We compared the detection rate (DR) for sentinel lymph nodes (SLN_S), the number of SLNs and the subjects with additional SLNs of single-photon emission computed tomography (SPECT/CT) and planar lymphoscintigraphy (PL) in patients with melanoma. Furthermore, we evaluated the impact of SPECT/CT on surgical plans. Articles containing head-to-head comparisons between SPECT/CT and PL were searched in Pubmed/MEDLINE and Scopus. The literature search was updated until December 31st, 2019. DR was calculated on a per-patient-based analysis; the studies were pooled by their odds ratios (ORs) with a random effects model to assess the significance of difference (p < 0.05). The number of additional SLNs (calculated as the relative risk) and pooled proportion of patients with additional SLNs were investigated. The pooled ratio of surgical procedures influenced by the SPECT/CT findings was calculated. Seventeen studies with 1438 patients were eligible for the calculation of DR of SPECT/CT and PL. The average DR was 98.28% (95% confidence interval (95% CI): 97.94–99.19%) for the SPECT/CT and 95.53% (95% CI: 92.55–97.77%) for the PL; OR of 2.31 (95% CI: 1.66–4.18, p < 0.001) in favor of the SPECT/CT. There was a relative risk of a higher number of SLNs (1.13) for the SPECT/CT and 17.87% of patients with additional SLNs were detected by SPECT/CT. The average impact of SPECT/CT on surgery resulted in 37.43% of cases. This meta-analysis favored SPECT/CT over PL for the identification of SLNs in patients with melanoma due to a higher DR, reproducibility, number of SLNs depicted, proportion of patients with additional SLNs and the impact on the surgical plan. However, PL remains a good option due to the high values of the DR for SLNs.

The aim of this study was to compare reported results on available techniques for sentinel lymph node detection rate (SDR) in papillary thyroid cancer (PTC). The MEDLINE database was searched via a PubMed interface to identify original articles regarding sentinel lymph node biopsy (SNB) in thyroid cancer. Studies were stratified according to the sentinel lymph node (SLN) detection technique: vital-dye (VD), 99mTc-nanocolloid planar lymphoscintigraphy with the use of intraoperative hand-held gamma probes (LS), both 99mTc-nanocolloid planar lymphoscintigraphy with intraoperative use of hand-held gamma probe and VD (LS + VD), 99mTc-nanocolloid planar lymphoscintigraphy with the additional contribution of preoperative SPECT/CT, and intraoperative use of hand-held gamma probe (LS-SPECT/CT). Pooled SDR values were presented with a 95% confidence interval (CI) for each SLN detection techniques. A Z-test was used to compare pooled SDR estimates. False-negative rates were summarized for each method. Forty-five studies were included. Overall SDRs for the VD, LS, LS + VD, and LS-SPECT/CT techniques were 83% (95% CI, 77%–88%; I2 = 78%), 96% (95% CI, 90%–98%; I2 = 68%), 87% (95% CI, 65%–96%; I2 = 75%), and 93% (95% CI, 86%–97%; I2 = 0%), respectively. False-negative rates were 0% to 38%, 0% to 40%, 0% to 17%, and 7% to 8%, respectively. In patients with PTC, 99mTc-nanocolloids offer a higher SDR than that of the VD technique. The addition of SPECT/CT improved identification of metastatic SLNs outside the central neck compartment.

Purpose: The clinical introduction of a radioactive and fluorescent hybrid tracer allowed for preoperative lymphatic mapping and intraoperative real-time fluorescence tracing of the sentinel lymph node (SLN) by a single injection. The aim of this feasibility study is to evaluate the first-in-human use of the hybrid tracer by combining indocyanine green (ICG) and radiocolloid based on Nanotop compound (^99mTc Nanotop) for SLN biopsy (SLNB) in breast cancer patients. Methods: The day before surgery, ICG-^99mTc Nanotop was injected periareolarly in breast cancer patients scheduled for SLNB. Planar lymphoscintigraphic (PL) and SPECT/CT images were then acquired. An intraoperative optonuclear probe was used to detect SLN gamma and fluorescent signals. The harvested SLNs were examined by hematoxylin-eosin staining, and patients were clinically evaluated 1 month after surgery. Results: Twenty-one consecutive patients were enrolled. The PL and SPECT/CT techniques identified at least 1 SLN in all patients for a preoperative sentinel detection rate of 100%. SPECT/CT revealed 3 additional lymph nodes in the same nodal basin, which had not been visualized on conventional PL (κ = 0.747; P < 0.005). All 30 preoperative SLNs were localized and excised up to 16 hours after injection. The counts measured via gamma tracing showed a very strong correlation with those measured via near-infrared fluorescent tracing (P < 0.005, r = 0.964). No adverse reactions were observed. Conclusions: The SLNB technique used with the ICG-^99mTc Nanotop tracer resulted to be feasible, reliable, and safe. This hybrid compound allowed us to obtain excellent performance in terms of both preoperative lymphatic mapping and intraoperative SLN detection in breast cancer patients.

Background: Current magnetic resonance imaging (MRI) techniques for measuring extraocular muscle (EOM) volume enlargement are not ideally suited for routine follow-up of Graves’ ophthalmopathy (GO) because the difficulty of segmenting the muscles at the tendon insertion complicates and lengthens the study protocol. Purpose: To measure the EOM sampled volume (SV) and assess its correlation with proptosis. Material and Methods: A total of 37 patients with newly diagnosed GO underwent 3-T MRI scanning with iterative decomposition of water and fat (IDEAL) sequences with and without contrast enhancement. In each patient, the three largest contiguous coronal cross-sectional areas (CSA) on the EOM slices were segmented using a polygon selection tool and then summed to compute the EOM-SV. Proptosis was evaluated with the Hertel index (HI). The relationships between the HI value and EOM-SV and between HI and EOM-CSA were compared and assessed with Pearson’s correlation coefficient and the univariate regression coefficient. Inter-observer and intra-observer variability were calculated. Results: HI showed a stronger correlation with EOM-SV ( P < 0.001; r = 0.712, r ² = 0.507) than with EOM-CSA ( P < 0.001; r = 0.645 and r ² = 0.329). The intraclass correlation coefficient indicated that the inter-observer agreement was high (0.998). The standard deviation between repeated measurements was 1.9–5.3%. Conclusion: IDEAL sequences allow for the measurement EOM-SV both on non-contrast and contrast-enhanced scans. EOM-SV predicts proptosis more accurately than does EOM-CSA. The measurement of EOM-SV is practical and reproducible. EOM-SV changes of 3.5–8.3% can be assumed to reflect true volume changes.