Biomedical subjects

Pietro Zucchetta

Publications and source records attributed to Pietro Zucchetta.

7 recordsLinked to original sources

PubMed2006

Sensitivity and positive predictive value of CT, MRI and 123I-MIBG scintigraphy in localizing pheochromocytomas: a prospective study.

AIM: To establish a standardized non-invasive imaging protocol for patients with pheochromocytoma undergoing surgery. METHODS: A series of 32 consecutive patients (16 men, 16 women; median age 43 years, range 15-71 years) with biochemically confirmed pheochromocytoma underwent computed tomography (CT) scanning, magnetic resonance imaging (MRI) and meta-[I]iodobenzylguanidine (MIBG) whole-body scintigraphy prior to adrenalectomy or excision of extra-adrenal tumour (paraganglioma). RESULTS: At final pathology no malignant pheochromocytomas were found. The tumour was right-sided in 16 (50%) patients, left-sided in 13 (41%), extra-adrenal (sympathetic ganglia, upper abdomen) in two (6%) and bilateral in one (3%) patient. Overall, the median greatest diameter (size) of the tumour was 35 mm (range, 15-90 mm). The sensitivity of CT, MRI and MIBG scintigraphy was 90%, 93% and 91%, and the specificity was 93%, 93% and 100%, respectively. The three patients with false negative scintigraphy had an intra-adrenal tumour, ranging from 20 to 50 mm in size. The presence of necrosis within the mass might justify the lack of significant uptake of radiopharmaceutical in two patients, and the small size (15 mm) of the mass in the other. There were two false positive results with both CT and MRI, and no false positive MIBG scintigraphy, which had the highest (100%) positive predictive value. The combination of MRI+MIBG scintigraphy reached 100% sensitivity and positive predictive value. CONCLUSION: Our data suggest that this imaging protocol should be used in all patients with biochemically confirmed pheochromocytoma.

3-Iodobenzylguanidine↗

PubMed2005

Confirmatory tests in the diagnosis of brain death: comparison between SPECT and contrast angiography.

OBJECTIVE: Cerebral blood flow tests have increasingly been advocated for the confirmation of brain death (BD). Four-vessel angiography has been considered the most reliable investigation in the diagnosis of BD for >30 yrs, but it is invasive. (99m)Tc-HMPAO SPECT provides noninvasive, multiplanar imaging of brain tissue perfusion. The aim of this study was to check the reliability of SPECT compared with contrast angiography. DESIGN: Prospective, blind study. SETTING: Neurointensive care unit of a university hospital. PATIENTS: Consecutive clinically brain dead patients with flat electroencephalogram. INTERVENTIONS: BD was diagnosed according to Italian law. (99m)Tc-HMPAO SPECT and four-vessel angiography were performed in the same session; the rater of each investigation ignored the results of the other. Blood pressure, Sp(O2), and P(ECO2) were monitored throughout the study: any episode of hypoxia or hypotension caused exclusion of the patient from the study. MEASUREMENTS AND MAIN RESULTS: Twenty brain dead patients were enrolled. The cause of BD was head injury in seven cases (35%), subarachnoid hemorrhage in seven (30%), spontaneous hemorrhage in one (10%), brain tumors in two (10%), stroke in two (10%), and thrombosis of the sagittal sinus in one (5%). Both angiography and SPECT confirmed BD in 19 of 20 patients: angiography showed the absence of filling of intracranial arteries, while SPECT showed a picture of "empty skull." For the remaining patient, angiography showed slight and late filling of left vertebral, basilar, and posterior cerebral arteries, while SPECT showed faint traces of uptake in the posterior fossa on the right side and on the midline. For this patient, the tests were repeated 48 hrs later, and both showed the arrest of intracranial circulation, thus confirming BD. CONCLUSIONS: Our results confirm the reliability of SPECT in the diagnosis of BD; because SPECT is noninvasive, it is a good candidate for the "gold standard" of diagnosis.

Adult↗

PubMed2004

Cardiopulmonary anatomy and function in long-term survivors of mild to moderate congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: In the last decades, several studies regarding cardiopulmonary sequelae in survivors of congenital diaphragmatic hernia (CDH) have been published, but results often are conflicting, and controversies still exist. The aim of this study was to assess cardiopulmonary anatomic and functional outcome in a group of long-term survivors of CDH of mild to moderate degree. METHODS: Twenty-four children aged 8.15 +/- 2.80 years underwent clinical examination with growth assessment, chest radiographs, echocardiography, pulmonary perfusion scintigraphy, static lung volumes measurement, and spirometry. RESULTS: Mean Z scores of weight for age and height for age were within normal values. Echocardiography showed normal anatomy and function in all but 3 patients with isolated CDH, in whom minor alterations were detected. Mean perfusion to the affected side was significantly lower (45.16 +/- 5.30%; P <.0001) but still within normal range. Four children showed a substantial impairment of perfusion to the hernia side. The mean spirometric values and pulmonary volumes were normal. However, a mild restrictive pattern was evident in 6 children (27.3%), an obstructive pattern in 3 (13.6%), and a mixed obstructive and restrictive impairment in 1. CONCLUSIONS: Hypoplastic lungs of mild to moderate CDH survivors continue to cause pulmonary morbidity in some children many years after the correction of the defect. In particular, lung perfusion appears to be impaired in 20% of the patients and pulmonary function in 45%, without any significant cardiac or developmental sequelae. The negative correlation between FEV1 and duration of ventilation at presentation (r = -0.49; P =.026) may be caused by the consequences of lung hypoplasia, but initial ventilatory management may contribute to increased pulmonary morbidity. Relationship between perfusion and FEF25-75 (r = 0.61; p = 0.004) could reflect an equivalent degree of reduction in the caliber of distal airways and pulmonary vascular tree.

Abnormalities, Multiple↗

PubMed2004

Selective decrease in urinary aquaporin 2 and increase in prostaglandin E2 excretion is associated with postobstructive polyuria in human congenital hydronephrosis.

This study was undertaken to determine the role of aquaporin 2 (AQP2) in the impaired urinary concentrating capacity observed in patients who underwent pyeloplasty because of congenital unilateral hydronephrosis as a result of pyeloureteral junction disease. Twelve children (mean age, 8 +/- 2 mo) were examined in the study. From day 1 to day 5 after surgery, the urine was collected separately from pyelostomy draining only from the postobstructed kidney and from the bladder catheter draining mostly from the contralateral kidney used as internal control. After pyeloplasty, the postobstructed kidney was characterized by a reduced urinary excretion of AQP2 (approximately 54%) associated with polyuria that persisted from day 1 to day 5 (433 +/- 58 versus 310 +/- 74 ml/24 h at day 1; 326 +/- 44 versus 227 +/- 26 ml/24 h at day 5). In parallel, urine osmolality from the postobstructed kidney was significantly reduced compared with the contralateral kidney (111 +/- 12 versus 206 +/- 49 at day 1; 136 +/- 24 versus 235 +/- 65 mOsm/kg at day 5). Creatinine clearance from the postobstructed kidney was not significantly different compared with the contralateral kidney throughout the 4 d after surgery. However, on day 5, creatinine clearance from the postobstructed kidney became significantly lower. Prostaglandin E2 in the urine from postobstructed kidneys was found to be twofold higher than in the contralateral samples (26.0 +/- 6.7 versus 13.5 +/- 2.5 at day 5). It is concluded that (1) the selective downregulation of AQP2 in postobstructed kidney may account for the higher excretion of hypotonic urine, and (2) the local increase in prostaglandin E2 synthesis in postobstructed kidney may be involved in AQP2 downregulation and in maintaining a GFR similar to that of the contralateral kidney.

Adolescent↗

PubMed2004

Suprarenal fixation of endograft in abdominal aortic aneurysm treatment: focus on renal function.

OBJECTIVE: The objective of this work was to evaluate any variation of renal function detected by renal scintigraphy after the suprarenal fixation of endografts for abdominal aortic aneurysm (AAA) repair. SUMMARY BACKGROUND DATA: In the few articles that have considered this problem, renal function was evaluated only by biochemical tests, which are inadequate in demonstrating small changes in renal function and in appreciating the worsening of a single kidney's function. METHODS: Between April 1999 and May 2002, 47 patients with an inappropriate infrarenal proximal neck had a suprarenal fixation for AAA. To assess renal function, a technetium-99m diethylene triamine penta-acetic acid (TC-DTPA) perfusion scintigraphy was performed preoperatively on the third postoperative day and at 6, 12 months, and then yearly thereafter. Worsening of renal function was defined as a decrease of glomerular filtration rate (GFR) > or =20% (detected with Gates method). Serum creatinine level was tested preoperatively and at the first and third postoperative day. RESULTS: Endograft deployment was technically successful in 44 patients (93.6%); clinical perioperative success was obtained in 46 patients (97.8%). In 12 patients (25.5%), a permanent reduction of the GFR was observed using postoperative TC-DTPA perfusion scintigraphy. By 99m TC-DTPA perfusion scintigraphy, a permanent reduction of GFR was observed postoperatively in 12 patients. A slight GFR reduction (<20%) was present in 7 (14.9%) patients, due to the planned occlusion of accessory renal arteries. A more significant GFR reduction (>20%) was present unexpectedly in 5 (10.6%) patients, in 3 of these a single kidney was involved, in 5 both with an increase of the serum creatinine level >20%. CONCLUSIONS: Suprarenal fixation of endografts in AAA treatment is a safe procedure with good early and midterm procedural results and a risk of GFR impairment (>20%) of 10.6%.

Aged↗

PubMedDate not supplied

Usefulness of 99mTc-pertechnetate scintigraphy and fine-needle aspiration cytology in patients with solitary thyroid nodules and thyroid cancer.

The aim of this study was to evaluate the accuracy of fine-needle aspiration (FNA) cytology and thyroid scintigraphy (TS) in patients with solitary thyroid nodules. We retrospectively reviewed a series of 657 consecutive patients (531 (80.8%) women and 126 (19.2%) men, median age 45 years, range 16-81 years) with solitary thyroid nodules. Prior to surgery, all patients underwent FNA cytology whilst 99mTc-pertechnetate TS was performed in 496 (75.5%) patients. Final histopathology showed 533 (81.1%) benign nodules, including 251 (38.2%) follicular adenomas and 124 (18.9%) thyroid carcinomas. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy in the detection of thyroid cancer were 95.8%, 21.1%, 22.6%, 95.5% and 35.7% for TS, and 81.4%, 99.4%, 97.1%, 95.8% and 96.0% for FNA cytology. The presence of thyroid cancer was confirmed in 92 out of 407 (22.6%) patients with a "cold" nodule, in 4 (4.5%) patients who had normal or increased uptake on TS, in 101 out of 104 (97.1%) patients with smears suggesting malignancy, and in 3 out of 533 (0.6%) smears suggesting benign lesions. In conclusion, the specificity of TS is low and this technique should be abandoned as a routine test in patients with nontoxic thyroid nodules. However, a more careful evaluation should be suggested for patients with cold thyroid nodules and a FNA cytology that reads follicular neoplasm.

Adolescent↗

PubMedDate not supplied

Role and cost-effectiveness of adrenal imaging and image-guided FNA cytology in the management of incidentally discovered adrenal tumours.

Incidentally discovered adrenal masses (incidentalomas) are relatively frequent and unsuspected incidentalomas (AI) of more than 1 cm in size may be found in 1-5% of patients who have undergone abdominal or chest computed tomography (CT)-scan for unrelated reasons. Once an AI is detected, the two major questions are whether the patient has biochemical evidence of adrenal hyperfunction, and whether the mass is an adrenal metastasis or a malignant adrenal tumour. In most cases (>90%) AI are non-functioning, with a low (<10%) risk of being malignant, and an estimated cumulative risk of malignant transformation of less than 1:1000. However, all patients with non-functioning AI usually undergo several imaging studies, but the impact of imaging techniques and image-guided fine-needle aspiration cytology (FNAC) on the cost-effectiveness in the management of patients is not well established. A single test for disease probabilities is not always more cost-effective than two-test approaches and it has been shown that the cumulative sensitivity and accuracy of both FNAC + magnetic resonance imaging (MRI) and FNAC + norcholesterol adrenal scintigraphy reach 100%, at a similar cost-to-accuracy ratio (7.5 vs. 7.0), whilst the strategy CT-scan + MRI together is less sensitive at a lower cost-to-accuracy ratio. In conclusion, the significance of AI, as well as the optimal management approach to treatment, is still under discussion. However, image-guided FNAC in conjunction with MRI as the exclusive imaging test has the major role and cost-effectiveness in the management of patients with AL, and should be considered the strategy of choice in distinguishing between benign and malignant non-functioning adrenal masses of more than 2 cm in diameter.

Adrenal Gland Neoplasms↗