Developing a production workflow for 3D-printed temporal bone surgical simulators.

INTRODUCTION: 3D-printed temporal bone models enable the training and rehearsal of complex otological procedures. To date, there has been no consolidation of the literature regarding the developmental process of 3D-printed temporal bone models. A brief review of the current literature shows that many of the key surgical landmarks of the temporal bone are poorly represented in models. This study aims to propose a novel design and production workflow to produce high-fidelity 3D-printed temporal bone models for surgical simulation. METHODS: Developmental phases for data extraction, 3D segmentation and Computer Aided Design (CAD), and fabrication are outlined. The design and fabrication considerations for key anatomical regions, such as the mastoid air cells and course of the facial nerve, are expounded on with the associated strategy and design methods employed. To validate the model, radiological measurements were compared and a senior otolaryngologist performed various surgical procedures on the model. RESULTS: Measurements between the original scans and scans of the model demonstrate sub-millimetre accuracy of the model. Assessment by the senior otologist found that the model was satisfactory in simulating multiple surgical procedures. CONCLUSION: This study offers a systematic method for creating accurate 3D-printed temporal bone models for surgical training. Results show high accuracy and effectiveness in simulating surgical procedures, promising improved training and patient outcomes.

Case of infiltrative optic neuropathy with hypertrophic pachymeningitis as a manifestation of en plaque meningioma.

We describe a case of infiltrative optic neuropathy with hypertrophic pachymeningitis noted on MRI of the brain, presenting a diagnostic dilemma with a wide variety of differential diagnoses to consider. Our patient is a middle-aged woman with a 20-year history of migranous-sounding headaches who was incidentally found to have worsening vision in her left eye during a routine driving test visual acuity check. Neurological examination revealed a left grade III relative afferent pupillary defect and a central scotoma with red desaturation. Subsequent MRI of her brain and anterior visual pathway revealed features suggestive of an infiltrative left optic neuropathy with hypertrophic pachymeningitis. An extended workup including diagnostic lumbar puncture and blood tests for possible autoimmune, infective and neoplastic causes proved unyielding. Eventually, an endoscopic transsphenoidal biopsy helped to clinch the diagnosis of a (meningothelial subtype) WHO grade 1 meningioma as the cause of her clinical and radiological presentation.

Appropriateness of lumbar spine radiography and factors influencing imaging ordering patterns: paving the path toward value-driven health care.

The demand for diagnostic imaging continues to rise. Against the backdrop of rising health care costs and finite resources, this has prompted a paradigm shift toward value-driven patient care. Inappropriate imaging is a barrier toward achieving this goal, which runs counter to prevailing evidence-based guidelines and contributes to rising healthcare costs. Our objective was to evaluate the appropriateness of lumbar spine X-rays in a tertiary referral Emergency Department (ED) and assess whether physicians' specialization and years of experience influence appropriateness. A total of 1030 lumbar spine radiographs performed in the ED of an academic medical center over a consecutive 3-month period were reviewed retrospectively. Referral indications were reviewed for adherence to 2021 American College of Radiology appropriateness guidelines for lower back pain, and referral patterns were evaluated among physician groups based on specialists' training and years in practice. 63.8% of lumbar spine radiographs were appropriate, with trauma being the most common indication. 36.2% of orders were inappropriate, with lower back pain of <6 weeks duration being the most common indication. Significant differences in inappropriate orders were found (P < .001) across physician groups: qualified Emergency Medicine specialists (20.9% inappropriate orders), specialists in training (27.8%), and non-specialists with ≥3 (60.0%) and <3 (36.9%) years in practice, respectively. Approximately one-third of lumbar spine radiographs performed in the ED were inappropriately ordered by American College of Radiology guidelines; specialists training and years in practice affected referral patterns. Integrating evidence-based appropriateness guidelines into the physician order workflow and targeting older non-specialists may promote more judicious imaging and reduce health care costs.

SingHealth Radiology Archives pictorial essay Part 2: gastroenterology, musculoskeletal, and obstetrics and gynaecology cases.

The Singapore Health Services cluster (SingHealth) radiology film archives are a valuable repository of local radiological cases dating back to the 1950s. Some of the cases in the archives are of historical medical interest, i.e. cerebral angiography in the workup of patients with hemiplegia. Other cases are of historical social interest, being conditions seen during earlier stages of Singapore's development, i.e. bound feet. The archives form a unique portal into the development of local radiology as well as the national development of Singapore. A selection from the archives is published in commemoration of the International Day of Radiology in 2020, as well as the 200th anniversary of the Singapore General Hospital in 2021. This pictorial essay comprises gastroenterology, musculoskeletal and obstetrics and gynaecology cases from the archives.

SingHealth Radiology Archives pictorial essay Part 1: cardiovascular, respiratory and neurological cases.

The Singapore Health Services cluster (SingHealth) radiology film archives are a valuable repository of local radiological cases dating back to the 1950s. Some of the cases in the archives are of historical medical interest, i.e. cerebral angiography in the workup of patients with hemiplegia. Other cases are of historical social interest, being conditions seen during earlier stages of Singapore's development, i.e. bound feet. The archives form a unique portal into the development of local radiology as well as the national development of Singapore. A selection from the archives is published in 2020 in commemoration of the 20th anniversary of the formation of SingHealth, the 55th National Day of Singapore, and the 125th anniversary of the International Day of Radiology. This pictorial essay comprises cardiovascular, respiratory and neurological cases from the archives.

Capecitabine-induced leukoencephalopathy involving the bilateral corticospinal tracts.

An 80 year old lady with a history of metastatic sigmoid carcinoma presented with expressive dysphasia and unsteady gait 4 days after commencement of adjuvant capecitabine chemotherapy. MRI demonstrated restricted diffusion and T2/FLAIR hyperintensity involving the course of the bilateral corticospinal tracts, the corpus callosum and the middle cerebellar peduncles. Discontinuation of chemotherapy lead to symptom resolution in 2 days; repeat MRI at 2 months demonstrated reversal of the diffusion changes and improvement of the previous T2W/FLAIR hyperintensity. This report describes the first case of capecitabine induced leukoencephalopathy causing restricted diffusion along the corticospinal tracts, which should be differentiated from other entities that involve the corticospinal tracts (i.e. amyotrophic lateral sclerosis (ALS), primary lateral sclerosis (PLS), hypoglycemic coma, etc.).