An update on epidural steroid injections: is there still a role for particulate corticosteroids?

Epidural steroid injections (ESIs) play an important role in the multifaceted management of neck and back pain. Corticosteroid preparations used in ESIs may be considered "particulate" or "non-particulate" based on whether they form a crystalline suspension or a soluble clear solution, respectively. In the past two decades, there have been reports of rare but severe and permanent neurological complications as a result of ESI. These complications have principally occurred with particulate corticosteroid preparations when using a transforaminal injection technique at cervical or thoracic levels, and only rarely in the lumbosacral spine. As a result, some published clinical guidelines and recommendations have advised against the use of particulate corticosteroids for transforaminal ESI, and the FDA introduced a warning label for injectable corticosteroids regarding the risk of serious neurological adverse events. There is growing evidence that the efficacy of non-particulate corticosteroids for pain relief and functional improvement after ESI is non-inferior to particulate agents, and that non-particulate injections almost never result in permanent neurological injury. Despite this, particulate corticosteroids continue to be routinely used for transforaminal epidural injections. More consistent clinical guidelines and societal recommendations are required alongside increased awareness of the comparative efficacy of non-particulate agents among specialists who perform ESIs. The current role for particulate corticosteroids in ESIs should be limited to caudal and interlaminar approaches, or transforaminal injections in the lumbar spine only if initial non-particulate ESI resulted in a significant but short-lived improvement.

The role of radiology in addressing the challenge of lung cancer after lung transplantation.

The importance of lung cancer as a complication of lung transplantation is increasingly recognised. It may become an important survival-limiting factor in lung transplant patients as management of other complications continues to improve and utilisation of extended criteria donors grows. Radiology can play a key role in tackling this issue at multiple stages in the transplantation pathway and follow-up process. Routine chest CT as part of pre-transplant recipient assessment (and donor assessment if available) can identify suspicious lung lesions with high sensitivity and detect chronic structural lung diseases such as pulmonary fibrosis associated with an increased risk of malignancy post-transplant. Pre-transplant CT also provides a comparison for later CT studies in the assessment of nodules or masses. The potential role of regular chest CT for lung cancer screening after transplantation is less certain due to limited available evidence on its efficacy. Radiologists should be cognisant of how the causes of pulmonary nodules in lung transplant patients may differ from the general population, vary with time since transplantation and require specific recommendations for further investigation/follow-up as general guidelines are not applicable. As part of the multidisciplinary team, radiology is involved in an aggressive diagnostic and therapeutic management approach for nodular lung lesions after transplant both through follow-up imaging and image-guided tissue sampling. This review provides a comprehensive overview of available clinical data and evidence on lung cancer in lung transplant recipients, and in particular an assessment of the current and potential roles of pre- and post-transplant imaging. KEY POINTS: • Lung cancer after lung transplantation may become an increasingly important survival-limiting factor as mortality from other complications declines. • There are a number of important roles for radiology in tackling the issue which include pre-transplant CT and supporting an aggressive multidisciplinary management strategy where lung nodules are detected in transplant patients. • The introduction of routine surveillance chest CT after transplant in addition to standard clinical follow-up as a means of lung cancer screening should be considered.

Prevalence and clinical significance of incidental findings on CT attenuation correction for myocardial perfusion imaging.

BACKGROUND: The appropriate clinical approach to incidentally detected lesions (IDLs) on CT attenuation correction (CTAC) images in myocardial perfusion imaging (MPI) remains uncertain. We sought to establish their prevalence and clinical significance in a large cohort and compared to previous studies to help provide further clarity and guide future clinical practice. METHODS AND RESULTS: A total of 3758 MPI studies were reviewed retrospectively. IDLs of potential clinical significance-not known before MPI - were reported in 245 (6.5%) of these cases. Following appropriate further investigation/follow-up, these were of proven clinical significance in 30 (12.2%) cases with 14 patients (5.7%) harboring previously undiagnosed or progressive malignancies. The positive predictive value (PPV) for clinically significant incidental findings on CTAC images was 17.2% and the PPV value for incidental malignant findings was 8.0%. CONCLUSION: Although incidental findings on CTAC images in MPI are common and often clearly insignificant at time of MPI reporting, many are clinically significant with a relatively high positive predictive value. This is especially so for malignancies. Our findings, therefore, in combination with previous studies as described here support routine reporting and appropriate further investigation of incidental CTAC findings in MPI.

Multimodal imaging of composite carbon fiber-based implants for orthopedic spinal fixation.

OBJECTIVE: As cancer treatments continue to improve, the incidence of spinal metastases and the need for surgical management of these with fixation procedures are growing rapidly. Traditionally metallic implants, composed of titanium alloy, have been used in surgical fixation of unstable or symptomatic vertebral metastases or traumatic injuries. Metallic implants, however, cause significant artifact on post-operative imaging, degrading image quality and limiting interpretation, and can also impair the planning and delivery of radiotherapy. Composite carbon fiber-based materials, such as carbon fiber-reinforced polyetheretherketone (PEEK), have been developed to overcome these issues and are now available for spinal fixation procedures. We aimed to review the multimodal imaging features of these new implants. MATERIALS AND METHODS: Current literature and a case example from our institution were used to describe the multimodal imaging characteristics and considerations of new carbon fiber-based spinal fixation implants. RESULTS: New carbon fiber-based spinal implants allow far greater visualization of surrounding structures on post-operative cross-sectional imaging, significantly improving diagnostic accuracy and precision of radiotherapy planning, and do not significantly absorb or scatter X-ray photons during radiotherapy delivery. There are, however, important surgical and radiologic considerations associated with the use of carbon fiber-based implants which radiologists must be aware of, such as implications for surgical planning and intra-operative fluoroscopic and post-operative plain radiographic imaging. CONCLUSION: The use of carbon fiber-based implants, rather than traditional metallic implants, for spinal fixation offers significant advantages for post-operative diagnostic imaging and radiotherapy planning and delivery.

MR imaging of acute abdominal pain in pregnancy.

Abdominal pain in pregnancy is a diagnostic challenge with many potential aetiologies. Diagnostic imaging is a valuable tool in the assessment of these patients, with ultrasound commonly employed first line. MRI is an excellent problem-solving adjunct to ultrasound and has many advantages in terms of improved spatial resolution and soft tissue characterisation. This pictorial review aims to outline the role of MRI in the work up of acute abdominal pain in pregnancy and provide imaging examples of pathologies which may be encountered.

An abbreviated MRI protocol for surveillance of cystic pancreatic lesions.

PURPOSE: Cystic pancreatic lesions (CPLs) are common and increasingly encountered in clinical radiology practice. The appropriate imaging surveillance strategy for lower-risk CPLs (branch duct-intraductal papillary mucinous neoplasms and indeterminant small cystic lesions) has been a topic of intense study and debate in recent years. MRI is considered the investigation of choice for initial characterisation and follow-up of CPLs. Follow-up intervals for CPLs vary from 6 months to 2 years and surveillance may be lifelong or until the patient is no longer considered fit for potential surgical intervention. This creates a significant burden on MRI resources as a standard protocol pancreatic MRI may have an acquisition time of up to 35-50 min. However, the necessity of contrast-enhanced sequences and diffusion weighted imaging (DWI) for routine follow-up of CPLs has been questioned in recent years. METHODS: We reviewed the available evidence to determine whether an abbreviated MRI (A-MRI) protocol may be safely adopted for surveillance of CPLs, as has been implemented in other clinical scenarios. RESULTS: A number of recent retrospective studies have indicated that an A-MRI, omitting contrast-enhanced and DWI, may be used for CPL surveillance without any suspicious features or cases of malignancy being missed. Although small number of cases may need to be recalled for additional MR sequences based on the A-MRI findings, there is still a significant overall timesaving. CONCLUSION: The best available evidence currently suggests that an A-MRI protocol should be considered for routine surveillance of CPLs. Prospective studies are required to ensure the findings reported in these retrospective case studies are backed up in ongoing clinical practice.

Readability of patient education materials related to radiation safety: What are the implications for patient-centred radiology care?

BACKGROUND: Increasing numbers of patients and carers rely on online resources for healthcare information. Radiation safety can be misunderstood by patients and clinicians and lead to patient anxiety. We aimed to assess the readability of online patient educational materials (PEMs) related to radiation safety. METHODS: A total of 84 articles pertaining to radiation safety from 14 well-known online resources were identified. PEMs were then analysed using Readability Studio Professional Edition Version 2019. Readability was assessed using eight different instruments: the Flesch-Kincaid Reading Grade Level, Raygor Estimate, SMOG, Coleman-Liau, Fry, FORCAST, Gunning Fog, and Flesch Reading Ease Score formula. The mean reading grade level (RGL) of each article was compared to the 6th and 8th grade reading level using 1-sample t-tests. RESULTS: The cumulative mean RGL for all 84 articles was 13.3 (range = 8.6-17.4), and none were written at or below the 6th or 8th grade level. The cumulative mean RGL exceeded the 6th grade reading level by an average of 7.3 levels (95% CI, 6.8-7.8; p < 0.001) and the 8th grade level by an average of 5.3 grade levels (95% CI, 4.8-5.8; p < 0.001). The mean Flesch Reading Ease Score was 39/100 ('difficult'). CONCLUSION: Currently available online PEMs related to radiation safety are still written at higher than recommended reading levels. Radiation safety is a topic in which the specialist training of radiologists is crucial in providing guidance to patients. Addressing the readability of online PEMs can improve radiology-patient communication and support the shift to a patient-centred model of practice.

Incidental cardiac uptake in bone scintigraphy: increased importance and association with cardiac amyloidosis.

Extraosseous radiotracer uptake during bone scintigraphy must be carefully assessed and it offers the potential to detect previously undiagnosed disease processes. A range of neoplastic, metabolic, traumatic, ischaemic and inflammatory disorders can cause soft tissue accumulation of bone avid radiopharmaceuticals. Accordingly, cardiac uptake in bone scintigraphy has a broad differential diagnosis and is commonly attributed to ischaemia/infarction related to coronary artery disease. However, there has been renewed focus on incidental cardiac uptake in recent years in light of significant developments in the diagnosis and management of cardiac amyloidosis.

The needle and the damage done: musculoskeletal and vascular complications associated with injected drug use.

Injected drug use is associated with a wide range of medical complications which are predominantly musculoskeletal and vascular in nature. Illicit drug use is increasing worldwide. Patients with complications of injected drug use often present in a non-specific manner without a reliable clinical history. Musculoskeletal complications are typically infective in aetiology and may vary widely in severity from mild to life-threatening. A multimodal imaging approach is often required for both diagnostic imaging and image-guided sampling. Plain radiographs are often an important initial test, for example in identifying retained needles from injection. Ultrasound and CT play important roles in the assessment of complex soft tissue complications and MRI is the imaging modality of choice for bone and joint disorders. Vascular complications may be venous or arterial in nature and usually occur locally at the injection site. These complications may be related to direct injury to the vessel wall by a needle, or secondary to local infection and inflammation. A multimodal imaging strategy is also often required in the assessment of these vascular complications, typically involving a combination of ultrasound and CT. Familiarity with the multimodal imaging features of the complications related to injected drug use is crucially important as they may be rapidly progressive and life-threatening and require timely diagnosis.

The importance of appropriate reporting and investigation of incidental findings on computed tomography attenuation correction images during myocardial perfusion scintigraphy.

We present a case of lung cancer incidentally detected as a pulmonary nodule on computed tomography attenuation correction (CTAC) images during myocardial perfusion scintigraphy (MPS). Unfortunately, the incidental lesion was not fully investigated following MPS report and had developed into metastatic lung carcinoma when diagnosed over 1 year later, with failure of subsequent emergent chemotherapy. The disease appeared to be localized when initially detected during MPS. This case highlights the importance and potential clinical value of routine review of CTAC images in MPS with appropriate reporting and further investigation of suspicious incidental findings. In addition, the importance of effective communication between nuclear medicine department and treating team is clear to ensure suspicious incidental findings are given sufficient credence and thoroughly investigated promptly to avoid adverse clinical outcomes.

Abdominal viscus penetration by laparoscopic-adjustable gastric band tubing: case report and review.

Laparoscopic-adjustable gastric band (LAGB) complications are increasingly recognised as follow-up time increases. These are most commonly related to the gastric band or port site, but complications of the connecting tubing are also reported. We present a case of LAGB tubing penetration through the transverse colon causing abdominal sepsis in a complex surgical abdomen and review prior published cases of abdominal viscus penetration by LAGB tubing. Like complications involving all LAGB components, these often present with non-specific abdominal signs and symptoms and undergo abdominal CT as an early investigation. This makes knowledge of normal and pathological imaging features of LAGB components important in radiology practice.