Lucio Maria Porfiri

High-resolution scintimammography improves the accuracy of technetium-99m methoxyisobutylisonitrile scintimammography: use of a new dedicated gamma camera

Abstract. The main disadvantage of technetium-99m methoxyisobutylisonitrile (MIBI) prone scintimammography is its limited sensitivity for T1a and T1b cancers with a size of less than 1 cm. We have developed a high-resolution scintimammographic technique using a gamma camera based on a new concept, namely a position-sensitive photo-multiplier tube. The field of view of this camera, previously known as the SPEM (single photon emission mammography) camera, was 10 cm diameter. Scintimammographic images were acquired in the axial view; each breast was compressed to a thickness of 3–6 cm, modal class 4 cm. When the compressed breast was larger than the field of view, more than one study was performed in order to image the entire gland. Fifty-three patients were studied with high-resolution-scintimammography (HRSM) and Anger camera prone scintimammography (ACPSM). HRSM was performed 70 min after i.v. administration of 740 Mbq of 99mTc-MIBI; ACPSM images were acquired 10 and 60 min following the injection. Early 10-min ACPSM images were only evaluated for routine diagnostic purposes, while comparison was carried out between the 60-min ACPSM and 70-min HRSM images. At fine-needle aspiration (FNA) and/or open biopsy, 31 patients showed cancer: 15 T1c, 11 T1b and 5 T1a. In T1a-T1b cancers, the sensitivity of scintimammography was 50% with ACPSM and 81.2% with HRSM (P<0.01). Specificity was 86% with both techniques. HRSM is a promising new technique that improves the sensitivity of 99mTc-MIBI scintimammography in tumours sized less than 1 cm without apparently reducing its specificity. We are now working on a larger field-of-view camera.

Evaluation of normal brain development by prenatal MR imaging.

AbstractPurpose.The aim of this study was to describe the normal pattern of development and maturation of the foetal brain with respect to gestational age as assessed with magnetic resonance imaging (MRI) and to provide an overview of the possibilities of the technique.Materials and methods.Foetal cerebral MRI was performed on 56 pregnant women between 19 and 37 weeks of gestation. Half-Fourier single-shot turbo spin-echo (HASTE), true fast imaging with steady precession (FISP), T1-weighted fast low angle shot (FLASH) two-dimensional (2D) and diffusion-weighted (DW) sequences with apparent diffusion coefficient (ADC) were obtained. Biometric parameters and developmental areas of the cerebral cortex were correlated to gestational age by using the Spearman rank correlation test.Results.We found a negative correlation between the germinal matrix/biparietal diameter ratio and gestational age and a positive correlation between the germinal and cortical matrix when expressed as external intraocular diameter ratio (R=0.452, p=0.02). The cortical mantle was correlated with biometric parameters, such as the biparietal diameter and the frontooccipital diameter, and with gestational age. The interhemispheric fissure, the parietooccipital fissure and the sylvian fissure were detectable by the 22nd week. In the grey matter, the mean ADC values varied from 1.76×10-3 mm2/s (at week 19) to 0.89×10-3 mm2/s (at week 37), whereas in the white matter, the values varied from 2.03×10-3 mm2/s (at week 19) to 1.25×10-3 mm2/s (at week 37).Conclusions.MRI provides a reliable valuation of brain maturation during pregnancy.

Role of breast Magnetic Resonance Imaging (MRI) in patients with unilateral nipple discharge: preliminary study

PurposeThis study was performed to assess the role of magnetic resonance imaging (MRI) in patients with unilateral nipple discharge.Materials and methodsForty-four patients with bloody or serosanguineous nipple discharge and negative mammographic findings (35/44 cases) underwent MRI for evaluation of breast ducts. Ultrasonography, negative in 18 patients, identified 26 cases of ductal ectasia (12 simple, nine with solid intraductal echoes and wall thickening, five with inhomogeneous parenchyma). Galactography was negative in three patients and positive in nine. Nineteen patients were followed up by clinical examination, ultrasonography, and cytological evaluation of nipple discharge (6–12 months); three patients underwent excisional biopsy, ten core biopsy and 12 cytological biopsy (followed by excisional biopsy).ResultsMRI identified 25 enhancing lesions Breast Imaging Reporting and Data Systems (BI-RADS) 3 or 4) and confirmed the galactographic findings (ductal ectasia, intraluminal filling defects). Five papillomatoses appeared as patchy, homogeneous enhancing areas, 15 intraductal papillomas as areas with well-defined margins and type II time-intensity curves, and two atypical ductal hyperplasias as diffuse nodular enhancement. One micropapillary ductal carcinoma in situ (DCIS), one papillary carcinoma and one infiltrating ductal carcinoma (IDC) were visualised as two segmental areas of enhancement and one mass-like enhancement with poorly defined margins (BI-RADS 4). The follow-up was negative, showing no pathological enhancement (BI-RADS 1) in 12 patients and benign enhancement (BI-RADS 2) in seven.ConclusionsBreast MRI can be considered a valuable examination in the diagnosis of suspected ductal disease and an alternative to galactography when the latter cannot be used.RiassuntoObiettivoValutare il ruolo della risonanza magnetica (RM) in pazienti con secrezione monorifiziale dal capezzolo.Materiali e metodiQuarantaquattro pazienti con secrezione ematica/sieroematica dal capezzolo, mammografia negativa (35/44 casi) si sottoponevano allo studio dei dotti con RM. L’ecografia negativa in 18 casi, identificava ectasia duttale in 26: semplici in 12, con proliferazione solida intraduttale ed ispessimento parietale in 9 e con disomogeneità ghiandolare in 5; la galattografia negativa in 3 e positiva in 9. Diciannove pazienti effettuavano follow-up clinico, radiologico, citologico della secrezione (6–12 mesi), 3 biopsia chirurgica, 10 core-biopsy e 12 prelievo citologico (seguite da biopsia chirurgica).RisultatiRM identificava 25 aree di potenziamento classificate BI-RADS 3 o 4. Nelle pazienti sottoposte a galattografia, la RM riconosceva i reperti galattografici (ectasia o difetti di riempimento). Cinque papillomatosi duttali si identificavano come potenziamento lineare ed omogeneo; 15 papillomi: enhancement a margini netti e curva intensità-tempo di tipo II, 2 iperplasie duttali atipiche: potenziamento nodulare diffuso. Un carcinoma papillare, 1 CDIS con aspetto micropapillare e 1 CDI si evidenziavano come 2 aree di potenziamento segmentale e un’area di potenziamento nodulare a margini irregolari (BI-RADS4). Follow-up negativo in 12 pazienti senza potenziamento patologico (BI-RADS1) e in 7 con potenziamento benigno (BIRADS2).ConclusioniLa RM può essere considerata valida metodica diagnostica nello studio della sospetta patologia duttale con secrezione, in alternativa alla galattografia quando questa metodica non sia utilizzabile.

Breast MRI: Are T2 IR sequences useful in the evaluation of breast lesions?

AIM To evaluate the potential role of signal intensities calculated in T2 images as an adjunctive parameter in the analysis of mass-like enhancements classified as BIRADS (Breast Imaging Reporting and Data System) assessment categories 2, 3, 4 or 5 with the standard T1 criteria. MATERIALS AND METHODS After a retrospective review of 338-breast Magnetic Resonance Imaging (MRI) performed for the evaluation of a suspicious lesion we selected a group of 65 mass-like enhancements ranging from 5 to 20mm, classified as BIRADS assessment categories 2, 3, 4 or 5, histologically proved. In all cases we calculated the ratio between the signal intensity (SI) of the nodule and the pectoralis major muscle (LMSIR, lesion to muscle signal intensity ratio) with a multiROIs (region of interest) analysis on T2 images. A ROC analysis was performed to test the ability of the two diagnostic parameters separately considered (BIRADS and LMSIR) and combined in a new mono-dimensional variable obtained by a computerized discriminant function. RESULTS Histological examination assessed 34 malignant lesions (52.3%) and 31 benign lesions (47.7%). The evaluation of ROC curves gave the following results: BIRADS area under the curve (AUC) 0.913, S.E. 0.0368, LMSIR AUC 0.854, S.E. 0.0487, combined BIRADS-LMSIR AUC 0.965, S.E. 0.0191 with a definitive increase in the AUC between the overall ROC area and those of the two diagnostic modalities separately considered. DISCUSSION T2-weighted SI assessment with LMSIR measurement improves the diagnostic information content of standard breast MRI and can be considered a promising potential tool in the differential diagnosis of mass-like enhancements judged as borderline lesions (BIRADS 3 and 4).

Diagnostic utility of combined ultrasonography and mammography in the evaluation of women with mammographically dense breasts

PURPOSE To assess the diagnostic utility and additional cost of combined breast ultrasonography and mammography in the evaluation of asymptomatic women with mammographically dense breasts. MATERIALS AND METHODS Of 5108 asymptomatic women, who underwent mammography, 1754 had dense breasts (BI-RADS 3 or 4) and negative mammographic outcome. They were divided in 4 subgroups according to their age (<40 yrs; 40-49 yrs; 50-59 yrs; >59 yrs). Breast ultrasonography was performed immediately after mammography. Lesions detected at ultrasonography were examined cytologically/histologically. Mammograms from women, who were diagnosed carcinoma at ultrasonography, were reviewed by an external radiologist. Costs per diagnosed carcinoma and per examined woman were calculated on the basis of current regional charges. RESULTS Mammographies (5108) were performed, 67 cancers were detected (cancer detection rate 13.1‰): mammography identified 55 carcinomas and ultrasonography performed in women with dense breasts identified 12 cancers (17.9% of all cancers detected, overall cancer detection rate 6.8‰). Ultrasonography identified a benign condition in 1567 out of 1754 women (89.3%) (in 925 absence of focal lesions; 438 simple cysts; 56 ductal ectasia; 148 benign solid lesions); 97 complex cysts, 52 lesions that could not be differentiated as liquid or solid lesions, and 38 solid lesions suspicious for malignancy in the remaining 187 out of 1754 patients (10.7%). Cytology/histology confirmed carcinoma in 12 women (overall biopsy rate 26.2‰, benign biopsy rate 19.4‰). The additional costs were: € 6,123.45 per detected cancer, € 41.89 per examined woman. CONCLUSION Breast ultrasonography immediately after mammography in women with dense breasts is useful to avoid diagnostic delays and inconvenient medico-legal implications even though this procedure involves increased costs.

Fetal MRI with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) assessment in the evaluation of renal development: preliminary experience in normal kidneys

PurposeThe study aimed to investigate the correlation between apparent diffusion coefficient (ADC) and gestational age by applying diffusion-weighted imaging (DWI) in the study of normal fetal kidneys.Materials and methodsWe performed magnetic resonance (MR) imaging on 88 fetuses (gestational age range 17–40 weeks) after ultrasound had ruled out urinary system malformations. A multiplanar study of the urinary system was obtained by using conventional T2-weighted sequences and echoplanar imaging (EPI). DW sequences with ADC maps were subsequently acquired, and kidney ADC values were correlated with gestational age by diving the fetuses into six groups according to age.ResultsWe found a correlation between ADC values and gestational age. The ADC values, ranging from 0.99 to 1.62×10−3 mm2/s [mean 1.22; 95% confidence interval (CI) 1.19–1.25, standard deviation (SD) 0.147], showed a tendency to decrease with increasing gestational age. The relationship between ADC values and gestational age was expressed by a linear regression equation: ADC (mm2/s)=1.69–0.0169 (GA) (R2=37.7%, R2 ADJ=37.0%, p<0.005, Pearson correlation=−0.614).ConclusionsDWI with ADC mapping provides functional information on fetal renal parenchyma development and may thus become a useful tool in the management of pregnancy and treatment of the newborn child.RiassuntoObiettivoApplicare le sequenze pesate in diffusione (DWI) nello studio dei reni fetali, per valutare l’esistenza di una correlazione fra coefficiente di diffusione apparente (ADC) ed età gestazionale nei feti sani.Materiali e metodiAbbiamo studiato con esame RM 88 feti (età gestazionale 17–40 settimane), già valutati con esame ecografico che escludeva malformazioni del tratto urinario. L’apparato urinario fetale è stato studiato con sequenze T2 pesate ultraveloci; successivamente sono state acquisite sui reni fetali sequenze DWI (con calcolo automatico delle mappe di ADC) ed i valori di ADC messi in relazione con l’età gestazionale, suddividendo i feti in sei gruppi in base all’età gestazionale. La normale funzionalità renale è stata confermata dopo la nascita attraverso dati clinico-laboratoristici ed ecografia renale.RisultatiAbbiamo riscontrato che i valori di ADC, compresi fra 0,99 e 1,62×10−3 mm2/s (media 1,22; 95% CI 1,19–1,25; deviazione standard 0,147) tendono a decrescere con l’aumentare delle settimane di gestazione. La migliore correlazione è stata espressa dall’equazione di regressione lineare: ADC (mm2/s)=1,69–0,0169 (GA) (R2=37,7%, R2 ADJ=37,0%, p<0,005, correlazione di Pearson=–0,614). Conclusioni. Le sequenze DWI ed le mappe di ADC, fornendo informazioni funzionali sullo sviluppo del parenchima renale fetale, risultano di grande utilità soprattutto nella gestione della gravidanza e nel management post-natale.