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Katja Oberholzer,
Matthias Menig,
Andreas Pohlmann,
Theodor Junginger,
Achim Heintz,
Andreas Kreft,
Torsten Hansen, Astrid Schneider,
André Lollert,
Heinz Schmidberger,
Düber Christoph
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ABSTRACT: PURPOSE: To assess pretreatment functional and morphological tumor characteristics with magnetic resonance imaging (MRI) in advanced rectal carcinoma and to identify factors predicting response to neoadjuvant chemoradiation. MATERIALS AND METHODS: In a prospective study, 95 patients with rectal carcinoma underwent dynamic contrast-enhanced MRI before and after chemoradiation. Quantitative parameters were derived from a pharmacokinetic two-compartment model. Tumors were also characterized with regard to mucinous status at pretreatment high-resolution MRI as nonmucinous or mucinous. Response to treatment was defined as a downshift in the local tumor stage. RESULTS: The parameter k(21) (contrast medium exchange rate) was higher at pretreatment MRI in nonmucinous compared with mucinous carcinomas (P < 0.001). The effect of chemoradiation on dynamic MR parameters was higher in nonmucinous carcinomas than in the mucinous subtype (P < 0.001). A higher rate of response to treatment was linked with nonmucinous morphology (P < 0.001). Multivariate analysis revealed an association between mucinous tumor morphology and poor response (odds ratio [95% confidence interval]: 0.113 [0.032-0.395], P < 0.001) as well as an association between a high 75th percentile of k(21) and a higher response rate (odds ratio: 1.043 [1.001-1.086], P = 0.019). CONCLUSION: Functional and morphological parameters of pretreatment MRI can assess tumor characteristics associated with the effectiveness of chemoradiation before treatment initiation. J. Magn. Reson. Imaging 2012;. © 2012 Wiley Periodicals, Inc.
Journal of Magnetic Resonance Imaging 11/2012; · 2.70 Impact Factor
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Katja Oberholzer,
Matthias Menig,
Andreas Kreft, Astrid Schneider,
Theodor Junginger,
Achim Heintz,
Karl-Friedrich Kreitner,
Andreas M Hötker,
Torsten Hansen,
Christoph Düber,
Heinz Schmidberger
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ABSTRACT: To assess response of locally advanced rectal carcinoma to chemoradiation with regard to mucinous status and local tumor invasion found at pretherapeutic magnetic resonance imaging (MRI).
A total of 88 patients were included in this prospective study of patients with advanced mrT3 and mrT4 carcinomas. Carcinomas were categorized by MRI as mucinous (mucin proportion >50% within the tumor volume), and as nonmucinous. Patients received neoadjuvant chemoradiation consisting of 50.4 Gy (1.8 Gy/fraction) and 5-fluorouracil on Days 1 to 5 and Days 29 to 33. Therapy response was assessed by comparing pretherapeutic MRI with histopathology of surgical specimens (minimum distance between outer tumor edge and circumferential resection margin = CRM, T, and N category).
A mucinous carcinoma was found in 21 of 88 patients. Pretherapeutic mrCRM was 0 mm (median) in the mucinous and nonmucinous group. Of the 88 patients, 83 underwent surgery with tumor resection. The ypCRM (mm) at histopathology was significantly lower in mucinous carcinomas than in nonmucinous carcinomas (p ≤ 0.001). Positive resection margins (ypCRM ≤ 1 mm) were found more frequently in mucinous carcinomas than in nonmucinous ones (p ≤ 0.001). Treatment had less effect on local tumor stage in mucinous carcinomas than in nonmucinous carcinomas (for T downsizing, p = 0.012; for N downstaging, p = 0.007). Disease progression was observed only in patients with mucinous carcinomas (n = 5).
Mucinous status at pretherapeutic MRI was associated with a noticeably worse response to chemoradiation and should be assessed by MRI in addition to local tumor staging to estimate response to treatment before it is initiated.
International journal of radiation oncology, biology, physics 01/2011; 82(2):842-8. · 4.59 Impact Factor
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ABSTRACT: Our aim was to longitudinally analyze the vocal outcome after endoscopic CO(2) laser resection of early glottic carcinoma.
Sixteen patients treated with laser surgery for T1 or T2 tumors of the vocal cords received voice therapy and were examined 1, 2, 3, 4.5, 6 and 12 months postoperatively. Besides videolaryngostroboscopy, each examination included history, phonetogram of the speaking and the singing voice, language-specific hoarseness diagram and a questionnaire (Voice Handicap Index 12 in German).
Objective parameters demonstrated a broad variability with a slight tendency of improvement over time. For the maximal phonation time a nearly constant improvement was seen. After an initial improvement deterioration for subjective assessment in the Voice Handicap Index was noted in most patients 3-6 months postoperatively.
The functional outcome after cordectomy is variable. MESSAGE OF THE PAPER: Discrepancies between objective findings and patient satisfaction over time have to be considered after cordectomy.
ORL 01/2011; 73(1):38-46. · 0.91 Impact Factor
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ABSTRACT: Regression analysis is an important statistical method for the analysis of medical data. It enables the identification and characterization of relationships among multiple factors. It also enables the identification of prognostically relevant risk factors and the calculation of risk scores for individual prognostication.
This article is based on selected textbooks of statistics, a selective review of the literature, and our own experience.
After a brief introduction of the uni- and multivariable regression models, illustrative examples are given to explain what the important considerations are before a regression analysis is performed, and how the results should be interpreted. The reader should then be able to judge whether the method has been used correctly and interpret the results appropriately.
The performance and interpretation of linear regression analysis are subject to a variety of pitfalls, which are discussed here in detail. The reader is made aware of common errors of interpretation through practical examples. Both the opportunities for applying linear regression analysis and its limitations are presented.
11/2010; 107(44):776-82. · 2.92 Impact Factor
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ABSTRACT: The purpose of this study was to assess the incidence and risk factors of postoperative nausea and vomiting (PONV) after craniotomy because most available data about PONV in neurosurgical patients are retrospective in nature or derive from small prospective studies.
Postoperative nausea and vomiting was prospectively assessed within 24 hours after surgery in 229 patients requiring supratentorial or infratentorial craniotomy. To rule out the relevance of the neurosurgical procedure itself to the development of PONV, the observed incidence of vomiting was compared with the rate of vomiting predicted with a surgery-independent risk score (Apfel postoperative vomiting score).
The overall incidence of PONV after craniotomy was 47%. Logistic regression identified female sex as a risk factor for postoperative nausea (OR 4.25, 95% CI 2.3-7.8) and vomiting (OR 2.62, 95% CI 1.4-4.9). Both the incidence of nausea (OR 3.76, 95% CI 2.06-6.88) and vomiting (OR 4.48, 95% CI 2.4-8.37) were increased in patients not receiving steroids. Postoperative nausea and vomiting occurred after infratentorial as well as after supratentorial procedures. The observed incidence of vomiting within 24 hours after surgery was higher (49%) than would be predicted with the Apfel surgery-independent risk score (31%; p = 0.0004).
The overall incidence of PONV within 24 hours after craniotomy was approximately 50%. One possible reason is that intracranial surgeries pose an additional and independent risk factor for vomiting, especially in female patients. Patients undergoing craniotomy should be identified as high-risk patients for PONV.
Journal of Neurosurgery 10/2010; 114(2):491-6. · 2.96 Impact Factor
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Peter P Urban,
Thomas Wolf,
Michael Uebele,
Jürgen J Marx,
Thomas Vogt,
Peter Stoeter,
Thomas Bauermann,
Carsten Weibrich,
Goran D Vucurevic, Astrid Schneider,
Jörg Wissel
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ABSTRACT: There is currently no consensus on (1) the percentage of patients who develop spasticity after ischemic stroke, (2) the relation between spasticity and initial clinical findings after acute stroke, and (3) the impact of spasticity on activities of daily living and health-related quality of life.
In a prospective cohort study, 301 consecutive patients with clinical signs of central paresis due to a first-ever ischemic stroke were examined in the acute stage and 6 months later. At both times, the degree and pattern of paresis and muscle tone, the Barthel Index, and the EQ-5D score, a standardized instrument of health-related quality of life, were evaluated. Spasticity was assessed on the Modified Ashworth Scale and defined as Modified Ashworth Scale >1 in any of the examined joints.
Two hundred eleven patients (70.1%) were reassessed after 6 months. Of these, 42.6% (n=90) had developed spasticity. A more severe degree of spasticity (Modified Ashworth Scale >or=3) was observed in 15.6% of all patients. The prevalence of spasticity did not differ between upper and lower limbs, but in the upper limb muscles, higher degrees of spasticity (Modified Ashworth Scale >or=3) were more frequently (18.9%) observed than in the lower limbs (5.5%). Regression analysis used to test the differences between upper and lower limbs showed that patients with more severe paresis in the proximal and distal limb muscles had a higher risk for developing spasticity (P<or=0.001). Spasticity of the upper and lower limb was more frequent in patients with hemihypesthesia than in patients without sensory deficits (P<or=0.001). Patients with spasticity showed a lower Barthel Index and EQ-5D score compared with the group without spasticity.
Spasticity was present in 42.6% of patients with initial central paresis. However, severe spasticity was relatively rare. Predictors for the development of spasticity were a severe degree of paresis and hemihypesthesia at stroke onset.
Stroke 09/2010; 41(9):2016-20. · 5.73 Impact Factor
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ABSTRACT: Pain after craniotomy may be underdiagnosed, despite the fact that it can increase postoperative complications for example arterial hypertension and postoperative hemorrhage. This study investigates the incidence and intensity of pain after craniotomy and characterizes the influencing parameters. During a 1-year period 256 patients undergoing elective craniotomy were prospectively included in the study. Intensity of pain was evaluated 1, 4, and 24 hours after extubation using a verbal numerical rating scale (NRS) ranging from 0 (no pain) to 10 (maximal pain). Routine perioperative pain management was not influenced by the investigators. Parameters including patient-related factors, drug administration, and surgical factors were correlated with incidence and intensity of postcraniotomy pain. Statistical analysis: logistic regression and chi using SPSS program (Windows, version 12.0). During the first 24 hours 87% of the patients experienced pain (NRS 1 to 3: 32%, NRS 4 to 7: 44%, NRS 8 to 10: 11%). For postoperative analgesia, the opioid piritramide (a mu-receptor agonist) was administered to 70% and nonopiod analgesics to 73% of the patients. The probability of experiencing postcraniotomy pain was reduced by 3% for each year of life. Maintenance of anesthesia with sevoflurane increased the probability of suffering from postcraniotomy pain by 147% and the absence of corticosteroids by 119%. Other investigated parameters did not influence pain after craniotomy. This study shows that pain is experienced by the majority of patients after craniotomy, despite conventional pain management, emphasizing the necessity for improved and individualized pain management in this special group of patients.
Journal of neurosurgical anesthesiology 07/2010; 22(3):202-6. · 2.41 Impact Factor
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ABSTRACT: Chest pain units (CPUs) have been established to optimize treatment of patients with acute coronary syndrome (ACS) and to early and accurately discharge patients with non-coronary chest pain. The aim of this analysis was to elucidate whether treatment of ACS patients in the CPU versus emergency department (ED) has prognostic implications.
Patients presenting with suspected ACS to either the ED between August 2004 and June 2005 or the CPU between July 2005 and May 2006 were retrospectively analyzed. Of 1,796 included patients, 483 had the discharge diagnosis ACS. When compared to patients with exclusion of ACS they had more cardiovascular risk factors and higher troponin, creatinine and C-reactive protein levels (P < 0.001) at admission. Within 1 year, 37 patients of the ACS group suffered an event. Treatment in the ED compared with the CPU showed a significant increase in hazard ratio of 2.1 (P = 0.034) for the combined endpoint death, myocardial infarction and stroke, remaining unchanged after adjusting for confounders. Event-free 1-year survival was higher in CPU patients for the combined endpoint (P (logrank) = 0.02).
These results demonstrate a better 1-year prognosis for ACS patients treated in the CPU instead of the ED, therefore, supporting the idea to establish CPUs in Europe.
Clinical Research in Cardiology 03/2010; 99(3):149-55. · 2.95 Impact Factor
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ABSTRACT: Postischemic endogenous neurogenesis can be dose-dependently modulated by volatile anesthetics. The intravenous anesthetic propofol is used during operations with a risk of cerebral ischemia, such as neurosurgery, cardiac surgery, and vascular surgery. The effects of propofol on neurogenesis are unknown and, therefore, the object of this study.
Eighty male Sprague-Dawley rats were randomly assigned to treatment groups with propofol administration for 3 h: 36 mg x kg(-1) x h(-1) propofol with or without cerebral ischemia and 72 mg x kg(-1) x h(-1) propofol with or without cerebral ischemia. In addition, 7 rats with propofol administration for 6 h and 14 treatment-naive rats were investigated. Forebrain ischemia was induced by bilateral carotid artery occlusion and hemorrhagic hypotension. Animals received 5-bromo-2-deoxyuridine for 7 days. 5-Bromo-2-deoxyuridine-positive neurons were counted in the dentate gyrus after 9 and 28 days. Spatial learning in the Barnes maze and histopathologic damage of the hippocampus were analyzed.
Propofol revealed no impact on basal neurogenesis. Cerebral ischemia increased the amount of new neurons. After 28 days, neurogenesis significantly increased in animals with low-dose propofol administered during cerebral ischemia compared with naive animals, whereas no significant difference was observed in animals with high-dose propofol during ischemia. Neuronal damage in the CA3 region was increased at 28 days with high-dose propofol. Postischemic deficits in spatial learning were not affected by propofol.
Independent effects of propofol are difficult to ascertain. Peri-ischemic propofol administration may exert secondary effects on neurogenesis by modulating the severity of histopathologic injury and thereby regenerative capacity of the hippocampus.
Anesthesiology 03/2009; 110(3):529-37. · 5.36 Impact Factor
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ABSTRACT: Background: Postischemic endogenous neurogenesis can be dose-dependently modulated by volatile anesthetics. The intravenous anesthetic propofol is used during operations with a risk of cerebral ischemia, such as neurosurgery, cardiac surgery, and vascular surgery. The effects of propofol on neurogenesis are unknown and, therefore, the object of this study.
Anesthesiology 02/2009; 110(3):529-537. · 5.36 Impact Factor
