Petko Karagyozov

Prof. Petko Karagyozov

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 January 2021 in World Journal of Hepatology
Verified
Journal Article
Open access
IBIrina Boeva
Irina Boeva
PKPetko Karagyozov
Petko Karagyozov
ITIvan Tishkov
Ivan Tishkov
Post-liver transplant biliary complications: Current knowledge and therapeutic advances

16 January 2019 in World Journal of Gastrointestinal Endoscopy
Verified
Journal Article
Open access
PKPetko Karagyozov
Petko Karagyozov
IBIrina Boeva
Irina Boeva
ITIvan Tishkov
Ivan Tishkov
Due to the need for improvement in the diagnosis and minimally invasive therapy of the bile duct disorders new technologies for cholangioscopy have been recently developed. Per-oral cholangioscopy has become an important diagnostic and therapeutic tool leading to avoidance of aggressive and unnecessary surgery in many clinical scenarios. This paper focuses on the newly developed SpyGlass DS technology, its advantages, and the technique of single-operator cholangioscopy (SOC), biliary indications and possible adverse events. We also review the available literature; discuss the limitations and future expectations. Digital SOC (D-SOC) is a useful technique, which provides endoscopic imaging of the biliary tree, optical diagnosis, biopsy under direct vision and therapeutic interventions. The implementations are diagnostic and therapeutic. Diagnostic indications are indeterminate biliary strictures, unclear filling defects, staging of cholangiocarcinoma, staging of ampullary tumors (extension into the common bile duct), unclear bile duct dilation, exploring cystic lesions of the biliary tree, unexplained hemobilia, posttransplant biliary complications. Therapeutic indications are lithotripsy of difficult stones, retrieval of migrated stents, foreign body removal, guide wire placement, transpapillary gallbladder drainage and endoscopic tumor ablative therapy. Most studied and established indications are the diagnosis of indeterminate biliary stricture and intraductal lithotripsy of difficult stones. The adverse events are not different and more common compared to those of Endoscopic retrograde cholangiopancreatography (ERCP) alone. D-SOC is a safe and effective procedure, adjunct to the standard ERCP and the newly available digital technology overcomes many of the limitations of the previous generations of cholangioscopes.

20 July 2022 in Endoscopy
Verified
Journal Article
Open access
PDF file
DJDavid Michaël de Jong
David Michaël de Jong
PSPauline M. C. Stassen
Pauline M. C. Stassen
BKBas Groot Koerkamp
Bas Groot Koerkamp
MEMark Ellrichmann
Mark Ellrichmann
PKPetko Karagyozov
Petko Karagyozov
OGon behalf of the European Cholangioscopy study group
on behalf of the European Cholangioscopy study group
Background Confirming the diagnosis, invasiveness, and disease extent of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is challenging. The aim of this study was to summarize the literature on the efficacy and safety of peroral pancreatoscopy (POP) in the diagnosis of IPMN, including the impact of pre- and intraoperative POP on the management of IPMN. Methods The EMBASE, Medline Ovid, Web of Science, Cochrane CENTRAL, and Google Scholar databases were systematically searched for articles. Eligible articles investigated cohorts of patients who underwent POP for (suspected) IPMN. Results 25 articles were identified and included in this review; with 22 of these reporting on the diagnostic yield of POP in IPMN and 11 reporting on the effect of pre- or intraoperative POP on clinical decision-making. Cannulation and observation rates, and overall diagnostic accuracy were high across all studies. Frequently reported visual characteristics of IPMN were intraductal fish-egg-like lesions, hypervascularity, and granular mucosa. Overall, the adverse event rate was 12 %, primarily consisting of post-endoscopic retrograde cholangiopancreatography pancreatitis, with a pooled rate of 10 %, mostly of mild severity. Regarding the impact of POP on clinical decision-making, POP findings altered the surgical approach in 13 %–62 % of patients. Conclusion POP is technically successful in the vast majority of patients with (suspected) IPMN, has a consistently high diagnostic accuracy, but an adverse event rate of 12 %. Data on intraoperative pancreatoscopy are scarce, but small studies suggest its use can alter surgical management. Future studies are needed to better define the role of POP in the diagnostic work-up of IPMN. * Shared first authorship Received: 06 December 2021 Accepted after revision: 23 May 2022 Accepted Manuscript online: 03 June 2022 Article published online: 20 July 2022 © 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/) Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

16 December 2021 in World Journal of Gastrointestinal Endoscopy
Verified
Journal Article
Open access
PKPetko Karagyozov
Petko Karagyozov
ITIvan Tishkov
Ivan Tishkov
IBIrina Boeva
Irina Boeva
KDKiril Draganov
Kiril Draganov
Endoscopic retrograde cholangiopancreatography (ERCP) with stenting is the treatment modality of choice for patients with benign and malignant bile duct obstruction. ERCP could fail in cases of duodenal obstruction, duodenal diverticulum, ampullary neoplastic infiltration or surgically altered anatomy. In these cases percutaneous biliary drainage (PTBD) is traditionally used as a rescue procedure but is related to high morbidity and mortality and lower quality of life. Endoscopic ultrasound-guided biliary drainage (EUS-BD) is a relatively new interventional procedure that arose due to the development of curvilinear echoendoscope and the various endoscopic devices. A large amount of data is already collected that proves its efficacy, safety and ability to replace PTBD in cases of ERCP failure. It is also possible that EUS-BD could be chosen as a first-line treatment option in some clinical scenarios in the near future. Several EUS-BD techniques are developed EUS-guided transmural stenting, antegrade stenting and rendezvous technique and can be personalized depending on the individual anatomy. EUS-BD is normally performed in the same session from the same endoscopist in case of ERCP failure. The lack of training, absence of enough dedicated devices and lack of standardization still makes EUS-BD a difficult and not very popular procedure, which is related to life-threatening adverse events. Developing training models, dedicated devices and guidelines hopefully will make EUS-BD easier, safer and well accepted in the future. This paper focuses on the technical aspects of the different EUS-BD procedures, available literature data, advantages, negative aspects and the future perspectives of these modalities.

1 January 2020 in Current Drug Metabolism
Verified
Journal Article
Closed access
PDF file
IDInna Dobreva
Inna Dobreva
PKPetko Karagyozov
Petko Karagyozov
The liver represents the major site of drug metabolism, i.e. the key organ in the processes of detoxification and elimination of drugs from the organism. It is therefore often affected by toxic metabolites and suffers sometimes fatal consequences. The spectrum of pathologies differs by the cell type primarily damaged and the group of the cholangiopathies includes those conditions affecting the bile duct epithelium or the cholangiocytes. They can range from transient cholestasis to vanishing bile duct syndrome and sclerosing cholangitis, both leading eventually to the development of biliary fibrosis and cirrhosis. In tins review article, we focus on the etiology, predisposing factors,clinical manifestations, and histopathological characteristics of bile duct injury as a consequence of drug treatment and discuss separately the different bile duct pathologies.

3 January 2019 in Endoscopy International Open
Verified
Journal Article
Open access
PDF file
PKPetko Karagyozov
Petko Karagyozov
ITIvan Tishkov
Ivan Tishkov
ZGZhenya Georgieva
Zhenya Georgieva
IBIrina Boeva
Irina Boeva
DTDimitar Tzankov
Dimitar Tzankov
An intraluminal duodenal diverticulum (IDD) is a rare congenital anomaly, which is a result of incomplete recanalization of the foregut lumen during embryonic development. Most patients are asymptomatic. Symptoms usually occur after the third decade of life and mainly include epigastric pain, nausea, vomiting, or bloating. Less commonly, IDD may complicate with bleeding, duodenal obstruction, or acute pancreatitis. We present a case of IDD, manifested for a first time in adult with acute biliary obstruction and mild pancreatitis after laparoscopic cholecystectomy for acute calculous cholecystitis, successfully managed with endoscopic retrograde cholangiopancreatography (ERCP).