Normative parameters of the Evans Index using Computer Tomography in the Saudi population.

OBJECTIVES: To calculate The Evans Index (EI) in normal Individuals. Ventricular enlargement is referred to as hydrocephalus. Computer tomography (CT) scans are commonly used to investigate such intracranial pathologies. The EI is an important parameter for diagnosing hydrocephalus. METHODS: We included all patients who underwent Computer tomography (CT) scan of the brain that was reported as normal. The mean EI was calculated for the whole sample stratified by age, gender, and ethnicity. Patients with an initial report indicating any intracranial pathology, such as hydrocephalus, tumors, hemorrhages, or neurodegenerative disorders, were excluded. RESULTS: A total of 1,330 brain CT scans carried out at our institution were reviewed retrospectively from August 2021 to December 2021. A total of 423 CT scans were screened after excluding 25 patients with abnormal imaging findings and 14 repeated images for the same patients. A total of 384 patients were included. The mean EI for the entire sample was 0.2550±0.0277. There was a minimal but statistically significant difference based on gender, with a mean EI of 0.2588±0.0274 for males and 0.2517±0.0276 for females (p=0.012). There was no statistically significant difference between Saudi and non-Saudi patients. EI increased progressively with age in both genders. CONCLUSION: Our EI values were similar to many of those reported in other countries, which supports the use of the 0.3 cutoff for the diagnosis of hydrocephalus, regardless of gender, age, or ethnicity.

Accuracy of ultrasound in predicting thyroid malignancy: a comparative analysis of the ACR TI-RADS and ATA risk stratification systems

ABSTRACT Objective: Thyroid nodules are very common in clinical practice, and ultrasound has long been used as a screening tool for their evaluation. Several risk assessment systems based on ultrasonography have been developed to stratify the risk of malignancy and determine the need for fine-needle aspiration in thyroid nodules, including the American Thyroid Association (ATA) system and the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS). The aim of this study was to compare the performance of the ATA and ACR TI-RADS systems in predicting malignancy in thyroid nodules based on the nodules' final histopathology reports. Materials and methods: We performed a retrospective review of medical records to identify patients who underwent thyroid surgery at King Abdulaziz University from 2017 to 2022. The ultrasound features of the nodules with confirmed histopathology (benign versus malignant) were evaluated. Both ATA and ACR TI-RADS scores were documented. Results: The analysis included 191 patients who underwent thyroid surgery and fulfilled the inclusion criteria. Hemithyroidectomy was performed in 22.5% of the patients, and total thyroidectomy was performed in 77.0% of them. In all, 91 patients (47.6%) were found to have malignant nodules on histopathology. We then compared the histopathology reports with the preoperative ultrasonographic risk scores. The estimated sensitivity and specificity in identifying malignant nodules were, respectively, 52% and 80% with the ATA system and 51.6% and 90% with the ACR TI-RADS system. Conclusion: Both ATA and ACR TI-RADS risk stratification systems are valuable tools for assessing the malignancy risk in thyroid nodules. In our study, the ACR TI-RADS system had superior specificity compared with the ATA system in predicting malignancy among high-risk lesions.

Subependymal Giant Cell Astrocytoma Apoplexy: A Case Report and Systematic Review.

Subependymal giant cell astrocytoma (SEGA) is the most common intracranial tumor in tuberous sclerosis (TS) patients. The tumor generally localizes in the proximity of Monro's foramen; as it grows, it subsequently causes hydrocephalus and increases intracranial pressure (ICP). However, acute symptoms of increased ICP due to intratumoral bleeding rarely manifest in SEGA patients. We present a 27-year-old male with TS who presented due to hemorrhagic complications of SEGA with intratumoral bleeding and vitreous orbital hemorrhage. We then conducted a systematic review with four databases (PubMed, Web of Science, Google Scholar, and Cochrane) to identify similar cases using the following keywords: "Subependymal giant cell astrocytoma," "Hemorrhage," "Haemorrhage," and "Bleeding." Our review identified 12 articles reporting 14 cases of hemorrhagic complications of SEGA in addition to our case report. The median age of diagnosis was 21 (range 5-79) years with unequal gender distribution (M:F ratio, 11:4). Headache was the most presented symptom, followed by hemiparesis, seizure, altered mental status, visual deterioration, and headache accompanied by seizure. TS was seen in most of the cases (80%). Gross total resection (GTR) was achieved in 53.5% of the patients. Regarding the clinical outcome, 66.7% had a good outcome, 20% died, and 13.3% had no report of their outcomes. No tumor recurrence was seen in the cases with a reported duration of follow-up. Catastrophic presentation of SEGA apoplexy is a rare occurrence. We present a case report with a systematic review and discuss SEGA apoplexy's possible pathophysiology and outcome.

Virtual and Traditional Learning in Undergraduate Radiology Education: A Cross-sectional Comparative Study from Saudi Arabia.

Background: The coronavirus pandemic (COVID-19) resulted in disruption in the traditional teaching methods and lead to a wider adoption of virtual teaching. However, there is a lack of comparative studies regarding the use of either or the mixed mode for teaching radiology to undergraduate students. Objective: This study aimed to determine the barriers, performance, and overall satisfaction of undergraduate medical students and instructors undertaking virtual and traditional radiology learning across Saudi Arabia. Methodology: This cross-sectional questionnaire study included undergraduate students and instructors from across Saudi Arabia who had undertaken radiology either traditionally, through E-learning, or both in the 2019-20 academic year. The questionnaire elicited information regarding attendance, teaching methods, difficulties, knowledge acquisition, and satisfaction. Association between variables was assessed using Chi-square, in addition to a univariate analysis. Results: A total of 404 undergraduate students from 28 universities of Saudi Arabia responded, in addition to 20 instructors. Students preferred E-learning for the quality of the course and the time and effort spent as well as obtained higher grades than those in traditional learning. Traditional education was favored over E-learning for clarity of instructors' voice, ease of understanding image description by the instructor, and lack of technical barriers such as poor Internet connection. The form of education was significantly correlated with grades obtained (P < 0.001) but not with overall satisfaction (P = 0.067). The majority of the instructors (60%) considered E-learning to be helpful in balancing their workload and teaching responsibilities (P = 0.029) and would recommend it as a standard teaching method for radiology (85%). Conclusion: E-learning has potential advantages over traditional learning for teaching radiology to undergraduate medical students. However, further optimization is required to overcome the current deficiencies of this mode.

Substantia nigra micro-haemorrhage causing ipsilateral unilateral Parkinsonism and abnormal dopamine transporter scan uptake.

Parkinsonism is a commonly seen movement disorder syndrome with neurodegenerative and non-neurodegenerative causes. Presynaptic dopamine transporter (DaT) single-photon emission computed tomography (SPECT) imaging is the most commonly used imaging technique in clinical practice to differentiate degenerative Parkinson's disease (PD) and PD plus syndromes from other causes such as essential tremor and drug-induced parkinsonism. This can help identify the patients who would benefit from medical therapy due to underlying pre-synaptic dopaminergic deficits. We report a case of unilateral parkinsonism caused by ipsilateral substantia nigra micro-haemorrhage resulting in disruption of the nigrostriatal pathway. This is an unusual case of a 55-year-old male patient who presented with unilateral Parkinsonism a decade after significant head trauma where MRI plays a critical and complementary role in diagnosing complete interruption of the nigrostriatal pathway due to cerebral micro-haemorrhage. The case also beautifully demonstrates the anatomy of the nigrostriatal pathway where a small lesion in the substantia nigra caused complete loss of radioligand uptake in the ipsilateral corpus striatum. Physicians should be aware of the importance of structural imaging in atypical movement disorder cases and, in particular, the routine use of susceptibility-weighted sequences (SWI).

Balint syndrome (chronic visual-spatial disorder) presenting without known cause.

Balint's syndrome is a rare disorder characterized by a triad of simultanagnosia, optic apraxia, and ocular apraxia. The syndrome manifests when there is an injury to the posterior parietal and occipital lobes and is often bilateral. Several causes of this syndrome were published in the literature, such as trauma, infarctions, infections, tumors, and pre-eclampsia. It can also be the presenting feature of several neurodegenerative disorders, such as atypical Alzheimer's disease. We report a case of a 62-year-old lady who presented with simultanagnosia, optic apraxia, and ocular ataxia which are the typical signs and symptoms of this syndrome. Neuropsychological evaluation revealed severe affection of the visual-spatial function with intact memory, language, and cognition. Brain imaging confirmed atrophy and decreased perfusion in the posterior parietal and occipital lobes. No underlying cause could be identified to explain the brain parenchymal atrophy. The follow-up neuropsychological assessment and brain imaging did not show any progression confirming the static course of the disease.