Aleksi Schrey

Ultrasonically activated scalpel compared with electrocautery in tonsillectomy.

The occurrence of postoperative bleeding, the quantity of operative bleeding and the duration of operation were retrospectively evaluated in 407 patients who underwent tonsillectomy within a 32-month period. They were operated on with either an ultrasonically activated scalpel (UAS), bipolar diathermy (BPD) or blunt dissection with monopolar diathermy (MPD) with the following results. (1) Primary bleeding was more common with MPD: MPD 7.1% vs. BPD 2.4% (p < 0.01) vs. UAS 1.0% (p < 0.001). Secondary bleeding was more common with UAS: UAS 19.6% vs. MPD 14.5% (p < 0.001) vs. BPD 14.5% (p < 0.01). There was no statistical significance in the differences between overall postoperative bleeding rates. (2) There was statistically significantly less operative bleeding with UAS:UAS 24.8 ml vs. MPD 58.7 ml vs. BPD 43.8 ml. (3) On the other hand, the operation time was on average longer with UAS: UAS 32.3 min vs. MPD 18.4 min vs. BPD 22.1 min. Our results suggest that UAS offers no significant advantage over MPD or BPD in tonsillectomy other than minimal operative bleeding possibly due to longer duration of operation.

Fast growth associated with aberrant vasculature and hypoxia in fibroblast growth factor 8b (FGF8b) over-expressing PC-3 prostate tumour xenografts

BackgroundProstate tumours are commonly poorly oxygenated which is associated with tumour progression and development of resistance to chemotherapeutic drugs and radiotherapy. Fibroblast growth factor 8b (FGF8b) is a mitogenic and angiogenic factor, which is expressed at an increased level in human prostate tumours and is associated with a poor prognosis. We studied the effect of FGF8b on tumour oxygenation and growth parameters in xenografts in comparison with vascular endothelial growth factor (VEGF)-expressing xenografts, representing another fast growing and angiogenic tumour model.MethodsSubcutaneous tumours of PC-3 cells transfected with FGF8b, VEGF or empty (mock) vectors were produced and studied for vascularity, cell proliferation, glucose metabolism and oxygenation. Tumours were evaluated by immunohistochemistry (IHC), flow cytometry, use of radiolabelled markers of energy metabolism ([18F]FDG) and hypoxia ([18F]EF5), and intratumoral polarographic measurements of pO2.ResultsBoth FGF8b and VEGF tumours grew rapidly in nude mice and showed highly vascularised morphology. Perfusion studies, pO2 measurements, [18F]EF5 and [18F]FDG uptake as well as IHC staining for glucose transport protein (GLUT1) and hypoxia inducible factor (HIF) 1 showed that VEGF xenografts were well-perfused and oxygenised, as expected, whereas FGF8b tumours were as hypoxic as mock tumours. These results suggest that FGF8b-induced tumour capillaries are defective. Nevertheless, the growth rate of hypoxic FGF8b tumours was highly increased, as that of well-oxygenised VEGF tumours, when compared with hypoxic mock tumour controls.ConclusionFGF8b is able to induce fast growth in strongly hypoxic tumour microenvironment whereas VEGF-stimulated growth advantage is associated with improved perfusion and oxygenation of prostate tumour xenografts.

The limitations of tissue-oxygen measurement and positron emission tomography as additional methods for postoperative breast reconstruction free-flap monitoring

Twelve patients who underwent breast reconstruction with a microvascular flap were monitored postoperatively with continuous partial tissue oxygenation (p(ti)O(2)) measurement. The regional blood flow (BF) of the entire flap was evaluated with positron emission tomography (PET) using oxygen-15-labelled water on the first postoperative (POP) morning to achieve data of the perfusion of the entire flap. A re-exploration was carried out if the p(ti)O(2) value remained lower than 15 mmHg for over 30 min. The mean p(ti)O(2) value of the flaps was 52.9+/-5.5 mmHg, whereas the mean BF values were 3.3+/-1.0 ml per 100 g min(-1). One false-positive result was detected by p(ti)O(2) measurement, resulting in an unnecessary re-exploration. Another re-operation suggested by the low p(ti)O(2) results was avoided due to the normal BF results assessed with PET. Totally, three flaps were re-explored. This prospective study suggests that continuous tissue-oxygen measurement with a polarographic needle probe is reliable for monitoring free breast flaps from one part of the flap, but assessing perfusion of the entire flap requires more complex monitoring methods, for example, PET. Clinical examination by experienced personnel remains important in free-breast-flap monitoring. PET could be useful in assessing free-flap perfusion in selected high-risk patients as an alternative to a re-operation when clinical examination and evaluation by other means are unreliable or present controversial results.

Botulinum toxin alleviates dysphagia of patients with inclusion body myositis

OBJECTIVES Oropharyngeal dysphagia is a disabling and undertreated symptom that often occurs in patients with sporadic inclusion body myositis (s-IBM). In this study, we examined the effect of botulinum neurotoxin A (BoNT-A) injections to the cricopharyngeus muscle (CPM) of patients with s-IBM and dysphagia. PATIENTS, MATERIALS AND METHODS A single-center retrospective study involving 40 biopsy-proven s-IBM-patients treated in the District of Southwest Finland from 2000 to 2013. The incidence of dysphagia, rate of aspirations, rate of aspiration pneumonias and treatment results of dysphagia were analyzed. Patients treated for dysphagia were evaluated before and after surgery by video-fluoroscopy and/or using a questionnaire. RESULTS Twenty-five of the 40 s-IBM patients (62.5%) experienced dysphagia. BoNT-A was injected a median of 2 times (range 1-7) in 12 patients with dysphagia. Before the injections 7 patients reported aspiration, none afterwards. The corresponding figures for aspiration pneumonia were 3 and 0. All of these patients had normal swallowing function 12months (median, range 2-60) after the last injection. CONCLUSION BoNT-A injections to the CPM alleviate the dysphagia of s-IBM patients reversibly and appear to reduce the rate of aspiration effectively.

Evaluation of repeated [18F]EF5 PET/CT scans and tumor growth rate in experimental head and neck carcinomas

BackgroundTumor hypoxia is linked to invasion and metastasis but whether this associates with tumor growth rate is not well understood. We aimed to study the relationship between hypoxia evaluated with the positron emission tomography (PET) tracer [18F]EF5 and tumor growth. Our second goal was to assess the variability in the uptake of [18F]EF5 in tumor between two scans.MethodsFour human head and neck squamous cell carcinoma (UT-SCC) cell lines were xenografted in flank or neck of nude mice, and tumor size was closely monitored over the study period. The tumors were clearly visible when the first [18F]EF5 scan was acquired. After an exponential growth phase, the tumors were imaged again with [18F]EF5 and also with 18F-fluorodeoxyglucose ([18F]FDG).ResultsThere was a clear correlation between the percentage of tumor growth rate per day and the [18F]EF5 uptake in the latter scan (r = 0.766, p = 0.01). The uptake of [18F]EF5 in the first scan and the uptake of [18F]FDG did not significantly correlate with the tumor growth rate. We also observed considerable variations in the uptake of [18F]EF5 between the two scans.ConclusionsThe uptake of [18F]EF5 in the late phase of exponential tumor growth is associated with the tumor growth rate in mice bearing HNC xenografts.

Toll-like receptor 9 expression is associated with breast cancer sensitivity to the growth inhibitory effects of bisphosphonates in vitro and in vivo

Bisphosphonates are standard treatments for bone metastases. When given in the adjuvant setting, they reduce breast cancer mortality and recurrence in bone but only among post-menopausal patients. Optimal drug use would require biomarker-based patient selection. Such biomarkers are not yet in clinical use. Based on the similarities in inflammatory responses to bisphosphonates and Toll-like receptor (TLR) agonists, we hypothesized that TLR9 expression may affect bisphosphonate responses in cells. We compared bisphosphonate effects in breast cancer cell lines with low or high TLR9 expression. We discovered that cells with decreased TLR9 expression are significantly more sensitive to the growth-inhibitory effects of bisphosphonates in vitro and in vivo. Furthermore, cancer growth-promoting effects seen with some bisphosphonates in some control shRNA cells were not detected in TLR9 shRNA cells. These differences were not associated with inhibition of Rap1A prenylation or p38 phosphorylation, which are known markers for bisphosphonate activity. However, TLR9 shRNA cells exhibited increased sensitivity to ApppI, a metabolite that accumulates in cells after bisphosphonate treatment. We conclude that decreased TLR9-expression sensitizes breast cancer cells to the growth inhibitory effects of bisphosphonates. Our results suggest that TLR9 should be studied as a potential biomarker for adjuvant bisphosphonate sensitivity among breast cancer patients.

Blood pressure and free flap oxygenation in head and neck cancer patients

Abstract Conclusion: This study suggests that although oxygen partial pressure in tissue (p tiO2) measurement is a feasible method for continuous postoperative monitoring of free flaps, low correlation between blood pressure (BP) and p tiO2 might predict compromised overall outcome. Thus, it is of utmost importance to keep the BP optimal for adequate perfusion of re-anastomosed tissue transfers. Objective: Optimal BP is an important factor in assuring adequate blood flow in a free flap. Tissue oxygenation in free flaps as a postoperative monitoring target is in routine clinical use in some clinics. Correlation between p tiO2 and systemic BP was investigated. Methods: Ten consecutive patients underwent resection of head and neck squamous cell carcinoma followed by microvascular reconstruction with a free microvascular flap. P tiO2 of each flap was continuously monitored for 3 postoperative days with a polarographic measurement system. BP was measured invasively and continuously during the operation and during the first postoperative day at the intensive care unit. The correlation coefficient between p tiO2 and BP was analysed. Results: The correlation coefficient between p tiO2 and BP was relatively high in all patients with uneventful flap survival (r mean = 0.63, n = 5). In flaps with haemodynamic problems or compromised flap vitality the correlation appeared low (r mean = –0.02, n = 5).

The feasibility of NBI in patients with suspected upper airway lesions: A multicenter study

Narrow band imaging (NBI) improves diagnosis of laryngopharyngeal cancer, but most reported NBI studies are from experienced centers. Feasibility reports on use at everyday outpatient departments are needed.

Changes in blood flow in the epigastric free flap after microsurgical artery anastomoses in rats.

A number of clinical disorders of free vascularized flap are presumed to reflect insufficient blood flow (BF) or an inadequate range of vascular responsiveness. We compared the changes in BF in a pedicled and free epigastric flap, directly after and 90 min after performing microsurgical artery anastomoses. We used the clamping method and laser Doppler flowmetry in six Sprague-Dawley rats. The BF response curves shortly after re-anastomosing of the artery differ markedly from those in a pedicled flap model and curves registered 90 min after performing the anastomosis. We conclude that the clamping method is reliable and reproducible when studying the short-term autoregulatory BF patterns of epigastric pedicled and free flaps.A number of clinical disorders of free vascularized flap are presumed to reflect insufficient blood flow (BF) or an inadequate range of vascular responsiveness. We compared the changes in BF in a pedicled and free epigastric flap, directly after and 90 min after performing microsurgical artery anastomoses. We used the clamping method and laser Doppler flowmetry in six Sprague-Dawley rats. The BF response curves shortly after re-anastomosing of the artery differ markedly from those in a pedicled flap model and curves registered 90 min after performing the anastomosis. We conclude that the clamping method is reliable and reproducible when studying the short-term autoregulatory BF patterns of epigastric pedicled and free flaps.