18F-FDG PET/CT IN DIFFERENTIATED THYROID CARCINOMA.

AIM: Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) become an important tool in oncology by combining the metabolic information from 18F-FDG PET with the morphological information of CT. The main objective of this study was to assess the diagnostic value of PET/CT in patients with differentiated thyroid carcinoma (DTC). MATERIAL AND METHODS: We analyzed 173 PET/CT scans of patients with DTC presenting elevated thyroglobulin (Tg) levels, negative Tg-antibodies levels, negative Iodine-131 whole-body scanning (I-131 WBS) and without any signs of clinical or other imaging technique for tumor recurrence/metastases. RESULTS: PET/CT scans were positive in 38% of cases (65/173). The sensitivity, specificity, positive predictive values and the accuracy of PET/CT imaging were 88.09%, 98.6%, 93.1% respectively 96.53%. After the PET/CT scan 29 patients underwent surgery, 24 of them continued radio-iodine therapy, 5 patients initiated tyrosine kinase inhibitors treatment and external radiotherapy. CONCLUSION: 18F-FDG PET/CT is a valuable imaging technique which has the capability of identifying those cases of thyroid recurrence/metastases with elevated Tg levels and negative I-131 WBS. The treatment strategy was changed in 89.2% cases of positive PET/CT scans which shows us that 18F-FDG PET/CT imaging should be integrated into the follow-up programs for DTC patients.

Flap warming improves intraoperative indocyanine green angiography (ICGA) assessment of perfusion. An experimental study.

BACKGROUND: Indocyanine green angiography (ICGA) is slowly replacing conventional methods of evaluating perfusion during flap surgery. Microcirculatory changes during flap elevation create a marked state of hypoperfusion intraoperatively leading to ICGA underestimation of tissue viability and consequent resection of viable tissue. We propose a novel method of flap warming to induce maximum vasodilation before performing ICGA to increase accuracy in assessing perfusion. METHODS: Submental flaps harvested on a single perforator were created in 8 pigs. ICG angiography was performed in the intraoperative phase (ICGA-C), after inducing maximum vasodilatation by warming the flap at 42 °C (ICGA-W) and at 24H postoperative (ICGA-24). By setting a fluorescence threshold of 33% as indicative of necrosis, the flap surface deemed viable by ICGA was measured for ICGAC, ICGAW and ICGA24. The results were then compared to the actual flap survival observed clinically at 7 days. RESULTS: The mean of ICG-C predicted flap survival (FS-C = 49.17%) is 12.97% lower than the mean of actual flap survival on postoperative day 7 (FS = 62.14%). The mean difference between ICG-W and ICG-24 predicted flap survival (FS-W and FS-24) and actual flap survival in the postoperative day 7 (FS) is lower, 3.13% and 2.15%, respectively. Average perfusion recovery over 24 h was 10.83% (FS-24-FS-C). CONCLUSIONS: Conventional intraoperative ICGA underestimated perfusion in all cases. Warming the flap intraoperatively and achieving maximum vasodilation mitigates the effects of vasoconstriction and mimics the microcirculatory environment encountered at 24 h. Performing angiography after induced vasodilation improves ICGA assessment of flap perfusion.

Skin wound regeneration with bioactive glass-gold nanoparticles ointment.

The bioactive glasses can lead to the promotion of growth of granulation tissue, while the gold nanoparticles (AuNPs) can induce the acceleration of wound healing including tissue regeneration, connective tissue formation, and angiogenesis. The aim of this study was to evaluate the impact of using the bioactive glass (BG) and BG-AuNPs composites on skin wound healing in experimental rat models for 14 days. Sol-gel derived BGs and BG-AuNPs composites mixed with Vaseline at 6, 12 and 18 wt% were used to evaluate the repair response of the skin. During the process of healing, granulomatous reaction was observed in the wound treated with 12 and 18 wt% BG-Vaseline ointments. Furthermore, a strong vascular proliferation and complete wound regeneration were found in 18%BG-AuNPs-Vaseline treated groups. The results derived from the performed investigations revealed that the 18% BG-AuNPs-Vaseline ointment is a promising candidate for wound healing applications.

EVALUATION OF CARDIOVASCULAR RISK AND MYOCARDIAL PERFUSION IN PATIENTS WITH RADICALLY TREATED DIFFERENTIATED THYROID CARCINOMA AND REPEATED EPISODES OF IATROGENIC HYPOTHYROIDISM.

CONTEXT: Patients with radically treated differentiated thyroid carcinoma (DTC) undergo multiple episodes of iatrogenously-acquired hypothyroidism for the oncological follow-up. In some patients, this elevates high-sensitive C-reactive protein (hsCRP), a cardiovascular risk biomarker. OBJECTIVE: We wanted to determine if there is any correlation between repeated hypothyroidism episodes, elevated hsCRP and an increased cardiovascular risk as stated through myocardial perfusion. DESIGN: Between July 2014-January 2015, we analyzed serological levels of hsCRP for identifying our patients' cardiovascular risk; we performed a myocardial perfusion scintigraphy to observe the alterations. SUBJECTS AND METHODS: We included 27 patients (n=27), mean age of 52±10: CI (95%),14 female, all disease- free after thyroidectomy, radioiodine ablation and chronic thyroid hormone treatment. We assigned the cardiovascular risk category for each patient according to hsCRP levels; all patients underwent a myocardial perfusion scintigraphy in order to determine the cardiac perfusion index (CPI). RESULTS: hsCRP has been higher in > 65 years old male patients with more than 5 thyroid hormone withholdings. hsCRP is significantly associated with CPI (p=0.001). Spearman's rank correlation indicates a strongly positive linear correlation between these two parameters (r=0.745). CONCLUSIONS: Repeated thyroid hormonal withdrawals in patients with DTC during the long-term follow-up elevated hsCRP at cardiovascular risk levels, having an impact on myocardial perfusion.

The effect of chronic toxicity of pethidine on the spinal cord: an experimental model in rabbits.

The aim of this study was to evaluate the toxicity of chronic spinal analgesia with pethidine in a rabbit model. We introduced epidural catheters in twenty New Zealand white rabbits, divided into two groups, and we administered 0.5 mg/kg pethidine or the same volume of normal saline through the catheters, for three consecutive days. Throughout the experiment, the animals were evaluated in terms of neurological status using the Tarlov score. After the rabbit's euthanasia, 4 µm sections of spinal cord stained with Hematoxylin-Eosin were analyzed by a pathologist blinded to the study for neurohistopathological changes. The results were statistically analyzed with Prism 5 software for Windows. No significant differences were noticed between the two groups in as far as body temperature (p=0.295) and weight (p=0.139) were concerned. In the group of animals, which received epidural pethidine, nine rabbits showed histological changes suggestive for neurotoxicity at the lumbar level of the spinal cord. These findings were significantly different compared with the control group which received only saline (no microscopic lesions revealed; p=0.0006). When combining the data from both groups or using the pethidine group alone, there was a significant correlation between the presence of neurological injury (Tarlov score) and the presence of the histopathological lesions in the spinal cord (r=-0.709, p=0.0002 and r=-0.635, p=0.013, respectively). Based on our findings, the chronic epidural administration of pethidine in rabbits induces moderate to severe histological changes on the spinal cord, but further investigations are needed to make a definitive statement about the histological effect of pethidine on the neurological tissue.

The effect of distraction rate on bone histological and histomorphometrical properties in an ovine mandible model.

UNLABELLED: Lengthening the mandible by distraction osteogenesis (DO) is nowadays a well-recognized technique in maxillofacial surgery. This study compared two different distraction rates and evaluated histological and histomorphometrical properties of the distracted bone in an experimental ovine mandible model with the goal of elaborating a universally accepted distraction protocol. STUDY DESIGN: Tissue blocks of regenerated bone were harvested from twelve young adult sheep. DO was performed on the mandibular midline after five days of latency period. The sheep were divided into two groups. The first group underwent activation of 0.8 mm÷day during 12 days resulting in 9.6 mm of new bone while the second group followed a geometric rate pattern of 0.2 mm - three days, 0.4 mm - three days, 0.8 mm - three days and 1.6 mm - three days resulting in 9 mm of new bone. The regenerated bone was histologically and histomorphometrically analyzed after 30, 45 and 60 days of consolidation. The relative osteoid volume (OV÷TTV) was significantly increased in the geometric rate distraction group (p=0.015) comparing with linear distraction group while the relative bone volume (BV÷TTV) was significantly increased in the linear distraction group (p=0.019) compared to the geometric distraction group.