SA Journal of Radiology最新文献

Background: Magnetic resonance imaging (MRI) is used for the evaluation of degenerative spinal disease. However, its utility is restricted in routine practice because of contraindications and a lack of widespread availability. Dual-energy computed tomography (DECT) is a newer technique for the evaluation of degenerative spinal disease.

Objectives: This study aimed to evaluate the diagnostic performance of DECT with electron-density (ED) image reconstruction compared to standard CT for the detection of lumbar disc herniation, with MRI as the gold standard.

Method: The retrospective study included 84 patients between 01 July 2023 to 31 December 2023 who underwent DECT and 1.5-T MRI within 1 week. Four radiologists, blinded to the clinical and MRI information, independently evaluated the standard CT series and DECT series with ED reconstructions for lumbar disc herniation and spinal nerve root impingement. The gold standard for comparison was lumbar spine MRI, and diagnostic accuracy was measured with sensitivity and specificity.

Results: MRI revealed 417 lumbar disc herniations. Dual-energy computed tomography with ED reconstruction showed higher sensitivity (86.36% [532/616] vs. 57.79% [356/616]) and specificity (96.86% [1019/1052] vs. 95.82% [1008/1052]) for the detection of lumbar disc herniation compared to standard CT.

Conclusion: Dual-energy computed tomography with ED reconstruction shows better diagnostic performance for the detection of lumbar disc herniation compared to standard CT and can be a useful alternative imaging modality when MRI is contraindicated or unavailable.

Contribution: This study shows the usefulness of DECT as an alternative imaging technique for screening of degenerative spinal disease whenever MRI is contraindicated or unavailable.

Background: Studies have found that, at presentation, human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) has a less advanced primary tumour, more advanced lymph node spread and commonly has cystic metastatic lymph nodes in comparison to HPV-negative OPSCC.

Objectives: To compare the radiological features of HPV-positive and HPV-negative OPSCC in South African patients.

Method: A retrospective cross-sectional study was conducted at a large South African hospital. Eligibility required a histologically proven OPSCC between 2007 and 2023; a p16 antigen test and, if positive, a confirmatory HPV DNA PCR test and a baseline pre-treatment contrast enhanced neck CT scan. All eligible HPV-positive OPSCC patients and a random sample of eligible HPV-negative OPSCC patients were enrolled.

Results: Twenty-one HPV-positive and 55 HPV-negative OPSCC patients were recruited. There was no statistically significant difference in the tumour epicentre location, local advancement (≥ T3 in 67% and 71%, respectively, p = 0.54), mean primary tumour size (41 mm vs. 39 mm, p = 0.73), lymph node spread (bilateral or more in 67% vs. 82%, p = 0.22) or morphologically cystic lymph nodes (10% and 4%, p = 0.61).

Conclusion: There was no statistically significant difference in the CT imaging appearances of HPV-positive and HPV-negative OPSCC in the studied sample of South African patients.

Contribution: This study documents the radiological features of OPSCC in a small South African sample population, where HPV-positive and HPV-negative OPSCC could not be distinguished on CT criteria and did not display the classic features described in the literature.

Background: In CT, the volumetric CT dose index (CTDI_vol), dose-length product (DLP) and patient's size-specific dose estimates (SSDE) are used as diagnostic reference level (DRL) metrics.

Objectives: To develop clinical local DRL values for CT chest-abdomen-pelvis (CAP) examinations using the CTDI_vol, DLP and SSDE, and to determine the image quality achieved.

Method: In total, 201 cancer patients were included in the study. The scanning parameters, dose metrics from the CT unit and participants' body mass index (BMI) were documented. The local CT DRL values for CAP examinations were defined as the median and 75th percentiles of the dose distribution.

Results: The local DRL values given in terms of median CTDI_vol ranged between 8.4 mGy and 12.7 mGy for the different types of cancers. The median DLPs ranged from 848 to 1173.4 mGy.cm for the various cancers. Generally, the radiation dose was directly proportional to the BMI and number of scan phases. Significant differences were observed between the DRLs for the various size-related parameters, number of scan phases and BMI classifications. The image quality was clinically satisfactory.

Conclusion: No baseline data for clinical DRL values were available for this medical oncology department. The achieved DRLs were similar to published size-specific DRLs. The image quality was maintained during CT imaging. Dose optimisation and image quality assessment should be implemented to ensure optimal scanning parameters for different cancers in CT CAP examinations.

Contribution: The first size-specific local DRL values for CT CAP investigations carried out on oncology patients in South Africa have been established.

Phosphaturic mesenchymal tumours (PMT) are rare, benign lesions and the most common tumour to cause tumour-induced osteomalacia (TIO), a paraneoplastic syndrome. Patients frequently exhibit severe osteomalacia, accompanied by multiple fractures, which significantly impair their quality of life. Complete surgical resection is curative.

Contribution: A rare case of sinonasal PMT is presented, with a focus on the imaging findings and role of the radiologist and nuclear physician.

Disorders related to defaecation are widely common in the population and are often overlooked. Patients may present with a wide variety of symptoms such as constipation, faecal incontinence, painful defaecation, incomplete defaecation, hard stools, rectal bleeding, and mass per rectum. Complete clinical examination with radiological imaging, using dynamic MR Defaecography, can help in assessing, grading, and managing posterior compartment pelvic floor disorders and complex dysfunctions. The cases reveal a spectrum of pelvic floor disorders and complex dysfunctions including spastic pelvic floor syndrome, Grade 3 anorectal descent with rectocoele and cystocoele, tri-compartmental descent with obstructed defaecation syndrome, complete external rectal prolapse with Grade 3 abnormal anorectal descent and rectal intussusception.

Contribution: This case series emphasises the importance of understanding the correlation of clinical and radiological imaging findings in posterior compartment pelvic floor dysfunctions through a series of cases presenting with clinical complaints related to defaecation.

Background: The radiology report is the primary means of conveying imaging findings between radiologists and clinicians. As a result, clinician satisfaction with the radiology report is an indicator of its quality and clinical relevance. It is crucial to identify factors that can enhance the radiology report in order to improve service delivery.

Objectives: This study evaluates clinician and radiologist opinions, preferences and clinician utilisation of the radiology report.

Method: Mixed quantitative and qualitative survey questionnaires were distributed in-person and online from December 2022 to February 2023 to a total of 287 clinicians and 43 independent medical practitioners specialising in radiology.

Results: A total of 73.0% of radiologists and 56.5% of clinicians expressed satisfaction with the radiology reports. Additionally, 72.0% of radiologists expressed dissatisfaction with the history provided on the referral forms. It was found that 87.6% of clinicians read the radiology report, while 26.2% reviewed the radiological imaging without referring to it. Interestingly, 77.8% of clinicians preferred itemised listed reports, whereas 53.8% of radiologists preferred reports in paragraph format. It was discovered that 69.6% of radiologists and 65.4% of clinicians preferred a standardised reporting format.

Conclusion: More than half of the clinicians and most of the radiologists expressed satisfaction with the radiology report. Both clinicians and radiologists showed a preference for a structured reporting format. A crucial element in constructing a good radiology report was having a relevant clinical history. The radiologist continued to be the preferred professional for interpreting radiological imaging.

Contribution: This survey was a good starting point for improving communication between clinicians and radiologists. This will ultimately result in reports that are more useful to clinicians and radiologists who have a better understanding of what should be included in reports and how they should be structured.

Background: Breast cancer presents a significant global health burden. An accurate differentiation between benign and malignant lesions is imperative for timely intervention. While dynamic contrast enhanced MRI (DCE-MRI) is highly sensitive, its specificity is limited. This has led to the exploration of diffusion-weighted imaging (DWI) in distinguishing between benign and malignant breast lesions.

Objectives: The study aimed to explore the diagnostic utility of DWI in distinguishing between benign and malignant breast lesions.

Method: Assessment of 38 breast lesions using DWI with a b value of 800 s/mm², performed with 3 Tesla MRI. The diagnostic performance of two different region of Interest (ROI) placement approaches was compared to obtain a feasible cut-off value of apparent diffusion coefficient (ADC) to differentiate between malignant and benign lesions. The histopathological reports were used as the gold standard.

Results: ADC values of malignant lesions were significantly lower than those of benign lesions (0.84 × 10^-3 mm²/s vs. 1.54 × 10^-3 mm²/s). The average ADC measured using a small-sized 2D ROI including the darkest part in the ADC map, performed better than the large 2D ROI covering the entire lesion.

Conclusion: Using a cut-off value of 0.98 × 10^-3 mm²/s, ADC obtained high sensitivity (90%) and specificity (88.9%) in distinguishing between benign and malignant breast lesions.

Contribution: Utilising quantitative analysis of DWI with ADC value measurement, reliably distinguished between benign and malignant breast lesions in this cohort, especially when employing a higher b value of 800 s/mm².

Background: Timely detection of oesophageal injuries post-penetrating neck trauma is imperative because of the associated high morbidity and mortality. Patients commonly undergo both CT angiography (CTA) and contrast swallow studies (fluoroscopic oesophagography) when oesophageal injury is suspected.

Objectives: To determine the radiological findings of oesophageal injury after penetrating neck trauma comparing CTA and fluoroscopic oesophagography at a single tertiary centre.

Method: The study retrospectively reviewed the data from CTA and fluoroscopic oesophagography reports of patients suspected of oesophageal injuries secondary to penetrating neck trauma at a tertiary hospital in South Africa from January 2018 to December 2022.

Results: A total of 76 records were reviewed. The mean age for the participants was 31.5 years, ranging from 0.75-66 years. In this study 6/76 (8%) patients had confirmed oesophageal injury on fluoroscopy, which is considered the gold standard. The majority of penetrating neck injuries were in the 20-29 year age group, with 33/76 (43%) injuries. Stab wounds as the mechanism of injury accounted for 57/76 (75%). Dysphagia was experienced by 10/76 (13%) of those who had injuries. Zone I injuries accounted for 33/76 (43%) of the injuries.

Conclusion: The incidence of oesophageal injuries secondary to penetrating neck injuries is comparable to previous studies. This study determined that CTA has a high sensitivity but low specificity.

Contribution: Fluoroscopic oesophagography should, therefore, be performed in patients who have an abnormal CTA coupled with clinical signs and symptoms of oesophageal injury.

Background: Liver transplantation is the definitive management for patients with end-stage liver disease. Preoperative computed tomography (CT) is used in living donor liver transplant (LDLT) for donor and graft selection as well as predicting graft weight.

Objectives: The aim of this study is to establish the relationship between estimated graft volume (EGV) and actual graft weight (AGW) and ascertain a correlation coefficient that will improve the accuracy of EGV in a South African population.

Method: The study included 117 LDLT between March 2013 and August 2022. Of these, 86 were left lateral (LL), 15 right lobe (R), 10 left lobe with caudate (LC), five left lobe (L) and one segment two (monosegment) grafts. Estimated graft volume and actual graft weight were compared using the Pearson coefficient and the relationship was illustrated with scatter plots.

Results: Estimated graft volume and AGW had a strong positive correlation with a Pearson correlation (R) of 0.95 (p < 0.001). The relationship was significantly linear with a correlation coefficient of 0.71. The mean EGV was significantly higher than that of AGW (388 mL ± 249 mL vs. 353 g ± 184 g) with overestimation in 61% of cases. Left lateral and R grafts were the most prevalent LDLT graft type, both having a strong linear correlation between EGV and AGW.

Conclusion: Applying a correlation coefficient of 0.71 will improve the accuracy of CT volumetry graft weight predictions.

Contribution: A unique correlation coefficient will improve EGV accuracy, aiding in preoperative planning and mitigating post-operative complications in both donors and recipients.