Brain CT Research Articles

6504 Cerebellar Metastases from Papillary Thyroid Cancer; An Unusual Presentation

Abstract Disclosure: L.E. Chozet: None. A. Gilbert: None. M.A. Escobar Vasco: None. Background: Differentiated papillary thyroid cancer is known to have a very favorable prognosis. Brain metastases arising from papillary thyroid carcinoma are a very rare complication seen in approximately 1% of all cases of differentiated thyroid cancer with cerebellar metastases being even more uncommon. We present a case of a patient presenting with ataxia as the initial and only symptom of papillary thyroid carcinoma, found to have cerebellar metastases. Clinical Case: A 68-year-old man presented with ataxia for 1 week prior to arrival to hospital. CT head revealed hyperdense lesions in the right frontal lobe and left posterior cerebellar hemisphere. The patient underwent resection of left cerebellar mass with final pathology consistent with metastatic papillary thyroid carcinoma. Tumor cells were positive for TTF-1, thyroglobulin, CAM5.2, CK7, and PAX8, and negative for CK5/6, CK20, inhibin, and Napsin A. Ultrasound of the thyroid revealed multinodular goiter with dominant left thyroid lobe nodule 4 cm in size. PET CT showed left Thyroid mass with direct extension to adjacent lymph nodes, right anterior rib mass, left adrenal metastasis and right frontal lobe and left cerebellar metastasis. He received stereotactic radiosurgery with 5 out of 5 treatments completed. He subsequently underwent total thyroidectomy with left modified radical neck dissection, with pathology showing pT3bN1bM1. Next Generation Sequence positive for V600E, RADS1CR193, TERT PROMOTER -124C>T. After multidisciplinary team discussion, it was determined that the best course of action was to refer the patient to MD Anderson for evaluation, candidacy for prospective therapeutic clinical trials. Conclusion: This case demonstrates how differentiated papillary thyroid cancer, despite its favorable prognosis, can still prove to be a dangerous disease especially if undiagnosed for several years. This case also illustrates how papillary thyroid carcinoma can remain clinically silent for years and first present with atypical symptoms consistent with advanced metastases. Presentation: 6/2/2024

8472 A Little Too Much Of Tums: A Unique Presentation Of Milk Alkali Syndrome

Abstract Disclosure: Z. Al-Hiti: None. A. Misbah: None. Milk-Alkali Syndrome is characterized by a triad of hypercalcemia, metabolic alkalosis, and renal dysfunction. Historically associated with the excessive consumption of milk and alkali-containing antacids, it has re-emerged in recent years due to the widespread use of calcium and vitamin D supplements. It primarily results from an imbalance between calcium intake and renal excretion, leading to elevated calcium levels in the bloodstream. We present a case of milk-alkali syndrome with persistent renal dysfunction after normalizing calcium levels. We present the case of a 65-year-old male who presented to the emergency department with generalized weakness, poor oral intake, and confusion for 3 days. He was noted to have been more adherent with taking his prescribed medications over the last 2 weeks, which include calcitriol 0.5 mcg BID, calcium acetate 667 mg TID, and calcium carbonate 800 mg TID. On admission, he was afebrile and hemodynamically stable. . On examination, he had dry mucous membranes. He had no focal neurological deficits but he was confused and lethargic, and was only oriented to self. Other examination was noncontributory. Complete blood count and urinalysis were largely unremarkable. Chemistry demonstrated an elevated calcium level of 16.0 (8.3-10.6 mg/dL), ionized calcium of 7.3 (4.6-5.3 mg/dL), sodium of 134 (135-145 mmol/L), potassium of 5.4 (3.5-5.1 mmol/L), high phosphorus of 5.3 (2.4-5.1 mg/dL), and bicarbonate of 36 (20-31 mEq/L). Creatinine was elevated at 2.9 (0.6-1.1 mg/dL) from baseline of 1.3 to 1.4 mg/dL, and he had a BUN of 40(9-23 mg/dL). Venous blood gas showed a pH of 7.54( 7.32-7.42), pCO2 of 56 (40-52 mm Hg), and bicarbonate of 38 (23-28 mEq/L), indicating metabolic alkalosis. TSH was elevated at 36.15 (0.55- 4.78 uIU/mL) with a level of 140 two weeks back. Chest X-ray, renal ultrasound and CT head all showed no acute disease. Further work-up revealed a low PTH level of 6.3 (18.4-80 pg/mL), normal PTHrP level and 25-OH Vitamin D. There was no monoclonal gammopathy. Management included aggressive IV fluid resuscitation and IV calcitonin. However, no zoledronic acid was given due to a history of parathyroidectomy and risk of hypocalcemia. His serum calcium improved and eventually normalized. His confusion resolved. However, his creatinine and BUN increased to 3.4 mg/dL and 77, respectively, and did not improve to his baseline. This case highlights the importance of recognizing Milk-Alkali Syndrome as a potential consequence of over-the-counter calcium supplementation and highlights the potential for acute kidney injury which could be irreversible. Healthcare providers should be vigilant in identifying patients at risk, which includes older patients and patients with chronic kidney disease. Early recognition and appropriate management are crucial to prevent further renal deterioration and improve outcomes in individuals with Milk-Alkali Syndrome. Presentation: 6/2/2024

8358 A Diagnostic Challenge: Occult Paraganglioma Misdiagnosed as Pheochromocytoma Leading to Unnecessary Adrenalectomy

Abstract Disclosure: A.R. Kasireddy: None. S. Alshami: None. S. Gummalla: None. C. Balasubramaniapandian: None. J.A. Henske: None. A. Albashaireh: None. Background: Pheochromocytomas and paragangliomas are rare neuroendocrine tumors. Catecholamine-secreting paragangliomas, like pheochromocytomas, can present with hypertension, sweating and episodic headaches. Thoughtful consideration must be given to distinguish between the two and potentially avoid a critical misdiagnosis. Case: A 61-year-old woman with hypertension and diabetes presented for evaluation of glomus jugulare discovered on CT of the head during evaluation of worsening hearing loss and tinnitus. She reported a longstanding history of episodic headaches, palpitations, anxiety spells and excessive sweating with more recent onset of ear fullness. When symptoms first presented, she had a left adrenalectomy 3 years prior. CT abdomen at that time showed 1.8 x 2.2 cm left adrenal nodule with a density of 12.2 HU and early contrast washout. Plasma metanephrines were normal but normetanephrines were elevated at 5.1 nmol/L (nl: less than 0.9 nmol/L). 24-hour urine metanephrines were normal but normetanephrines were elevated to 892mcg/24h (nl: 122-676 mcg/24h). MIBG scan was done and showed increased activity in the left adrenal nodule. Decision was made to proceed with left adrenalectomy. Surgical pathology was benign. Present evaluation after discovery of the glomus tumour with worsening symptoms showed normal plasma metanephrines, elevated plasma normetanephrines at 1529.9 pg/ml (0- 285.2 pg/ml), elevated plasma norepinephrine at 3280 pg/ml (0-874 pg/ml), with normal dopamine and epinephrine levels. CT head showed a 3 x 2.7 x 2.1 cm lytic destructive mass within the petrous temporal bone at the left skull base containing multiple internal calcifications. Given the lab and imaging findings, paraganglioma was diagnosed. Genetic testing revealed SDHB mutation. Neurosurgery consultants determined that the tumour was not amenable to resection. She was treated with radiation therapy, alpha blockade, and close blood pressure monitoring. Discussion: This case highlights the importance of reviewing the degree of hormonal elevations as well as the pattern of elevation to obtain a correct diagnosis. Paragangliomas commonly secrete normetanephrines rather than metanephrines and are often not immediately localized. Understanding the most likely genetic mutations when a paraganglioma is suspected can direct appropriate choice of radionuclide scanning agents. In this case, an earlier diagnostic scan may have prevented unnecessary adrenalectomy and facilitated earlier discovery of the paraganglioma. Presentation: 6/2/2024

8719 Epidermal Inclusion Cyst Masquerading as Obstructive Craniopharyngioma

Abstract Disclosure: M. Murugesh: None. F. Thelmo: None. J. Watari: None. The most common cause of a sellar mass is notably pituitary adenoma (84.6%), followed by craniopharyngioma (3.2%), cystic nonneoplastic lesion (2.8%), inflammatory lesion (1.1%), meningioma (0.94%). Epidermoid cysts are benign congenital inclusion cysts that can occur anywhere in the body, with about 7% percent occurring in the head and neck region. Very rarely, they can present intracranially, accounting for about 0.3-1.8% of primary tumors. We present a rare case of epidermoid cyst growing as a suprasellar mass causing hypopituitarism.A 58-year-old female presented to the emergency department with dizziness in the setting of an ear infection. CT head showed 2.8 cm complex suprasellar mass, with adjacent 1 cm nodule at the cerebellopontine angle. MRI showed 2.7 x 2.4 x 2.7 cm suprasellar mass along with “a lobular component along the left posterior aspect extending to the cerebellopontine angle which measures about 1.3 cm, causing mass effect on the midbrain, pons, and optic chiasm”. The differential included craniopharyngioma, macroadenoma and meningioma. Notably, she denied any vision changes. She was evaluated by neurosurgery and after extensive multidisciplinary discussion with ENT and ophthalmology, the patient proceeded with endoscopic surgery for mass resection. Intra-operatively, the mass was noted to be densely adherent to the basilar artery, and sub-total resection was performed. Surprisingly on pathology the mass was identified as an epidermoid cyst, as evidenced by debris with cholesterol clefts and no lesional cells. The patient was started empirically on hydrocortisone 50mg three times a day post-resection. Endocrinology was consulted postoperatively with initial concerns of diabetes insipidus in the setting of hypernatremia, however, the patient’s sodium levels normalized. Pituitary panel at this time was concerning for central hypothyroidism (TSH 0.53 and FT4 0.8) and central adrenal insufficiency (ACTH <9 and AM cortisol 0.9). She was ultimately discharged on prednisone 5mg and levothyroxine 75 mcg with outpatient follow-up. While epidermoid cysts are present in the head and neck region about 7% of the time, they rarely occur in intracranial regions, with about 1.5% of intracerebral epidermoid cysts occurring intracranially. They tend to be slow growing and are often found only when they grow large enough to become symptomatic, as seen in our presented case. Our case highlights the importance of recognizing epidermoid cysts as a rare cause of sellar masses. Presentation: 6/1/2024

8186 Hypoglycemia as an Unusual Presentation of Panhypopituitarism

Abstract Disclosure: P. Chalasani: None. M. Asfaw: None. M. Mansour: None. M. Hammoud: None. T. Altaweel: None. H. Ilyas: None. L. Lawrence: None. Introduction: Hypopituitarism refers to the diminished or complete absence of anterior pituitary function, which may arise from acquired or congenital factors. The symptoms depend on the patient’s age and the hormones affected. We report a case where hypoglycemia led to a new diagnosis of panhypopituitarism in an adult patient. Clinical Case:A 53-year-old female with a past medical history of hypertension was brought to the emergency department after syncope. Patient experienced diaphoresis and loss of consciousness associated with urinary incontinence. She did not have confusion, tongue biting, or muscular weakness after the episode. On presentation, the patient was hypoglycemic with blood glucose of 39 mg/dl and received IV dextrose. No focal neurologic deficits were noted on physical examination. She was mildly hypotensive with blood pressure 98/66 mmHg, and received hydrocortisone 100 mg IV once, and started on IV dextrose infusion. Hypoglycemia workup revealed elevated insulin 16.6 uIU/mL and C-peptide 4.8 ng/mL (1.1-4.4) levels for a blood glucose level of 132 mg/dl, with normal beta-hydroxybutyrate of 0.14 mmol/L (0.02-0.27). Sulfonylurea screen was negative. CT abdomen revealed no pancreatic lesions or abnormalities. Hyperinsulinemia was attributed to insulin resistance in this patient with a BMI of 34 kg/m2. CT head revealed a heterogeneous low-density expansile mass in the sella/suprasellar region measuring approximately 2.5 x 2.3 x 2 cm. MRI brain confirmed a heterogeneous sellar mass with suprasellar extension measuring 3.4 x 2.3 x 2.1 cm abuting the optic chiasm without displacement. Biochemical workup revealed panhypopituitarism with secondary adrenal insufficiency ACTH < 1.5 pg/mL (7.2-63.3) and cortisol 3.63 ug/dL (3.70-19.40); secondary hypothyroidism TSH 0.84 mIU/mL (0.27-4.20) and FT4 < 0.50 ng/dL (0.70-14.8); growth hormone deficiency with low IGF-1 23 ng/mL (65-216); secondary hypogonadism FSH < 1 mIU/mL (46-177), LH < 1 mIU/mL (7.7-59) and estrone < 6 pg/mL (0-125); with normal prolactin 14.1 ng/mL (4.8-23.3). Patient revealed she had been amenorrheic since 23 years old and conceived one child prior. Patient was transitioned to oral hydrocortisone 20 mg AM and 10 mg PM, and started on levothyroxine 50 mcg PO daily. No neurosurgical intervention was recommended. Subsequently, patient requested a second opinion and was transferred to a tertiary center. Conclusion: The link between hypoglycemia and hypopituitarism, may be attributed to hypocortisolism and growth hormone / IGF-1 deficiency. Intriguingly, this patient's initial clinical presentation centered around hypoglycemia, and further evaluation led to the identification of a sellar mass and new diagnosis of panhypopituitarism. This case demonstrates the need to include hypopituitarism in the differential when evaluating hypoglycemic patients. Presentation: 6/2/2024

6553 Remission of Cushing’s Disease on Day 6 Post Transsphenoidal Surgery

Abstract Disclosure: M.N. Abdou: None. H. Alhumaidi: None. Background: Current recommendations for steroids replacement in the immediate post-operative (post op) period after transsphenoidal surgery (TSS) for patients with Cushing’s Disease (CD) are heterogenous and can be misleading. Monitoring daily morning cortisol for 72 hours post TSS with replacing steroids only after detecting low morning cortisol or signs of adrenal insufficiency (AI) has been mentioned in several studies. While some studies recommend either empiric steroids replacement on discharge regardless of status of remission or longer hospital stay for closer cortisol monitoring, others recommended monitoring for 3-4 days and starting steroids on discharge only if morning cortisol was < 415 nmol/L. Case: 60 years old female with a history of type 2 diabetes mellitus, hypertension and dyslipidemia was referred for an evaluation of a pituitary macroadenoma. She had an incidental finding of a pituitary mass measuring 25 mm on a CT brain obtained after a fall 3 months prior to her current visit. MRI pituitary gland revealed a 25x23x22 mm suprasellar mass with cavernous sinus invasion. She reported weight gain and worsening of diabetes control over the 2 years prior to her presentation. On exam, weight was 80 kg, BMI 32.5, BP 110/69, vital signs were otherwise normal. She had central obesity, facial plethora, and frontal hair thinning. Hormonal workup showed elevated 1 mg dexamethasone suppression test: 341 nmol/L (<55). 24h UFC was also high 233 nmol/24 hours (38-208). Morning cortisol 15.5 mcg/dl (6-18) with ACTH 228 pg/ml (7.2-63.3). Prolactin 581 mIU/L (58-418). FSH and LH were at the premenopausal range. TSH, FT4, and IGF-1 were normal. HBA1C 8%. Results were consistent with CD with central hypogonadism and mild elevation of prolactin likely due to stalk effect. Patient was admitted to the hospital for TSS. She had no surgical complications, and no steroids were used to monitor remission. Daily morning cortisol was measured after the surgery, readings were (1631, 668, 469, 224, 318, 110 nmol/l) day 1-6 (D1-D6) post op. She was started on oral Hydrocortisone (HC) 15 mg in the morning and 10 mg in the afternoon on D6 post op after documentation of cortisol level of 110 nmol/l. She was vitally stable and had no signs of AI before starting steroids. 1 day after starting oral HC she developed hypotension and hyponatremia. IV HC 100 mg was given immediately followed by 50 mg every 6 hours. Blood pressure improved with stress dose steroids. She was discharged home on HC 20 mg three times daily, tapered to reach 15, 10 over a period of 2 weeks. Conclusion: We present a case of CD that had a nadir morning cortisol on D6 post op in whom a diagnosis of fatal AI would have been missed if recommendations from some studies were followed. This case highlights the importance of prolonged monitoring for adrenal insufficiency if steroids were not used after surgery for CD. Presentation: 6/1/2024

6797 Pituitary Apoplexy as initial Presentation of IgG4-Related hypophysitis

Abstract Disclosure: M. Alameri: None. A. Alnuaimi: None. Introduction: IgG4-related hypophysitis is a rare disease due to IgG4 lymphoplasmacytic infiltration of the pituitary gland. It can either be isolated or part of a multisystemic disease. We report a rare case of pituitary apoplexy as first manifestation of IgG4-RD. Case report: A 27-year-old previously healthy male presented to emergency department with severe headache, nausea, vomiting and visual impairment. CT brain showed a large sellar suprasellar mass of 3cm with thick rim enhancement. Blood test showed evidence of central adrenal insufficiency, central hypothyroidism and secondary hypogonadism. Patient was started on hormone replacement therapy for central adrenal insufficiency and central hypothyroidism. Pituitary magnetic resonance imaging (MRI) demonstrated a 3.1 x 2.4 x 2.4 cm well-defined large sellar suprasellar mass with thick rim enhancement with intrinsic heterogeneous T2 signal with hypointense T1 signal on fat-suppressed post contrast imaging consistent with necrotic haemorrhagic suggestive of pituitary apoplexy and background of hypophysitis. Upward displacement of optic chiasm was noted without involvement of cavernous sinus. The patient was initially treated with high-dose steroids aiming for reduction of the pituitary mass. However, eventually, he underwent transsphenoidal surgery due to alternated level of consciousness. Pituitary histopathology showed that vast majority of the tissue is necrotic. A small fragment of viable anterior pituitary tissue is present, which measures up to 5.5 mm in greatest dimension which exhibited marked chronic inflammation, predominantly comprised of small lymphocytes. Plasma cells were present and staining with IgG/IgG4 revealed two high-power fields with clusters of approximately 25 and 50 IgG4 positive plasma cells, respectively. Blood test showed elevated blood IgG4 levels of >2.60 g/L (normal reference range 0.03-2.01 g/L). Case was discussed at Endocrine MDT meeting which agreed that blood tests result along with histopathology findings were in keeping with IgG4-Related hypophysitis as per the Mayo Clinic, Leporati and Japan-Korea proposed criteria. Because blood IgG4 levels were elevated, a systemic evaluation was performed. No evidence of other systemic disease found. High dose steroid therapy was initiated, which reduced remnant inflammatory sellar changes. Discussion and conclusion: IgG4-related pituitary disease should be considered as differential diagnosis in unusual presentations of pituitary apoplexy in the context of sellar suprasellar hypophysitis. Presentation: 6/2/2024

A-090 Performance of GFAP and UCH-L1 Biomarkers for Traumatic Brain Injury in the ARCHITECT i1000SR TBI Test

Abstract Background Traumatic Brain Injury (TBI) has been recognized as an important cause of death and disability and is a growing public health problem. An estimated 69 million people globally experience a TBI annually. The vast majority (80%) of patients evaluated for TBI in the Emergency Department will receive head CT scans, however less than 10% will have findings of acute traumatic abnormalities. This highlights the need for objective, rapid, accurate tools to help clinicians evaluate and triage patients with suspected TBI and reduce unnecessary radiation exposure. Blood based biomarkers such as glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) have shown utility to predict acute traumatic intracranial injury on CT scan after TBI. Methods The ARCHITECT TBI test is a panel of in vitro diagnostic chemiluminescent microparticle immunoassays for the measurement of GFAP and UCH-L1 in plasma and serum. A method comparison study was performed to compare the GFAP and UCH-L1 assays on ARCHITECT i1000SR to the FDA cleared Alinity i assays. Performance characteristics such as detection limits, imprecision, linearity, and measuring interval were established following CLSI guidance. Results The analytical measuring interval (AMI) extends from the limit of quantitation (LoQ) to the upper LoQ and is determined by the range that demonstrates acceptable performance for linearity, imprecision, and bias. The AMI is 6.1 to 42,000 pg/mL for GFAP and 26.3 to 25,000 pg/mL for UCH-L1. Within-laboratory imprecision ranged from 2.2 to 6.2% CV for GFAP and 2.2 to 4.5% CV for UCH-L1. The Overall Reproducibility (includes repeatability, between-run, between-day, between-instrument variance components) results ranged from 2.7 to 6.8% CV for GFAP and 2.4 to 3.9 %CV for UCH-L1. The method comparison study evaluated 123 specimens across the range of 6.5-32,548.6 pg/mL for GFAP, and 51.5-24,127.7 for UCH-L1. The correlation coefficients were 1.0, with a slope of 1.03 and 1.06, an intercept of -0.6 and -6.0, for GFAP and UCH-L1, respectively. The results support use of the established GFAP and UCH-L1 cutoffs and clinical performance findings in a multi-site pivotal study which enrolled 1899 mild TBI (Glasgow Coma Scale score 13 to 15) subjects. 116 of the 120 specimens with a positive CT scan had a positive TBI interpretation (Sensitivity 96.7%). Of the 1779 subjects with negative CT scan results, 713 had a negative TBI interpretation (Specificity 40.1%). The negative predictive value (NPV) of the test was 99.4% (713/717). Conclusions The ARCHITECT TBI test performance was evaluated compared to the Alinity i TBI test across a broad concentration range of GFAP and UCH-L1. The results support equivalence of the ARCHITECT TBI test to the Alinity i TBI test. The established cutoffs were evaluated in a prospective cohort of mild TBI subjects and demonstrated high sensitivity and NPV relative to head CT scan results, supporting the utility to rule out the need for CT scan in mild TBI subjects presenting to the emergency department. Funding This work is in collaboration with the US Army Medical Materiel Development Activity, US Army Medical Research and Development Command CRADA 20-1266-CRA.

The influence of miscentering on radiation dose during computed tomography head examinations and the role of localiser orientation: A phantom study

IntroductionComputed Tomography (CT) chest, abdomen and pelvis research demonstrates a relationship between vertical phantom positioning and radiation dose. Moving the phantom closer or further from the x-ray source results in magnification or minimisation of the localiser. As automatic tube current modulation (ATCM) algorithms use localisers to estimate patient size and calculate required tube current, magnification or minimisation results in the incorrect provision of radiation dose. Radiation dose changes also depend on localiser orientation, changes with anteroposterior (AP) and posteroanterior (PA) localisers demonstrating an inverse relationship. However, within CT head literature often attributes radiation dose changes on impaired function of the bow-tie filter instead. The current study investigated the role of miscentering on ATCM function within CT head, paying particular attention to localiser orientation. MethodsHead scanning was performed with an anthropomorphic phantom at the isocentre, alongside ten vertically miscentered positions. This was performed three times, with an AP, PA and lateral localiser. CT dose index values at each miscentered level were compared across conditions. ResultsVertical miscentering altered radiation dose in both AP and PA conditions, radiation dose linearly increasing (up to 17.05%) when positioning the phantom closer to the x-ray source and decreasing when positioning away (up to −13.13%). Changes across AP and PA conditions demonstrated an inverse relationship. Radiation dose was unaffected in the lateral condition. ConclusionsMiscentering during CT head alters ATCM function due to magnification/minimisation of the localiser image, causing ATCM algorithms to misinterpret patient size and miscalculate required tube current. Implications for practiceRadiographers should be accurate when centering for CT head, avoiding any potential radiation dose changes. Further research into vertical miscentering and image quality during CT head is recommended.

Association of the Area Deprivation Index With Dementia Basic Workup and Diagnosis in Central and Western Virginia: A Cross-Sectional Study.

The Area Deprivation Index (ADI) provides a validated and multidimensional metric of areal disadvantage. Our goals were to determine if the ADI influences the likelihood of receiving workup based on published guidelines and an etiologic diagnosis of dementia in Central and Western Virginia. We collected deidentified data from the electronic health record of individuals aged 50-105 years diagnosed with dementia at the University of Virginia (UVA) Medical Center (2016-2021) and at Carillion Clinic (2018-2021). Visit-specific ICD-10 codes were used to classify each dementia diagnosis as "disease-specific" (e.g., Alzheimer disease) or "general" (e.g., unspecified dementia). Following the American Academy of Neurology guidelines, we considered the evaluation performed as "adequate" if patients had vitamin B12, thyroid-stimulating hormone, and brain CT or magnetic resonance imaging within 6 months of the initial diagnosis. Census tract ADI was linked to study participants using the unique census tract identifier derived from the participants' home addresses at the time of diagnosis. Statistical modeling occurred under a Bayesian paradigm implemented using a standard code in R. The study included 13,431 individuals diagnosed with dementia at UVA (n = 7,152) and Carillion Clinic (n = 6,279). Of those, 32.5% and 20.4% received "disease-specific" diagnoses at UVA and Carillion Clinic and 8.2% and 20.4% underwent "adequate" workup, respectively. The adjusted relationship between census tract ADI and the likelihood of a disease-specific diagnosis was U-shaped: Residence in moderately disadvantaged areas was associated with the lowest likelihood of disease-specific diagnosis. Most patients diagnosed with dementia did not receive an adequate evaluation or an etiologic diagnosis. Those living in locations just above the national median ADI levels had the lowest likelihood of receiving an etiologic diagnosis, lower than those in the least and most deprived areas. Renewed awareness efforts among providers are needed to increase compliance with diagnostic guidelines.

Image quality of virtual monochromatic and material density iodine images for evaluation of head and neck neoplasms using deep learning-based CT image reconstruction – A retrospective observational study

PurposeTo compare the quality of deep learning image reconstructed (DLIR) virtual monochromatic images (VMI) and material density (MD) iodine images from dual-energy computed tomography (DECT) for the evaluation of head and neck neoplasms with CT scans from a conventional single-energy protocol. MethodA total of 294 head and neck CT scans (98 VMIs operated at 60 keV, 102 MD iodine images, and 94 images from a 120 kVp single-energy CT (SECT) protocol) were retrospectively evaluated. VMIs and MD iodine images were generated using the Gemstone Spectral Imaging (GSI) mode using DLIR and metal artifact reduction (MAR) algorithms. SECT images were generated using adaptive statistical iterative reconstruction (ASIR-V). Images were scored by two independent readers on a 6-point Likert-type scale for overall image quality, vessel contrast, soft tissue contrast, noise texture, noise intensity, artifact reduction, and sharpness. ResultsSubjective overall image quality was rated as superior or excellent in 98 % of DLIR-based MD iodine images and VMIs, but only in 55 % of ASIR-V-based SECT images. For each individual quality criterion, image quality of VMIs and MD iodine images was rated as better than that of SECT images (p < 0.001 in each case). Noise texture and intensity were rated better in MD iodine images than in VMIs. ConclusionDECT using both DLIR and MAR for the generation of VMIs and MD iodine images resulted in higher subjective quality of oncologic head and neck images than ASIR-V-based SECT. Noise reduction and noise texture were best achieved with DLIR-based MD iodine images.

358 Reduction in Emergency Department Length of Stay and Head CT Utilization With Implementation of Brainscope in Head Injury Evaluation

358 Reduction in Emergency Department Length of Stay and Head CT Utilization With Implementation of Brainscope in Head Injury Evaluation

Longitudinal changes in the US emergency department use of advanced neuroimaging in the mechanical thrombectomy era.

To describe ED neuroimaging trends across the time-period spanning the early adoption of endovascular therapy for acute stroke (2013-2018). We performed a retrospective, cross-sectional study of ED visits using the 2013-2018 National Emergency Department Sample, a 20% sample of ED encounters in the United States. Neuroimaging use was determined by Common Procedural Terminology (CPT) code for non-contrast head CT (NCCT), CT angiography head (CTA), CT perfusion (CTP), and MRI brain (MRI) in non-admitted ED patients. Data was analyzed according to sampling weights and imaging rates were calculated per 100,000 ED visits. Multivariate logistic regression analysis was performed to identify hospital-level factors associated with imaging utilization. Study population comprised 571,935,906 weighted adult ED encounters. Image utilization increased between 2013 and 2018 for all modalities studied, although more pronounced in CTA (80.24/100,000 ED visits to 448.26/100,000 ED visits (p < 0.001)) and CTP (1.75/100,000 ED visits to 28.04/100,000 ED visits p < 0.001)). Regression analysis revealed that teaching hospitals were associated with higher odds of high CTA utilization (OR 1.88 for 2018, p < 0.05), while low-volume EDs and public hospitals showed the reverse (OR 0.39 in 2018, p < 0.05). We identified substantial increases in overall neuroimaging use in a national sample of non-admitted emergency department encounters between 2013 and 2018 with variability in utilization according to both patient and hospital properties. Further investigation into the appropriateness of this imaging is required to ensure that access to acute stroke treatment is balanced against the timing and cost of over-imaging.

192 - Assessing the Diagnostic Reference Levels of Head CT Scan at Garoua Regional Medical Imaging Center

192 - Assessing the Diagnostic Reference Levels of Head CT Scan at Garoua Regional Medical Imaging Center

Criteria for neurosurgical treatment of children and adolescents with traumatic brain injury in a Brazilian level 1 trauma center.

Considering Glasgow Coma Scale (GCS) scores and brain CT scans in a group of children and adolescents with traumatic brain injury (TBI), the scope of this study was to identify the criteria established for the indication of emergency neurosurgical treatment in a level 1 trauma center. This was a cross-sectional study with consecutive review of medical records of children and adolescents < 17 years with TBI who were hospitalized and underwent neurosurgical treatment between January 2016 and December 2023. Two groups were formed for analysis: patients with GCS scores ≤ 8 versus patients with GCS scores > 8. Based on the GCS score and brain CT scan of each patient, the authors investigated the criteria established for the surgical indications in this group. In the period considered for the study, 376 children and adolescents with TBI were hospitalized and 31% required neurosurgical treatment. The median age was 5 years (interquartile range 1-11 years) and there was a predominance of males (68%). Home accidents predominated in 77% of children < 5 years of age, whereas road accidents predominated among those older than 5 (47%). Diffuse brain lesions on CT scans predominated in patients with GCS scores ≤ 8 when compared to the group with GCS scores > 8 (89% vs 19%; p < 0.0001). Regarding neurosurgical access, decompressive craniectomies (70%) and invasive intracranial pressure monitoring (44%) prevailed among patients with GCS scores ≤ 8, whereas craniotomies for drainage of intracranial hematomas (70%) and surgical correction of depressed skull fracture (21%) prevailed among those with GCS scores > 8. Based on the GCS scores and CT scans, the authors were able to define the criteria used for neurosurgical indications in a Brazilian level 1 trauma center. They found a high prevalence of decompressive craniectomy in patients with severe TBI in their department due to the irregular supply of disposable catheters necessary for intracranial pressure monitoring.

Co-Occurrence Relationship Driven Hierarchical Attention Network for Brain CT Report Generation

Co-Occurrence Relationship Driven Hierarchical Attention Network for Brain CT Report Generation

Canadian CT head rule adherence in a rural hospital without in-house computed tomography.

We sought to determine the difference between Canadian CT Head Rule (CCHR) indicated imaging rates and actual imaging rates for patients with mild traumatic brain injuries (mTBIs) at a rural emergency department (ED) without in-house computed tomography (CT). In addition, we compared CCHR adherence at a hospital without CT to previous publications from centres with CT to determine if rural populations receive less CT imaging for minor head traumas when indicated by the CCHR. This retrospective chart review explored individuals who presented to a rural ED (no in-house CT scanner) with a primary diagnosis of mild head injury or concussion between 1 January 2017 and 31 December 2021. Information regarding CCHR criteria, transfer status and patient demographics was collected. Descriptive analyses were completed to determine the percentage of patients who received appropriate transfer for imaging, did not receive transfer for imaging when indicated and received unnecessary transfer. A total of 124 charts met our inclusion criteria (17 [12.1%] charts excluded), with 25.8% transferred to the nearest hospital for CT imaging. After applying the CCHR criteria to our charts, 62.1% were indicated for CT. Of the 62.1%, only 35.1% were transferred for imaging (51.2% of high-risk and 16.7% of medium-risk). By exploring CT rates for mTBIs in a rural Canadian ED, we found low transfer rates (35.1%) of CCHR-indicated patients for imaging needed to guide further healthcare decisions. This work highlights a discrepancy within the Canadian healthcare system between rural and urban centres and allows for opportunities to help narrow the gap in health care. Nous avons cherché à déterminer la différence entre les taux d'imagerie indiqués par le Canadian CT Head Rule (CCHR, règlement canadien relatif à la tomodensitométrie de la tête) et les taux d'imagerie réels pour les patients souffrant de traumatismes craniocérébraux légers (TCCL) dans un service d'urgence rural ne disposant pas d'une tomographie par ordinateur interne. En outre, nous avons comparé l'adhésion au CCHR dans un hôpital sans tomographie par ordinateur à des publications antérieures provenant de centres avec tomographie par ordinateur afin de déterminer si les populations rurales reçoivent moins d'imagerie par tomodensitométrie pour les traumatismes crâniens mineurs lorsque le CCHR l'indique. Cette étude rétrospective des dossiers a exploré les personnes qui SE sont présentées à une urgence rurale (sans tomodensitomètre interne) avec un diagnostic primaire de traumatisme crânien léger ou de commotion cérébrale entre le 1er janvier 2017 et le 31 décembre 2021. Les informations concernant les critères du CCHR, l'état de transfert et les données démographiques des patients ont été recueillies. Des analyses descriptives ont été réalisées pour déterminer le pourcentage de patients ayant reçu un transfert approprié pour l'imagerie, n'ayant pas reçu de transfert pour l'imagerie quand c'était indiqué et ayant reçu un transfert inutile. Au total, 124 dossiers répondaient à nos critères d'inclusion [17 (12,1%) dossiers exclus], dont 25,8% ont été transférés à l'hôpital le plus proche pour une imagerie par tomodensitométrie. Après avoir appliqué les critères du CCHR à nos dossiers, 62,1% d'entre eux étaient indiqués pour une tomodensitométrie. Sur ces 62,1%, seuls 35,1% ont été transférés pour imagerie (51,2% de haut risque, 16,7% de risque moyen). En explorant les taux de tomodensitométrie pour les TCCL dans un service d'urgence rural canadien, nous avons constaté de faibles taux de transfert (35,1%) des patients recommandés par le CCRH pour une imagerie nécessaire dans le but de guider les décisions de soins de santé ultérieures. Ce travail met en évidence un écart dans le système de santé canadien entre les centres ruraux et urbains et offre des opportunités pour aider à réduire l'écart dans les soins de santé.

328 - Evaluation of the usefulness of the MV3D RECON technique with Bone Removal in CT Brain Angiography

328 - Evaluation of the usefulness of the MV3D RECON technique with Bone Removal in CT Brain Angiography

Un caso de exoftalmos progresivo en una niña de 5 años

Introduction: spindle cell sarcoma is a rare tumor, with little presentation in the literature. Soft tissue tumors constitute a heterogeneous group, requiring a multidisciplinary approach. Clinical case: 5-year-old schoolboy who goes to his pediatrician for exophthalmos. His mother refers a progressive proptosis in the left eye of 6 months of evolution. No loss of visual acuity, in the last weeks intermittent pain with eye movements. On examination proptosis of the left eye with intermittent tearing and vascular lesion in the temporal portion of the same eye, he presented restriction of left eye movements. He was referred to the hospital emergency department where a head CT scan (Figure 1,2) was performed, revealing a unilateral left retroorbital lesion measuring 28 x 14 mm, causing proptosis, mass effect on retroocular structures and loss of ocular sphericity. Given the findings in the imaging tests, it was decided surgical intervention by means of frontotemporal craniotomy, subsequently receiving complementary treatment with local radiotherapy. Due to negative molecular pathology studies, the result was finally interpreted as undifferentiated 'adult-type' spindle cell sarcoma. Conclusion: although undifferentiated spindle cell sarcoma is a rare pathology, it should be included in the differential diagnosis of retro-orbital pathologies. The objective of this case is to review the main characteristics of spindle cell sarcoma, given its rapid and aggressive form of presentation, in a rare tumor.

An Audit Of Post Fall Medical Reviews In Older Hospital Inpatients

Abstract Background After an older person falls in hospital, the post-fall medical review is critical to assess injury and to put a plan in place to prevent further falls. We performed an audit to assess the post fall medical review and management of patients ≥65 years in a large university teaching hospital compared to national standard “Service User Falls: A Practical Guide for Review” and NICE Guidelines. Methods In a consecutive cohort of patients with falls, the post-fall medical review note was examined for crucial details from the history (mechanism, head/hip strike, loss of consciousness, pain) and examination (confusion, vital signs, joint assessment). In addition, we audited if there was an indication for CT Brain and compared to NICE criteria. Results 49 post fall medical review notes were audited (Mean age 79 years, range 66-96). 27% of patients who fell had a CT Brain. 6% (3/49) of patients who fell met NICE criteria for CT Brain, but it was not performed. Conclusion A significant proportion of post fall medical reviews omit important details that could help diagnostically and to inform a plan to prevent further falls. There is limited guidance for clinicians as to when to order a CT Brain for inpatient falls. We plan to introduce a post fall medical review pro forma/checklist and to standardise a CT Brain decision tool. We will then re-audit post introduction of these to assess for quality improvement.