping review reports the full scope of localiser radiograph use and function in contemporary CT imaging.

METHODS

A scoping review was performed. A systematic literature search was conducted using four databases: MEDLINE, CINAHL, Emcare and Scopus from January 2013 to December 2023. Data extraction was conducted by two review authors and validated by a third reviewer. Thirty-six studies were included in this review.

RESULTS

Three major themes emerged: radiation dose management, image quality considerations and clinical protocol applications. Specifically, the number, order of selection and directions of localiser radiographs significantly impact patient dose and image quality; which are additionally impacted by off-centre patient positioning, which can influence the accuracy of body size estimates and CT numbers. Finally, the optimal selection of localiser radiographs, including exposure parameters (kVp, mAs), can be a part of clinical task-based imaging protocol optimisation.

CONCLUSIONS

The utilities of localiser radiographs in CT imaging are varied. It is salient that radiographers and radiologists understand their role and the impacts of poor application to ensure that radiation dose is minimised and image quality maximised through correct use. Radiographers and radiologists should also be aware of the impact of poor patient positioning on ACTM function, dose and image quality. Additionally, localiser radiographs should be used for clinical task-based protocol optimisation.

IMPLICATIONS FOR PRACTICE

The number, order of selection, direction, patient off-centring, and exposure parameters must be considered when utilising localiser radiographs as they impact dose, image quality, and protocol applications. It is essential for radiographers and radiologists to understand these impacts.

Computed tomography-guided transforaminal lumbar puncture using local anesthesia and a straight 22-gauge spinal needle for intrathecal nusinersen in adults: Findings in 77 procedures

BACKGROUND

Intrathecal nusinersen is the first Food and Drug Administration-approved treatment for spinal muscular atrophy. Reliable intrathecal access is critical for initial and maintenance therapy; however, this can be challenging in older patients with spinal muscular atrophy many of whom have had prior lumbar instrumentation and osseous fusion. Transforaminal lumbar punctures have emerged as a technique for intrathecal access that avoids the hazards of cervical punctures. We describe our technique for transforaminal lumbar punctures under computed tomography guidance using local anesthesia and a straight 22-gauge needle.

METHODS

Following local institutional review board approval, medical records of all patients undergoing computed tomography-guided transforaminal lumbar puncture for intrathecal nusinersen injection were obtained and analyzed. The rate of technical success and immediate complications were recorded. Any delayed complications noted in a 3-day follow-up phone call and future office visit were also recorded. Data collation and analysis were performed using Excel.

RESULTS

A total of 77 transforaminal lumbar punctures were performed with intrathecal administration of nusinersen, for a 100% technical success rate. Local anesthesia was used in 76 cases, with conscious sedation used in one case. General anesthesia was not used in any case. There were no major complications. One patient had a postdural puncture headache that resolved completely after a transforaminal epidural blood patch performed 4 days later.

CONCLUSIONS

Intrathecal administration of nusinersen is critical for treatment of patients with spinal muscular atrophy. Our described technique allows for reliable access to the intrathecal space using local anesthesia and a straight 22-gauge spinal needle under computed tomography guidance, and is easily reproducible.

Review article: the current status of CT-guided needle biopsy of the spine

CT-guided percutaneous needle biopsy of the spine is a well-described technique for determining the nature of indeterminate vertebral lesions or establishing a diagnosis of spinal infection, the high diagnostic accuracy and the safety of the procedure having been extensively documented. The purpose of the current article is to review the literature to date on CT-guided spinal biopsy. Specifically, indications for spinal biopsy, techniques for optimising yield, detail of the approaches for various spinal levels which is dependent upon both the region within the spinal column and lesion location within the vertebra (body vs. neural arch), determinants of biopsy outcome and complications are covered. It is hoped that the review will be of particular benefit to junior radiologists who are required to perform this procedure.

Image-guided botulinum toxin injection in the lateral abdominal wall prior to abdominal wall reconstruction surgery: review of techniques and results

Ventral hernias represent the most common complication after abdominal surgery. Loss of domain and/or large ventral hernias in patients are especially challenging for surgeons to manage, but preoperative image-guided botulinum toxin injection has emerged as an effective adjunct to abdominal wall surgery. Loss of domain is caused by chronic muscle retraction of the lateral abdominal wall and leads to an irreducible protrusion of abdominal viscera into the hernia sac. Botulinum toxin can be used in the oblique muscles as a chemical component relaxation technique to aid abdominal wall reconstruction. Intramuscular botulinum toxin injection causes functional denervation by blocking neurotransmitter acetylcholine release resulting in flaccid paralysis and elongation of lateral abdominal wall muscles, increasing the rate of fascial closure during abdominal wall reconstruction, and decreasing recurrence rates. In total, 200-300 units of onabotulinumtoxinA (Botox®) or 500 units of abobotulinumtoxinA (Dypsort®) in a 2:1 dilution with normal saline is most commonly used. Botulinum toxin can be injected with ultrasonographic, EMG, or CT guidance. Injection should be performed at least 2 weeks prior to abdominal wall reconstruction, for maximal effect during surgery. At minimum, botulinum toxin should be injected into the external and internal oblique muscles at three separate sites bilaterally for a total of six injections. Although botulinum toxin use for abdominal wall reconstruction is currently not indicated by the Food and Drug Administration, it is safe with only minor complications reported in literature.

Computed Tomography-Guided Vertebral Biopsy in Suspected Tuberculous Spondylodiscitis: Comparing a New Navigational Tram-Track Technique versus Conventional Method

Introduction Computed tomography (CT)-guided vertebral biopsy is always recommended for histopathological and microbiological confirmation in cases of tuberculous spondylodiscitis and for antimycobacterial drug sensitivity testing.

Aim To compare the conventional technique and a novel axis-defined tram-track technique of CT-guided vertebral biopsy in suspected tuberculous spondylodiscitis.

Materials and Methods Sixty-seven patients of clinico-radiologically suspected tuberculous spondylodiscitis referred for CT-guided vertebral biopsy were categorized into two groups: “Group A” patients (n = 32) underwent biopsy by conventional technique, and “Group B” patients (n = 35) by axis-defined tram-track technique. The time taken for procedure, radiation exposure, and any procedural complications were recorded for both the groups.

Results A statistically significant difference in procedure time and mean radiation dose was observed between the two groups: a longer procedural time was required in “Group A” (52.5 ± 3.5 minutes) as compared to “Group B” (37.3 ± 3.6 minutes) (p < 0.0001); and mean radiation dose (CTDIvol) in “Group A” and “Group B” was 8.64 ± 1.06 mGy and 5.73 ± 0.71 mGy, respectively (p < 0.0001). However, the difference in complication rate and tissue yield for successful diagnosis of the biopsies in the two groups was found to be statistically insignificant.

Conclusion Axis-defined tram-track technique was found to have a significantly shorter procedural time as well as lower radiation exposure compared to the conventional technique of vertebral biopsy in our study.