T2-weighted, apparent diffusion coefficient and 18F-FDG PET histogram analysis of rectal cancer after preoperative chemoradiotherapy.

BACKGROUND: The aim of our study was to investigate the correlation among T2-weighted (T2w) images, apparent diffusion coefficient (ADC) maps, 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) images, histogram analysis and the pathological response in locally advanced rectal cancer (LARC) after preoperative chemoradiotherapy (pCRT). METHODS: Patients with LARC were prospectively enrolled between February 2015 and August 2018 and underwent PET/magnetic resonance imaging (MRI). MRI included T2w and diffusion-weighted imaging (DWI)-sequences. ADC maps and PET images were matched to the T2w images. Voxel-based standardized uptake values (SUVs,) ADC and T2w-signal-intensity values were collected from the volumes of interest (VOIs) and mean, skewness and kurtosis were calculated. Spearman's correlation coefficient was applied to evaluate the correlation among the variables and tumor regression grade (TRG), T stage, N stage and fibrosis. RESULTS: Twenty-two patients with biopsy-proven LARC in the low or mid rectum were enrolled [17 males, mean age was 69 years (range 49-85 years)]. Seven patients experienced complete regression (TRG1). A significant positive correlation was found between SUV mean values (ρ = 0.480; p = 0.037) and TRG. No other significant correlations were found. CONCLUSIONS: Histogram analysis of SUV values is a predictor of TRG in LARC.

Lung visualisation on PET/MRI: implementing a protocol with a short echo-time and low flip-angle volumetric interpolated breath-hold examination sequence.

AIM: To assess the diagnostic performance in detecting lung lesions of a short echo-time (TE) and low flip-angle (FA) volumetric interpolated breath-hold examination (VIBE) sequence included in the integrated positron-emission tomography (PET)/magnetic resonance imaging (MRI) protocol. METHOD AND MATERIALS: Thirty-seven oncological patients who underwent computed tomography (CT) and PET/MRI, including both a dedicated short TE, low FA VIBE (modified VIBE) and a standard VIBE of the lung, were enrolled. Modified VIBE images were reviewed retrospectively and independently by three raters, to detect pulmonary nodules, parenchymal consolidation, and bands. Three other groups examined standard VIBE, PET, and CT images. MRI and PET findings were compared to CT using Krippendorff's alpha using patient-based and a lesion-based analysis. Krippendorff's alpha was calculated to assess the interobserver agreement among the three raters of the modified VIBE. RESULTS: In the patient-based analysis (positivity ≥1 lesion), the comparison of modified VIBE with CT showed an alpha of 0.54 for nodules <6 mm (versus 0.41 for standard VIBE and 0.09 for PET) and an alpha of 0.88 for nodules ≥6 mm (versus 0.74 for standard VIBE and 0.42 for PET). On a lesion-based analysis (presence/absence of each lesion), modified VIBE compared to CT showed an alpha of0.58 for nodules <6 mm (versus 0.44 for standard VIBE and 0.09 for PET) and an alpha of 0.90 for nodules ≥6 mm (versus 0.79 for standard VIBE and 0.50 for PET). The alpha value for the interobserver agreement was 0.90 for nodules <6 mm, 0.91 for nodules ≥6 mm, 1.00 for consolidations, and 0.95 for bands in the patient-based analysis and 0.89, 0.93, 1.00, and 0.95 in the lesion-based analysis. CONCLUSIONS: Modified VIBE proved to be reproducible, showed better accuracy than standard VIBE and PET, and very good concordance with CT in assessing lung nodules ≥6 mm, whereas the agreement was less satisfactory for smaller nodules.

Bickerstaff's brainstem encephalitis: case report and Tc99m brain SPECT findings.

A 21-year-old healthy female suffered from an upper respiratory tract infection and 2 days later developed diplopia, unsteady gait, dysarthria and a profound disturbance of consciousness with rapid development of coma. Brain MRI and Tc99m brain perfusion SPECT, EEG, neurophysiological tests and CSF analysis results were unspecific. The detection of serum anti-GQ1b IgG autoantibodies at high titre led to the diagnosis of Bickerstaff's brainstem encephalitis (BBE). Clinical symptoms resolved after treatment with plasma exchange and the outcome was good. Brain MRI was normal, and Tc99m brain perfusion SPECT demonstrated hypoperfusion of the whole cerebral hemispheres and basal ganglia with relative sparing of the thalami and the brainstem. Similar to brain MRI, the sensitivity of Tc99m brain perfusion SPECT in detecting brainstem lesions in typical BBE patients seems to be low.

Retrospective study on PET-SPECT imaging in a large cohort of myotonic dystrophy type 1 patients.

The aim was to study brain involvement in myotonic dystrophy type 1 by single photon emission tomography (SPECT) and positron emission tomography (PET). 58 DM1 patients were subjected to SPECT; 17 to both SPECT and PET. SPECT patients were grouped as 'normally perfused' and 'abnormally perfused'; PET patients as 'normal performers' and 'abnormal performers'. To quantify hypoperfusion and/or hypometabolism, we used a semi-quantitative scale. To localize focal hypoperfusion/hypometabolism, nine cerebral areas of involvement were identified. The Chi-square, Wilcoxon, McNemar tests were used for statistics. SPECT showed abnormalities in 52/58 patients. PET showed an abnormal glucidic uptake in 15/17. Hypoperfusion was mild/moderate in 50/58 patients, mostly involving the left supratentorial areas. Abnormal glucidic uptake was mainly observed in the left frontal lobe. Abnormalities in blood perfusion and/or glucose metabolism are frequent in DM1. These abnormalities involve the left more often than the right hemisphere, the frontal lobe more than other lobes. Such abnormalities are more often cortical than subcortical.

Pyeloplasty vs. nephrectomy for ureteropelvic junction obstruction in poorly functioning kidneys (differential renal function <20%): a multicentric study.

INTRODUCTION: Management of poorly functioning kidneys with ureteropelvic junction obstruction (UPJO) is controversial, with some recommending direct nephrectomy and others direct pyeloplasty, and others temporary diversion. This study aimed to determine whether pyeloplasty is associated with higher complication rate than nephrectomy under these circumstances and whether it allows for functional recovery. METHODS: A retrospective review of 77 patients undergoing surgery for UPJO associated with a differential renal function (DRF) < 20% at 4 centres between January 2000 and December 2015 was conducted. Short- and long-term complications between pyeloplasties (n = 47) and nephrectomies (n = 16) and the changes in the DRF after pyeloplasty were compared. RESULTS: Patients undergoing nephrectomy had significantly lower median pre-operative DRF (p < 0.001) and were significantly more likely to undergo a minimally invasive approach (p = 0.002) than those undergoing pyeloplasty. No postoperative variable was statistically different between groups. After a mean follow-up of 63 (10-248) months, no statistically significant difference was found in intra-operative, early, late, and overall complications between pyeloplasty and nephrectomy. Pyeloplasty failed in 3% (2/62) of cases. Of the patients undergoing successful pyeloplasty, 36 had a pre-operative and a postoperative renogram, and functional recovery >5% was observed in 13 (36%), whereas the DRF remained unchanged in 16 (45%). Only postnatal diagnosis was associated with a significantly higher chance of functional recovery (odds ratio [OR] = 4.13, p = 0.047). DISCUSSION: Nephrectomy was more commonly performed using a minimally invasive approach and required less-intense follow-up than pyeloplasty. Moreover, complications after pyeloplasty, although occasional, required additional surgery which was never required after nephrectomy. Moreover, it should be considered that conservative treatment might be a third option in some of these patients. CONCLUSIONS: In the study patients, pyeloplasty was not associated with significantly higher morbidity than nephrectomy. Need for deferred nephrectomy seems exceptional in decompressed kidneys even though renal function remains poor. Of the pyeloplasty cases not requiring additional surgery, one-third showed an improvement in DRF and a postnatal diagnosis was the only predictive factor for renal functional recovery.

Voiding cystourethrography and 99MTC-MAG3 renal scintigraphy in pediatric vesicoureteral reflux: what is the role of indirect cystography?

BACKGROUND: Primary vesicoureteral reflux (VUR) is the most common urological anomaly in children. Voiding cystourethrography (VCUG) is considered the reference standard for the diagnosis of VUR. Even if it is a secure and standardized technique, it is still an invasive method, hence, the effort to find an alternative method to diagnose VUR. The aim of the study is to evaluate the diagnostic accuracy of 99mTC-MAG3 scintigraphy with indirect cystography in detecting VUR and to estimate any interobserver variability in 99mTC-MAG3 scintigraphy interpretation. METHODS: The authors retrospectively reviewed all the pediatric patients who underwent both a VCUG and a 99mTC-MAG3 renal scintigraphy at the study institution between 2012 and 2016. RESULTS: A total of 86 children (and 168 renal units) were included. MAG3 scan revealed a sensitivity of 54% and a specificity of 90% with positive predictive value of 79% and negative predictive value of 73%. Each MAG3 scintigraphy was then independently and blindly evaluated by a pediatric urologist and two nuclear physicians. After revision, the concordance between VCUG and MAG3 in reflux cases dropped from 54% to 27% (on average), and the reviewers reclassified most examinations as non-conclusive. CONCLUSIONS: 99mTC-MAG3 renal scintigraphy with indirect cystography showed low sensitivity in detecting VUR of any grade and cannot, therefore, be proposed as completely alternative to VCUG in the diagnosis of VUR. Moreover, MAG3 scintigraphy interpretation for the diagnosis of VUR has a very high interobserver variability, mostly because of the lack of a correct and complete voiding phase.

Microvascular autonomic dysfunction may justify false-positive stress myocardial perfusion imaging in patients with liver cirrhosis undergoing liver transplantation.

BACKGROUND: Up to 15% of liver transplant candidates have asymptomatic coronary artery diseases, which increase the risk of cardiac complications during and after transplantation. The aim of this study was to prospectively investigate the usefulness of an integrated cardiological approach in cirrhotic patients undergoing liver transplantation. METHODS: Twenty-four consecutive patients undergoing evaluation for liver transplantation were studied by assessing risk factors for coronary artery diseases, electrocardiogram with QTc interval determination, chest X-ray, echocardiography, 24-hour Holter monitor, myocardial perfusion scintigraphy (99mTc)MIBI-GSPECT at rest and after dipyridamole infusion. Cardiac (123)I-metaiodobenzylguanidine (MIBG) scan and coronarography were performed in patients with myocardial perfusion defects. Twenty three of 24 patients underwent successful liver transplantation; one patient died on the waiting list. RESULTS: Before liver transplantation, 29% of patients were diabetic and 41% were smokers. Eleven of 24 patients had a prolonged QTc interval, and 3/24 had positive myocardioscintigraphy after dipyridamole infusion: in two coronarography was negative, while the (123)I-MIBG washout was altered. No cardiac events were recorded during the short-and long-term follow-up after surgery. CONCLUSIONS: Predictive value of positive cardiac (99mTc)MIBI-GSPECT in patients with liver cirrhosis is low, and this may be due to alterations of cardiac microvascular tone as showed by cardiac (123)I-MIBG scan.

[Sjögren's syndrome: comparison among the main imaging techniques in the study of major salivary glands]. / Sindrome di Sjögren: confronto fra le principali tecniche di imaging per lo studio delle ghiandole salivari maggiori.

Sjögren's syndrome (SS) is a chronic inflammatory disease with an autoimmune etiology, that affects exocrine glands, in particular salivary and lacrimal glands. Among the diagnostic criteria of SS, imaging techniques play an important role. The aim of our study is to compare three imaging techniques, such as sonography, scintigraphy and sialography in the evaluation of major salivary glands. The use of the these techniques is of great importance for the diagnosis of SS. Sonography is the most frequently used for its prompt execution, non invasivity, great acceptance by the patient and low cost. In the diagnostic patient management of SS, sonography results are eventually confirmed by the other imaging techniques, sialography and scintigraphy.

A meta-iodobenzylguanidine scintigraphic scoring system increases accuracy in the diagnostic management of pheochromocytoma.

As observed by other authors, normal adrenal medullary tissue frequently gives an apparently positive meta-iodobenzylguanidine (MIBG) scan in cases studied using 123I-MIBG and less frequently 131I-MIBG. The aim of this study was to assess the usefulness of a scoring system, based on different uptakes of the radiopharmaceutical, to improve the accuracy of 123I-MIBG scintigraphy in patients with either adrenal or extra-adrenal pheochromocytomas. Charts from 67 consecutive patients (29 males and 38 females, median age 48 years, range 14-80 years) with suspected pheochromocytoma (either sporadic or familial: multiple endocrine neoplasia (MEN) 2a, MEN2b, Von Hippel-Lindau, neurofibromatosis type 1) who underwent 123I-MIBG scintigraphy (scans acquired 4-24 h after injection) from 1991 to 2004, were independently reviewed by two experienced nuclear medicine physicians using liver uptake as a reference (scores: 1, uptake absent or less than the liver; 2, equal to the liver; 3, moderately more intense than the liver; 4, markedly more intense than the liver). Interfering medications were discontinued for the appropriate time before MIBG injection. Histological data were obtained for all patients who underwent adrenalectomy. Scintigraphies were classified as positive using the following criteria: extra-adrenal focal uptake, adrenal enlargement together with non-homogeneous uptake and adrenal uptake more intense than the liver (score 3-4). After surgical resection, as confirmed by histological findings and long-term follow-up (range 1-14 years, average 9.25 years), 43 patients were considered true positives using the proposed scoring system, 20 were true negatives, four were false negatives and none was false positive. In conclusion, the proposed scoring system demonstrated high specificity (100%), sensitivity (91.5%) and accuracy (94%) in the management of pheochromocytoma. Positive predictive value and negative predictive value were 100% and 83.3% respectively. Normal adrenal tissue uptake was correctly discriminated from pheochromocytomas in 18 out of 20 patients, with adrenal uptake equal to the liver (grade 2), using the proposed cut-off level.

Relationship between prognostic factors of breast cancer and 99mTc-sestamibi uptake in patients who underwent scintimammography: Multivariate analysis of causes of false-negative results.

The complementary role of sestamibi scintimammography (SSM) in patients with breast cancer (BC) is well established. The aim of this study was to establish whether a relationship exists between sestamibi uptake, evaluated as a tumour-to-background ratio (TBR), and the main prognostic factors of BC. SSM with the measurement of TBR was performed preoperatively in 102 women (median age 57 years, range 32-81 years) who underwent curative surgery for primary BC. Final pathology showed 4 (3.9%) with pT1a, 17 (16.7%) with pT1b, 44 (43.1%) with pT1c and 37 (36.3%) with pT2 breast carcinomas. The overall sensitivity of SSM was 80.4%. An ANOVA showed significant (P<0.01) differences between the TBR of patients with G1 vs. G3 tumours, and between the TBR of those with G2 vs. G3 breast carcinomas. Moreover, there was a difference (P=0.021) between the TBR of patients (n=12, 11.8%) with CEA serum levels >10 ng/ml (2.031+/-0.420), and those with normal (n=90, 88.2%) CEA values (1.713+/-0.446), whilst no difference (P=NS) was found between patients (n=27, 26.5%) with CA 15-3 >30 U/ml (1.893+/-0.401) and those with normal (n=75, 73.5%) CA 15-3 values (1.699+/-0.462). There was a mild inverse correlation between TBR and both the oestrogen (R=0.25, P=0.011) and the progesterone receptor (R=0.23, P=0.02) rate. The logistic regression analysis showed that only size and CA 15-3 serum levels represent true independent parameters, but the function was able to predict only 11 out of 21 (52.4%) patients with false-negative SSM. TBR is independent of age and mainly correlates with the size of the tumour. There are no reliable preoperative prognostic factors that are really useful for improving SSM sensitivity in patients with small breast carcinomas.

Accuracy of ultrasonography and 99mTc-sestamibi scintimammography for assessing axillary lymph node status in breast cancer patients. A prospective study.

AIMS: The aim of this study was to evaluate the sensitivity, specificity and accuracy of axillary ultrasonography (US) and (99m)Tc-sestamibi scintimammography (SSM) in patients with breast cancer (BC) undergoing curative surgery. METHODS: A series of 77 consecutive women (median age 54 years, range 36-70) with primary BC underwent both US and SSM from 2 to 15 (median 4) days prior to curative surgery. The results of imaging studies were compared against the final pathology. Breast-conserving surgery with axillary node (AN) dissection was performed in 49 (63.6%) patients, and modified radical mastectomy in 28 (36.4%) patients, according to the tumour staging. RESULTS: Final pathology showed 5 pT1bN0, 1 pT1bN1, 28 pT1cN0, 19 pT1cN1, 7 pT2N0, and 17 pT2N1 BC. Overall, 719 AN were removed of which 106 (14.7%) were metastatized nodes (median 3, range 1-5 per patient). The sensitivity, specificity and accuracy were 67.6%, 80.0%, and 74.0% for US, 78.4%, 85.0%, and 81.8% for SSM, and 91.9%, 92.5%, and 92.2% for US and SSM together, respectively. There was a significant difference (p<0.05) in the number of metastatized AN between patients with metastases correctly detected and undetected by both US (3.1+/-1.3 vs. 2.0+/-0.7) and SSM (3.2+/-1.3 vs. 1.7+/-0.7). CONCLUSIONS: Although the results of each diagnostic tests are strictly dependent on the number of the metastatized AN, the combination of axillary US and SSM is a sensitive low-cost procedure that should be suggested in all patients with BC, when a preoperative evaluation of the AN status is required.

Calculating regional tissue volume for hyperthermic isolated limb perfusion: Four methods compared.

INTRODUCTION: Hyperthermic isolated limb perfusion (HILP) can be performed as an alternative to amputation for soft tissue sarcomas and melanomas of the extremities. Melphalan and tumor necrosis factor-alpha are used at a dosage that depends on the volume of the limb. Regional tissue volume is traditionally measured for the purposes of HILP using water displacement volumetry (WDV). Although this technique is considered the gold standard, it is time-consuming and complicated to implement, especially in obese and elderly patients. AIM: The aim of the present study was to compare the different methods described in the literature for calculating regional tissue volume in the HILP setting, and to validate an open source software. METHODS: We reviewed the charts of 22 patients (11 males and 11 females) who had non-disseminated melanoma with in-transit metastases or sarcoma of the lower limb. We calculated the volume of the limb using four different methods: WDV, tape measurements and segmentation of computed tomography images using Osirix and Oncentra Masterplan softwares. RESULTS AND CONCLUSION: The overall comparison provided a concordance correlation coefficient (CCC) of 0.92 for the calculations of whole limb volume. In particular, when Osirix was compared with Oncentra (validated for volume measures and used in radiotherapy), the concordance was near-perfect for the calculation of the whole limb volume (CCC = 0.99). With methods based on CT the user can choose a reliable plane for segmentation purposes. CT-based methods also provides the opportunity to separate the whole limb volume into defined tissue volumes (cortical bone, fat and water).

Hyperfunctioning parathyroid tumours in patients with thyroid nodules. Sensitivity and positive predictive value of high-resolution ultrasonography and 99mTc-sestamibi scintigraphy.

A series of 112 consecutive patients with primary hyperparathyroidism who underwent both high-resolution neck ultrasonography (US) and 99mTc-sestamibi/99mTc-pertechnetate subtraction scintigraphy (SS) prior to successful parathyroidectomy was reviewed. There were 29 (25.9%) men and 83 (74.1%) women, with a median age of 58 years (range 13-78 years). Patients were divided into two groups, according to the preoperative US findings: group A (87 patients, 77.7%) without thyroid diseases, and group B (25 patients, 22.3%) with either multinodular goitre or a solitary nontoxic thyroid nodule. In group B patients partial or total thyroidectomy was also performed, according to the intraoperative findings and frozen-section examination results. Final histopathology showed 99 (88.4%) solitary parathyroid (PT) adenomas and 3 (2.7%) PT carcinomas, while 10 (8.9%) patients had a multiglandular disease. The sensitivity and positive predictive value (PPV) were (group A vs group B) 79.8% vs 70.8% (P=0.25) and 95.7% vs 94.4% (P=0.58) for US, and 83.3% vs 87.0% (P=0.47) and 95.9% vs 90.9% (P=0.32) for SS respectively. Better but similar (P=not significant) results were obtained in patients with solitary PT tumours: 81.5% vs 77.8% (US) and 85.0 vs 94.1% (SS) sensitivity; 97.1% vs 93.3% (US) and 95.8% vs 88.9% (SS) PPV. Overall, the combination of US and SS was 92.9% sensitive (group A=93.1%, group B=92.0%; P=0.55), and the PPV reached 100% in each group. In conclusion, in patients with primary hyperparathyroidism the results of both US and SS are independent of coexistent thyroid disease, especially in patients with solitary PT tumours.

Noninvasive localization procedures in ectopic hyperfunctioning parathyroid tumors.

In primary hyperparathyroidism (pHPT), parathyroidectomy is the treatment of choice, but anatomic variations of ectopic glands may cause surgical failure. Reliable preoperative noninvasive localization procedures would have a positive impact on the operative time and increase recovery rate. We retrospectively evaluated 186 patients with pHPT who were studied before successful parathyroidectomy by double tracer scintigraphy (99mTc-pertechnetate+201TI chloride or 99mTc-pertechnetate +99mTc-sestamibi, 160 patients), ultrasonography (148 patients) and computerized tomography (CT) scan (92 patients). During bilateral neck exploration, 159 (85.5%) single adenomas, 6 (3.2%) parathyroid carcinomas, and 3 (1.6%) double adenomas were found. Moreover, 18 (9.7%) patients had diffuse chief cells parathyroid hyperplasia. Removed parathyroid glands were in ectopic sites in 41 (22.0%) cases, mainly localized in the upper mediastinum or behind the esophagus. The overall sensitivity was 83.5 and 85.2% for 99mTc-pertechnetate+201TI chloride and 99mTc-pertechnetate+99mTc-sestamibi scintigraphy respectively, 80.4% for CT scan and 81.1% for ultrasonography. In patients with ectopic glands, sensitivity was 81.2, 79.5, 73.3 and 81.6% respectively. In 36 out of 41 patients with ectopic glands in whom the removed parathyroids were correctly localized, mean operative time was 95 min, and in 5 patients without preoperative localization it was 260 min. In conclusion, in pHPT, preoperative localization of an enlarged parathyroid is helpful, especially in ectopic adenomas and in anatomic variations in location, and it has been proved to reduce operative time and morbidity rate.

Localization of parathyroid tumours in the minimally invasive era: which technique should be chosen? Population-based analysis of 253 patients undergoing parathyroidectomy and factors affecting parathyroid gland detection.

A series of 253 consecutive patients with proved primary hyperparathyroidism due to parathyroid tumours was reviewed. There were 68 (26.9%) men and 185 (73.1%) women, with a median age of 57 years (range 13-82 years). All patients, prior to successful parathyroidectomy, underwent one or more preoperative localization procedures such as: neck ultrasonography (US) in 191 (75.5%), (201)Tl/(99m)Tc-pertechnetate subtraction scintigraphy (TPS) in 144 (56.9%), CT scan in 92 (36.4%), (99m)Tc-sestamibi/(99m)Tc-pertechnetate subtraction scintigraphy (MPS) in 90 (35.6%), selective venous sampling (SVS) with parathyroid hormone (PTH) assay in 30 (11.9%), and magnetic resonance imaging (MRI) in 6 (2.4%) patients. The results were compared with operative and histological findings that showed 235 (92.9%) solitary parathyroid adenomas, 13 (5.1%) carcinomas and 5 (2.0%) double adenomas. Sensitivity and positive predictive value were 82.9% and 93.8% for US, 83.6% and 91.8% for TPS, 81.3% and 98.7% for CT scan, 85.1% and 96.1% for MPS, 65.4% and 80.9% for SVS, and 80.0% and 80.0% for MRI respectively. No different results (P=NS) were found using US, TPS, MPS or CT scan, whereas SVS and MRI sensitivity was lower (P<0.05). The combination of MPS and US was 94.0% sensitive (P<0.05) but when TPS, CT scan or MRI were also used overall sensitivity did not improve significantly (P=NS). In conclusion, MPS should be used as the starting preoperative localization procedure, while US and MPS together represent the most reliable noninvasive localization tool. If MPS and US are negative or not in agreement, further studies are not cost-effective and the patient should undergo bilateral neck exploration.

Comparison between echocardiographic subtraction method and first-pass radionuclide ventriculography for measuring right ventricular volume after operative "repair" of patients with tetralogy of Fallot.

In the long-term follow-up of patients after repair of tetralogy of Fallot, monitoring right ventricular function is mandatory. The echocardiographic subtraction method proposed by Tomita seems to be easily applicable to a pediatric age population and accurate enough to be included in the longitudinal surveillance of such a group of patients.

Scintigraphic patterns of adrenocortical carcinoma: morpho-functional correlates.

OBJECTIVE: Adrenocortical scintigraphy has demonstrated clinical utility in the morpho-functional characterization of adrenal tumors. The aim of this study was to identify possible relationships between the scintigraphic pattern and endocrine and/or morphological data in a series of adrenocortical carcinomas. DESIGN AND METHODS: Twenty-one patients with adrenocortical carcinoma (11 nonfunctioning and 10 hormone-secreting) were investigated with 75Se-methyl-nor-cholesterol scintigraphy. Clinical, hormonal, radiological, and pathological data were analyzed. RESULTS: The adrenal mass showed no radiocholesterol uptake in 18 cases (11 nonfunctioning and 7 functioning lesions). Contralateral normal adrenal gland was visualized in all patients with nonfunctioning tumors, whereas classic bilateral nonvisualization was observed in the 7 cases with hyperfunctioning masses. Three patients with cortisol-producing carcinomas showed radiotracer uptake by the mass, without visualization of the contralateral gland. At histology, the tumors were shown to be undifferentiated adrenocortical carcinomas; they had an aggressive clinical behavior. CONCLUSIONS: Radiocholesterol scintigraphy has an important role in diagnosing adrenocortical carcinomas, which typically are not visualized. However, 30% of hypersecreting adrenocortical carcinomas show an atypical increased tracer uptake, not predictive of the biochemical and histological features of the tumor.

Advantages of combined technetium-99m-sestamibi scintigraphy and high-resolution ultrasonography in parathyroid localization: comparative study in 91 patients with primary hyperparathyroidism.

OBJECTIVE: To evaluate the usefulness of the combination of Tc-sestamibi/Tc-pertechnetate subtraction scintigraphy (SS) and high-resolution neck ultrasonography (US) in patients with primary hyperparathyroidism (pHPT) undergoing parathyroidectomy. DESIGN AND METHODS: Ninety-one patients with proved pHPT were studied, excluding patients with persistent or recurrent disease. There were 65 (71.4%) women and 26 (28.6%) men, with a median age of 59 years (range 18-78 years). All patients underwent both SS and US prior to surgery, and the results were compared with operative and histological findings. The intraoperative quick-parathyroid hormone assay was available for 52 (57.1%) patients. When multiglandular disease was found, both SS and US were considered truly positive only when at least two enlarged parathyroid (PT) glands had been localized. RESULTS: Eighty-three (91.2%) solitary PT adenomas and three (3.3%) carcinomas were found. Moreover, two (2.2%) patients had a double adenoma and three (3.3%) patients had diffuse PT hyperplasia. The overall sensitivity of combined SS+US was 94.5% (86.8% and 80.4% for SS and US respectively). There was a significant (P<0.05, Student's t-test) difference in size between the PT glands correctly identified and undetected by SS, whereas the site of the removed PT tumors significantly (P<0.05, Fisher exact test) influenced only the US sensitivity. CONCLUSIONS: When the preoperative localization of the PT glands is chosen, the combination of SS and US represents a reliable noninvasive localization technique and should be considered for use in each patient with pHPT undergoing surgery.

99mTc-HMPAO SPECT in the diagnosis of brain death.

OBJECTIVE: To evaluate the effectiveness of single proton emission tomography (SPECT) with 99mTc-HMPAO in the diagnosis of brain death (BD). DESIGN: Prospective study in comatose and brain-dead patients. SETTING: Neurologic ICU. PATIENTS AND METHODS: Fifty comatose patients (age range: 10 days-75 years) were submitted to SPECT study. In 21 of them (42%) reversible factors (e.g., influence of drugs affecting the central nervous system) were present. Thirty-eight patients were clinically brain-dead, while the remaining 12 were tested both in pre-terminal conditions and after the clinical onset of BD. INTERVENTIONS: Brain SPECT following i.v. injection of 99mTc-HMPAO (300-1100 MBq), using a 4-headed gamma-camera (20 min, 360 degrees, 88 images). MEASUREMENTS AND RESULTS: All patients tested in pre-terminal conditions showed preserved brain perfusion. Two of them had flat EEGs despite the absence of any reversible cause of coma; three patients survived, but remained in persistent vegetative states. SPECT confirmed the diagnosis of BD in 45 out of 47 patients (95.7%), clearly showing the arrest of brain perfusion (picture of "empty skull"); in two clinically brain-dead children (aged 10 days and 12 months, respectively) weak perfusion of the basal ganglia, thalamus and/or brain stem was still present, precluding the diagnosis of BD; both of them died a few days later. CONCLUSIONS: Our results confirm the reliability of SPECT in the diagnosis of BD. A problem arises about its effectiveness in brain-dead children, but this seems to be a matter of definition of BD and cerebral viability, rather than a limit of SPECT.