Pavel Ryska

Prognostic impact of hemoglobin level prior to radiotherapy on survival in patients with glioblastoma.

Purpose:To evaluate prognostic factors in patients with glioblastoma treated with postoperative or primary radiotherapy.Patients and Methods:From 1989 to 2000, a total of 100 patients underwent irradiation as part of their initial treatment for glioblastoma. All patients had undergone surgery or biopsy followed by conventional external-beam radiotherapy. 85 patients who received the planned dose of irradiation (60 Gy in 30 fractions) were analyzed for the influence of prognostic factors. 73/85 (86%) of patients were given postoperative irradiation, while 12/85 (14%) of patients were primarily treated with radiotherapy after biopsy.Results:The median overall survival was 10.1 months (range, 3.7–49.8 months), the 1- and 2-year survival rates were 41% and 5%, respectively. Univariate analysis revealed age ≤ 55 years (p < 0.001), pre-radiotherapy hemoglobin (Hb) level > 12 g/dl (p = 0.009), and pre-radiotherapy dose of dexamethasone ≤ 2 mg/day (p = 0.005) to be associated with prolonged survival. At multivariate analysis, younger age (p < 0.001), higher Hb level (p = 0.002), lower dose of dexamethasone (p = 0.026), and a hemispheric tumor location (p = 0.019) were identified as independent prognostic factors for longer survival. The median survival for patients with an Hb level > 12 g/dl was 12.1 months compared to 7.9 months for those with a lower Hb level. Contingency-table statistics showed no significant differences for the two Hb groups in the distribution of other prognostic factors.Conclusion:The results indicate that lower Hb level prior to radiotherapy for glioblastoma can adversely influence prognosis. This finding deserves further evaluation.Ziel:Evaluation prognostischer Faktoren bei Patienten mit Glioblastom, die mit postoperativer oder primärer Strahlentherapie behandelt wurden.Patienten und Methodik:Bei 100 Patienten mit Glioblastom wurde in den Jahren 1989–2000 die Strahlentherapie im Rahmen der Primärbehandlung angewandt. Bei allen Patienten wurde eine Operation oder Biopsie mit nachfolgender konventioneller perkutaner Bestrahlung durchgeführt. Der Einfluss der prognostischen Faktoren wurde bei 85 Patienten, die die geplante Strahlendosis (60 Gy in 30 Fraktionen) erhielten, evaluiert. 73/85 Patienten (86%) wurden mit postoperativer Bestrahlung, 12/85 Patienten (14%) mit primärer Strahlentherapie und Biopsie behandelt.Ergebnisse:Die mittlere Überlebenszeit betrug 10,1 (3,7–49,8) Monate, die Überlebenszeit nach 1 und 2 Jahren lag bei 41% bzw. 5%. Mittels der univariaten Analyse stellten sich folgende Faktoren dar, die mit einer längeren Überlebenszeit verbunden sind: ein Alter ≤ 55 Jahre (p < 0,001), eine Hämoglobin-(Hb-)Konzentration zu Beginn der Strahlentherapie > 12 g/dl (p = 0,009) und eine prätherapeutische Dexamethasondosis ≤ 2 mg/Tag (p = 0,005). Die multivariate Analyse ermittelte ein jüngeres Alter (p < 0,001), eine höhere Hb-Konzentration (p = 0,002), eine niedrigere Dexamethasondosis (p = 0,026) und eine hemisphärische Tumorlokalisation (p = 0.019) als unabhängige prognostische Faktoren für eine längere Überlebenszeit. Die mittlere Überlebenszeit bei Patienten mit einer Hb-Konzentration > 12 g/dl betrug 12,1 Monate, bei Patienten mit einem niedrigeren Blut-Hb-Wert dagegen nur 7,9 Monate. Die Kontingenztabellenstatistik zeigte keine signifikanten Unterschiede in der Distribution der anderen prognostischen Faktoren bei beiden Hb-Gruppen.Schlussfolgerung:Die Ergebnisse weisen darauf hin, dass eine niedrigere Hb-Konzentration vor Beginn der Strahlentherapie wegen Glioblastoms einen negativen Einfluss auf die Prognose haben kann. Diese Beobachtung verdient weitere Aufmerksamkeit.

COMPARISON OF DUPLEX ULTRASONOGRAPHY AND MAGNETIC RESONANCE IMAGING IN THE DETECTION OF SIGNIFICANT RENAL ARTERY STENOSIS

OBJECTIVE The aim of our study was to evaluate duplex ultrasonography (DUS) and magnetic resonance angiography (MRA) in detection of haemodynamically significant renal artery stenosis (RAS). METHODS The study included patients with high clinical suspicion of renovascular hypertension (RVH). The imaging of renal arteries was performed by DUS, MRA and digital subtraction angiography (DSA). Significant RAS was defined as maximum systolic velocity > or =180 cm/sec (DUS) or as 60% reduction of the endoluminal arterial diameter (MRA, DSA). The results of DUS and MRA were assessed in respect to the results of DSA. RESULTS Arterial supply of 186 kidneys in 94 patients was evaluated. DSA revealed significant RAS in 61 kidneys evaluated. DUS was not able to examine arterial supply in 18 kidneys of 13 patients. In the detection of significant RAS, DUS was characterized by sensitivity and specificity of 85% and 84%. MRA achieved satisfactory imaging quality in all but one kidney evaluated. The sensitivity and specificity of MRA in the detection of significant RAS was 93% and 93%, respectively. CONCLUSION In patients with high clinical probability of RVH, MRA proved to be more reliable and superior in both sensitivity and specificity to DUS in the detection of significant RAS.

MRI-based Preplanning Using CT and MRI Data Fusion in Patients With Cervical Cancer Treated With 3D-based Brachytherapy: Feasibility and Accuracy Study

PURPOSE Magnetic resonance imaging (MRI)-assisted radiation treatment planning enables enhanced target contouring. The purpose of this study is to analyze the feasibility and accuracy of computed tomography (CT) and MRI data fusion for MRI-based treatment planning in an institution where an MRI scanner is not available in the radiotherapy department. METHODS AND MATERIALS The registration inaccuracy of applicators and soft tissue was assessed in 42 applications with CT/MRI data fusion. The absolute positional difference of the center of the applicators was measured in four different planes from the top of the tandem to the cervix. Any inaccuracy of registration of soft tissue in relation to the position of applicators was determined and dose-volume parameters for MRI preplans and for CT/MRI fusion plans with or without target and organs at risk (OAR) adaptation were evaluated. RESULTS We performed 6,132 measurements in 42 CT/MRI image fusions. Median absolute difference of the center of tandem on CT and MRI was 1.1 mm. Median distance between the center of the right ovoid on CT and MRI was 1.7 and 1.9 mm in the laterolateral and anteroposterior direction, respectively. Corresponding values for the left ovoid were 1.6 and 1.8 mm. Rotation of applicators was 3.1°. Median absolute difference in position of applicators in relation to soft tissue was 1.93, 1.50, 1.05, and 0.84 mm in the respective transverse planes, and 1.17, 1.28, 1.27, and 1.17 mm in selected angular directions. The dosimetric parameters for organs at risk on CT/MRI fusion plans without OAR adaptation were significantly impaired whereas the target coverage was not influenced. Planning without target adaptation led to overdosing of the target volume, especially high-risk clinical target volume--D₉₀ 88.2 vs. 83.1 (p < 0.05). CONCLUSIONS MRI-based preplanning with consecutive CT/MRI data fusion can be safe and feasible, with an acceptable inaccuracy of soft tissue registration.

Iterative reconstruction of pulmonary MDCT angiography: Effects on image quality, effective dose and estimated organ dose to the breast

AIMS To compare the image characteristics, effective dose and estimated organ dose to the female breast in pulmonary MDCT angiography (MDCTA), reconstructed with either standard filtered back projection (FBP), or iterative reconstruction in image space (IRIS). METHODS Pulmonary MDCTA performed in 116 females (age 18 - 77 years; body mass index 15 - 48) was reconstructed with FBP (n=52) or IRIS (n=64). Scans were acquired on a 128-row MDCT system using automatic tube current modulation, 100 kV tube voltage, and a quality reference mAs value of 120 (FBP) and 80 (IRIS). Dose was calculated from CT dose index (CTDIvol) and dose length product (DLP) values utilising ImPACT software. Image noise was measured within the pulmonary artery. Qualitative visual assessment of the scans was performed (1=negligible noise, 5=noise obscuring diagnostic information). RESULTS The average CTDIvol yielded 4.33 mGy for FBP and 3.54 mGy for IRIS, respectively (18.2% decrease). The average effective scan dose was 2.73±0.57 mSv (FBP) and 2.29±0.68 mSv (IRIS), respectively (16.1% decrease). The estimated average organ dose to the breast decreased from 5.1±1.1 mGy (FBP) to 4.2±1.2 mGy (IRIS, 17.6% decrease). No non-diagnostic scans (score 5) were encountered in either group. Significant improvement in image noise levels (P<0.01) and subjective image quality (P<0.02) were noted in IRIS group. CONCLUSION Pulmonary MDCTA utilizing a 100 kV technique, automatic tube current modulation, and iterative image reconstruction offers robust results in routine conditions among an unselected female population, with breast doses being comparable to two-view digital mammography. Moreover, iterative reconstruction offers improvements in both image noise and visual perception of the scans, thus suggesting a potential for further dose reduction.

Integration of Endovascular Therapy of Ruptured Abdominal and Iliac Aneurysms in the Treatment Algorithm: A Single-Center Experience in a Medium-Volume Vascular Center

Purpose: To evaluate the influence of endovascular therapy of ruptured abdominal or iliac aneurysms on total mortality. Materials and Methods: We analyzed the mortality of 40 patients from 2005 to 2009, when only surgical treatment was available. These results were compared with the period 2010 to 2013, when endovascular aneurysm repair (EVAR) was assessed as the first option in selected patients. Results: During 2005 to 2009, the mortality was 37.5%. From 2010 to 2013, 45 patients were treated with mortality 28.9%. Open repair was performed in 35 (77.8%) patients and EVAR in 10 (22.2%) patients. The 30-day and 1-year mortality rates of the EVAR group were 0% and 20%, respectively, and the total mortality rate was 30% during follow-up (median 11 months, range 1-42 months). The 30-day mortality in the surgical group remained unchanged, at 37.1%, and 1-year and total mortality rates were 45.7% and 51.4%, respectively. Conclusion: Following integration in the treatment algorithm, EVAR decreased total mortality in our center by 8.6%.

Reduction of effective dose and organ dose to the eye lens in head MDCT using iterative image reconstruction and automatic tube current modulation.

AIMS To compare the effective and eye lens radiation dose in helical MDCT brain examinations using automatic tube current modulation in conjunction with either standard filtered back projection (FBP) technique or iterative reconstruction in image space (IRIS). METHODS Of 400 adult brain MDCT examinations, 200 were performed using FBP and 200 using IRIS with the following parameters: tube voltage 120 kV, rotation period 1 second, pitch factor 0.55, automatic tube current modulation in both transverse and longitudinal planes with reference mAs 300 (FBP) and 200 (IRIS). Doses were calculated from CT dose index and dose length product values utilising ImPACT software; the organ dose to the lens was derived from the actual tube current-time product value applied to the lens. Image quality was assessed by two independent readers blinded to the type of image reconstruction technique. RESULTS The average effective scan dose was 1.47±0.26 mSv (FBP) and 0.98±0.15 mSv (IRIS), respectively (33.3% decrease). The average organ dose to the eye lens decreased from 40.0±3.3 mGy (FBP) to 26.6±2.0 mGy (IRIS, 33.5% decrease). No significant change in diagnostic image quality was noted between IRIS and FBP scans (P=0.17). CONCLUSION Iterative reconstruction of cerebral MDCT examinations enables reduction of both effective and organ eye lens dose by one third without signficant loss of image quality.

Long-term experience with endovascular therapy of the descending thoracic aorta

BackgroundTo review single centre experience of endovascular treatment of descending thoracic aorta.MethodsBetween May 1999 and September 2012, 72 patients were treated overall (53 men, 19 women, mean age 60.1 years) for degenerative aneurysms (n = 5), ruptured aneurysms (n = 4), aortic ulcers (n = 8), infected aneurysms (n = 4), type B aortic dissections (n = 23), and traumatic aortic injuries (n = 28).ResultsThe technical success rate was 98.6%, 30-day mortality was 8.3%, 1-year mortality was 13.8%, and overall mortality was 22.2%. Mortality caused by the treatment of aortic diseases was 6.9%. Permanent stroke occurred in 1 patient, and paraplegia developed in 1 patient. In a group of 23 patients whose left subclavian artery (LSA) was covered, claudication of the left upper extremity developed in 2 cases.ConclusionsEndovascular therapy offers a very effective and less invasive alternative to the surgical approach for a wide range of the thoracic aortic disease. The main advantage of using TEVAR seems to be in acute conditions when a stent graft stabilizes the aorta and prevents further bleeding and organ ischemia. Regular follow-up is mandatory for early recognition of specific TEVAR complications.

Computed tomography pulmonary embolism residua index (CTPER-index): a simple tool for pulmonary embolism residua description

Objective: Chronic thromboembolic pulmonary hypertension (CTEPH) is a relatively common long-term complication of acute pulmonary embolism (PE) with severely negative impact on the patient’s quality of life and prognosis. The aim of our study was to assess morphological changes, with respect to CTEPH development, in the pulmonary artery vascular bed 6 months after diagnosis of acute PE as the first thromboembolic event in the patient`s history. Methods: Our prospective study included a population of 87 consecutive patients with proven PE. Multidetector computer tomography pulmonary arteriography (CTA) was performed 6 months after acute PE to assess residua of thrombi and abnormalities supporting the presence of pulmonary hypertension. To quantify the individual totality of morphological abnormalities, a computer tomography pulmonary embolism residua index (CTPER-index) was constructed and groups of patients with and without CTEPH were compared. The study follow-up was 24 months, with echocardiography performed 6, 12, and 24 months after PE. Results: Morphological abnormalities corresponding to thrombi residua or pulmonary hypertension on CTA were found in 68% of patients. The CTPER-index reached significantly higher values in patients with CTEPH during a 2-year follow-up. A CTPER-index value ≥4 equates to a 12-fold higher risk of CTEPH development (p=0.013) with sensitivity 0.80 (95% CI 0.31; 0.989) and specificity 0.79 (95% CI 0.754; 0.799). Conclusion: Our CTPER-index may provide useful information for a clinician performing CTA for differential diagnosis of dyspnea in a patient with a history of PE.