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Featured researches published by Vlastimil Válek.


CardioVascular and Interventional Radiology | 2011

Covered Biodegradable Stent: New Therapeutic Option for the Management of Esophageal Perforation or Anastomotic Leak

Marie Cerna; Martin Köcher; Vlastimil Válek; René Aujeský; Čestmír Neoral; Tomáš Andrašina; Jiří Pánek; Shankari Mahathmakanthi

PurposeThis study was designed to evaluate our experience with the treatment of postoperative anastomotic leaks and benign esophageal perforations with covered biodegradable stents.Materials and MethodsFrom 2008 to 2010, we treated five men with either an anastomotic leak or benign esophageal perforation by implanting of covered biodegradable Ella-BD stents. The average age of the patients was 60 (range, 38–74) years. Postoperative anastomotic leaks were treated in four patients (1 after esophagectomy, 1 after resection of diverticulum, 2 after gastrectomy). In one patient, perforation occurred as a complication of the treatment of an esophageal rupture (which occurred during a balloon dilatation of benign stenosis) with a metallic stent.ResultsSeven covered biodegradable stents were implanted in five patients. Primary technical success was 100%. Clinical success (leak sealing) was achieved in four of the five patients (80%). Stent migration occurred in three patients. In two of these patients, the leak had been sealed by the time of stent migration, therefore no reintervention was necessary. In one patient an additional stent had to be implanted.ConclusionThe use of biodegradable covered stents for the treatment of anastomotic leaks or esophageal perforations is technically feasible and safe. The initial results are promising; however, larger number of patients will be required to evaluate the capability of these biodegradable stents in the future. The use of biodegradable material for coverage of the stent is essential.


CardioVascular and Interventional Radiology | 2012

Quality Improvement Guidelines for Transjugular Intrahepatic Portosystemic Shunt (TIPS)

Antonín Krajina; Petr Hulek; Tomáš Fejfar; Vlastimil Válek

Portal hypertension is a syndrome caused by increased resistance in the portohepatic circulation and an increase in the splanchnic vein blood supply. In the normal liver, the difference between pressures in the portal vein and the free hepatic veins or right atrium usually does not exceed 5 mm Hg. Portal hypertension is defined as a gradient larger than 6 mm Hg, but clinical complications seem to occur only when the pressure gradient exceeds 10–12 mm Hg. Wedged hepatic pressure measurement has two components. The portal component is the pressure transmitted from the hepatic sinusoids, and the systemic component is the blood pressure transmitted from the central veins. It is the portal component that causes the development of portal systemic collaterals. The term corrected sinusoidal pressure includes only the portal component and is calculated by subtracting the mean right atrial or inferior vena cava pressure from the wedged hepatic venous pressure. Wedged hepatic pressure is obtained through an end-hole catheter that is advanced into a hepatic vein until it can go no further. Alternatively, pressure can be measured through the wire channel of a double lumen balloon catheter inflated in a more central vein. Transjugular intrahepatic portosystemic shunt (TIPS) is the percutaneous method of creating a portosystemic shunt to decrease or treat portal hypertension. TIPS is a side-to-side shunt of a determined diameter designed to function as a partial shunt that preserves a portion of portal flow to the liver [2]. Flow through the completed shunt is assessed by comparing the degree of preferential filling of the shunt to the that of the portal vein branches and portosystemic collaterals (mainly in the gastric veins). The identification of hepatofugal (reversed) blood flow in portal vein branches (total shunting) is a sign of good flow through the shunt. Technical success is defined as a decrease of the portosystemic pressure gradient to 12 mm Hg or less, or a reduction of at least 20 %. Clinical success is defined as cessation of variceal bleeding, decrease of ascites, and conversion into diuretic-sensitive ascites, as well as improvement of liver function in patients referred for massive thrombosis of hepatic veins. Hepatic encephalopathy is defined as the complex of all cerebral dysfunctions that can occur during the course of serious liver disease. Clinical symptomatology, which as a rule is potentially reversible, ranges from disorientation, somnolence, and lethargy to sopor and coma. Hepatic encephalopathy has three forms: type A, associated with acute liver failure; type B, associated with portosystemic bypass without liver disease; and type C, or chronic, associated with liver cirrhosis.


Clinical Imaging | 2007

Crohn's disease at the small bowel imaging by the ultrasound–enteroclysis

Vlastimil Válek; Petr Kysela; M. Vavřková

Summary: Crohn’s disease is more likely a systemic disease governed by a shift in the immune response, thus affecting the whole MALT system. Its treatment should be as conservative as possible and surgery is usually taking place after complications like indolent fistulations, stenoses, bleeding, or bowel perforation started. Standard radiological methods to check the extent of the disease are loaded either with certain radiation exposure (enteroclysis, CT) or lack standardization (ultrasound). The aim of this small study was to evaluate the worth of ultrasound-enteroclysis in detecting the extent and complications of the Crohn’s disease in surgically treated patients. Material and methods: Since 1997, when we started with the ultrasound-enteroclysis, 246 surgical performances were involved into our study. Out of them, 181 had conventional abdominal intestinal ultrasound as well as conventional enteroclysis within 1 week. Remaining 65 cases were diagnosed by the ultrasound-enteroclysis. Intestinal ultrasound was performed on the Ultramark 3000 HDI device with autofocussable convex 5 MHz and linear 7.5 MHz probes or nowadays ATL 5000 HDI, 7–12 MHz linear probe. No contrast enhancement was used. Enteroclysis was done with the Micropaque suspension diluted 1:1 with HP-7000 300 ml with its application rate up to 75 ml/min followed by HP-7000 solution 2000 ml, application rate of 120 ml/min. The patients with ultrasound-enteroclysis were applied HP 7000 solution only (2000 ml, rate 100 ml/s) via an enteroclysis catheter. All investigations were video-recorded. Results: Consent with the per-operative finding was reached in 162 from 181 enteroclyses and in 169 of 181 ultrasounds. Ultrasound-enteroclysis was precise in 61 cases from 65. Among these, 60 patients had the recurrence during the treatment proved by clinical and laboratory results. This re-activation was clearly revealed in 38 from 43 cases by enteroclysis, 41 from 43 by US and in 16 from 17 by ultrasound-enteroclysis. From 30 patients that developed acute complication non-responding to the conservative therapy (abscesses, fistulas and intestinal obstructions) there were 18 from 20 accurately diagnosed by enteroclysis, only 12 from 20 by US and 9 from 10 by US-enteroclysis. The differences were either statistically non-significant or there were too small numbers to give sensible statistical results, but low sensitivity of ultrasound in complications (p = 0.05). Conclusion: US-enteroclysis seems to became the standard examination of patients with Crohn’s disease mainly in those with unclear conventional ultrasound. The most important fact is that this examination significantly decreases the radiation load when maintaining high sensitivity. This is very important namely in patients with Crohn’s disease that require life-long observation and repeated examinations. This examination is much more easy to standardize than the conventional US.


Diseases of The Esophagus | 2010

Combined treatment of achalasia – botulinum toxin injection followed by pneumatic dilatation: long‐term results

Radek Kroupa; Aleš Hep; Jiří Dolina; Vlastimil Válek; Z. Matyasova; Jitka Prokešová; J. Mrazova; Jaroslav Sedmík; I. Novotny

Injection of botulinum toxin (BT) and pneumatic dilatation are available methods in nonsurgical treatment of achalasia. Authors anticipate beneficial effect of prior BT injection on the success of pneumatic dilatation and duration of its effect. There are no long-term data available to assess efficacy of combined treatment. From 1998 to 2007, 51 consecutive patients (20 men and 31 women, age 24-83) with achalasia were included and prospectively followed up. Each patient received injection of 200 IU of BT into the lower esophageal sphincter (LES) during endoscopy and 8 days later pneumatic dilatation (PD) under X-ray control was performed. The follow-up was established every 3 months first year and then annually. The efficacy was evaluated by a questionnaire concerning patients symptoms and manometry. Results were compared with 40 historical controls (16 men and 24 women, age 26-80) treated by PD alone using the same method and follow-up. Fifty-one patients underwent combined treatment. Four patients failed in follow-up and were not included for analysis. The mean duration of follow-up was 48 months with range 12-96 months. Thirty-four of forty-seven (72%) patients were satisfied with results with none or very rare and mild troubles at the time of the last visit. Forty-one patients were followed up more than 2 years. Effect of therapy lasted in 75% (31/41) of them. In 17 patients, more than 5 years after treatment, effect lasted in 12 (70%). Mean tonus of LES before therapy was 29 mm Hg (10-80), 3 months after therapy decreased to 14 mmHg (5-26). The cumulative 5 years remission rate (+/-95% CI) in combined treated patients 69% +/- 8% was higher than in controls 50% +/- 9%; however it, was not statistically significant (P= 0.07). In control group 1, case of perforation (2.5%) occurred. Eight patients (17%) with relapse of dysphagia were referred to laparoscopic Heller myotomy with no surgical complication. The main adverse effect was heartburn that appeared in 17 patients (36%). Initial injection of BT followed by PD seems to be effective for long-term results with fewer complications. But the combined therapy is not significantly superior to PD alone.


Journal of Neuroradiology | 2004

Epidermoid tumor of the pons

R.N. Sener; Marek Mechl; Boleslav Prokeš; Vlastimil Válek

Epidermoid tumors originating from the brainstem are extremely rare. The authors report a patient with an intraaxial epidermoid tumor of the pons. The tumor involved most of the pons and had a small exophytic component.


World Journal of Gastroenterology | 2016

Contrast-enhanced ultrasonography in the evaluation of incidental focal liver lesions: A cost-effectiveness analysis

Miriama Šmajerová; Hana Petrášová; Jirina Little; Petra Ovesná; Tomáš Andrašina; Vlastimil Válek; Eva Nemcova; Barbora Miklošová

AIM To determine whether contrast-enhanced ultrasonography (CEUS) as the first-line method is more cost-effective in evaluating incidentally discovered focal liver lesions (FLLs) than is computed tomography (CT) and magnetic resonance imaging (MRI). METHODS Between 2010 and 2015, our prospective study enrolled 459 patients with incidentally found FLLs. The biological nature of FLLs was assessed by CEUS in all patients. CT or MRI examinations were added in unclear cases. The sensitivity and specificity of CEUS were calculated. The total costs of CEUS examinations and of the added examinations performed in inconclusive cases were calculated. Afterwards, the theoretical expenses for evaluating incidentally discovered FLLs using CT or MRI as the first-line method were calculated. The results were compared. RESULTS The total cost of the diagnostic process using CEUS for all enrolled patients with FLLs was 75884 USD. When the expenses for additional CT and MRI examinations performed in inconclusive cases were added, the total cost was 90540 US dollar (USD). If all patients had been examined by CT or MR as the first-line method, the costs would have been 78897 USD or 384235 USD, respectively. The difference between the cost of CT and CEUS was 3013 USD (4%) and that between MRI and CEUS was 308352 USD (406.3%). We correctly described 97.06% of benign or malignant lesions, with 96.99% sensitivity and 97.09% specificity. Positive predictive value was 94.16% and negative predictive value was 98.52%. In cases with 4 and more lesions, malignancy is significantly more frequent and inconclusive findings significantly less frequent (P < 0.001). CONCLUSION While the costs of CEUS and CT in evaluating FLLs are comparable, CEUS examination is far more cost-effective in comparison to MRI.


European Journal of Radiology | 2013

Contrast-enhanced ultrasonography compared to gray-scale and power doppler in the diagnosis of peripheral lymphadenopathy.

Radka Šlaisová; Karel Benda; Jiri Jarkovsky; Hana Petrášová; Petr Szturz; Vlastimil Válek

OBJECTIVES The aim of the study was to evaluate the ability of contrast-enhanced ultrasonography compared to gray-scale B-mode and power Doppler in distinction between benign and malignant lymphadenopathy. METHODS In a prospective study ultrasonography was performed in 133 patients with superficial lymphadenopathy (73 men, 60 women; mean age of 51 years, range: 18-86 years), who were examined for palpable mass in the neck, axilla or groin (104/133) and for clinical suspicion of lymphoma on the basis of positive PET/CT (29/133). 133 nodes were examined, subsequently preoperatively localized under ultrasound guidance and surgically removed; longitudinal to transverse ratio, location of nodal vessels by power Doppler and pattern of enhancement by contrast-enhanced ultrasonography with 1.5ml intravenous bolus of sulphur hexafluoride contrast agent were documented. The ultrasound findings were compared with the histology. RESULTS Of all the nodes extirpated, 33 were benign, 100 were malignant (40 metastases, 60 lymphomas). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of conventional techniques were 72%, 63.6%, 85.7%, 42.9%, 67.8% for longitudinal to transverse ratio; 73%, 60.6%, 84.9%, 42.6%, 68.3% for power Doppler versus 98.0%, 54.5%, 86.7%, 90.0%, 76.3% for contrast-enhanced ultrasonography according to Receiver Operating Characteristic analysis. CONCLUSIONS Receiver Operating Characteristic analysis confirmed higher degree of diagnostic accuracy of contrast-enhanced ultrasonography in comparison with conventional techniques. Evaluation of nodal perfusion after intravenous administration of microbubble contrast agent can be helpful in differentiation of benign from malignant nodes.


Gut and Liver | 2010

Multimodal Oncological Therapy Comprising Stents, Brachytherapy, and Regional Chemotherapy for Cholangiocarcinoma

Tomáš Andrašina; Vlastimil Válek; Jiří Pánek; Zdeněk Kala; Igor Kiss; Štěpán Tuček; Pavel Šlampa

BACKGROUND/AIMS To prospectively evaluate our palliative management of unresectable cholangiocarcinoma (CC) treated with tailored multimodal oncological therapy. METHODS Between January 2005 and January 2010, 50 consecutive patients with unresectable CC and jaundice were palliated with percutaneous drainage. Forty-three patients underwent metallic-stent implantation followed by brachytherapy. Patients were divided into two arms: the intra-arterial chemotherapy arm (IA arm, n=17) consisted of patients treated with locoregional treatment (IA admission of Cisplatin and 5-fluorouracil, or chemoembolization with Lipiodol) and/or systemic chemotherapy, while the systemic chemotherapy arm (IV arm, n=23) included all the other patients, who were treated only with systemic chemotherapy. RESULTS In total, 78 metal self-expandable stents were placed. Hilar involvement with mass-forming and periductal infiltrating types of CC (84%) was predominant. The average number of percutaneous interventional procedures was 11.61 per patient (range, 4-35). The median overall survival from diagnosis of disease for all patients was 13.5 months (range, 11.0-18.8 months). The median overall survival times were 25.2 months (range, 15.2-31.3 months) and 11.5 months (range, 8.5-12.6 months) in the IA and IV arms, respectively (p<0.05). The 1-, 2-, and 3-year survival rates in the IA and IV arms were 88.2%, 52.9%, and 10.1% and 43.5%, 25.4, and 0%, respectively. There were no major complications (WHO III/IV) due to interventional procedures. CONCLUSIONS We could reach acceptable prognosis in patients with unresectable CC using complex tailored oncological therapy. However, the main limitations of prolonging survival are performance status, patient compliance and the maintaining of biliary tract patency.


CardioVascular and Interventional Radiology | 2013

Quality Improvement Guidelines for Transcatheter Embolization for Acute Gastrointestinal Nonvariceal Hemorrhage

Vlastimil Válek; Jakub Husty

Transcatheter embolization is defined as the intravascular deposition of particles, liquid, or mechanical agents to produce vessel occlusion. Technical success is typically defined as a cessation of active contrast media extravasation (if present before embolization) from the bleeding site at the end of the procedure. In presence of only indirect signs, it is considered as complete occlusion of pathologically changed arteries or pseudoaneurysms. Clinical success definition varies greatly between the various reports in the literature. It is usually associated with the resolution of signs and symptoms of bleeding in a defined time period (mostly 30 days). Some studies also include secondary clinical success after repeated embolization in case of recurrent bleeding. Persistence of melena or hematemesis within 12–24 h after the procedure should not be considered a clinical failure if not associated with clear laboratory or clinical signs of blood loss and should not indicate the need for a reintervention. Acute significant bleeding is generally considered as bleeding requiring transfusion of at least 4 units of blood within 24 h or causing signs of hemodynamic instability and shock (hypotension systolic BP of 100) [8, 9, 10].


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2012

Laparoscopic radiofrequency ablation of functioning pancreatic insulinoma: video case report.

Vladimír Procházka; Jan Hlavsa; Tomáš Andrašina; Karel Starý; Katarina Můčková; Zdeněk Kala; Vlastimil Válek

Insulinomas are the most common functioning endocrine tumors of the pancreas. Most of them are well-differentiated tumors, with benign or uncertain behavior at the time of diagnosis. Surgery is considered to be the only curative treatment modality. We present the first case report of a 75-year-old woman with functioning insulinoma of the pancreatic body, which was destroyed by laparoscopic-assisted radiofrequency ablation. Hypoglycemic paroxysms disappeared immediately after surgery. The postoperative course was uneventful. The patient was discharged on the eighth postoperative day. There was a new onset of diabetes mellitus, without any further hypoglycemic paroxysm from surgery to the present—4 months. Laparoscopic-assisted radiofrequency ablation is shown to be a feasible and safe method for the treatment of functioning pancreatic insulinoma.

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