Comparison of preoperative short-course radiotherapy and long-course radiochemotherapy for locally advanced rectal cancer.

BACKGROUND: The purpose of this work was to perform a single institution comparison between preoperative short-course radiotherapy (SC-RT) and long-course radiochemotherapy (LC-RCHT) for locally advanced rectal cancer. METHODS: A total of 225 patients with clinical stage UICC II-III rectal cancer were treated with SC-RT (29 Gy in 10 twice daily fractions followed by immediate surgery; n = 108) or LC-RCHT (54 Gy in 28 fractions with simultaneous 5-fluorouracil (5-FU) ± oxaliplatin chemotherapy followed by delayed surgery; n = 117). All patients in the LC-RCHT cohort and patients in the SC-RT with pathological UICC stage ≥ II received adjuvant chemotherapy. Before 2004, the standard of care was SC-RT with LC-RCHT reserved for patients where downstaging was considered as required for sphincter preservation or curative resection. In the later period, SC-RT was practiced only for patients unfit for radiochemotherapy. RESULTS: Patients in the LC-RCHT cohort had a significantly higher proportion of cT4 tumors, clinical node positivity, and lower tumor location. The 5-year local control (LC) and overall survival (OS) were 91% and 66% without differences between the SC-RT and LC-RCHT groups. Acute toxicity was increased during LC-RCHT (grade ≥ II 1% vs. 33%) and there were no differences in postoperative complications. Severe late toxicity grade ≥ III was increased after SC-RT (12% vs. 3%). Of patients aged > 80 years, 7 of 7 patients and 4 of 9 patients received curative surgery after SC-RT and LC-RCHT, respectively. CONCLUSION: Despite the fact that patients with worse prognostic factors were treated with LC-RCHT, there were no significant differences in LC and OS between the SC-RT and LC-RCHT group. Age > 80 years was identified as a significant risk factor for LC-RCHT and these patients could be treated preferably with SC-RT.

A novel vacuum device for extremity immobilisation during digital angiography: preliminary clinical experiences.

Our objective was to develop and evaluate a non-invasive device for rigid immobilisation during extremity angiography. The patented BodyFix immobilisation device (Medical Intelligence, Schwabmünchen, Germany) consists of a vacuum pump connected to special cushions and a plastic foil that covers the body part to be immobilised. First, the patient's extremity is covered by a thin plastic bag and then wrapped in one of the cushions, placed on the top of the therapy couch, and covered with the plastic foil. The air is evacuated from the cushion under the covering foil by the vacuum pump, resulting a hardening of the cushion and thus immobilisation of the patient's extremity. The rigid immobilisation resulted in a complete absence of motion artefacts in the majority of patients. No pixeling of the images was required in any of the 100 patients vs 32% in the control group. Repetition of series could be avoided in all cases and a substantial increase in the quality of the images was obtained. Setup of the device takes an additional 1-2 min. Vacuum immobilisation allows for comfortable, effective immobilisation during digital subtraction angiography, eliminating motion artefacts. This device has become an indispensable tool in daily clinical routine at our department.

Virtual endoscopy for planning neuro-endoscopic intraventricular surgery.

To evaluate the usefulness of virtual endoscopy (VE) in planning neuroendoscopic intraventricular surgeries, the technique was applied in 20 of 22 consecutive procedures. Thirteen endoscopic third ventriculostomies (ETV) in 12 patients, 3 endoscopic colloid cyst removals, 1 third ventricular arachnoidal cyst fenestration, 1 endoscopic ventricul-cysto-cisternostomy (suprasellar arachnoidal cyst), 1 endoscopic tumor biopsy, one third ventricular gross total tumor removal and 2 septostomies at the foramen of Monro due the septal occlusion were performed. Contrast medium-enhanced MR images (3DMPRAGE, Siemens, Germany) were semi-automatically segmented with a surface-rendering technique ("Navigator" software, General Electric Medical, Buc, France) to produce the virtual endoluminal views. Surgery was performed with cerebral ventriculoscopes by Wolf (Richard Wolf, Knittlingen, Germany). VE was feasible in all patients and the virtual endoscopic images were comparable with the real intraventricular views obtained by standard rod lens systems. After contrast medium administration intra- and paraventricular vessels such as the thalamocaudate vein, the septal veins, the basilar artery and its branches (distal BA complex) and the choroid plexus were identified on the virtual endoscopic images. In 8 patients, the additional anatomic information provided by VE profoundly influenced surgical planning. VE provides the neurosurgeon with additional morphological information supporting the planning process of neuroendoscopic intraventricular surgeries, contributing to the safety of the procedures.

A simple and non-invasive vacuum mouthpiece-based head fixation system for high precision radiotherapy.

PURPOSE: To demonstrate why conventional non-invasive mouthpiece-based fixation has not achieved the expected accuracy and to suggest a solution of the problem. PATIENTS AND METHODS: The Vogele Bale Hohner (VBH) head holder is a non-invasive vacuum mouthpiece-based head fixation system. Feasibility and repositioning accuracy were evaluated by portal image analysis in 12 patients with cranial tumors intended for stereotactic procedures, fixated with the newest version (VBH HeadFix-ARC). RESULTS: Portal image analysis (8 patients evaluated in 2-D, 4 patients in 3-D) showed that even in routine external beam radiation therapy, treatment can be applied to within a mean 2-D and 3-D accuracy of under 2 mm (SD 0.92 mm and 1.2 mm, respectively) with cost and repositioning time per patient and patient comfort comparable to that of common thermoplastic masks. CONCLUSION: These preliminary results show that high repositioning accuracy does not rule out simple and quick application and patient comfort. Paramount, however, is tensionless repositioning via the vacuum mouthpiece.

Computer-assisted neurosurgery by using a noninvasive vacuum-affixed dental cast that acts as a reference base: another step toward a unified approach in the treatment of brain tumors.

OBJECT: The purpose of the study was to evaluate the use of the Vogele-Bale-Hohner (VBH) mouthpiece, which is attached to the patient's upper jaw by negative pressure, for patient-image registration and for tracking the patient's head during image-guided neurosurgery. METHODS: A dynamic reference frame (DRF) is reproducibly mounted on the mouthpiece. Reference points, optimally distributed and attached to the mouthpiece, are used for registration in the patient's absence on the day before surgery. In the operating room, the mouthpiece and DRF are precisely repositioned using a vacuum, and the patient's anatomical structures are automatically registered to corresponding ones on the image. Experimental studies and clinical experiences in 10 patients confirmed repeated (rigid body) localization accuracy in the range of 0 to 2 mm, throughout the entire surgery despite movements by the patient. CONCLUSIONS: Because of its noninvasive, rigid, reliable, and reproducible connection to the patient's head, the VBH vacuum-affixed mouthpiece grants the registration device an accuracy comparable to invasive fiducial markers.

Generic combustion method for determination of crude protein in feeds: collaborative study.

Nine laboratories participated in a collaborative study on determination of crude protein in animal feeds to compare a generically described combustion method with the AOAC mercury catalyst Kjeldahl method (7.015). The combustion method was written in general terms of method principle, apparatus specifications, and performance requirements. The sample set comprised closely matched pairs of feed ingredients and mixed products ranging from 10 to 90% protein. Ten pairs ground to 0.5 mm were the focus of the study; 4 pairs were ground to 1.0 mm for comparison. Nicotinic acid and lysine monohydrochloride were included as standards. Collaborators were instructed to report their results for performance checks using materials supplied. Only one laboratory failed to meet the proposed limits. Seven laboratories used the LECO Model FP-228 analyzer and 2 used the LECO CHN 600 analyzer. For the 0.5 mm pairs, repeatability standard deviations (Sr) ranged from 0.09 to 0.58 for the Kjeldahl method and from 0.14 to 0.33 for the combustion method, with a pooled Sr value of 0.28 and relative standard deviation (RSDr) of 0.59%. Reproducibility standard deviations (Sg) ranged from 0.23 to 0.86 (Kjeldahl) and from 0.30 to 0.61 (combustion), with a pooled Sg value of 0.52 and RSDg of 1.10%. Grand means for the samples ground to 0.5 mm were 47.65% protein by the combustion method and 47.41% protein by the Kjeldahl method. For samples ground to 1.0 mm, corresponding values were 31.82 and 31.50% protein. The generic combustion method has been approved interim official first action.

Comparison of LECO FP-228 "nitrogen determinator" with AOAC copper catalyst Kjeldahl method for crude protein.

The LECO FP-228 "Nitrogen Determinator" was compared with the AOAC copper catalyst Kjeldahl method, 7.033-7.037, for the determination of crude protein in feed materials. The completely microprocessor-controlled instrument determines nitrogen by measuring the nitrogen gas following combustion of the sample; it was easy to operate and broadly applicable. A wide variety of feed materials of various nitrogen levels were analyzed in one mixed sequence. Results were precise, accurate, and rapid. Analysis time for one sample was approximately 3 min. Fourteen samples containing 2.5-15.5% N were selected for study and consisted of meals, grains, forages, and standard organic materials. The overall mean for the 14 samples by the LECO combustion method was 8.61% N compared with an overall mean of 8.58% N for the AOAC Kjeldahl method. Within-sample standard deviations for the LECO combustion method ranged from 0.013 to 0.052% N with a pooled standard deviation (SD) of 0.033% N for the 14 samples. Standard deviations for the AOAC Kjeldahl method ranged from 0.006 to 0.035% N with a pooled SD of 0.022% N. Combined average recovery of nitrogen from tryptophan, lysine-HCl, and EDTA determined by the LECO combustion method was 99.94% compared to 99.88% determined by the AOAC Kjeldahl method.

Radiotherapy of bronchogenic carcinoma. Analysis of a treatment schedule designed for use with hyperbaric oxygen.

All cases of bronchogenic carcinoma treated with curative intent over an eight-year period were reviewed. Most were treated with 12 X 400 rad in 32 days using 60Co, a schedule designed to optimize the radiation-sensitizing properties of hyperbaric oxygen. While O2 gave no obvious benefit, overall four-year survival was 10.6% and that of patients with good prognostic indicators was 18%. No radiation myelitis was observed. This protocol delivers an adequate tumor dose and appears to be tolerated well by most patients.