Percutaneous Sclerotherapy of Large and Giant Non-Parasitic Liver Cysts under Ultrasound Guidance

The dissertation is devoted to improving the tactics of surgical treatment of large and giant non-parasitic liver cysts. It addresses the diagnosis of these lesions using a combination of B-mode ultrasound, color duplex scanning of hepatic vessels, and three-dimensional ultrasound reconstruction, together with radiological, laboratory, and morphological methods. A unified technique of percutaneous sclerotherapy under ultrasound guidance is developed and substantiated: criteria for patient selection and indications and contraindications are defined with regard to the localization, extent, size, and complications of the cysts, and the technical equipment, puncture access, interventional stage, and stage of sclerotherapy are described. A comparative analysis is carried out of the immediate and remote results of percutaneous, open surgical, and laparoscopic treatment, as well as an analysis of complications and measures for their prevention.

Relevance of the Topic

With the improvement of the diagnostic capabilities of ultrasound examination (US) and computed tomography (CT), the rate of in-life diagnosis of true liver cysts has risen to 4% - 7% (Kornprat P. et al., 2004). The development and introduction of interventional techniques into surgery has stimulated the elaboration of fundamentally new approaches to their treatment through the use of methods performed under visual guidance (Gal'perin E.I. et al., 2001; Conzo G. et al., 2001).

In non-parasitic liver cysts (NPLC) of small and medium size (3 -7 cm), a clear tendency is currently observed toward their elimination by a minimally invasive (percutaneous) method under ultrasound guidance (Borsukov A.V., 2004; Pozniczek M. et al., 2004).

Regarding the choice of the surgical treatment method for large and giant cysts measuring 10 cm or more in diameter, there are different points of view, often acquiring a polar character. At the same time, the boundaries of indications for traditional surgical, minimally invasive laparoscopic, or percutaneous sclerotherapy (PST) are practically undefined (Ikramov R.Z., 1992; Akhaladze G.G. et al., 1999; Vishnevskii V.A. et al., 2003; Tanaka S. et al., 1998; Eriguchi N. et al., 2001; Tucker O.N. et al., 2005). This is facilitated by the absence of a unified classification of non-parasitic liver cysts of large and giant size, and by the problem of their differential diagnosis from cystic-solid liver lesions, which creates significant difficulties in choosing a rational therapeutic approach for this category of patients (Ershov K.G., 1999; Kuntsevich G.I., 1999; Blonski W.C. et al., 2006).

Proponents of classical surgical treatment are convinced that the larger the cyst, the more frequent the indications for open surgical intervention (Zollinger R., Zollinger R.-Jr., 2002; Martin I.J. et al., 1998).

The improvement of the technique and methods of laparoscopic surgical interventions has determined, according to a number of authors, the leading role of the laparoscopic method in the treatment of NPLC (Strekalovskii V.P. et al., 1997; Vishnyakov D.V., 2003; Tan Y.M. et al., 2005). Unfortunately, the limited experience of most specialists concerns mainly medium-sized cysts, and isolated observations of large and giant NPLC, included by them in generalized analyses, do not allow an objective assessment of the effectiveness of this treatment method for the indicated category of cysts (Lobakov A.I. et al., 2003; Starkov Yu.G. et al., 2006; Cappellani A. et al., 2002; Szabo L.S. et al., 2006).

It is important to note that the recurrence rate of the disease in the treatment of large and giant NPLC without performing anatomical resection by the traditional surgical method reaches 29%, and after laparoscopic operations - 36% (Morino M. et al., 1996; Martin I.J. et al., 1998).

Most specialists consider it advisable to begin the treatment of large NPLC with percutaneous puncture sclerotherapy under ultrasound guidance, and only in the event of its failure to resort to other types of surgical interventions. At the same time, the effectiveness of percutaneous transcatheter sclerotherapy of non-parasitic cysts measuring 5 -6 cm in diameter exceeds 90% (Gavrilin A.V., 1999; Tikkakoski T. et al., 1996). The number of reports on the successful use of percutaneous puncture-catheter techniques in the treatment of large and giant NPLC is small (Gavrilin A.V. et al., 2005; Larssen T.B. et al., 1997; Blonski W.C. et al., 2006).

The approach to the choice of surgical treatment method in complicated clinical course of NPLC is ambiguous. The results of successful radical minimally invasive treatment of complicated large liver cysts are presented only in isolated publications (Lotov A.N., 1998; Gavrilin A.V., 1999; Yoshida H. et al., 2003).

The diversity of views on the assessment of the most effective variants of percutaneous sclerotherapy, as well as differences in tactical and technical principles, do not promote the wider introduction of the method into surgical practice. In particular, there are no clear delineations of indications for choosing the method of surgical treatment of NPLC depending on their size, extent, and localization, the character of concomitant pathology and the age of patients, as well as the anticipated duration of treatment. Complications, measures of their prevention and elimination are not analyzed. This creates significant difficulties in conducting a comparative analysis of the effectiveness of percutaneous treatment of large and giant NPLC.

The aim of the work is to improve the tactics of surgical treatment of large and giant NPLC through the rational application of a unified technique of percutaneous sclerotherapy under ultrasound guidance.

Research Objectives

1. To determine the criteria for patient selection for percutaneous sclerotherapy of large and giant NPLC under ultrasound guidance based on the comparison of clinical data, the results of comprehensive ultrasound examination, and laboratory parameters of blood and cyst contents.

2. To determine the indications and contraindications for percutaneous treatment of large and giant NPLC depending on their localization, extent, size, and complications.

3. To determine the average duration and effectiveness of percutaneous sclerotherapy of various types of large and giant NPLC.

4. To conduct a comparative analysis of the treatment results of large and giant NPLC after percutaneous, open surgical, and laparoscopic interventions in the early postoperative period.

5. To study the immediate and remote results of percutaneous sclerotherapy of large and giant NPLC under ultrasound guidance.

Main Statements Defended

• Comprehensive ultrasound examination of the liver, including B-mode ultrasound examination of the abdominal organs, color duplex scanning of liver vessels, and three-dimensional ultrasound reconstruction of the liver, is the principal method of differential diagnosis of large and giant NPLC, contributes to the optimization of the choice of therapeutic tactics, and increases the safety of performing percutaneous sclerotherapy under ultrasound guidance.

• Percutaneous sclerotherapy under ultrasound guidance is an effective minimally invasive method of treating large and giant NPLC, the duration and tactical-technical variants of which depend on the type of clinical course of the disease and the size of the lesion, and can be considered as an independent and definitive method of eliminating this pathology.

• The assessment of the results of percutaneous sclerotherapy should be carried out according to dynamic ultrasound follow-up data, taking into account the clinical picture, with the aim of early detection of disease recurrence, as well as the identification of categories of patients with an increased risk of developing clinically complicated course of the disease against the background of multiple NPLC or polycystic liver disease, with the possibility of staged minimally invasive treatment in such patients.

Scientific Novelty

The sequence and expediency of the application of modern diagnostic research methods in the algorithm of preoperative examination of patients with large and giant NPLC have been determined for resolving tactical and technical issues in choosing the method of their surgical treatment.

For the first time, based on high-technology US techniques (color duplex scanning, three-dimensional reconstruction), an algorithm of diagnostic studies has been proposed for planning and performing percutaneous puncture-catheter therapeutic interventions in NPLC.

For the first time, a unified technique of percutaneous sclerotherapy of large and giant NPLC under ultrasound guidance has been developed.

For the first time, the features, as well as hazards and complications in the process of percutaneous treatment of large and giant NPLC have been assessed, and a principal system of measures for their prevention and treatment has been developed.

For the first time, based on the statistical analysis of immediate and remote results, an objective assessment of the effectiveness of percutaneous puncture-catheter treatment of large and giant NPLC under ultrasound guidance has been given, and a comparison of its immediate results with other surgical methods of treatment has been carried out.

Practical Significance

Based on the data of comprehensive ultrasound examination and dynamic follow-up of patients, indications and contraindications for percutaneous treatment of various types of large and giant NPLC have been substantiated.

An analysis has been conducted of the duration of treatment, immediate and remote results of percutaneous sclerotherapy of large and giant NPLC, with the presentation of the obtained results in the form of "average bed-days" and terms of dynamic outpatient ultrasound follow-up for the rational use of this technique in practical health care.

Based on the analysis of errors, hazards, and complications of percutaneous sclerotherapy of large and giant NPLC, measures for their prevention and minimally invasive elimination have been developed, without resorting to open surgical intervention.

A unified technique of percutaneous sclerotherapy of large and giant NPLC under ultrasound guidance in patients with a high risk of other operative treatment methods has been developed and introduced into the clinical practice of the A.V. Vishnevskii Institute of Surgery.

Approbation of the Work

The main statements of the work were reported and discussed at the scientific conference of young scientists dedicated to the 60th anniversary of the A.V. Vishnevskii Institute of Surgery, Moscow, 2005; at the International Youth Medical Congress "St. Petersburg Readings," St. Petersburg, 2005 (second-degree diploma); and were presented as a poster report at the XIII International Congress of Hepatobiliary Surgeons of CIS Countries "Current Problems of Surgical Hepatology," Kazakhstan, Almaty, 2006.

Implementation in Practice

The technique of percutaneous sclerotherapy of large and giant NPLC under ultrasound guidance proposed in the work, taking into account the data of comprehensive preoperative examination, has been introduced into the practice of the Department of Abdominal Surgery and the Department of Ultrasound Diagnostics of the A.V. Vishnevskii Institute of Surgery and can be used in surgical departments of the abdominal profile, as well as for training specialists in the field of percutaneous minimally invasive interventions.

Publications

Six scientific works have been published on the topic of the dissertation.

Volume and Structure of the Dissertation

The work is presented on 114 pages of typewritten text and consists of an introduction, 5 chapters, conclusions, practical recommendations, and a list of references. The work is illustrated with 10 tables and 25 figures. The list of references contains 184 literary sources (85 domestic and 99 foreign).

I express my deep gratitude to the Director of the Federal State Institution "A.V. Vishnevskii Institute of Surgery of Rosmedtekhnologii," Academician of RAMS Vladimir Dmitrievich Fyodorov, and to the administration of the Institute for the opportunity to carry out the present work within the walls of a leading scientific and medical institution of surgical profile.

Words of sincere gratitude to my academic supervisors: Laureate of the Prize of the Government of the Russian Federation, Doctor of Medical Sciences Anatolii Vasilyevich Gavrilin, and Laureate of the State Prize of the Russian Federation and Laureate of the Prize of the Government of the Russian Federation, Doctor of Medical Sciences, Professor Vladimir Aleksandrovich Vishnevskii, for valuable advice, comprehensive support, and constant assistance in the course of scientific and practical activity.

Deep gratitude to the Head of the Department of Ultrasound Diagnostics, Doctor of Medical Sciences, Professor Galina Ivanovna Kuntsevich, for objective remarks and comprehensive assistance during the work on the dissertation.

I thank all the staff of the Department of Abdominal Surgery, headed by Corresponding Member of RAMS, Doctor of Medical Sciences, Professor Valerii Alekseevich Kubyshkin, as well as the Department of Pathomorphology and the laboratory divisions of the A.V. Vishnevskii Institute of Surgery for joint work and comprehensive participation in the collection and evaluation of the clinical material.

Sincere thanks to all the staff of the Department of Ultrasound Diagnostics for their benevolence, friendly support, and assistance in professional activity and everyday life.