Congenital cholesteatoma: what radiologists need to know.

Congenital cholesteatoma is a rare, non-neoplastic lesion that causes conductive hearing loss in children. It is underrecognized and often diagnosed only when there is an established hearing deficit. In the pediatric population, hearing deficiency is particularly detrimental because it can impede speech and language development and, in turn, the social and academic well-being of affected children. Delayed diagnosis leads to advanced disease that requires more extensive surgery and a greater chance of recurrence. A need to promote awareness and recognition of this condition has been advocated by clinicians and surgeons, but no comprehensive imaging review dedicated to this entity has been performed. This review aims to discuss the diagnostic utility of high-resolution computed tomography and magnetic resonance imaging in preoperative and postoperative settings in congenital cholesteatoma. Detailed emphasis is placed on the essential preoperative computed tomography findings that facilitate individualized surgical management and prognosis in the pediatric population.

Clinical and pathological characterization of FLNC-related myofibrillar myopathy caused by founder variant c.8129G>A in Hong Kong Chinese.

FLNC-related myofibrillar myopathy could manifest as autosomal dominant late-onset slowly progressive proximal muscle weakness; involvements of cardiac and/or respiratory functions are common. We describe 34 patients in nine families of FLNC-related myofibrillar myopathy in Hong Kong ethnic Chinese diagnosed over the last 12 years, in whom the same pathogenic variant c.8129G>A (p.Trp2710*) was detected. Twenty-six patients were symptomatic when diagnosed; four patients died of pneumonia and/or respiratory failure. Abnormal amorphous material or granulofilamentous masses were detected in half of the cases, with mitochondrial abnormalities noted in two-thirds. We also show by haplotype analysis the founder effect associated with this Hong Kong variant, which might have occurred 42 to 71 generations ago or around Tang and Song dynasties, and underlain a higher incidence of myofibrillar myopathy among Hong Kong Chinese. The late-onset nature and slowly progressive course of the highly penetrant condition could have significant impact on the family members, and an early diagnosis could benefit the whole family. Considering another neighboring founder variant in FLNC in German patients, we advocate development of specific therapies such as chaperone-based or antisense oligonucleotide strategies for this particular type of myopathy.

Imaging spectrum and complications of otogenic infections: insights into delayed diagnosis.

Skull base osteomyelitis (SBO) is a late manifestation of complicated otogenic infections that presents a diagnostic challenge. Delayed or missed diagnoses lead to high morbidity and mortality and can be attributed to non-specific symptoms, subtle early radiologic findings, radiologic mimicry of nasopharyngeal carcinoma (NPC), and under-recognition from clinician and radiologists. This pictorial review aims to emphasize on early imaging recognition and distinction between SBO and NPC.

Acute traumatic subtalar dislocation: A rare but important clinical entity with 15-year retrospective radiological analysis of 23 cases.

Objectives: The objectives of this study were to contribute to the limited existing knowledge about subtalar dislocations, analyze the computed tomography (CT) findings and advantages over radiography, and report the rate and potential risk factors of post-traumatic peri-talar osteoarthritis (OA). Material and Methods: A total of 23 cases of traumatic subtalar dislocation during a 15-year period at three regional hospitals were retrospectively reviewed. Results: All 23 cases were closed dislocations. Successful close reduction was performed in 17 patients (73.9%) and 6 patients (26.1%) required open reduction and internal fixation. Twenty patients (87%) had associated foot and ankle fractures. Fractures of calcaneal medial tubercle were the most common (75%), followed by talar head (30%), sinus tarsi (25%), and medial malleolus (25%). The radiograph's sensitivity for identifying fractures was 48.1%. The mean follow-up period is 30 months. Symptomatic OA affected 8 patients (36.4%). No post-trauatic talar avascular necrosis was noted. Fractures were present in all of those patients with post-traumatic OA (100%). Three out of five patients who sustained high-energy mechanism injury developed radiographic OA (66.7%). Three out of six patients (50%) treated with open reduction and internal fixation also developed radiographic OA. Conclusion: Subtalar dislocation remains a rare injury. It is strongly associated with foot and ankle fractures. Fractures of the calcaneal medial tubercle were the most common. The risk of post-traumatic symptomatic peritalar OA is high. CT is useful in detecting occult fractures and injured bony subregions. We postulated potential risk factors of post-traumatic OA (fracture, high-energy mechanism of injury, open reduction, and internal fixation); however, this requires further study.

Atlanto-occipital assimilation: A pictorial review of a commonly missed pathology.

Atlanto-occipital assimilation is a congenital craniovertebral junction malformation where the partial or complete fusion of the atlas and occiput occurs. Atlanto-occipital assimilation can be associated with numerous complications, including basilar invagination, atlantoaxial subluxation, Chiari malformation, congenital vertebral bodies fusion, and cord compression. As a result, vigilant identification and accurate reporting of atlanto-occipital assimilation are essential. The purpose of this review article is to discuss the numerous complications and associations of atlanto-occipital assimilation, such that an accurate diagnosis could be made for this commonly missed pathology.

Rapidly destructive hip osteoarthritis: a diagnosis not to miss.

This review illustrates the imaging features of rapidly destructive hip osteoarthritis (RDHO) across different imaging modalities. RDHO is a rare joint disease of unknown aetiology resulting in rapid deterioration of the hip joints. Patients often present with severe hip pain and can progress to complete joint destruction in 6 months to 3 years causing disability. Since its clinical and imaging features often overlap with other conditions, the diagnosis is easily missed in daily practice. The purpose of this paper is to outline the characteristic imaging features of RDHO, aiming to enhance awareness of this disease entity and promote timely treatment for patients. Sequential radiographs are particularly important in demonstrating the rapid progression of radiographic findings and with the early recognition of characteristic features, diagnosis can be made to avoid treatment delay. Although CT scan is not necessary for diagnosis, it is useful in evaluating the extent of joint destruction and guiding surgical planning. MRI can provide additional information and rule out other pathologies with similar symptoms. Overall, radiographs, CT and MRI are common modalities used in the evaluation of RDHO.

Should endovascular stenting be used routinely as first-line treatment for malignant superior vena cava syndrome?-a critical review in the context of recent advances in oncological treatments.

Malignant superior vena cava syndrome (SVCS) is no longer considered a medical emergency in most cases because it rarely leads to life-threatening complications. However, it results in disturbing symptoms that can significantly affect patients' quality of life. Treating this condition effectively while minimising treatment-related morbidity is of increasing importance as cancer patients are living longer from advances in oncological treatments. This clinical practice review discusses the implications of these advances on the decision to consider stenting as the initial treatment for SVCS. Stenting is increasingly popular as it provides quick symptomatic relief with low rates of complications. Systemic treatments have evolved in the past two decades with the development of immunotherapy and targeted therapies that have different response patterns compared to conventional chemotherapy. Furthermore, major changes have also been seen in radiotherapy techniques that allow treatments to better conform to targets while sparing normal tissues. These advances have changed practice patterns for stent placement in SVCS patients in both the localised and metastatic settings. Prospective studies using standardised patient-reported outcome tools are needed to determine the optimal treatment sequence for SVCS patients, as current recommendations are mainly based on retrospective single-arm studies. An individualized approach with multidisciplinary input is therefore important to optimize patient outcomes before more robust evidence is available.

Rapidly progressive osteoarthritis of hip: establishing and validating diagnostic criteria in the Southeast Asian population.

BACKGROUND: The study aimed to establish quantitative diagnostic criteria for rapidly progressive osteoarthritis (RPOA) of the hip and to compare the criteria with those for other pathological hip entities in the Asian population. METHODS: From July 2011 to September 2019, 126 patients who had undergone hip replacement were retrospectively recruited from a fast-track joint replacement list. Patient demographics and radiological parameters were evaluated. Diagnosis of hip RPOA was established based on Lequesne et al's criteria. The patients with RPOA, hip dysplasia, avascular necrosis, and primary osteoarthritis were allocated to the corresponding groups separately and compared. The diagnostic criteria of RPOA were established and validated in the sample population. RESULTS: Diagnosis of hip RPOA was confirmed in 18 patients. Their mean age at surgery (72 years) was significantly higher in this group than in the dysplasia and avascular necrosis groups. The mean pelvic tilt parameter (0.485) of RPOA group was significantly lower than those of other groups. The mean initial Tonnis angle (8.35°) of RPOA group was significantly higher than those of avascular necrosis and osteoarthritis groups. The differences were statistically significant between RPOA and non-RPOA groups in limb shortening rate, superior joint space narrowing, acetabular destruction, and head destruction (P < 0.05). Tonnis angle and lateral subluxation also increased significantly during the disease progression. CONCLUSION: Posterior pelvic tilt and increased Tonnis angle may contribute to the pathogenesis of RPOA, leading to progressive acquired acetabular obliquity and lateral subluxation. We propose the modern comprehensive diagnostic criteria be based on the existing literature and the current findings. Further external validation is recommended.

Computed Tomography for Calcaneal Fractures: Adding Value to the Radiology Report.

Computed tomography (CT) is nowadays the cornerstone for fracture pattern delineation in calcaneal fracture, and for operative planning. It is often challenging for radiologists in generating clinically oriented and meaningful CT reports to the orthopedic surgeon. The article aims to review the commonly encountered calcaneal injuries and highlight the key points in the description of these injuries and implications of the underlying classification system with respect to the surgeon's perspective. A thorough understanding of the pathoanatomy and potential complications of calcaneal fractures also helps radiologists in tailoring the radiology report in contribution to overall patient's management and prognostication. By doing so, we suggest ways in which the radiologists can add value to the radiology report.

Gallium-67 Scan with Single Photon Emission Computed Tomography for the Evaluation and Monitoring of Infected Abdominal Aortic Aneurysms: A 10-Year Case Series.

PURPOSE: This study aimed to evaluate the role of gallium-67 single photon emission computed tomography (SPECT) with contrast computed tomography (CT) in the evaluation and monitoring of infected abdominal aortic aneurysms (IAAA). MATERIALS AND METHODS: A retrospective cohort analysis was performed using prospectively collected data of consecutive patients with IAAA in Princess Margaret Hospital in Hong Kong between January 2010 and December 2020. The patients were identified using the Radiology Information System. RESULTS: All five patients had proven IAAA on CT and/or metabolic imaging. Among them, three were further supported by positive blood culture results. Gallium- 67 SPECT with contrast CT was useful in the detection of residual disease, monitoring, and detection of recurrence. CONCLUSION: Gallium-67 SPECT with contrast CT is helpful for evaluating IAAA. It serves an important role in guiding management, especially during long-term follow-up.

Hybrid Magnetic Resonance Imaging with Single Photon Emission Computed Tomography/Computed Tomography Bone Scan for Diagnosis Of Avascular Necrosis of Femoral Head.

Magnetic resonance imaging (MRI) is a commonly used imaging modality to detect early avascular necrosis (AVN). When MRI is inconclusive, bone scan is helpful in detecting AVN during early phase of the disease. As newer nuclear medicine equipment, such as single photon emission computed tomography/computed tomography (SPECT/CT) and positron emission tomography, are emerging in medical science, the role of these imaging modalities in AVN of femoral head is re-evaluated.

Hybrid method in severe pulmonary embolism not suitable for systemic fibrinolysis.

Acute massive pulmonary embolism is known to be associated with high mortality, and treatment options may be limited if systemic fibrinolysis is contraindicated. We report the exciting results of a novel mechanical-pharmacological hybrid approach in 3 patients with life-threatening massive pulmonary embolism, in whom systemic fibrinolysis was contraindicated.

Tibial tuberosity-trochlear groove distance in Chinese patients with or without recurrent patellar dislocation.

PURPOSE: To compare the tibial tuberosity-trochlear groove (TTTG) distance in Chinese patients with or without recurrent patellar dislocation. METHODS: The TTTG distance of 14 knees in 5 men and 9 women aged 16 to 38 years with recurrent patellar dislocation were compared with that of 73 control knees using magnetic resonance imaging. RESULTS: The mean TTTG distance was significantly greater in patients with recurrent patellar dislocation than in controls (16.4 mm vs. 10.1 mm, p<0.001). Six (43%) knees with recurrent patellar dislocation had the TTTG distance greater than the cut-off threshold of 16.4 mm, compared to none in controls. CONCLUSION: The TTTG distance is related to height and is shorter in Chinese than Caucasian patients; the threshold for tibial tuberosity transfer should be lower in Chinese patients.