In this study the usefulness of parathyroid scintigraphy was evaluated in a group of patients affected by secondary hyperparathyroidism, combining the conventional double-tracer subtraction planar ...scintigraphy with pinhole-SPECT (P-SPECT) acquisition and comparing the scintigraphic data with those obtained by ultrasonography.
Twenty-four patients with secondary hyperparathyroidism were enrolled, 19 with chronic renal failure on haemodialysis and 5 with renal transplant. All patients underwent parathyroidectomy because of their unresponsiveness to medical therapy and/or severe osteodystrophy. Histology ascertained a single adenoma each in 3 patients and 61 hyperplastic glands in the remaining 21 cases. Before surgery, all patients were submitted to high resolution ultrasonography and afterwards to double-tracer subtraction planar parathyroid scintigraphy ((99m)Tc-pertechnetate/(99m)Tc-tetrofosmin) followed by neck P-SPECT acquisition.
P-SPECT was true positive in all 24 patients, while both planar and ultrasonography were false negative in one case. Globally, P-SPECT identified 60/64 hyperfunctioning parathyroid glands, planar 47/64 and ultrasonography 45/64. P-SPECT sensitivity (93.7%) was significantly higher than both planar (73.4%; p<0.001) and ultrasonography (70.3%; p< 0.0005). The difference was also significant (p<0.05) when P-SPECT sensitivity was compared with that obtained combining planar scintigraphy and ultrasonography (84.4%). Moreover, P-SPECT defined the exact number of hyperplastic glands in 85.7% of positive patients, while planar in 60% and ultrasonography in 45%. Only 4 hyperplastic glands were false negative at P-SPECT showing a maximum diameter of 10 mm and a weight ranging from 480 to 500 mg. These glands were also false negative at both planar scintigraphy and ultrasonography which missed further 13 and 15 hyperfunctioning glands, respectively, all detected by P-SPECT. Globally, the latter procedure gave the correct preoperative localization of hyperfunctioning parathyroid glands in 87.5%, planar in 62.5% and ultrasonography in 50%. None of the three procedures had false positive
The data of the present study seem to indicate that P-SPECT is a reliable diagnostic method in preoperative localization of hyperfunctioning parathyroid glands in patients with secondary hyperparathyroidism. This procedure identified a significantly higher number of hyperplastic glands than both double-tracer subtraction planar parathyroid scintigraphy and ultrasonography in our cases, thus proving a more useful guide for the surgeon. Given its low false negative rate, a wider use of P-SPECT is suggested in the preoperative management of patients with secondary hyperparathyroidism undergoing either a first operation of parathyroidectomy or a second operation for recurrence.
The aim of this study was to evaluate the usefulness of ^sup 99m^Tc-tetrofosmin single-photon emission tomography (SPET) in the detection of both primary breast cancer and axillary lymph node ...metastasis. We studied 192 consecutive patients in whom primary breast cancer was suspected on the basis of mammography and/or physical examination. After intravenous injection of 740 MBq ^sup 99m^Tc-tetrofosmin, both planar and SPET scintimammography was performed in all patients using a rectangular dual-head gamma camera equipped with low-energy, high-resolution, parallel-hole collimators. In 175 patients with breast cancer at histology, the per-lesion overall sensitivity of SPET and planar imaging for the detection of breast cancer was 95.8% and 75.9% (P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 96.5% and 79.5% in palpable (P<0.0005) and 90% and 45% in non-palpable lesions (P<0.01). With regard to lesion size, the sensitivity of SPET and planar imaging was, respectively, 90.5% and 45.2% in lesions ≤10 mm (P<0.0005), 95.3% and 81.4% in lesions of 11-20 mm (P<0.005), 100% and 84.6% in lesions of 21-30 mm (P<0.05) and 100% and 95.8% in lesions >30 mm (P>0.05). In the remaining 17 patients with benign mammary lesions at histology, per-lesion overall specificity of SPET and planar imaging was 76.2% and 85.7% (P>0.05), respectively. Neither SPET nor planar imaging showed false-positive results in non-palpable lesions or in those ≤10 mm. In 173 breast cancer patients submitted to axillary lymph node dissection (ALND), per-axilla overall sensitivity of SPET and planar imaging in the detection of axillary lymph node metastasis was 93% and 52.3% (P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 100% and 82.6% in palpable nodes (P>0.05), 90.5% and 41.3% in non-palpable nodes (P<0.0005), 92.8% and 35.7% in the presence of ≤3 nodes (P<0.0005) and 93.2% and 68.2% in the presence of >3 nodes (P<0.005). The specificity of SPET and planar imaging was 91% and 100% (P<0.05), respectively. ^sup 99m^Tc-tetrofosmin SPET appears to be a reliable method for the detection of both primary BC and axillary lymph node metastasis, and its diagnostic accuracy exceeds that of ^sup 99m^Tc-tetrofosmin planar scintimammography. The use of SPET is particularly important in the identification of small non-palpable primary carcinomas and metastatic axillae with ≤3 non-palpable lymph nodes. More extensive use of SPET appears warranted in the management of breast cancer patients.PUBLICATION ABSTRACT
1.
1. The regional cerebral blood flow was studied by SPECT in patients with partial epilepsy before and after 30 days of monotherapy with carbamazepine (CBZ).
2.
2. Both a qualitative visual ...interpretation and a semiquantitative analysis of SPECT was performed. All patients underwent EEG, CT scan, and MRI studies. The CBZ serum concentrations were assayed.
3.
3. After therapy, in three patients with focal epilepsy, both a crossed cerebral and cerebellar diaschisis were observed, with respect to the side of the epileptic focus in the opposite hemisphere. No morphologic changes were detected at MRI in the cerebral or cerebellar remote hypometabolic areas found at SPECT.
4.
4. CBZ may have a depressant action on the corticopontocerebellar pathways and on the corticocallosal connections.
PDF
