Small Lesions Research Articles

12618 A Rare Case Of Diabetic Ketoacidosis Leading To Severe Hypertriglyceridemia-induced Necrotizing Pancreatitis

Abstract Disclosure: E.R. Perez Roman: None. D.A. Lopez Rodriguez: None. K. Ramirez Gorbea: None. M. Sanchez Cordero: None. Y. Garcia Cruz: None. Acute pancreatitis is an acute inflammatory process of the pancreas that if left untreated can become complicated resulting in multiple organ damage and a fatal outcome in approximately 10%-40% of patients. There are well-known causes that can lead to pancreatitis such as alcohol, hereditary disorders, cholelithiasis, prior pancreatitis, and medications. Less frequently, it can be related to poorly controlled diabetes mellitus and diabetic ketoacidosis (DKA), given that in a state of low or deprived insulin, there is a breakdown of triglycerides into toxic fatty acids by pancreatic lipases; this lipotoxicity can result in the development of acute pancreatitis. We present a case of a 50-year-old woman with a past medical history of untreated hyperlipidemia and previous pancreatitis who was transferred to our institution with acute epigastric pain radiating to the back, nausea, and persistent vomiting. Upon arrival, blood glucose was 299 mg/dL, HbgA1c of 11.4%, lactic acid of 3.6 mmol/L, hypocalcemia of 6.0 mg/dl, hypoalbuminemia, and elevated pancreatic enzymes, amylase 869 U/L and lipase 2,493 U/L. The lipid panel was remarkable for total cholesterol of 1,085 mg/dL and triglycerides of 4,369mg/dL. Abdominopelvic CT scan confirmed acute pancreatitis with extensive peripancreatic and regional mesenteric edema. This patient was treated with aggressive IV fluid resuscitation and treated for DKA as per protocol. Despite prompt treatment, the patient rapidly deteriorated, developing pulmonary effusions and impending respiratory failure requiring mechanical ventilation. Her hyperglycemia was challenging to control and in the setting of severe hypertriglyceridemia, insulin requirements were higher, as intravenous insulin is useful in patients with concomitant findings, in the absence of plasmapheresis availability. Despite the marked reduction of triglyceride to 978 mg/dL and a decrease in pancreatic enzymes, multiorgan failure developed. Unfortunately, the patient died. Repeated abdominopelvic CT imaging revealed the progression of the disease to necrotizing pancreatitis involving the pancreatic head, uncinate process, and neck of the pancreas with evidence of a small hypodense lesion at the level of the tail of the pancreas. This case emphasizes the importance of prompt recognition of acute pancreatitis secondary to uncontrolled hyperglycemia with concomitant severe hypertriglyceridemia since it can lead to a worse clinical outcome as seen in our patient who developed rapid progression to necrotizing pancreatitis. It is paramount not to delay treatment with aggressive fluid resuscitation, continuous insulin infusion, and if available, plasmapheresis; as these treatment strategies in conjunction can be life-saving. Presentation: 6/3/2024

7085 Myoclonus Seizure with Pseudo-Adrenal Insufficiency as the Clinical Manifestations Leading to the Diagnosed Multi-focal Insulinomas that Mimic Multiple Endocrine Neoplasia Type 1 Syndrome

Abstract Disclosure: P. Kiatpanabhikul: None. Background: Insulinoma is a rare disease that presents with varying symptoms and can be sporadic or associated with hereditary syndromes (1). These rare points of views of insulinoma-patient on clinical manifestations, hormonal responses and surgical pathology result for final diagnosis and management. Clinical Case: A 59-year-old woman presented with myoclonic seizure of right arm with consciousness duration 5-10 minutes every midday twice a week for 6 months and generalized convulsion for 20 minutes ago. She had a low FPG level (59 mg/dL; n 70-100) and was admitted to doing 72-hour fasting test that revealed hypoglycemia at 12-hour of fasting with a nadir glucose level of 55 mg/dL, insulin 3.7 uIU/mL (cutoff > 5), C-peptide 0.4 ng/mL (cutoff > 0.6), cortisol 6.22 mcg/dL (n 5-25) and normal morning ACTH level (29.8 pg/mL; n 10-65). These were appropriated response of endogenous insulinemia with inappropriate response of serum cortisol level in hypoglycemic feature. MRI pituitary gland was considered to evaluate secondary hypocortisolism which showed a small less enhancing lesion left anterior lobe 0.3x0.45-cm without any pituitary hormonal abnormalities that were considered non-functioning pituitary microadenoma which could not explain inappropriate response of cortisol level to hypoglycemic period in this patient. Five months later, she presented at the emergency room with myoclonic seizure on her extremities, blurred consciousness and slurred speech after having lunch for 1-2 hour and revealed CPG 30 mg%, severe hypoglycemia (26 mg/dL), hypocortisolism (4.49 mcg/dL), with endogenous hyperinsulinemia (insulin 55.2 uIU/mL, C-peptide 2.5 ng/mL). 250-mcg ACTH stimulation test was done and showed normal response of her HPA-axis function (serum cortisol level at 0, 30, 60 min was 9.12, 17.87, 18.61 mcg/dL). CT pancreatic protocol showed several arterial enhancing nodules scattering at pancreatic tails isoattenuation to pancreatic parenchyma on portovenous phase up to 1.7*1.6 cm. She was operated on to distal pancreatectomy with intraoperative insulin/glucose ratio monitoring. Surgical pathology confirmed 4-well-differentiated pancreatic neuroendocrine tumors with insulin-producing, sizes 0.5-1.7 cm in diameter. Her final diagnosis was multi-focal insulinomas with non-functioning pituitary microadenoma that mimic MEN-1 syndrome without secondary adrenal insufficiency. She underwent successful surgical resection with complete resolution of symptoms during 4 years of followed-up with no recurrence and no having any hypercalcemia and hyperprolactinemia. Conclusion: Multi-focal insulinomas can be presented as sporadic, more severe hypoglycemia and endogenous hyperinsulinemia during period after meal with myoclonic seizure and pseudo-adrenal insufficiency in older-aged, non-diabetes person without recurrence after treatment for 4-year of followed-up. Presentation: 6/2/2024

7202 CPP with Rapid Pubertal Progression in a 9-Year-Old Boy with Hypothalamic Teratoma

Abstract Disclosure: R. Robilliard: None. G. Tung: None. K. Svokos: None. R. Lulla: None. J.Q. Quintos: None. Background: Central Precocious Puberty (CPP) in males is rare, with incidence of 0.01-2/10,000. The most common identifiable cause of CPP in young children is hypothalamic hamartoma. No case hypothalamic teratoma has been reported to cause CPP in males. Clinical Case: At the age of 10-years and 5-months, a boy presented to the pediatric endocrinology with signs of precocious puberty including facial hair development, voice deepening, and increased growth velocity that began at 9 years old. There was no significant past medical history and he denied headache, blurry vision, or diplopia. Physical examination showed height of 140.4 cm (47%), Tanner 4 genitalia, Tanner 3 pubic hair, and testicular volumes of 15 cc (left) and 12-15cc (right). Bone age (BA) determined by radiography was 13.5 years with a predicted adult height (PAH) of 63 inches. The mid-parental target height was 67 +/- 4 inches. Evaluation including TSH, glucose, serum and CSF β-HCG, DHEA, CSF AFP was normal. Serum LH was 2.9 IU/L and testosterone level was 109 ng/dl, consistent with CPP. MRI of the pituitary showed a small, heterogeneous and fat-containing lesion extending inferiorly from the tuber cinereum consistent with teratoma. Treatment included GnRH agonist Lupron (30mg) every 3 months. Laboratory evaluation 8 months after initial presentation showed suppressed LH of 0.9 IU/L and FSH 0.5 mIU/mL, and testosterone of 57 ng/dL. Repeat radiography for BA one year after GnRHa suppression showed BA of 14 years at CA of 11 years 6 months and PAH of 64.4 inches. Growth velocity slowed to 5.3 cm/year. At the most recent follow-up visit at CA of 12 years, height was 151.5 cm (61%), growth velocity 6.3 cm/year (74% for age), Tanner 5 penis and pubic hair, left testicular volume of 15-20cc and right testicular volume of 15 cc. Most recent radiographic BA is14 years, and PAH is 65.9 inches. Given response to GnRH agonist injections every 3 months, the absence of CNS symptoms referable to the teratoma and no change in MR imaging, no surgical intervention is recommended. Conclusion: This is the first case of a hypothalamic teratoma reported in a male associated with CPP. Despite this rare cause, the patient has responded to standard treatment with GnRH agonist therapy alone. Presentation: 6/1/2024

6419 Cushing’s Syndrome due to Metastatic Pancreatic Neuroendocrine Neoplasm With Incidental Pituitary Microadenoma

Abstract Disclosure: A. Ibrahim: None. L. Esper: None. R. Jain: None. N. El Asmar: None. Introduction: Pancreatic neuroendocrine neoplasms (PNENs) are rare with a reported incidence of 1-2/100,000. While the majority are non-functional, insulinomas and gastrinomas are the most common functional PNENs. Our case of ACTH-producing PNENs is extremely rare. Case presentation: A previously healthy 47-year-old female was hospitalized for worsening dyspnea. Her symptoms included rapid weight gain, skin hyperpigmentation, and lower extremity edema. Her exam was notable for elevated blood pressure of 181/120 mmHg, moon facies, purple abdominal striae, and proximal myopathy. Her lab analysis showed a cortisol level of 42 mcg/dL (6.2-19.4), ACTH of 254 pg/ml (7.2-63), DHEA sulfate of 171 mcg/dl (41-243), HbA1C 7%, K of 3 mmol/l and 24H urine cortisol >2100 mcg/24hrs. A post low-dose DST cortisol level was 42.7 mcg/dl. CT chest demonstrated an ill-defined hypodense lesion in the region of the pancreatic head. MRI abdomen revealed a 3 x 2.3 x 2.3 cm mass in the pancreatic head and many small enhancing lesions within the right lobe of the liver. Adrenal glands appeared normal. Subsequent PET CT scan with GA 68 DOTOTATE showed increased uptake in the pancreatic head mass and in the right hepatic lobe. Her pituitary MRI revealed a right pituitary gland 6 mm hypointense lesion, possibly a microadenoma. A high dose DST resulted in a cortisol level of 80 mcg/dl mostly consistent with ectopic ACTH secretion. EUS-guided biopsy of the pancreatic mass showed a well-differentiated neuroendocrine tumor that stained positive for ACTH, chromogranin, synaptophysin, and CD56. Treatment with Ketoconazole 600mg q6h and Octreotide 50mg q6h was started 3 days before surgery to control acute hypercortisolism as she developed acute psychosis. The patient subsequently underwent a Whipple procedure with successful resection of the pancreatic mass. Post-op, her ACTH levels dropped to 19 pg/ml with a cortisol level of 6 mcg/dl. Final pathology showed a well-differentiated grade 3 neuroendocrine tumor with a KI-67 labeling index greater than 20%. After surgery, the patient received a short course of stress dose hydrocortisone which was tapered off over the following 2 months. The patient is being followed for planning further intervention given the aggressive grade of the tumor and hepatic metastases. Conclusion: Ectopic ACTH-producing PNENs are rare. An accurate and timely diagnosis, while challenging, is key. Patients usually present with rapidly progressing symptoms that could cause life-threatening complications such as thrombosis and sepsis. We demonstrated the importance of utilizing a multidisciplinary team approach and starting cortisol-lowering medications early given the complexity of the disease, requiring rapid intervention and lifelong follow-up. Presentation: 6/3/2024

7642 A Mixed Model of Clinical Characteristics and Ultrasound ACR-TIRADS Predicts Malignancy in Thyroid Micro Lesions

Abstract Disclosure: N. Angelopoulos: None. I. Iakovou: None. D. Goulis: None. R. Paparodis: None. S. Livadas: None. A. Boniakos: None. J.C. Jaume: None. Background: The frequency of papillary thyroid carcinoma (PTC) has increased, mainly due to the detection of small tumors incidentally found during unrelated imaging. While most of these small cancers have a non-aggressive course, some can be more biologically hostile, with potential for metastasis. Current guidelines discourage routine biopsy for nodules ≤10 mm, but the challenge is identifying higher-risk microcarcinomas. This study aims to identify ultrasound and clinical characteristics indicating malignancy in small thyroid lesions. Patients and methods: 151 patients with accidentally discovered solid nodules in thyroid ultrasound were enrolled in the study. All patients were stratified according to both ACR and EU-TIRADS systems. Two qualified endocrinologists performed ACR-TIRADS scoring and accordingly, all patients were stratified to the five ACR categories TR1-5 Strain elastography was also performed in all nodules and the elastography ratio (E2/E1) was calculated (E2 elastography of the nodule, E1 elastography of healthy thyroid gland). FNA was performed in nodules classified as EU-TIRADS 5 Results: 41 patients were classified as EU-TIRADS 5. The rest of the patients were classified as 69 EU-TIRADS 4, 40 EU-TIRADS 3, and one EU-TIRADS 2. According to FNA results, 11 patients had Bethesda II cytology (Group A), 2 Bethesda III, one Bethesda IV, 10 Bethesda V, and 17 Bethesda VI (V and VI comprised Group B). FNAs indicative of malignancy (Group B) were more frequent in patients with autoimmune thyroiditis (Chi-squared 5,833, df(1), p=0.015). In Group B, both ACR-scoring points and ACR-TIRADS categories were significantly higher than those detected in patients in Group A. Logistic regression analysis revealed a significant prognostic role of ACR-scoring points in discriminating suspicious FNA results for thyroid cancer. ROC analysis (AUC:0.993 with Youden Index:0.926, associated criterion >6, Sensitivity 92.59 % and Specificity 100 %). To analyze the predictive power of the clinical parameters in the presence of thyroid malignancy, age, BMI, gender, autoimmune disease, therapy, nodule diameter, and elastography ratio were examined in a “clinical model”. The overall prognostic value of the model was significant (p=0.0029, AUC:0.744) with a sensitivity of 77.78% and specificity of 72.73%, (Youden Index: 0.505, associated criterion >0.6). Finally, a “mixed model”, combining the clinical characteristics and the ACR scoring points, was generated for methodological reasons. The model was overall significant (p<0.001) with AUC:1 (95% Confidence interval: 0.907 to 1), Youden Index:1, sensitivity, and specificity 100%. Conclusion: ACR- TIRADS points > 6 may be a strong indicator of thyroid malignancy and the “mixed model” is an excellent predictor of thyroid malignancy, but its usefulness in everyday clinical practice may be cumbersome. Presentation: 6/1/2024

6728 Bilateral Adrenal Hemorrhage: Cause Or Consequence?

Abstract Disclosure: M.N. Rayan: None. R. Horner: None. A. Valenciaga: None. L.E. Ryan: None. Introduction: Before the advent of the CT scan, bilateral adrenal hemorrhage was primarily discovered post-mortem in patients who had succumbed to sepsis, burns, or anticoagulant therapy. Today, non-traumatic hemorrhage is recognized as an infrequent, yet potentially lethal diagnosis causing clinical deterioration in acutely ill patients. Clinical Case: Our patient is a 64-year-old-male with a medical history of Myelodysplastic Syndrome initially presented to an external ED with abdominal pain. CT abdomen revealed hepatomegaly, splenomegaly, and new bilateral adrenal masses—absent in an MRI conducted a year earlier. He was treated conservatively and subsequently discharged. Two weeks later, he returned to the hospital with severe right sided flank pain. His hemoglobin and platelet counts dropped from 11.5 g/dL and 309 K/uL during the previous ED visit to 7.7 g/dL and 80 K/uL, respectively. Additionally, his PT/INR, PTT, fibrinogen, and D-Dimer levels were elevated. A repeat CT scan indicated a significant enlargement of the right adrenal mass, raising suspicion of adrenal hemorrhage. He was appropriately transfused, and a BM biopsy was performed to evaluate for acute transformation of underlying MDS. Cortisol levels were monitored daily for adrenal insufficiency. A complicated hospital course ensued marked by worsening anemia, thrombocytopenia, and coagulopathy, accompanied by high fevers and new-onset atrial fibrillation. Mixing studies showed absence of a factor inhibitor ruling out acquired forms of Hemophilia. Infectious workup including fungal and viral serologies returned negative. A PET scan revealed several small hypermetabolic hypodense liver lesions, and hypermetabolic activity diffusely in the spleen, and adrenal glands leading to suspicion of metastasis. Results of the BM biopsy returned revealing hypercellularity, with aggregates of hemosiderin-laden macrophages replacing the bone marrow space with associated necrosis. Worsening abdominal pain with hematochezia prompted an endoscopy, confirming a diagnosis of metastatic melanoma. Concurrently, seizure activity and altered mentation led to a head CT, revealing new metastatic lesions that confirmed the rapid progression of the disease. Subsequently, the patient was transitioned to comfort care and passed away. Clinical Lesson: It is crucial to review the various causes of adrenal hemorrhage, understand the challenges associated with interpreting adrenal imaging, emphasize the need to monitor adrenal function, and consider the occasional necessity for tissue sampling. In this clinical scenario, metastases with hemorrhage were the most likely etiology. The causes of adrenal hemorrhage are not always apparent; in this presentation, the consequence of the underlying disease state ultimately led to the initial presenting symptom of abdominal pain. Presentation: 6/2/2024

7254 An Unusual Case Of Hypercalcemia

Abstract Disclosure: S. Shushtarian: None. M. Balogun: None. T. Kaur: None. Hypercalcemia varies depending on severity. Higher serum calcium levels and more severe symptoms may indicate primary hyperparathyroidism or a malignant cancer. This is a case of a 32 year old female who presented with recurrent history of nephrolithiasis, found to have hypercalcemia of 13.4 mg/dL and parathyroid hormone of 1928.9 pg/mL, with phosphorus of 1.5 mg/dL. Ultrasound of her thyroid revealed a complex nodule arising from the right parathyroid gland measuring 2.2 X 2.0 cm. CT chest revealed diffuse osseous sclerosis secondary to metabolic disorder. Sestamibi scan did not localize any parathyroid adenoma. MRI of the thoracic and lumbar spine showed multiple small enhancing lesions throughout the pelvis and in the left rib, likely brown tumors related to hyperparathyroidism. X-ray of bony prominence on the patient’s left knee revealed a large lytic lesion of the proximal tibial diaphysis measuring 5.1 X 1.9 cm, concerning for aggressive neoplasm. Subsequent left tibial bone biopsy revealed giant cell rich lesions consistent with brown tumor of hyperparathyroidism. Due to our patient’s high calcium levels and large nodule size, she was referred to a tertiary center as the concern for parathyroid carcinoma and post-op hungry bone syndrome was high. Pre-op PTH level was 1408 pg/mL and post-op PTH was 96 pg/mL. The tumor removed was 2.1 cm. Post surgical pathology was consistent with atypical parathyroid adenoma. Patient was referred for genetic testing. An atypical parathyroid adenoma (APA) only accounts for 1.2 to 1.3% of cases of primary hyperparathyroidism. 80-85% of primary hyperparathyroidism is due to typical adenoma, and 10 to 15% of cases are due to hyperplasia or multiple gland disease. APA can often be confused with parathyroid carcinoma (PC), as they both have a 1:1 male to female ratio, high serum calcium levels, symptomatic hypercalcemia, high PTH levels, and fragility fractures. There are studies showing that both APA and PC have loss of nuclear parafibromin immunoreactivity. In addition, neither APA nor PC have any correlation with menopause, hormones, or gene deletions, unlike typical adenomas. Biopsy is necessary for diagnosis as the histological and immunohistochemical differences can differentiate APA vs PC. Histological features include pseudo-capsular invasion, bands of fibrosis, pronounced trabecular growth, nuclear atypia, and prominent nucleoli. Also, APA has a strong membranous staining pattern of E-cadherin, whereas PC has a loss of membranous staining. These differences are essential as although APA and PC clinically present similarly, APA lacks the invasive growth and possibility for metastatic disease that PC has. The likelihood for relapse of APA is low. Presence of malignancy criteria are indicative that a mass is actually PC and not APA. Despite this, APA is still considered a tumor of uncertain malignant potential and requires follow up. Presentation: 6/3/2024

Giant serous cystadenomas encountered in clinical practice: A case series

Benign serous cystadenomas represent 16% of all ovarian epithelial neoplasms, and account for up to two-thirds of epithelial tumors of the ovary. They are commonly encountered after the 3rd decade of life and in the later decades, due to the slow growth nature over lifetime. These tumors may begin as small unilocular subcentimeter lesions, but may expand to fill the entire abdominal cavity. This may present with mass effect to surrounding tissues and organs, and lead to sequela of compartment syndrome of the peritoneal cavity. We present a case series of surgical evaluation and management of extremely enlarged serous cystadenomas of the ovary (>30 cm) encountered in an atypical age presentation, with the first case involving a 19 year old who had a known 6 cm cyst four years prior, who presented to emergency room (ER) with gastrointestinal (GI) symptoms secondary to the tumors mass effect, imaging demonstrating a massive tumor, subsequently requiring surgical dissection. The second case demonstrates a 25 year old with known cyst (>20 cm) two years prior who presented with even larger effect (close to 40 cm size) and worsening symptoms due to the tumors mass effect requiring removal. In both cases, patients presented to emergency room with acute symptoms, exploratory laparotomy was required for complete evacuation of lesion and for resolution of symptoms.

Evaluating the persistence of large choroidal hypertransmission defects using SS-OCT imaging

In age-related macular degeneration (AMD), large choroidal hypertransmission defects (hyperTDs) are identified on en face optical coherence tomography (OCT) images as bright lesions measuring at least 250 μm in greatest linear dimension (GLD). These choroidal hyperTDs arise from focal attenuation or loss of the retinal pigment epithelium (RPE). We previously reported that once large hyperTDs formed, they were likely to persist compared with smaller lesions that were more likely to be transient. Due to their relative persistence, these large persistent choroidal hyperTDs are a point-of-no-return in the progression of intermediate AMD to the late stage of atrophic AMD. Moreover, the onset of these large choroidal hyperTDs can serve as a clinical trial endpoint when studying therapies that might slow disease progression from intermediate AMD to late atrophic AMD. To confirm the persistence of these large choroidal hyperTDs, we studied an independent dataset of AMD eyes enrolled in an ongoing prospective swept-source OCT (SS-OCT) natural history study to determine their overall persistence. We identified a total of 202 eyes with large choroidal hyperTDs containing 1725 hyperTDs followed for an average of 46.6 months. Of the 1725 large hyperTDs, we found that 1718 (99.6%) persisted while only 7 hyperTDs (0.4%) were non-persistent. Of the 7 non-persistent large hyperTDs in 6 eyes, their average GLD at baseline was 385 μm. Of the large hyperTDs ranging in size between 250 and 300 μm when first detected, only one was not persistent with a baseline GLD of 283 μm. In 6 of the non-persistent hyperTDs, the loss of a detectable large hyperTD was due to the accumulation of hyperreflective material along the retinal pigment epithelium (RPE) and in the retina over the area where the hyperTD was located. This hyperreflective material is thought to represent the migration and aggregation of RPE cells into this focal region where the choroidal hyperTD arose due to attenuated or lost RPE.

A weighted and cumulative point system for accurate scoring of intestinal pathology in a piglet model of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a serious condition in premature infants, in which a portion of the intestine undergoes inflammation and necrosis. The preterm pig develops NEC spontaneously, making it a suitable model for exploring novel NEC treatments. We aimed to revise the intestinal scoring system to more accurately describe the diversity of NEC lesions in the preterm piglet model. We included 333 preterm piglets from four experiments, each delivered via cesarean section. The piglets were fed either a gently processed (GP) or harshly processed (HP) milk formula for 96 h before euthanasia. At necropsy, the gastrointestinal tract was assessed with 1) an established 6-grade score and 2) a descriptive approach focusing on the distribution and severity of hyperemia, hemorrhage, pneumatosis intestinalis (intramural gas), and necrosis. Subsequently, the descriptive registrations were converted into a weighted and cumulative point (WCP) score. Compared to the 6-grade score, the WCP score enabled a greater segregation of severity levels, especially among organs with more prominent NEC lesions. IL-1β in small intestinal lesions and both IL-8 and IL-1β in colon lesions correlated positively with the WCP scale. A histopathological grade system (0–8) was established and revealed mucosal pathology in lesion biopsies, which were not recognized macroscopically. Finally, the WCP score showed a higher NEC-promoting effect of the HP formula compared to the GP formula. The descriptive registrations and extended score range of this revised intestinal scoring system enhance the accuracy of describing NEC lesions in preterm pigs. This approach may increase the efficiency of preclinical NEC experiments.

DSA Quantitative Analysis and Predictive Modeling of Obliteration in Cerebral AVM following Stereotactic Radiosurgery.

Stereotactic radiosurgery is a key treatment modality for cerebral AVMs, particularly for small lesions and those located in eloquent brain regions. Predicting obliteration remains challenging due to evolving treatment paradigms and complex AVM presentations. With digital subtraction angiography (DSA) being the gold standard for outcome evaluation, radiomic approaches offer potential for more objective and detailed analysis. We aimed to develop machine learning modeling using DSA quantitative features for post-SRS obliteration prediction. A prospective registry of patients with cerebral AVMs was screened to include patients with digital prestereotactic radiosurgery DSA. Anterior-posterior and lateral views were retrieved and manually segmented. Quantitative features were computed from the lesion ROI. Following feature selection, machine learning models were developed to predict unsuccessful 2-year total obliteration using processed radiomics features in comparison with clinical and radiosurgical features. When we evaluated through area under the receiver operating characteristic curve (AUROC), accuracy, area under the precision-recall curve F1, recall, and precision, the best performing model predictions on the test set were interpreted using the Shapley additive explanations approach. DSA images of 100 included patients were retrieved and analyzed. The best-performing clinical radiosurgical model was a gradient boosting classifier with an AUROC of 68% and a recall of 67%. When we used radiomics variables as input, the AdaBoost classifier had the best evaluation metrics with an AUROC of 79% and a recall of 75%. The most important clinico-radiosurgical features, ranked by model contribution, were lesion volume, patient age, treatment dose rate, the presence of seizure at presentation, and prior resection. The most important ranked radiomics features were the following: gray-level size zone matrix, gray-level nonuniformity, kurtosis, sphericity, skewness, and gray-level dependence matrix dependence nonuniformity. The combination of radiomics with machine learning is a promising approach for predicting cerebral AVM obliteration status following stereotactic radiosurgery. DSA could enhance prognostication of stereotactic radiosurgery-treated AVMs due to its high spatial resolution. Model interpretation is essential for building transparent models and establishing clinically valid radiomic signatures.

Detectability of Hypoattenuating Liver Lesions with Deep Learning CT Reconstruction: A Phantom and Patient Study.

Background CT deep learning image reconstruction (DLIR) improves image quality by reducing noise compared with adaptive statistical iterative reconstruction-V (ASIR-V). However, objective assessment of low-contrast lesion detectability is lacking. Purpose To investigate low-contrast detectability of hypoattenuating liver lesions on CT scans reconstructed with DLIR compared with CT scans reconstructed with ASIR-V in a patient and a phantom study. Materials and Methods This single-center retrospective study included patients undergoing portal venous phase abdominal CT between February and May 2021 and a low-contrast-resolution phantom scanned with the same protocol. Four reconstructions (ASIR-V at 40% strength [ASIR-V 40] and DLIR at three strengths) were generated. Five radiologists qualitatively assessed the images using the five-point Likert scale for image quality, lesion diagnostic confidence, conspicuity, and small lesion (≤1 cm) visibility. Up to two key lesions per patient, confirmed at histopathologic testing or at prior or follow-up imaging studies, were included. Lesion-to-background contrast-to-noise ratio was calculated. Interreader variability was analyzed. Intergroup qualitative and quantitative metrics were compared between DLIR and ASIR-V 40 using proportional odds logistic regression models. Results Eighty-six liver lesions (mean size, 15 mm ± 9.5 [SD]) in 50 patients (median age, 62 years [IQR, 57-73 years]; 27 [54%] female patients) were included. Differences were not detected for various qualitative low-contrast detectability metrics between ASIR-V 40 and DLIR (P > .05). Quantitatively, medium-strength DLIR and high-strength DLIR yielded higher lesion-to-background contrast-to-noise ratios than ASIR-V 40 (medium-strength DLIR vs ASIR-V 40: odds ratio [OR], 1.96 [95% CI: 1.65, 2.33]; high-strength DLIR vs ASIR-V 40: OR, 5.36 [95% CI: 3.68, 7.82]; P < .001). Low-contrast lesion attenuation was reduced by 2.8-3.6 HU with DLIR. Interreader agreement was moderate to very good for the qualitative metrics. Subgroup analysis based on lesion size of larger than 1 cm and 1 cm or smaller yielded similar results (P > .05). Qualitatively, phantom study results were similar to those in patients (P > .05). Conclusion The detectability of low-contrast liver lesions was similar on CT scans reconstructed with low-, medium-, and high-strength DLIR and ASIR-V 40 in both patient and phantom studies. Lesion-to-background contrast-to-noise ratios were higher for DLIR medium- and high-strength reconstructions compared with ASIR-V 40. © RSNA, 2024 Supplemental material is available for this article.

Comparison of Clinical Outcomes between Drug-Eluting Balloons and Drug-Eluting Stents in Patients with Small Coronary Artery Disease

Background/Aims: Drug-eluting balloons (DEBs) represent a novel therapeutic approach for patients with small coronary artery disease. However, further studies are needed to compare the clinical efficacy of DEBs versus drug-eluting stents (DESs).Methods: In total, 492 patients (age, 67.9 ± 11.0 years; 339 men) with small coronary artery lesions (diameter &lt; 2.75 mm) were randomly assigned to group I (DEB) (n = 104; age, 67.2 ± 10.7 years; 83 men) and group II (DES) (n = 388; age, 68.0 ± 11.1 years; 254 men). For inverse probability of treatment weighting (IPTW) analysis, the study population was stratified into groups I (n = 269) and II (n = 280). We compared the incidences of major adverse cardiac events (MACE) between the two groups during 12 months of clinical follow-up.Results: Group I had shorter device lengths (22.4 ± 5.8 mm) compared with group II (27.4 ± 9.3 mm; p &lt; 0.001). Additionally, devices in group I were smaller in diameter (2.4 ± 0.1 mm) compared with those in group II (2.6 ± 0.1 mm; p &lt; 0.001). Left ventricular ejection fraction (LVEF) was lower in group I (53.8% ± 12.6%) than in group II (58.6% ± 11.9%; p &lt; 0.001). After IPTW, no significant differences in LVEF were observed between groups I and II. During 12 months of follow-up, the incidence of total MACE did not differ between the two groups.Conclusions: No significant differences were observed in clinical efficacy between DEB and DES for the treatment of small coronary artery disease. Therefore, DEB can be considered a viable alternative to DES in patients with small coronary artery disease.

Accelerated Cartesian cardiac T2 mapping based on a calibrationless locally low-rank tensor constraint.

Cardiac T2 mapping is a valuable tool for diagnosing myocardial edema, inflammation, and infiltration, yet its spatial resolution is limited by the single-shot balanced steady-state free precession acquisition and duration of the cardiac quiescent period, which may reduce sensitivity in detecting focal lesions in the myocardium. To improve spatial resolution without extending the acquisition window, this study examined a novel accelerated Cartesian cardiac T2 mapping technique. We introduce a novel improved-resolution cardiac T2 mapping approach leveraging a calibrationless space-contrast-coil locally low-rank tensor (SCC-LLRT)-constrained reconstruction algorithm in conjunction with Cartesian undersampling trajectory. The method was validated with phantom imaging and in vivo imaging that involved 13 healthy participants and 20 patients. The SCC-LLRT algorithm was compared with a conventional locally low-rank (LLR)-constrained algorithm and a nonlinear inversion (NLINV) reconstruction algorithm. The improved-resolution T2 mapping (1.4 mm × 1.4 mm) was compared globally and regionally with the regular-resolution T2 mapping (2.3 mm × 1.9 mm) according to the 16-segment model of the American Heart Association. The agreement between the improved-resolution and regular-resolution T2 mappings was evaluated by linear regression and Bland-Altman analyses. Image quality was scored by two experienced reviewers on a five-point scale (1, worst; 5, best). In healthy participants, SCC-LLRT significantly reduced artifacts (4.50±0.39) compared with LLR (2.31±0.60; P<0.001) and NLINV (3.65±0.56; P<0.01), suppressed noise (4.12±0.35) compared with NLINV (2.65±0.50; P<0.001), and improved the overall image quality (4.38±0.40) compared with LLR (2.54±0.41; P<0.001) and NLINV (3.04±0.50; P<0.001). Compared with the regular-resolution T2 mapping, the proposed method significantly improved the sharpness of myocardial boundaries (4.46±0.60 vs. 3.04±0.50; P<0.001) and the conspicuity of papillary muscles and fine structures (4.46±0.63 vs. 2.65±0.30; P<0.001). Myocardial T2 values obtained with the proposed method correlated significantly with those from regular-resolution T2 mapping in both healthy participants (r=0.79; P<0.01) and patients (r=0.94; P<0.001). The proposed SCC-LLRT-constrained reconstruction algorithm in conjunction with Cartesian undersampling pattern achieved improved-resolution cardiac T2 mapping of comparable accuracy, precision, and scan-rescan reproducibility compared with the regular-resolution T2 mapping. The higher resolution improved the sharpness of myocardial borders and the conspicuity of image fine details, which may increase diagnostic confidence in cardiac T2 mapping for detecting small lesions.

Damage to the host cadaver, simulating the effects of scavenging, differentially affects fitness of entomopathogenic nematode species

Insect cadavers infected by entomopathogenic nematodes (EPN) are defended against scavengers by chemical and other means. Despite these defences, the cadaver may be bitten before being rejected. In this study, we investigated the effect of damage to the cadaver cuticle on the fitness of nematodes (Heterorhabditis downesi or Steinernema feltiae) developing inside. We first quantified the severity of scavenger damage to EPN-infected Galleria mellonella Linnaeus cadavers in the field, and separately, with crickets (Gryllus bimaculatus De Geer) in the laboratory. In field and laboratory, EPN-infected cadavers suffered less damage than freeze-killed controls, and damage consisted mainly of small lesions to the cuticle. In further experiments, scavenging damage was simulated shortly after death of infected cadavers by piercing the cuticle 0, 1, 3 or 5 times and incubating in moist (100% relative humidity (RH)) or dry (60-70% RH) conditions. The greater the level of damage, the greater the loss of moisture from the cadaver (estimated by weight loss), and this was exacerbated in dry conditions. The number of Infective Juveniles (IJs) emerging from H. downesi-infected cadavers was significantly reduced by damage, especially in dry conditions. In addition, emerging IJs were progressively smaller with increasing damage. For this species, number of IJs was negatively correlated with moisture loss, indicated that the reduction in fitness was mediated by desiccation. For S. feltiae, damage impacted IJ number to a lesser extent and size was not affected. The reduction in numbers was not explained by moisture loss, indicating that for S. feltiae, some factor other than desiccation (perhaps competition with opportunistic microbes) impacts the nematodes when the cuticle is damaged. The greater vulnerability of H. downesi than S. feltiae to scavenger damage to the host cadaver may be due to its longer developmental time in the host resulting in longer exposure to damaging conditions. In conclusion, damage simulating biting by scavengers impacts the fitness of EPN, with the effect depending on nematode species, environmental conditions and the extent of damage. These findings have implications for the success of field application of EPN in infected cadavers.

UTILITY OF CONTRAST-ENHANCED T2-FLAIR FOR IMAGING OF BRAIN METASTASESUSING A HALF-DOSE HIGH-RELAXIVITY CONTRAST AGENT IN COMPARISON WITH ROUTINE DOSE CONTRAST-ENHANCED BRAIN IMAGING

Aim &amp; Objectives: This study aims to assess the efficacy of delayed contrast-enhanced T2 fluid-attenuated inversion recovery (CE-T2 FLAIR) by using half dose high relaxivity contrast agent to assess the degree of enhancement among the lesions and to detect additional metastatic brain lesions usually smaller lesions(&lt;5mm), which are significantly missed on routine-dose CE-T1 weighted imaging (CE-T1WI). Material &amp; Methods:The main source of data for this study was radiologically diagnosed lung cancer patients who were clinically suspected to have brain metastasis referred from various departments of Silchar Medical College and Hospital. The studywas carried out for a period of 1 year from March 1, 2023, to February 29, 2024, A total of 40 patients with brain metastases were scanned using a SIEMENS TIM AVANTO 1.5T scanner, routine MR pulse sequences pre- and post-contrast administration were acquired. Results: Out of 40 patients, males were more affected (57.5 %) than females (42.5 %). The highest number of cases were found between the 61-70 years age group with the lung (31 cases) being the most common primary malignancy causing brain metastases. A total of 90 lesions were detected among 40 patients which were grouped into A (25 lesions), B (36 lesions), and C (29 lesions) groups. A total of 6 lesions were missed on Routine dose contrast-enhanced brain imaging of which 2 lesions belong to group B (Rim enhancing lesions &gt;5mm) and 4 lesions belong to group C (Lesions &lt;5mm), however, these lesions were picked up on delayed half dose contrast-enhanced FLAIR images. The contrast ratio (CR) on 3 consecutive half dose CE-T2 FLAIR ranged between 59.09%-76.80%, suggesting that delay in imaging post-contrast administration resulted in a significant increase in the contrast ratio (CR) among metastatic lesions. Conclusions: CE-T1-weighted sequences and CE-T2 FLAIR sequences complement each other effectively in evaluating brain metastases. Bigger and homogenously enhancing lesions are best seen on CE-T1-weighted sequences. Smaller lesions and lesions showing rim enhancement are best visualized on delayed (5 min) CE-T2 fluid-attenuated inversion recovery (FLAIR) sequences with half the dose ofcontrast agent (gadobenatedimeglumine) compared to routine dose CE-T1-weighted sequences. This approach serves as a cost-saving measure for both patients and the healthcare system.

Ectopic and transient expression of VvDIR4 gene in Arabidopsis and grapes enhances resistance to anthracnose via affecting hormone signaling pathways and lignin production.

DIR (Dirigent) proteins play important roles in the biosynthesis of lignin and lignans and are involved in various processes such as plant growth, development, and stress responses. However, there is less information about VvDIR proteins in grapevine (Vitis vinifera L). In this study, we used bioinformatics methods to identify members of the DIR gene family in grapevine and identified 18 VvDIR genes in grapevine. These genes were classified into 5 subfamilies based on phylogenetic analysis. In promoter analysis, various plant hormones, stress, and light-responsive cis-elements were detected. Expression profiling of all genes following Colletotrichum gloeosporioides infection and phytohormones (salicylic acid (SA) and jasmonic acid (JA)) application suggested significant upregulation of 17 and 6 VvDIR genes, respectively. Further, we overexpressed the VvDIR4 gene in Arabidopsis thaliana and grapes for functional analysis. Ectopic expression of VvDIR4 in A. thaliana and transient expression in grapes increased resistance against C. gloeosporioides and C. higginsianum, respectively. Phenotypic observations showed small disease lesions in transgenic plants. Further, the expression patterns of genes having presumed roles in SA and JA signaling pathways were also influenced. Lignin contents were measured before and after C. higginsianum infection; the transgenic A. thaliana lines showed higher lignin content than wild-type, and a significant increase was observed after C. higginsianum infection. Based on the findings, we surmise that VvDIR4 is involved in hormonal and lignin synthesis pathways which regulate resistance against anthracnose. Our study provides novel insights into the function of VvDIR genes and new candidate genes for grapevine disease resistance breeding programs.

Diagnostic performance of simultaneous PET-magnetic resonance versus PET-computed tomography in oncology with an overview on clinical utility and referral pattern of PET-magnetic resonance: a single institutional study.

PET-magnetic resonance (PETMR) imaging is an upcoming investigative modality with a few installations in Asia and only three in India. PET-Computed tomography (PETCT) is an established diagnostic cornerstone for oncological indications but with limited resolution for small lesions due to low soft-tissue contrast and additional radiation exposure. Our primary objective was to evaluate the diagnostic performance of simultaneous PETMR and PETCT in lesion detection in oncological practice. Secondly to assess the referral pattern and study the clinical utility of PETMR in a university hospital practice. A total of 100 consecutive biopsy-proven cancer patients (breast or lung malignancy with suspected metastases) underwent 18F fluorodeoxyglucose (FDG) PETMR and PETCT for staging as a single injection, double examination protocol. Morphological lesion detection on correlative imaging/histopathology was used as the gold standard. Analysing the referral pattern, a total of 9366 patients underwent simultaneous PETMR imaging for indications in the past 5 years since installation. 18F FDG PETMR detected 100% of primary tumours in breast/lung carcinoma (Ca) patients while PETCT was positive in 96%. Overall accuracy of nodal metastases detection for PETMR and PETCT was 96 and 88%, while for distant metastases the accuracy was 100 and 93%, respectively. FDG PETMR proved more sensitive and specific than PETCT for regional nodal (P = 0.011 and P < 0.001) and distant metastases detection (P = 0.017 and P < 0.001, respectively). Analysing the general referral pattern for PETMR, the majority were oncology referrals (66.5, 33.5%) when compared to nononcological indications. About 66.24% were FDG based, followed by Ga prostate-specific membrane antigen and dodecane tetraacetic acid. The general utility of PETMR was found incremental in better delineation of small lesions especially in head, neck, liver, brain and gynaecological malignancies. In our past 5 years of PETMR practice, we found that simultaneous PETMR is a highly recommended ideal imaging technique for oncological and nononcological indications. It has excellent diagnostic performance with high sensitivity, specificity and accuracy when compared to PETCT in tumour, nodal metastases staging in specific subgroup of breast and lung malignancy patients.

Colorectal Neuroendocrine Neoplasm Detection Rate During Colonoscopy: Results From Large-Scale Data of Colonoscopies in Japan.

This study investigated the detection rate of colorectal neuroendocrine neoplasms (NENs) using large-scale colonoscopy data. This cross-sectional analysis used large-scale data from a Japanese multicenter observational study of colonoscopies performed from 2010 to 2020. Among 82,005 colonoscopy cases, colorectal NENs were identified in 71 (67 of which were neuroendocrine tumors), with a detection rate of 0.087% (95% confidence interval: 0.069-0.109). Most were small rectal lesions, with only 4 >10 mm in size and 3 located in the colon. The detection rate of colorectal NENs during colonoscopy is substantially higher than expected.

Endoscopic Ultrasound and Intraductal Ultrasound in the Diagnosis of Biliary Tract Diseases: A Narrative Review.

Endoscopic ultrasound (EUS) and intraductal ultrasound (IDUS) play very important roles in the field of biliary tract disease. Because of their excellent spatial resolution, the detection of small lesions and T- or N-staging of tumors have become possible. Additionally, contrast-enhanced EUS and the new imaging technique of detective flow imaging are reported to be useful for differential diagnosis. Furthermore, EUS-guided tissue acquisition is used not only for pathological diagnosis but also to collect tissue samples for cancer genome profiling. This review provides an overview of diagnosis utilizing the features and techniques of EUS and IDUS.