Imaging of Hypoxia in Liver Tumors With 18F-FMISO PET Before Selective Internal Radiotherapy With 90Y Microspheres.

ABSTRACT: Hypoxia is a known cause of resistance to radiotherapy and chemotherapy. Although there are multiple studies in external radiation therapies based on hypoxia PET, the effect of hypoxia in radioembolization is largely unknown. Here we present 2 cases of hepatocellular carcinoma patients from a prospective study with different lesion characteristics on pretreatment 18F-FMISO PET and varying responses on 18F-FDG PET.

The Role of 18F-FLT PET/CT in Assessing Early Response to Transarterial Radioembolization and Chemoembolization in Patients with Primary and Metastatic Liver Tumors.

Objectives: Metastases and primary malignancies are common in the liver. Local ablative applications such as transarterial chemoembolization (TACE), and transarterial radioembolization (TARE) provide minimally invasive and safe treatment in unresectable liver tumors. Early detection of response to treatment prevents unnecessary toxicity and cost in non-responder patients and provides an earlier use of other options that may be effective. This study aimed to identify the role of 18F-fluorothymidine (FLT) positron emission tomography/computed tomography (PET/CT) in the assessment of early response to TACE and TARE treatments in patients with unresectable primary and metastatic liver tumors. Methods: This single-center study included 63 patients who underwent 18F-FLT PET/CT for response evaluation after TACE and TARE. After excluding 20 patients whose data were missing 43 TARE-receiving patients were analyzed. The compatibility of change in semi-quantitative values obtained from the 18F-FLT PET/CT images with the treatment responses detected in 18F-fluorodeoxyglucose PET/CT, CT, and MR images and survival was evaluated. Results: There was no correlation between early metabolic, morphological response, and 18F-FLT uptake pattern, and change in standardized uptake values (SUV) which were ΔSUVmax, ΔSUVmean, ΔSUVpeak., ΔSUVmean, Δ SUVpeak values. There was no significant correlation between 18F-FLT uptake pattern, ΔSUVmax, ΔSUVmean, ΔSUVpeak, and overall survival, progression-free survival (PFS) for the target lobe PFS for the whole-body. The survival distributions for the patients with >30% change in Δ SUVmax and ΔSUVpeak values were statistically significantly longer than the patients with <30% change (p<0.009 and p<0.024, respectively). Conclusion: There was significant longer PFS for target liver lobe in patients with more than 30% decrease in 18F-FLT SUVmax and SUVpeak of the liver lesion in primary and metastatic unresectable liver tumors undergoing TARE.

Ultrasound-guided supraclavicular nerve block for implantable port catheters: Does it show a significant difference in pain control?

BACKGROUND: Nerve blocks have been used for decades at head and neck region interventions and recently introduced as an alternative option for subcutaneous port implantation. This study aimed to compare two different local anesthesia techniques used during subcutaneous port implantation. METHODS: This retrospective study was conducted with 107 patients who were categorized into two groups according to the local anesthesia techniques used during port implantations. Group 1 underwent local infiltration anesthesia and Group 2 received an ultrasound-guided supraclavicular nerve block. In both groups, prilocaine 2% was used for skin anesthesia and no other systemic anesthetic drugs or additional local anesthetics were administered during port implantation. Local anesthetic doses were 400 mg in Group 1 and 200 mg in Group 2. The time required for adequate cutaneous anesthesia, procedure time, complication rate and visual analog scale (VAS) score were recorded for each patient. RESULTS: Groups 1 and 2 contained 58 and 49 patients respectively. Both groups showed similar demographic distributions of patients (p > 0.05). Mean procedure times and the time required for adequate cutaneous anesthesia were longer in Group 2 (p < 0.05). Group 2 also showed 12 immediate complications, although they were temporary and recovered without any intervention under surveillance. Mean VAS scores during port implantation were similar in both groups [Group 1: 1.17(±0.60), Group 2: 1.1(±0.62)] (p > 0.05). CONCLUSIONS: The VAS scores did not differ significantly between groups. Although a supraclavicular nerve block may require lower local anesthetic doses for similar cutaneous anesthesia, it is associated with higher immediate complication rates due to unintended blockade of the peripheral nerves. Thus, if the nerve block is preferred over local infiltration anesthesia during port implantation, to prevent life-threatening complications, caution needed especially for the patients with contralateral vocal cord or diaphragm paralysis.

Scheduling surgery after transarterial embolization: does timing make any difference to intraoperative blood loss for renal cell carcinoma bone metastases?

PURPOSE: Our purpose is to clarify the optimal timing of surgery after transarterial embolization (TAE) for renal cell carcinoma (RCC) bone metastases. METHODS: This retrospective study included 41 patients with RCC bone metastases embolized between 2013 and 2019. Different-sized particulate and/or liquid embolic agents were used for TAE. Embolizations were categorized into groups 1-3 according to the interval between TAE and surgery (group 1: <1 day, group 2: 1-3 days, group 3: >3 days). Degree of embolization after TAE was graded visually based on angiographic images (<50%, 50%-75%, 75%-90%, >90%). The relationship between the TAE-surgery interval and intraoperative blood loss (IBL) and the correlation between IBL and embolization grade were examined. Lesion sizes and the relationships among lesion localizations and contrast media usage, intervention time, and IBL were also analyzed. RESULTS: Forty-six pre-operative TAEs (single lesion at each session) were performed in this study (26 in group 1, 13 in group 2, 7 in group 3). Lesion sizes and distributions were similar between groups (p = 0.897); >75% devascularization was achieved in 40 (TAEs 86.96%), but the IBL showed no correlation with the embolization rate (r=0.032, p = 0.831). The TAE-surgery interval was 1-7 days. The median IBL in group 1 (750 mL; range, 150-3000 mL) was significantly lower than those in the other groups (p = 0.002). Contrast media usage (p = 0.482) and intervention times (p = 0.261) were similar for metastases at different localizations. IBL values after TAE were lower for extremity metastases (p = 0.003). CONCLUSION: Bone metastases of RCC are well-vascularized, and to achieve lowest IBL values, surgery should preferably be performed <1 day after TAE.

Body Surface Area Is Not a Reliable Predictor of Tracheal Tube Size in Children.

OBJECTIVES: The age-based Cole formula has been employed for the estimation of endotracheal tube (ETT) size due to its ease of use, but may not appropriately consider growth rates among children. Child growth is assessed by calculating the body surface area (BSA). The association between the outer diameter of an appropriate uncuffed-endotrachealtube (ETT-OD) and the BSA values of patients at 24-96 months of age was our primary outcome. METHODS: Cole formula, BSA, age, height, weight and ultrasound measurement of subglottic-transverse-diameter were evaluated for correlations with correct uncuffed ETT-OD. The Cole formula, BSA, and ultrasound measurements were analyzed for estimation rates in all patients and age subgroups. The maximum allowed error for the estimation of ETT-OD was ≤0.3 mm. Patients' tracheas were intubated with tubes chosen by Cole formula and correct ETT-OD values were determined using leak test. ETT exchange rates were recorded. RESULTS: One-hundred twenty-seven patients were analyzed for the determination of estimation rates. Thirteen patients aged ≥72 months were intubated with cuffed ETT-OD of 8.4 mm and were accepted to need uncuffed ETT-OD >8.4 mm in order to be included in estimation rates, but excluded from correlations for size analysis. One-hundred fourteen patients were analyzed for correlations between correct ETT-OD (determined by the leak test) and outcome parameters. Cole formula, ultrasonography, and BSA had similar correct estimation rates. All three parameters had higher underestimation rates as age increased. CONCLUSION: The Cole formula, BSA, and ultrasonography had similar estimation rates in patients aged 24≤ to ≤96 months. BSA had a correct estimation rate of 40.2% and may not be reliable in clinical practice to predict uncuffedETT-size.

A comparison of basilar artery diameters measured by T2WI and TOF MR angiography.

PURPOSE: The purpose of our study is to compare basilar artery diameters (BAD) measured by T2WI to diameters measured by TOF MR angiography (MRA). By doing this, we hope to understand how compatible these two methodologies are with each other. METHODS: We used data from 100 patients (59 females, 41 males) who underwent a session of both T2W MRI and TOF MRA at the same time (ages between 18 and 83). We measured BAD by both T2WI and TOF MRA in three different levels. We then compared these diameters measured by two different methodologies to each other. RESULTS: In an area between the vertebrobasilar junction and posterior cerebral artery, all data measured by T2WI and TOF MRA in three different levels were analyzed. Average diameters measured by T2WI and TOF MRA turned out to be 79.5% correlated with each other. As a result of our mathematical model that we came up with through regression analysis, we calculated that measurements taken by T2WI on mid-pontine levels could predict TOF MRA measures with 78.3% accuracy. In T2WI and TOF MRA, average diameters measured were 2.982 ± 0.4717 and 3.205 ± 0.4281 mm, respectively. Statistical analyses showed that images measured by T2W series were significantly smaller than those measured by TOF MRA (p < 0.05). CONCLUSION: Our study showed that BAD measured by T2WI were smaller than those measured by TOF MRA. We think that it will be beneficial to refer our results to avoid T2WI and TOF MRA mismatch when evaluating BAD.