Adrenal Computed Tomography Research Articles

Application value of adrenal venous sampling in the surgical treatment of primary aldosteronism.

The diagnosis of primary aldosteronism (PA) is critical for determining treatment strategies. The aim of the present study was to investigate the clinical value of preoperative adrenal venous sampling (AVS) for determining the benefit of PA surgery. Patients diagnosed with PA at Liaocheng People's Hospital (Liaocheng, China) between January 2015 and December 2020 were selected and divided into two groups: Group A underwent adrenal computed tomography (CT) only, whereas Group B underwent adrenal CT and successful AVS. Subsequently, the improvement rate of adrenal CT and adrenal CT + AVS in the treatment of PA was compared. A total of 164 patients were included, with an average age of 46.69±13.64 years. There were 62 patients in Group A and 102 in Group B. Among the patients diagnosed with unilateral lesions on adrenal CT scan, 82.61% of patients in group A and 87.72% in group B showed improvement; however, the difference was not significant (χ2=0.534, P=0.465). Among the patients diagnosed with bilateral lesions on adrenal CT images, 62.50% of patients in Group A and 91.11% of patients in Group B showed improvement (P=0.019). In conclusion, unilateral adrenal lesions detected by CT did not benefit significantly from surgical decision-making after AVS. AVS should be advised for all patients with bilateral adrenal PA who are willing to undergo adrenal surgery, which is conducive to correct lateral segmentation and improve treatment choices.

Validation of the modified CT criteria for identifying non-adenomas.

Although adrenal computed tomography (CT) percentage washout is a potentially powerful imaging technique for differentiating adrenal adenomas from non-adenomas, its application to non-adenomas can be problematic. Recently, modified criteria for diagnosing pheochromocytomas using adrenal CT were developed based on data from 199 patients with surgically proven pheochromocytomas and adenomas. However, these criteria have not been thoroughly validated. The purpose of this study was to validate the performance of the modified criteria for diagnosing non-adenomas including pheochromocytomas. The conventional and modified criteria were applied to 266 patients from two cohorts who had surgically proven lipid-poor adenomas (155/266, 58.3%) and non-adenomas (111/266, 41.7%) and underwent adrenal CT. Two radiologists calculated the attenuation on each dynamic phase and percentage washout of adrenal masses. The final assessments based on the conventional and modified criteria were categorized into adenomas or non-adenomas. The diagnostic performance of each criterion for diagnosing non-adenomas was evaluated using the area under the receiver operating characteristic curve (AUC). False negatives and positives were also compared. The AUC for the diagnosis of non-adenomas was 0.806 for conventional criteria and 0.858 for modified criteria (p = 0.047). The false-negative rate of conventional criteria for the diagnosis of non-adenomas was 29.7%. Use of modified criteria could have reduced the false-negative rate by to 7.2%. The false-positive rate increased from 9% to 21.3% when using the modified criteria. The utilization of modified criteria has the potential to identify additional non-adenomas that would otherwise be misdiagnosed as adenomas using conventional criteria alone.

Multiple radiologist review of adrenal CT still frequently misses lateralized surgical primary aldosteronism.

Patients with primary aldosteronism (PA) have increased morbidity and mortality compared to those with essential hypertension. Accurate detection of lateralized PA is important so that affected patients can receive potentially curative adrenalectomy. However, around 40% of patients with lateralized PA have "normal" adrenal glands on computed tomography (CT). Additional independent review of imaging has been shown to improve diagnostic accuracy in many areas of imaging. Therefore, the authors sought to establish if multi-reader re-assessment of previously reported normal CT scans would result in increased detection of surgically remediable disease. The authors found that re-assessment of CT imaging by one, two, or three additional radiologists (or a combination thereof) slightly increased the detection of lateralized disease, but these differences were not statistically significant (p>.05). Readers had low inter-observer agreement (kappa=0.17). If detection of a discrete nodule on CT was made a prerequisite for adrenal vein sampling (AVS), a second read by another reviewer would still result in an excess of missed cases (84.2%, 36.8%, and 65.8%, respectively, for each of the three independent reviewers). Therefore, a "normal" CT does not preclude the possibility of lateralized PA. Adrenal vein sampling should still be strongly considered wherever available and whenever surgery is considered for treatment of PA, irrespective of CT findings.

THU015 Unilateral Adrenal Hyperplasia Causing ACTH-independent Hypercortisolism

Abstract Disclosure: N. Mogar: None. M.A. McConnell : None. R. Yu: None. J.E. Weinreb: None. Background: Adrenal cortical hyperplasia is defined radiographically as a non-malignant growth or enlargement of the adrenal glands. Adrenal hyperplasia is most commonly bilateral, with unilateral adrenal hyperplasia occurring less frequently. Unilateral adrenal hyperplasia has been associated with primary hyperaldosteronism, and there are only a few case reports describing unilateral adrenal hyperplasia associated with ACTH-independent hypercortisolism. Clinical Case: A 56-year-old man with sleep apnea was incidentally found to have a 4.6 cm left adrenal nodule found on computed tomography (CT) chest imaging. Adrenal CT revealed a heterogeneous 4.6 x 3.3 x3.7 cm left adrenal mass with internal calcifications and a portion of the mass measuring 38 Houndsfield units (HU). His 8AM serum cortisol level was 19.80 mcg/dL (5-23 mcg/dL). No ACTH level was collected; however, a serum DHEA-S level was 55 mcg/dL (32-240 mcg/dL). After low dose dexamethasone suppression test (LDDS), the serum cortisol level was elevated at 2.3 mcg/dL (<1.8 mcg/dL). Repeat LDDS revealed a cortisol level of 2.9 mcg/dL. A 24-hour urine free cortisol level was 27.2 mcg/24h (4-50 mcg/24h). Testing for pheochromocytoma and hyperaldosteronism was negative. The patient had no historical or physical signs of Cushing’s syndrome and no signs of malignancy. Due to concerning features on adrenal CT imaging (tumor size >4 cm, internal calcifications, and HU >10), the patient underwent unilateral adrenalectomy. The patient did not receive intraoperative corticosteroids and remained normotensive post-operatively. However, his post-operative 8AM cortisol level was <0.2 mcg/dL (5-23 mcg/dL) on two separate occasions. He was discharged on a short course of hydrocortisone, with eventual recovery of his hypothalamic-pituitary-adrenal (HPA) axis. Pathology revealed a diagnosis of cortical adrenal hyperplasia. Conclusion: The presence of postoperative hypocortisolemia demonstrates that this patient had ACTH-independent hypercortisolism. This case report would be one of few describing the rare diagnosis of unilateral adrenal hyperplasia associated with ACTH-independent hypercortisolism and would add to the sparse literature currently available on this condition. Additionally, this case report highlights the clinical significance of mild autonomous cortisol secretion (MACS); despite only having an unsuppressed cortisol level following LDDS, this patient was found to have a suppressed HPA axis after unilateral adrenalectomy requiring corticosteroids. Early identification and treatment of MACS and treatment of adrenal insufficiency following adrenalectomy is essential to prevent adverse events. Presentation: Thursday, June 15, 2023

Can 3-Phase Computed Tomography Urography Be Used to Characterize Adrenal Nodules? Results in 145 Patients.

The aim of the study is to determine whether computed tomography (CT) urography (CTU) can characterize incidental adrenal nodules. This retrospective cohort study was performed at an academic medical center. Patients were identified by free text search of CTU reports that contained the terms "adrenal mass" "adrenal nodule" and "adrenal lesion." Computed tomography urography technique consisted of unenhanced images and postcontrast images obtained at 100 seconds and 15 minutes. The final cohort included 145 patients with 151 adrenal nodules. Nodules were considered lipid-rich adenomas or myelolipomas based on unenhanced imaging characteristics. Absolute and relative washout values were calculated for the remaining nodules, using a cutoff of 60% and 40%, respectively, to diagnose adenomas. Reference standard for lipid-poor adenomas and malignant nodules was histopathology or imaging/clinical follow-up. Mann-Whitney U test was used for comparison of continuous variables, and Fisher exact test was used for categorical variables. One hundred nodules were lipid-rich adenomas and 3 were myelolipomas. Forty-eight nodules were indeterminate at unenhanced CT, corresponding to 39 lipid-poor adenomas and 9 malignant nodules based on reference standards. Both absolute and relative washout correctly characterized 71% of nodules (34/48), with a sensitivity of 67% and specificity of 89%. Overall, 91% of all adrenal nodules (137/151) were correctly characterized by CTU alone. Lipid-poor adenomas were smaller than malignant nodules (P < 0.01) and were lower in attenuation on unenhanced and delayed images (P < 0.01). Adrenal nodules detected at 3-phase CTU can be accurately characterized, potentially eliminating the need for subsequent adrenal protocol CT or magnetic resonance imaging.

Significance of computed tomography combined with postural stimulation test in predicting laterality of primary aldosteronism

BackgroundsAdrenal venous sampling (AVS) represents the gold standard for classifying primary aldosteronism (PA). However, AVS is a technically demanding, expensive and invasive procedure. Computed tomography (CT) scans is recommended as the initial study of classification diagnosis by the current guidelines. In addition, postural stimulation test (PST) has been used to provide additional subtype diagnostic information.ObjectiveThis work aimed to evaluate the diagnostic utility of the adrenal CT combined with PST in the classification diagnosis of PA.MethodsWe analyzed PA patients who underwent AVS from November 2017 to February 2022 at a single center. Subtype classification of PA was determined by AVS. We analyzed the concordance rate between AVS outcomes, adrenal CT, and PST, and explored the value of adrenal CT combined with PST for predicting laterality of PA.ResultsTotal 531 PA patients were included in the present study. The concordance rate between AVS and the adrenal CT was 51.0%(271/531). Receiver operating characteristic (ROC) curve of PST showed that the area under curve (AUC) was 0.604 [95% confidence interval (CI): 0.556, 0.652], the optimal cut-off value was 30%. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (+LR), and negative likelihood ratio (−LR) of PST for diagnosis bilateral PA on AVS was 72.8, 46.2%, 0.48, 0.71, 1.35, and 0.59, respectively. The prevalence of unilateral PA on AVS in patients with unilateral lesion on CT and negative PST, unilateral lesion on CT and positive PST, bilateral normal or lesions on CT and negative PST, and bilateral normal or lesions on CT and positive PST was 82.4% (108/131), 59.9% (91/152), 50.7% (37/73), and 44.6% (78/175), respectively. The sensitivity, specificity, PPV, NPV, +LR, and -LR of adrenal CT combined with PST for the diagnosis of unilateral PA were 34.4, 89.4%, 0.82, 0.49, 3.25, and 0.73, respectively.ConclusionsThe combination of CT findings and PST can improve the accuracy of predicting laterality of PA.

Automated Adrenal Gland Disease Classes Using Patch-Based Center Symmetric Local Binary Pattern Technique with CT Images.

Incidental adrenal masses are seen in 5% of abdominal computed tomography (CT) examinations. Accurate discrimination of the possible differential diagnoses has important therapeutic and prognostic significance. A new handcrafted machine learning method has been developed for the automated and accurate classification of adrenal gland CT images. A new dataset comprising 759 adrenal gland CT image slices from 96 subjects were analyzed. Experts had labeled the collected images into four classes: normal, pheochromocytoma, lipid-poor adenoma, and metastasis. The images were preprocessed, resized, and the image features were extracted using the center symmetric local binary pattern (CS-LBP) method. CT images were next divided into 16 × 16 fixed-size patches, and further feature extraction using CS-LBP was performed on these patches. Next, extracted features were selected using neighborhood component analysis (NCA) to obtain the most meaningful ones for downstream classification. Finally, the selected features were classified using k-nearest neighbor (kNN), support vector machine (SVM), and neural network (NN) classifiers to obtain the optimum performing model. Our proposed method obtained an accuracy of 99.87%, 99.21%, and 98.81% with kNN, SVM, and NN classifiers, respectively. Hence, the kNN classifier yielded the highest classification results with no pathological image misclassified as normal. Our developed fixed patch CS-LBP-based automatic classification of adrenal gland pathologies on CT images is highly accurate and has low time complexity [Formula: see text]. It has the potential to be used for screening of adrenal gland disease classes with CT images.

The prevalence and spectrum of reported incidental adrenal abnormalities in abdominal computed tomography of cancer patients: The experience of a comprehensive cancer center.

The increasing use of computed tomography (CT) has identified many patients with incidental adrenal lesions. Further evaluation of these lesions is often dependent on the language used in the radiology report. Compared to the general population, patients with cancer have a higher risk for adrenal abnormalities, yet data on the prevalence and type of incidental adrenal lesions reported on radiologic reports in cancer patients is limited. In this study, we aimed to determine the prevalence and nature of adrenal abnormalities as an incidental finding reported on radiology reports of cancer patients evaluated for reasons other than suspected adrenal pathology. Radiology reports of patients who underwent abdominal CT within 30 days of presentation to a tertiary cancer center were reviewed and analyzed. We used natural language processing to perform a multi-class text classification of the adrenal reports. Patients who had CT for suspected adrenal mass including adrenal protocol CT were excluded. Three independent abstractors manually reviewed abnormal and questionable results, and we measured the interobserver agreement. From June 1, 2006, to October 1, 2017, a total of 600,399 abdominal CT scans were performed including 66,478 scans obtained within 30 days of the patient's first presentation. Of these, 58,512 were eligible after applying the exclusion criteria. Adrenal abnormalities were identified in 7,817 (13.4%) reports, with adrenal nodularity (3,401 [43.5%]), adenomas (1,733 [22.2%]), and metastases (1,337 [17.1%]) being the most reported categories. Only 10 cases (0.1%) were reported as primary adrenal carcinomas and 2 as pheochromocytoma. Interobserver agreement using 300 reports yielded a Fleiss kappa of 0.893, implying almost perfect agreement between the abstractors. Incidental adrenal abnormalities are commonly reported in abdominal CT reports of cancer patients. As the terminology used by radiologists to describe these findings greatly determine the subsequent management plans, further studies are needed to correlate some of these findings to the actual confirmed diagnosis based on hormonal, histological and follow-up data and ascertain the impact of such reported findings on patients' outcomes.

ODP611 Combination Of Seated Saline Suppression Test And Computed Tomography In Predicting Subtype Diagnosis Of Primary Aldosteronism In Chinese Population

Abstract Objective The study aimed to evaluate the accuracy of the seated saline suppression test (SSST) combined with adrenal computed tomography (CT) in determining the primary aldosteronism (PA) subtypes. Methods Each patient underwent a SSST and adrenal CT. Logistic diagnostic model (CT finding + post-SSST plasma aldosterone concentration (PAC)) were built, which evaluated the accuracy of the SSST combined with adrenal CT for a subtype classification of PA. Subtype diagnosis of PA was determined by adrenal venous sampling (AVS), pathology and clinical outcomes (primary aldosteronism surgical outcome(PASO)). Results A total of 72 patients with PA were classified into two groups, including 45 aldosterone-producing adenoma (APA) and 27 idiopathic hyperaldosteronism (IHA) patients. By binary logistic regression analysis, adrenal CT (odds ratio (OR)=16.28, 95% confidence interval (CI) 4.18-63.42, P&amp;lt;0. 05) and 4-hours PAC after SSST (OR =1.13, 95% CI 1. 03 to 1.23, P&amp;lt;0. 05) were significantly independent predictors of APA patients. We have successfully developed a diagnostic model based on logistic regression that is able to predict the probability of APA. The area under the receiver operating characteristic (ROC) curve of logistic diagnostic models(AUC=0.907, 95% CI 0.815 to 0.963) was significantly greater either than that for the adrenal CT (AUC=0.807,95% CI 0.696 to 0.890,respectively,P&amp;lt;0. 05) or SSST (AUC=0.799,95% CI 0.688 to 0.884,respectively,P&amp;lt;0. 05). Positive CT finding combined with a post-SSST PAC≥18.2 ng/dL provided sensitivity of 88.89%,specificity of 74. 07%,and positive predictive value (PPV) of 93.9%(31/33) for predicting APA, that determined patients who required AVS prior to surgery. Conclusion The model combining CT finding with post-SSST PAC has superior accuracy in subtype diagnosis of PA compared with SSST or adrenal CT alone. The current study was the first study to investigate the accuracy of the new method on the subtype classification of PA. We are fortunate to find it may be a safe, convenient, sensitive and noninvasive approach in predicting subtype diagnosis of PA in Chinese individuals, especially in primary care where AVS may be unavailable. The results require further confirmation by RCT clinical trials. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

PSAT387 An Unusual Case of Sporadic Metastatic Medullary Thyroid Cancer Without a Primary Tumor Presenting with Paraneoplastic Cushing's Syndrome

Abstract Introduction Medullary thyroid carcinoma (MTC) accounts for 5-10% of all thyroid cancers and up to 30% of MTCs are hereditary. Only 0.6% of MTCs are associated with a paraneoplastic ACTH-dependent Cushing's syndrome (CS) (PMID: 16029131). Even rarer are MTCs without a primary intra-thyroidal tumor. Here we describe a patient with metastatic MTC without a known primary intrathyroidal tumor presenting with paraneoplastic ACTH-dependent CS. Clinical Case A 47-year-old Ukrainian man was referred to our center for management of metastatic MTC. During evaluation of refractory diarrhea two years earlier, an elevated serum calcitonin (1758 pg/mL, normal: &amp;lt;11.5) led to the diagnosis. Thyroid ultrasound revealed a normal thyroid with bulky cervical lymphadenopathy. Cervical lymph node biopsy revealed metastatic MTC with positive calcitonin, synaptophysin, and chromogranin-A on immunohistochemistry (IHC) and RET protooncogene M918T pathogenic variant on molecular testing. Germline testing for RET pathogenic variants was negative. Prior to referral, the patient was on octreotide to control diarrhea and vandetanib for a few months, but they were discontinued due to financial stress. At our center, patient complained of 4-6 watery bowel movements daily. Physical examination revealed facial plethora, dorsocervical fat pad, central adiposity, wide purple striae, and pustular acne on the chest wall and proximal muscle weakness. Biochemical testing revealed elevated serum calcitonin (158,535 pg/mL, normal: &amp;lt;14.3), carcinoembryonic antigen (3,634 ng/mL, normal: 0.8–6.2), and chromogranin-A (5504 ng/mL, normal&amp;lt;93) levels. Morning serum cortisol (40.4 mcg/dL, normal: 3.7–19.4), and plasma ACTH (116.0 pg/mL, normal: 5.0-46.0) levels were elevated, along with markedly elevated 24-hour urine free cortisol levels (12,460.8 mcg/24-hour, normal: 35-45.0), consistent with ACTH-dependent Cushing's syndrome. Further IHC testing of the tumor biopsy sample revealed mild ACTH positivity. A pituitary MRI was normal. Stool osmolality studies showed a secretory diarrhea pattern. Computed tomography (CT) of neck and torso demonstrated bulky cervical, retroperitoneal, and inguinal lymphadenopathy, and extensive liver metastasis, all of which were strongly avid on an 18-fluorodeoxyglucose positron emission tomography CT scan, but poorly avid on a gallium-68 DOTATATE scan. Sodium fluoride bone scan revealed multiple osseous metastases in the spine, ribs, pelvis, and in the right femoral shaft. An adrenal CT scan revealed bilateral adrenal hyperplasia. The patient was unfortunately not eligible for any ongoing local clinical trials on RET-mutated cancer therapies. After extensive discussion with the patient, a palliative approach was pursued. The cervical lymphadenopathy and right femoral shaft metastasis were treated with external beam radiation. Diarrhea was controlled with loperamide. Cushing's syndrome was initially managed with metyrapone and ketoconazole, followed by bilateral adrenalectomy and hydrocortisone and fludrocortisone replacement. Conclusion Sporadic metastatic MTC can rarely present without an intrathyroidal primary tumor and may originate from ectopic C-cells. Paraneoplastic syndromes such as Cushing's syndrome can be observed in MTC due to ectopic-ACTH production. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

Screening for unilateral aldosteronism should be combined with the maximum systolic blood pressure, history of stroke and typical nodules.

To determine factors associated with lateralization in primary aldosteronism (PA). The clinical data for PA patients hospitalized at the First Affiliated Hospital of Guangxi Medical University from October 2016 to March 2021 were included in this study. They were classified according to results derived from computed tomography (CT): bilaterally normal nodules (no typical nodules were found in either adrenal glands, only changes in unilateral adrenal hyperplasia thickening or bilateral adrenal hyperplasia thickening), unilateral nodules (typical nodule appears in unilateral adrenal gland, and there are no abnormalities in the contralateral adrenal gland or only thickening of unilateral adrenal hyperplasia) and bilateral nodules (typical nodule like changes in bilateral adrenal glands). Multivariate logistic regression and receiver operating characteristic (ROC) were used to analyze the factors associated with lateralization of PA and consistencies between adrenal CT images and adrenal venous sampling (AVS) results. A total of 269 patients with PA were recruited, with an average age of 46 years and 112 cases had typical nodules. Results from CT scans revealed that there were 49 bilateral normal cases, 177 cases were unilateral abnormal and 43 cases were bilateral abnormal. In all of the PA patients, multifactorial logistic regression analysis showed that the maximum systolic blood pressure (OR = 1.03, P < .001), history of stroke (OR = 2.61, P = .028), and typical nodules (OR = 1.9, P = .017) were all relevant factors in unilateral primary aldosteronism (UPA). In the unilateral nodule group, multivariate logistic regression analysis suggested that maximum systolic blood pressure (OR = 1.03, P < .001) and typical nodules (OR = 2.37, P = .008) were the related factors for UPA. However, the consistency between adrenal CT and AVS was only 40.68%, while maximum systolic blood pressure (OR = 1.02, P < .001) and plasma aldosterone renin ratio (OR = 1.001, P = .027) were the relevant consistent factors between AVS and CT results. Maximum systolic blood pressure, typical nodules, and history of stroke are important factors to consider when screening for UPA. It is recommended to combine medical history and imaging findings when looking at different subgroups before a clinical decision is made. Patients with PA in the absence of lesions or bilateral lesions on CT should be diagnosed by AVS as far as possible.

Detection of incidental adrenal nodules on computed tomography by radiographers

IntroductionThis research investigated whether radiographers’ age, qualifications, shift rotations and years of post-qualification experience as a radiographer affect the detection rate of incidental adrenal nodules, also known as adrenal incidentalomas in Malta. Additionally, local statistics of adrenal incidentaloma findings were evaluated. MethodsThis research consisted of two phases and employed a non-experimental, cross-sectional quantitative approach. Phase 1 comprised of a self-designed data collection sheet to retrospectively determine the occurrence of recalled computed tomography (CT) examinations resulting from an adrenal incidentaloma finding during a six-month period between July 2020 and December 2020. In phase 2, a self-designed questionnaire with anonymised CT scan images (n = 30) displayed on ViewDex (Viewer for Digital Evaluation of X-ray images) was prospectively completed by CT radiographers (n = 23) to identify adrenal incidentalomas on the images. ResultsIn phase 1, adrenal incidentalomas were present in 1.4% of contrast-enhanced CT (CECT) examinations (n = 12139), out of which, 79.8% were not acknowledged by the radiographers on the initial scans and patients had to be recalled for a dedicated adrenal CT scan. In phase 2, a statistically significant (p < 0.05) relationship was determined between the radiographers’ qualifications, shift rotations and years of post-qualification experience as a radiographer, with their detection rate of adrenal incidentalomas. ConclusionFindings suggest that radiographers’ qualifications, shift rotations and years of post-qualification experience were found to be statistically significant factors affecting their detection rate of adrenal incidentalomas. These could have contributed to one of the reasons for recalling patients, which in turn results in an added burden to both the patient and the Radiology Department. Implications for practiceDetection of adrenal incidentalomas by radiographers has a direct impact on clinical practice. If identified during the initial CT examination and a further delay scan is performed, this will benefit patients by reducing the risks of additional radiation and potential risks from contrast media administration; prompt diagnosis and treatment. While the Radiology Department benefits in terms of cost effectiveness, work load and appointment scheduling.

PRIMARY ALDOSTERONISM: INITIAL EXPERIENCE FROM A NEWLY ESTABLISHED ESH HYPERTENSION CENTER OF EXCELLENCE - WORK IN PROGRESS

Objective: Primary aldosteronism is a common, yet underdiagnosed, cause of hypertension and resistant hypertension. It is estimated to be responsible for 6% of all cases of hypertension and 23% of all cases of resistant hypertension and is associated with disproportionately high rates of cardiovascular events and renal damage relative to the degree of hypertension. We sought to determine the prevalence of primary aldosteronism in patients referred to our center with the diagnosis of hypertension or resistant hypertension Design and method: From 08/03/2021 to 04/01/2022, 46 Patients (18 Females, 39.1%) were evaluated for primary aldosteronism. Thirty two patients (69.6%) were diagnosed with hypertension, of which 22 patients were newly diagnosed and were not on antihypertensive therapy. Fourteen patients (30.4%) were diagnosed with resistant hypertension and were on an average of 4 antihypertensive medications (range, 3 to 7). All were screened with Serum aldosterone (Ald) (pg/ml) and Plasma Renin activity (PRA) (mU/L) levels and ratio. To confirm the diagnosis, a seated saline suppression test (SSST) was performed when the Ald/PRA ratio was above 300. Adrenal computed tomography (CT) and adrenal vein sampling (AVS) were recommended or performed whenever the SSST was positive. Results: Of the 32 Patients with hypertension, 7 had an abnormal Ald/PRA ratio, 2 of which had a SSST which was positive in 1. Of the 14 patients with resistant hypertension, 7 (50%) had an abnormal Ald/PRA ratio, 4 of which underwent a SSST which was positive in all 4. Adrenal CT and AVS were done in 3 patients with resistant hypertension and positive SSST. AVS confirmed unilaterality in 2, both with adrenal adenomas. Adrenalectomy was recommended for the 2 patients and was performed in one with significant improvement in blood pressure control. Conclusions: Although this is a small number of evaluated patients, the data suggests that primary aldosteronism is not rare in hypertensive patients and is a common cause of resistant hypertension. All efforts should be made to improve physicians and patients’ awareness about its prevalence.

Impact of deep learning-based image reconstruction on image quality compared with adaptive statistical iterative reconstruction-Veo in renal and adrenal computed tomography.

OBJECTIVE: To evaluate image quality of deep learning-based image reconstruction (DLIR) in contrast-enhanced renal and adrenal computed tomography (CT) compared with adaptive statistical iterative reconstruction-Veo (ASiR-V).METHODS: We prospectively recruited 52 patients. All images were reconstructed with ASiR-V 30%, ASiR-V 70%, and DLIR at low, medium, and high reconstruction strengths. CT number, noise, noise reduction rate, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured and calculated within the region of interest (ROI) on subcutaneous fat, bilateral renal cortices, renal medulla, renal arteries, and adrenal glands. For qualitative analyses, the differentiation of the renal cortex and medulla, conspicuity of the adrenal gland boundary, sharpness, artifacts, and subjective noise were assessed. The overall image quality was calculated on a scale from 0 (worst) to 15 (best) based on the five values above and the score≥9 was acceptable.RESULTS: CT number does not significantly differ between the reconstruction datasets. Noise does not significantly differ between ASiR-V 30% and DLIR-L, but it is significantly lower using ASiR-V 70%, DLIR-M, and DLIR-H. The noise reduction rate relative to ASiR-V 30% is significantly different between the DLIR groups and ASiR-V 70%, and DLIR-H yields the highest noise reduction rate (61.6%). SNR and CNR are higher for DLIR-M, DLIR-H, and ASiR-V 70% than for ASiR-V 30% and DLIR-L. DLIR-H shows the best SNR and CNR. The overall image quality yields the same pattern for DLIR-H, with the highest score. Percentages of cases with overall image quality score≥9 are 100% (DLIR-H), 94.23% (DLIR-M), 90.38% (ASiR-V70%), 67.31% (DLIR-L), and 63.46% (ASiR-V30%), respectively.CONCLUSIONS: DLIR significantly improved the objective and subjective image quality of renal and adrenal CTs, yielding superior noise reduction compared with ASiR-V.

Are the washout values currently accepted for lesion characterization in dedicated adrenal CT adequate for diagnosis?

We aimed to investigate the accuracy of density characteristics and washout values of lesions detected on computed tomography (CT) at the cutoff values obtained from the literature by taking the pathological results of adrenalectomy specimens as reference and to determine the cutoff values of parameters evaluated on CT for the differentiation of adenoma and nonadenoma lesions in the study group. Hospital records and standard CT imaging data (noncontrast early phase [65 s] and late phase [15 min] ) of 84 patients with 87 lesions who underwent adrenalectomy between January 2012 and December 2018 were retrospectively reevaluated by two radiologists in consensus. The patients were categorized as having adenoma and nonadenoma lesions according to the pathology results. The sensitivity, specificity and diagnostic accuracy of CT parameters (density values and washout percentages) were evaluated. Differences in the CT parameters (size, noncontrast and early-late enhancement density and absolute and relative washout values) were investigated. The optimal cutoff values of CT parameters were determined by ROC analysis. Noncontrast CT had a specificity of 87.75% and 95.9%, sensitivity of 60% and 48.6%, diagnostic accuracy of 77.7% and 89.47% for adenomas, at the cutoff values of ≤10 HU and ≤0 HU, respectively. For absolute washout value ≥ 60%, the sensitivity, specificity and accuracy were 64.7%, 52.38% and 56.75%, respectively; while these rates were 76.47%, 56.52% and 62.16%, respectively, for relative washout value ≥40%. Adenomas and nonadenomas showed significant difference in terms of size (p < 0.0001), unenhanced attenuation (p < 0.0001), relative washout (p = 0.020) and delay enhancement (p < 0.001). But there were no differences in terms of absolute washout (p = 0.230) and early enhancement (p = 0.264). The cutoff values for the differentiation of adenomas and nonadenomas were as follows: size ≤44 mm, noncontrast density <20 HU, early-phase density ≥45 HU, delayed-phase density ≤44 HU, absolute washout 74.83% and relative washout 57.76%. The current washout criteria used in the differentiation of adenoma and nonadenoma lesions in dynamic CT imaging can give false negative and positive results. According to the existing criteria, the most reliable parameter in adenoma-nonadenoma differentiation is ≤ 0 HU noncontrast CT density value.

Hyperattenuating adrenal lesions in lung cancer: biphasic CT with unenhanced and 1-min enhanced images reliably predicts benign lesions.

To investigate usefulness of biphasic computed tomography (CT) in characterizing hyperattenuating adrenal lesions in lung cancer. This retrospective study included 239 patients with lung cancer who underwent adrenal CT for hyperattenuating (> 10 Hounsfield unit) adrenal lesions. Adrenal CT comprised unenhanced and 1-min and 15-min enhanced images. We dichotomized adrenal lesions depending on benign or metastatic lesions. Reference standard for benignity was histologic confirmation or ≥ 6-month stability on follow-up CT. Two independent readers analyzed absolute (APW) or relative percentage wash-out (RPW) using triphasic CT, and enhancement ratio (ER) or percentage wash-in (PWI) using biphasic CT (i.e., unenhanced and 1-min enhanced CT). Criteria for benignity were as follows: criteria 1, (a) APW ≥ 60% or (b) RPW ≥ 40%, and criteria 2, (a) ER > 3 and (b) PWI > 200%. We analyzed area under the curve (AUC) and accuracy for benignity, and inter-reader agreement. Proportion of benign adrenal lesion was 71.1% (170/239). For criteria 1 and 2, AUCs were 0.872 (95% confidence interval [CI], 0.822-0.911) and 0.886 (95% CI, 0.838-0.923), respectively, for reader 1 (p = 0.566) and 0.816 (95% CI, 0.761-0.863) and 0.814 (95% CI, 0.759-0.862), respectively, for reader 2 (p = 0.955), and accuracies were 87.9% (210/239) and 86.2% (206/239), respectively, for reader 1 (p = 0.479) and 81.2% (194/239) and 80.3% (192/239), respectively, for reader 2 (p = 0.763). Weighted kappa was 0.725 (95% CI, 0.634-0.816) for criteria 1 and 0.736 (95% CI, 0.649-0.824) for criteria 2. Biphasic CT can reliably characterize hyperattenuating adrenal lesions in patients with lung cancer. • Criteria from biphasic computed tomography (CT) for diagnosing benign adrenal lesions were enhancement ratio of > 3 and percentage wash-in of > 200%. • In the analysis by two independent readers, area under the curve between criteria 1 and 2 was not significantly different (0.872 and 0.886 for reader 1; 0.816 and 0.814, for reader 2; p > 0.05 for each comparison). • Wash-in characteristics from biphasic CT are helpful to predict benign adrenal lesions in lung cancer.

Distinguishing pheochromocytoma from adrenal adenoma by using modified computed tomography criteria.

To investigate the performance of modified criteria to distinguish pheochromocytoma from adrenal adenoma by using adrenal protocol computed tomography (CT). We retrospectively included consecutive 199 patients who underwent adrenal CT and surgically proven pheochromocytoma (n = 66) or adenoma (n = 133). Two independent radiologists analyzed two CT criteria for pheochromocytoma. Conventional criteria were as follows: (a) lesion attenuation on unenhanced CT > 10 Hounsfield unit (HU); (b) absolute percentage washout < 60%; and (c) relative percentage washout < 40%. Modified criteria were as follows: (a) conventional criteria or (b) one of the following findings: (i) lesion attenuation on unenhanced CT ≥ 40 HU, (ii) 1-min enhanced CT ≥ 160 HU, (iii) 15-min enhanced CT ≥ 70 HU, , or (iv) intralesional cystic degeneration seen on both 1-min and 15-min enhanced CT. We analyzed area under the curve (AUC) and inter-reader agreement. Proportion of pheochromocytoma was 33.2% (66/199). AUC of modified criteria was consistently higher than that of conventional criteria for distinguishing pheochromocytoma from adenoma (reader 1, 0.864 versus 0.746 for raw data set and 0.865 versus 0.746 for internal validation set; reader 2, 0.872 versus 0.758 for raw data set and 0.872 versus 0.757 for internal validation set) (p < 0.05 for all comparisons). Inter-reader agreement was excellent in interpreting any criteria (weighted kappa > 0.800). Our modified criteria seem to improve diagnostic performance of adrenal CT in distinguishing pheochromocytoma from adrenal adenoma.

Diagnostic performance of adrenal CT in the differentiation of adenoma and pheochromocytoma.

Differentiation of adenoma and pheochromocytoma on computed tomography (CT) may be problematic. To investigate if adenoma and pheochromocytoma can be differentiated with adrenal CT. A total of 147 pathologically proven adrenal masses (119 adenomas, 28 pheochromocytomas) that had undergone adrenal CT were retrospectively evaluated. Lesion attenuation on unenhanced phase (UEP), portal phase (PP), 15-min delayed phase (DP), absolute/relative percentage enhancement wash-out (APEW/RPEW), and qualitative features were recorded. Student's t-test for parametric data, Mann-Whitney U test for non-parametric data, and Fisher's exact test for categorical data were used. Diagnostic performance of CT attenuation was assessed by area under the curve (AUC) of the receiver operating characteristics. APEW of adenomas was not significantly different from pheochromocytomas; 68.4% and 59% (P = 0.284). Adenomas had significantly higher RPEW; 57.3% vs. 37.4% (P = 0.004). Of pheochromocytomas, 50% met APEW >60% or RPEW >40% criteria, and therefore were misclassified as adenoma on wash-out CT. Of those, 80% (4/5) were < 3 cm. UEP, PP, and DP attenuations of pheochromocytomas were significantly higher than adenomas; however, they were overlapping. AUC for UEP, PP, and DP was 0.906, 0.784, and 0.926, respectively. Larger pheochromocytomas were more likely to contain necrosis compared to smaller pheochromocytomas and adenomas; 41.6% vs. 12.5% vs. 3%. Homogeneous enhancement was seen in 25% of pheochromocytomas and 49% of adenomas (P = 0.018). No significant difference was found in terms of lesion borders and presence of fat/calcification (P > 0.05). A considerable percentage of pheochromocytomas, especially smaller ones, demonstrate adenoma-like wash-out on CT. Heterogeneous enhancement, higher attenuation, and necrosis are more suggestive of pheochromocytoma.

The effect of patient positioning on adrenal gland linear measurements estimated from computed tomographic images in healthy beagle dogs

Considering that recumbency can lead to a change in localization, detectability of distinct margins and thus measurement of the organs and reconstruction quality, it is of value to evaluate the effect of positioning on the objective evaluation of abdominal organs in computed tomography (CT). The objective of the present study was to evaluate the effect of patient decubitus on adrenal gland CT biometry. For this purpose, 6 clinically healthy adult beagle dogs underwent CT examination in 4 recumbencies. The various adrenal gland's size measurements were performed by 2 observers. Statistical analyses revealed that repeatability and reproducibility was the highest on the ventral and right lateral recumbencies, respectively. Significant differences were found in the left adrenal gland's length between the different positions (P < 0.001) and the left adrenal gland's width of the cranial pole measured in the dorsal plane (P < 0.04). The measurements on the parasagittal images differed significantly for the left adrenal length (P = 0.01), cranial pole height (P = 0.03), the right adrenal gland's lateral limb's length (P = 0.05) and medial limb's caudal poles height (P < 0.01). The caudal pole height of the right adrenal gland's medial limb was significantly different (P < 0.01) in all positions on the transverse images. In addition, the adrenal position differed significantly, except for the left adrenal gland relative to the nearest renal vessel (P = 0.1). According to these results, it is recommended to perform a CT of adrenal glands always in the same recumbency. If adrenal glands are evaluated on images taken in various recumbencies, we suggest relying on the measurements made on transverse plane images.

SAT-070 Clinical and Imaging Characteristics of Primary Unilateral Adrenal Hyperplasia in Primary Aldosteronism

Primary aldosteronism (PA) is the most common cause of endocrine hypertension (HT) with an estimated prevalence of 10% in referred populations and 15–20% in patients with resistant HT. Aldosterone-producing adenomas are the most common cause of unilateral PA. Primary unilateral adrenal hyperplasia (PUH) is a rare cause of PA, but is probably underestimated. PUH can be diffuse or nodular, with poorly capsulated micronodules. To date, there is a paucity of data characterizing this condition. In this study, our aim was to report the clinical and imaging features of patients with PA caused by PUH. We retrospectively evaluated clinical, imaging and histopathological data of 183 PA patients. PUH was diagnosed in 9 out of 183 patients (5%). All patients had biochemical cure of PA after unilateral adrenalectomy and anatomopathological analysis showed micronodular adrenal hyperplasia in all cases. At the diagnosis, median age was 52 yrs, ranging from 33 and 74 yrs (6 men and 3 women). Hypokalemia was reported in 63% of the cases. Aldosterone/plasmatic renin activity ratio was 123.6 (range, 52 to 379). The median duration of HT was 18 yrs (range, 1 to 52). Because of HT duration before diagnosis, only a patient had HT cure after adrenalectomy. The median follow-up was 46 months (7 to 117 months). Computed tomography (CT) accuracy to determine the lateralization was 67%. The adrenal CT findings were: normal adrenals (n= 1), bilateral hyperplasia (n= 1; right incidentaloma 1.9 cm and left PUH 1.4 cm), unilateral hyperplasia (n= 1), bilateral nodules (n= 1) and unilateral nodules (n= 5; median 1.3 cm, from 0.9 to 1.5). Adrenal venous sampling was performed in 5 patients (successful rate 80%). In the remaining cases, surgery was guided by CT. PUH was in the left adrenal in 7 out of 9 cases (78%). Hot spot somatic mutations in aldosterone-driver genes (KCNJ5, ATP1A1, ATP2B3 and CTNNB1) were excluded by Sanger automated sequencing and the presence of chimeric CYP11B1/CYP11B2 gene was ruled out by long-PCR in all cases. In conclusion, PUH prevalence in our cohort was higher than previously reported. PUH was more frequent in men and in the left adrenal. The most common CT finding was a unilateral nodule smaller than 1.5 cm. However, CT accuracy was low and AVS should be the gold standard to define lateralization. Support: CNPq (403256/2016-0) to MQA; FAPESP (2017/13394-8) to MRC.