Single fraction radiosurgery using Rapid Arc for treatment of intracranial targets

<p>Abstract</p> <p>Background</p> <p>Stereotactic-Radio-Surgery (SRS) using Conformal-Arc-Therapy (CAT) is a well established irradiation technique for treatment of intracranial targets. Although small safety margins are required because of very high accuracy of patient positioning and exact online localisation, there are still disadvantages like long treatment time, high number of monitor units (MU) and covering of noncircular targets. This planning study analysed whether Rapid Arc (RA) with stereotactic localisation for single-fraction SRS can solve these problems.</p> <p>Methods</p> <p>Ten consecutive patients were treated with Linac-based SRS. Eight patients had one or more brain metastases. The other patients presented a symptomatic vestibularis schwannoma and an atypic meningeoma. For all patients, two plans (CAT/RA) were calculated and analysed.</p> <p>Results</p> <p>Conformity was higher for RA with additional larger low-dose areas. Furthermore, RA reduced the number of MU and the treatment time for all patients. Dose to organs at risk were equal or slightly higher using RA in comparison to CAT.</p> <p>Conclusions</p> <p>RA provides a new alternative for single-fraction SRS irradiation combining advantages of short treatment time with lower number of MU and better conformity in addition to accuracy of stereotactic localisation in selected cases with uncomplicated clinical realization.</p

Split Course Hyperfractionated Accelerated Radio-Chemotherapy (SCHARC) for patients with advanced head and neck cancer: Influence of protocol deviations and hemoglobin on overall survival, a retrospective analysis

BACKGROUND: The advantage of hyperfractionated accelerated radiation therapy for advanced head and neck cancer has been reported. Furthermore, randomized trials and meta-analyses have confirmed the survival benefit of additional chemotherapy to radiotherapy. We retrospectively analyzed the efficiency and toxicity of the Regensburg standard therapy protocol "SCHARC" and the overall survival of our patients. METHODS: From 1997 to 2004, 64 patients suffering from advanced head and neck cancer (88 % stage IV, 12 % stage III) were assigned to receive the SCHARC protocol. Around half of the patients were diagnosed with oro-hypopharynx carcinoma (52 %), one third with tongue and floor of mouth tumors (29 %) and one fifth (19 %) suffered from H & N cancer at other sites. The schedule consisted of one therapy block with 30 Gy in 20 fractions over a two week period with concomitant chemotherapy (d 1–5: 20 mg/m(2)/d DDP + 750–1000 mg/m(2)/d 5FU (cont. infusion). This therapy block was repeated after a fortnight break up to a cumulative dose of 60 Gy and followed by a boost up to 70 Gy (69–70.5 Gy). All patients assigned to this scheme were included in the survival evaluation. RESULTS: Forty patients (63 %) received both radiation and chemotherapy according to the protocol. The mean follow up was 2.3 years (829 d) and the median follow up was 1.9 years (678 d), respectively. The analysis of survival revealed an estimated 3 year overall survival rate of 57 %. No patient died of complications, 52 patients (80 %) had acute grade 2–3 mucositis, and 33 patients (58 %) suffered from acute grade 3 skin toxicity. Leucopenia was no major problem (mean nadir 3.4 g/nl, no patient < 1.0 g/nl) and the mean hemoglobin value decreased from 13.2 to 10.5 g/dl. Univariate analysis of survival showed a better outcome for patients with a hemoglobin nadir >10.5 g/dl and for patients who completed the protocol. CONCLUSION: The SCHARC protocol was effective in patients diagnosed with advanced head and neck cancer. It led to long-term disease control and survival in about 50 % of the patients with significant but acceptable toxicity. Most patients were not anemic at beginning of therapy. Therefore, we could assess the influence of pre-treatment hemoglobin on survival. However, a low hemoglobin nadir was associated with poor outcome. This result suggests an influence of anemia during therapy on prognosis

Long-term results of radiotherapy for periarthritis of the shoulder: a retrospective evaluation

<p>Abstract</p> <p>Background</p> <p>To evaluate retrospectively the results of radiotherapy for periarthritis of the shoulder</p> <p>Methods</p> <p>In 1983–2004, 141 patients were treated, all had attended at least one follow-up examination. 19% had had pain for several weeks, 66% for months and 14% for years. Shoulder motility was impaired in 137/140 patients. Nearly all patients had taken oral analgesics, 81% had undergone physiotherapy, five patients had been operated on, and six had been irradiated. Radiotherapy was applied using regular anterior-posterior opposing portals and Co-60 gamma rays or 4 MV photons. 89% of the patients received a total dose of 6 Gy (dose/fraction of 1 Gy twice weekly, the others had total doses ranging from 4 to 8 Gy. The patients and the referring doctors were given written questionnaires in order to obtain long-term results. The mean duration of follow-up was 6.9 years [0–20 years].</p> <p>Results</p> <p>During the first follow-up examination at the end of radiotherapy 56% of the patients reported pain relief and improvement of motility. After in median 4.5 months the values were 69 and 89%, after 3.9 years 73% and 73%, respectively. There were virtually no side effects. In the questionnaires, 69% of the patients reported pain relief directly after radiotherapy, 31% up to 12 weeks after radiotherapy. 56% of the patients stated that pain relief had lasted for "years", in further 12% at least for "months".</p> <p>Conclusion</p> <p>Low-dose radiotherapy for periarthropathy of the shoulder was highly effective and yielded long-lasting improvement of pain and motility without side effects.</p

Anaesth Crit Care Pain Med

INTRODUCTION: Dynamic arterial elastance (Eadyn) is defined as the ratio between pulse pressure variations (PPV) and stroke volume variations (SVV). Eadyn has been proposed to predict an increase in mean arterial pressure (MAP) after volume expansion with conflicting results. The aim of the present study was to test the reliability of Eadyn in hypotensive patients (MAP\textless65mmHg) in the operating room (OR). PATIENTS AND METHODS: The study pooled data from 51 patients. They were included after the induction of anesthesia and before skin incision. Eadyn, MAP and stroke volume (FloTracTM, VigileoTM, Edwards-Lifesciences, Irvine,CA) were recorded before and after volume expansion (500ml starch 6% given over 10minutes). Pressure-responders were defined as an increase MAP≥15% after volume expansion. Changes in MAP were predicted using the area under the curves (AUC) with their 95%Confidence Interval(95%CI) derived from Receiver Operating Characteristic curves. RESULTS: Seventeen patients responded to volume expansion. Heart rate, PPV, SVV and Eadyn were similar between pressure responders and non-responders. Baseline values of stroke volume, cardiac output and MAP were lower in responders. Volume expansion induced significant variations in stroke volume, cardiac output, SVV and PPV, but not in Eadyn. Baseline Eadyn failed to predict MAP increase (AUC=0.53,95%CI=0.36-0.70,P\textgreater0.05) and was not correlated with volume expansion-induced changes in MAP (P\textgreater0.05). In preload responsive patients (changes in SV≥15% after volume expansion,n=24), the AUC was 0.54(95%CI=0.29-0.78;P\textgreater0.05). CONCLUSION:In the present study performed in the OR and in hypotensive patients, Eadyn obtained using arterial signal was unable to predict an increase in MAP after volume expansion

Digital Shadows as an Enabler for the Internet of Production

Part 5: Cyber-Physical Production Systems and Digital TwinsInternational audienceDue to increasing atomization, manufacturing companies generate increasing amounts of production data. Most of this data is domain-specific, heterogeneous and unstructured. This complicates the access, interpretation, analysis and usage for efficiency improvement, faster reaction to change and weaknesses identification. To overcome this challenge, the idea of an “internet of production” is to link all kind of production relevant data by a data lake. Based on this data lake, digital shadows aggregate data for a specific purpose. For example, digital shadows in production planning and control help to manage the dynamic changes like delays in production or machine break–downs. This paper examines the existing research in the field of digital twins and digital shadows in manufacturing and gives a brief overview of the historical development. In particular, the potential and possible applications of digital shadows in production planning and control are analyzed. A top–down–bottom–up approach is developed to support the design of digital shadows in production planning and control