NP-59 SPECT/CT imaging in stage 1 hypertensive and atypical primary aldosteronism: a 5-year retrospective analysis of clinicolaboratory and imaging features.

OBJECTIVE: We retrospectively analyzed all primary aldosteronism (PA) patients undergoing NP-59 SPECT/CT imaging with regard to their clinicolaboratory and imaging features, investigation, and outcomes. MATERIAL AND METHODS: 11 PA patients who presented to our hospital for NP-59 SPECT/CT imaging between April 2007 and March 2012 and managed here were analyzed. RESULTS: Among 11 PA patients, eight (73%) had stage 1 hypertension, three (27%) stage 2 hypertension, four (36%) normal plasma aldosterone concentration, nine (82%) nonsuppressed plasma renin activity (PRA), six (55%) normal aldosterone-renin-ratio (ARR), eight (73%) serum potassium ≧3 mEq/L, seven (64%) subclinical presentation, seven (64%) negative confirmatory testing, and four (36%) inconclusive results on CT scan and seven (64%) on planar NP-59 scan. All 11 (100%) patients had positive results on NP-59 SPECT/CT scan. Two (18%) met typical triad and nine (82%) atypical triad. Among nine atypical PA patients, three (33%) had clinical presentation, six (67%) subclinical presentation, six (67%) negative confirmatory testing, and four (44%) inconclusive results on CT scan and six (67%) on planar NP-59 scan. All patients had improved outcomes. Significant differences between typical and atypical PA existed in PRA and ARR. CONCLUSIONS: NP-59 SPECT/CT may provide diagnostic potential in stage 1 hypertensive and atypical PA.

Asymptomatic metastasis to the larynx detected by FDG PET/CT in a patient with recurrent rectal adenocarcinoma.

Metastasis of colorectal adenocarcinoma to the larynx is a very rare condition. Here, we report a 72-year-old woman with a history of rectal adenocarcinoma. She was referred for whole-body FDG PET/CT scanning because of an elevating serum level of carcinoembryonic antigen. PET images showed focally increased FDG accumulation in the larynx (SUVmax=12.9). Coregistered CT images showed mild wall thickening at the left subglottic area. The findings of after excisional biopsy confirmed that this FDG-avid lesion was metastatic adenocarcinoma of the colorectal origin.

FDG uptake in sacroiliac joint due to osteitis condensans ilii shown on PET/CT in a patient with breast cancer: the value of coregistered CT in avoiding misinterpretation.

A 56-year-old woman with breast cancer underwent FDG PET/CT at follow-up. The PET images showed increased FDG uptake along right sacroiliac joint. The coregistered CT images showed diffuse sclerosis around the sacroiliac joints, but no bony destruction, periarticular erosion, or joint space narrowing. She had been complaining of intermittent lower back pain since her last pregnancy. The radiologic pictures and history of postpartum back pain were considered as typical characteristics for osteitis condensans ilii. This case reminds us that careful inspection of the coregistered CT images is important to avoid potential misinterpretation because of osteitis condensans ilii.

Diagnosis of primary aldosteronism in chronic kidney disease by I-131 NP-59 SPECT/CT imaging.

Primary aldosteronism (PA) may be missed in patients with chronic kidney disease (CKD), because CKD may disturb the renin-angiotensin-aldosterone system. Adrenal vein sampling has increased risks in patients with CKD. We report the case of a 58-year-old man with CKD and suspected PA. Left adrenal aldosteronism was diagnosed by NP-59 SPECT/CT. Left adrenalectomy demonstrated adrenocortical nodular hyperplasia. Plasma aldosterone normalized and blood pressure stabilized after surgery. NP-59 SPECT/CT may be a helpful diagnostic tool for detecting and lateralizing PA in CKD patients.

Diagnostic value of I-131 NP-59 SPECT/CT scintigraphy in patients with subclinical or atypical features of primary aldosteronism.

Accumulating evidence has shown the adverse effect of long-term hyperaldosteronism on cardiovascular morbidity that is independent of blood pressure. However, the diagnosis of primary aldosteronism (PA) remains a challenge for patients who present with subtle or atypical features or have chronic kidney disease (CKD). SPECT/CT has proven valuable in the diagnosis of a number of conditions. The aim of this study was to determine the usefulness of I-131 NP-59 SPECT/CT in patients with atypical presentations of PA and in those with CKD. The records of 15 patients with PA were retrospectively analyzed. NP-59 SPECT/CT was able to identify adrenal lesion(s) in CKD patients with suspected PA. Patients using NP-59 SPECT/CT imaging, compared with those not performing this procedure, significantly featured nearly normal serum potassium levels, normal aldosterone-renin ratio, and smaller adrenal size on CT and pathological examination and tended to feature stage 1 hypertension and non-suppressed plasma renin activity. These findings show that noninvasive NP-59 SPECT/CT is a useful tool for diagnosis in patients with subclinical or atypical features of PA and those with CKD.

Use of laxative-augmented contrast medium in the evaluation of colorectal foci at FDG PET.

PURPOSE: To compare the diagnostic accuracy of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in the detection of colon lesions with that of delayed PET/computed tomography (CT) performed after the administration of a laxative-augmented contrast medium. MATERIALS AND METHODS: All patients gave written informed consent according to the guidelines issued by the institutional review board. In a prospective study performed from November 2005 to December 2006, images obtained in 847 patients were reviewed by two physicians in consensus. Colorectal FDG uptake on initial PET images that exceeded background FDG accumulation was graded as minimal, equivocal, or positive. When the initial PET scan revealed a colorectal region of increased uptake, either oral or anal laxative-augmented contrast medium was administered on the basis of the site of colorectal FDG focus and delayed PET/CT was performed. Initial PET findings were reevaluated and revised when necessary. Comparison was performed on a per-patient basis. Findings at histopathologic analysis and clinical follow-up served as the reference standard. The accuracy of PET was compared with that of PET/CT by using the McNemar test. RESULTS: Colorectal FDG foci were seen on initial images in 137 patients. Uptake on the initial images was reported as minimal in 14 patients, equivocal in 68, and positive in 55. With use of a laxative-augmented contrast medium and delayed PET/CT, the proportions of equivocal and positive results decreased by 84% (57 of 68 patients) and 58% (18 of 31 patients), respectively. The accuracy of delayed PET/CT in the depiction of colorectal cancer was greater than that of initial PET (93.4% [128 of 137 patients] vs 71.5% [98 of 137 patients], respectively; P < .01). CONCLUSION: Delayed PET/CT with laxative-augmented contrast medium is more accurate than initial PET alone in the detection of colorectal cancer. This approach has promise as a tool for guiding decisions about how to treat patients with colorectal FDG foci. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101193/-/DC1.

Kidney impairment in primary aldosteronism.

BACKGROUND: Kidney impairment is noted in primary aldosteronism (PA), and probably initiated by glomerular hyperfiltration. METHODS: A prospectively defined survey was conducted on 602 patients who were suspected of PA in the multiple-center Taiwan Primary Aldosteronism Investigation (TAIPAI) database. Estimated glomerular filtration rate (eGFR) was calculated and followed up at 1 yr after treatment. RESULTS: The diagnosis of PA was confirmed in 330 patients. Among them 17% of these patients had kidney impairment (eGFR<60 ml/min/1.73 m²). Patients with PA had a higher prevalence of estimated hyperfiltration than those with essential hypertension (EH) (14.5% vs. 7.0%, p=0.005). The eGFR independently predicted PA (OR, 1.017) in the propensity-adjusted multivariate logistic model. In PA, plasma renin activity and lower serum potassium (p=0.018) was correlated with kidney impairment (p=0.001), while this relationship was not significant in patients with EH. Either unilateral adrenalectomy or treatment of spironolactone for PA patients caused a decrease of eGFR (p<0.001). Pre-operative hypokalemia (p=0.013) and the long latency of hypertension (p=0.016) could enhance the significant decrease of eGFR after adrenalectomy. CONCLUSIONS: Patients with aldosteronism had relative estimated hyperfiltration than patients with EH. Calculation of eGFR may increase the specificity in identifying patients with PA. Our findings demonstrate the correlation of serum potassium and renin with estimated hyperfiltration in PA and their relationship to kidney damage. These results provide a high priority for future renal protective strategies and methods for the early diagnosis and prompt treatment of PA.

Application of an artificial neural network to predict postinduction hypotension during general anesthesia.

BACKGROUND: Perioperative hypotension is associated with adverse outcomes in patients undergoing surgery. A computer-based model that integrates related factors and predicts the risk of hypotension would be helpful in clinical anesthesia. The purpose of this study was to develop artificial neural network (ANN) models to identify patients at high risk for postinduction hypotension during general anesthesia. METHODS: Anesthesia records for March through November 2007 were reviewed, and 1017 records were analyzed. Eleven patient-related, 2 surgical, and 5 anesthetic variables were used to develop the ANN and logistic regression (LR) models. The quality of the models was evaluated by an external validation data set. Three clinicians were asked to make predictions of the same validation data set on a case-by-case basis. RESULTS: The ANN model had an accuracy of 82.3%, sensitivity of 76.4%, and specificity of 85.6%. The accuracy of the LR model was 76.5%, the sensitivity was 74.5%, and specificity was 77.7%. The area under the receiver operating characteristic curve for the ANN and LR models was 0.893 and 0.840. The clinicians had the lowest predictive accuracy and sensitivity compared with the ANN and LR models. CONCLUSIONS: The ANN model developed in this study had good discrimination and calibration and would provide decision support to clinicians and increase vigilance for patients at high risk of postinduction hypotension during general anesthesia.

Colovesical fistula in a patient with recurrent cervical cancer detected by FDG PET/CT.

We report the case of a 57-year-old woman with the history of stage IB cervical cancer. She was found to have a metastatic squamous cell carcinoma in sigmoid colon. FDG PET/CT was then performed for whole-body cancer work-up. Intense FDG activity accumulated in the sigmoid tumor, with an unusually high SUVmax of 72.42, and was seen downwardly connected with the activity of urinary bladder on PET images. On the coregistered CT images, irregular wall thickening was noted for both sigmoid colon and urinary bladder with a hypodensity tract communicating with each other. It was concluded that recurrent cervical cancer involving urinary bladder and sigmoid colon resulted in colovesical fistula.

Artificial neural network to predict skeletal metastasis in patients with prostate cancer.

The application of an artificial neural network (ANN) in prediction of outcomes using clinical data is being increasingly used. The aim of this study was to assess whether an ANN model is a useful tool for predicting skeletal metastasis in patients with prostate cancer. Consecutive patients with prostate cancer who underwent the technetium-99m methylene diphosphate (Tc-99m MDP) whole body bone scintigraphies were retrospectively analyzed between 2001 and 2005. The predictors were the patient's age and radioimmunometric serum PSA concentration. The outcome variable was dichotomous, either skeletal metastasis or non-skeletal metastasis, based on the results of Tc-99m MDP whole body bone scintigraphy. To assess the performance for classification model in clinical study, the discrimination and calibration of an ANN model was calculated. The enrolled subjects consisted of 111 consecutive male patients aged 72.41 +/- 7.69 years with prostate cancer. Sixty-seven patients (60.4%) had skeletal metastasis based on the scintigraphic diagnosis. The final best architecture of neural network model was four-layered perceptrons. The area under the receiver-operating characteristics curve (0.88 +/- 0.07) revealed excellent discriminatory power (p < 0.001) with the best simultaneous sensitivity (87.5%) and specificity (83.3%). The Hosmer-Lemeshow statistic was 6.74 (p = 0.08 > 0.05), which represented a good-fit calibration. These results suggest that an ANN, which is based on limited clinical parameters, appears to be a promising method in forecasting of the skeletal metastasis in patients with prostate cancer.

Predicting hypotensive episodes during spinal anesthesia with the application of artificial neural networks.

Hypotension is one of the most frequent adverse effects of spinal anesthesia. Several factors might be related to the occurrence of hypotension. Predictions of the hypotensive event, however, had been addressed by only a few authors using logistic regression (LR) models. Artificial neural networks (ANN) are pattern-recognition tools that can be used to detect complex patterns within data sets. The purpose of this study was to develop the ANN-based predictive model to identify patients with high risk of hypotension during spinal anesthesia. From September 2004 to December 2006, the anesthesia records of 1501 patients receiving surgery under spinal anesthesia were used to develop the ANN and LR models. By random selection 75% of data were used for training and the remaining 25% of data were used as test set for validating the predictive performance. Five senior anesthesiologists were asked to review the data of test set and to make predictions of hypotensive event during spinal anesthesia by clinical experience. The ANN model had a sensitivity of 75.9% and specificity of 76.0%. The LR model had a sensitivity of 68.1% and specificity of 73.5%. The area under receiver operating characteristic curves were 0.796 and 0.748. The ANN model performed significantly better than the LR model. The prediction of clinicians had the lowest sensitivity of 28.7%, 22.2%, 21.3%, 16.1%, and 36.1%, and specificity of 76.8%, 84.3%, 83.1%, 87.0%, and 64.0%. The computer-based predictive model should be useful in increasing vigilance in those patients most at risk for hypotension during spinal anesthesia, in allowing for patient-specific therapeutic intervention, or even in suggesting the use of alternative methods of anesthesia.

Atypical angioma serpiginosum.

Angioma serpiginosum is an uncommon, acquired vascular nevoid disorder with capillary dilation and proliferation in the papillary dermis. The eruptions are asymptomatic and characterized by grouped, erythematous to violaceous, serpiginous and punctate macules. The condition usually appears in females during adolescence on unilateral lower extremities and the buttocks. We report a rare case with a late onset and atypical distribution of lesions in a 48-year-old female patient who had groups of punctate lesions on her left foot for four to five years. Histopathological examination showed hyperkeratosis and multiple dilated and proliferated capillaries in the papillary dermis. Inflammation and extravasation of red blood cells were not found. According to the clinical and pathological findings, we established a diagnosis of angioma serpiginosum. She was treated with a pulsed dye laser, and the angiomatous lesions subsequently improved.