Use Of Flexible Endoscopes Research Articles

Practical techniques for safely removing long-term implanted ventricular catheters to minimize bleeding.

Removing ventricular catheters, particularly those implanted for extended periods, poses significant challenges for neurosurgeons due to potential complications such as bleeding from adhesions to the ependyma or choroid plexus. This study aimed to review various techniques for safely removing ventricular catheters, emphasizing methods that minimize the risk of hemorrhagic complications. A comprehensive narrative review focused on techniques developed and documented in the literature for safely detaching ventricular catheters adhered to brain structures. Various techniques have been identified that enhance the safety of catheter removal. Notably, the use of monopolar diathermy to coagulate and release adhesions has proven effective. Innovations such as insulated suction devices and the strategic use of flexible endoscopes have also contributed to safer removal procedures, minimizing the risk of damaging surrounding cerebral tissue and preventing catastrophic hemorrhage. The removal of ventricular catheters, especially those with long-term implantation, requires precise and cautious techniques to avoid severe complications. The study underscores the importance of adopting advanced surgical techniques and the continuous evolution of safer practices in neurosurgery. These methods not only ensure patient safety but also facilitate the handling of potentially complex and life-threatening situations during catheter removal.

Personalized Prediction of Patient Radiation Exposure for Therapy of Urolithiasis: An Application and Comparison of Six Machine Learning Algorithms.

The prediction of radiation exposure is an important tool for the choice of therapy modality and becomes, as a component of patient-informed consent, increasingly important for both surgeon and patient. The final goal is the implementation of a trained and tested machine learning model in a real-time computer system allowing the surgeon and patient to better assess patient's personal radiation risk. In summary, 995 patients with ureterorenoscopy over a period from May 2016 to December 2019 were included. According to the suggestions based on actual literature evidence, dose area product (DAP) was categorized into 'low doses' ≤ 2.8 Gy·cm2 and 'high doses' > 2.8 Gy·cm2 for ureterorenoscopy (URS). To forecast the level of radiation exposure during treatment, six different machine learning models were trained, and 10-fold crossvalidated and their model performances evaluated in training and independent test samples. The negative predictive value for low DAP during ureterorenoscopy was 94% (95% CI: 92-96%). Factors influencing the radiation exposure were: age (p = 0.0002), gender (p = 0.011), weight (p < 0.0001), stone size (p < 0.000001), surgeon experience (p = 0.039), number of stones (p = 0.0007), stone density (p = 0.023), use of flexible endoscope (p < 0.0001) and preoperative stone position (p < 0.00001). The machine learning algorithm identified a subgroup of patients of 81% of the total sample, for which highly accurate predictions (94%) were possible allowing the surgeon to assess patient's personal radiation risk. Patients without prediction (19%), the medical expert can make decisions as usual. Next step will be the implementation of the trained model in real-time computer systems for clinical decision processes in daily practice.

Single-use products in endoscopy-from consumables to single-use scopes

Wie in diversen Fallberichten und prospektiven Studien beschrieben stellen flexible Endoskopien einen potenziellen Risikofaktor für klinisch relevante Infektionen dar. Bei den Übertragungswegen sind dabei endogene Infektionen, ausgelöst durch eine Verschleppung der körpereigenen Mikroorganismen des jeweiligen Patienten, von exogenen Infektionen, die durch eine Übertragung von kontaminiertem Material oder Endoskopen entstehen, zu unterscheiden. Um das Problem der steigenden Zahl bekannter, exogener Infektionen zu minimieren, wurden von der Industrie Einmalendoskope entwickelt und für den klinischen Einsatz zertifiziert. Einmalbronchoskope sind bereits seit Jahren Bestandteil der klinische Routineversorgung, Einmalduodenoskope wurden erst kürzlich zugelassen. Die Nutzung von Einmalendoskopen stellt vordergründig eine finanzielle Mehrbelastung des Gesundheitssystems dar. Neben den reinen Sachkosten der Einmalendoskope sind aber insbesondere auch die vermeidbaren Kosten klinische relevanter Infektionen, wie verlängerter Krankenhausaufenthalt, intensivmedizinische Behandlung und Folgeeingriffe, in der Gesamtkalkulation zu berücksichtigen. Unabhängig von betriebs- und volkswirtschaftlichen Überlegungen steht die Patientensicherheit im Zentrum pflegerischen und ärztlichen Handelns.

Flexible endoscopy versus direct laryngoscopy for localising impacted pharyngeal foreign bodies in emergency department: A randomised cross-over manikin pilot study

Background: Direct laryngoscopy is often poorly tolerated in patients with foreign body ingestion. The use of flexible endoscopes, which are reported to be better tolerated, was described. However, studies on endoscopy usage by emergency physicians are lacking. Objective: This study evaluates whether using a bronchoscope is as effective as the direct laryngoscopy for localising pharyngeal foreign bodies by emergency physicians. Methods: This was a randomised cross-over manikin study conducted on 32 emergency physicians. Four foreign bodies were placed at the oropharynx, vallecula, arytenoid and post-cricoid area of a manikin. Participants, being randomised into two groups, examined the pharynx with a bronchoscope and a direct laryngoscope in designated orders. The primary outcome was the complete visualisation rate defined as visualising all the four foreign bodies within the time limit. Secondary outcomes included participants-rated difficulty scores, device preferences, the time needed for complete visualisation and cumulative success rates. Results: Complete visualisation rate was significantly higher using the bronchoscope (93.8%) than the direct laryngoscope (62.5%) p = 0.02. The overall difficulty score was lower using the bronchoscope (median 4, interquartile range: 3–5) than the direct laryngoscope (median 6, interquartile range: 5–8), p &lt; 0.001. The bronchoscope was the preferred method for overall examination (71.9%) over the direct laryngoscope (28.1%), p = 0.001. There were no significant differences in times needed for complete examination for the bronchoscope (median 73.6 s, interquartile range: 54.7–97.7 s) and the direct laryngoscope (median 82.2 s, interquartile range: 40.1–120 s), p = 0.9, and cumulative success rates, p = 0.081. Conclusion: The bronchoscope was associated with an increased complete visualisation rate and was the easier and preferred method for pharyngeal examination.

ETV and choroid plexus coagulation: a critical analysis

Objective: To analyze the current medical literature regarding the addition of choroid plexus coagulation (CPC) to an endoscopic third ventriculostomy (ETV), with the aim of improving its efficacy. The historical background and rationale for these procedures are also presented. Methods: A Pubmed search using MeSH terms “choroid plexus coagulation” and “endoscopic third ventriculostomy” was performed in October 2020, retrieving 107 papers. A summary of the findings of these articles is provided, with a particular emphasis on the ones with higher scientific evidence levels (two systematic reviews with meta-analyses and three prospective studies with large case series). The following questions should be answered: “Does CPC add to the success rate of ETV, and in comparison, with shunts?” “Which clinical and surgical factors contribute to positive results of CPC / ETV?” And “Does CPC add morbidity / mortality to endoscopic surgery?” Results/Discussion: There is significant evidence to support that CPC adds up to the success rates of ETV; this is particularly true in the context of the so-called “communicating hydrocephalus”, especially for patients with post-infectious and post-hemorrhagic hydrocephalus. Nevertheless, patients with “obstructive” etiologies also benefit from CPC + ETV. Pooled success was estimated at around 63%, and successful results as measured by shunt-free rates ranged from 49% to 75%. The highest benefit was observed in patients above 6 months of age. Other factors that might have an influence in success rates include extent of cauterization and, understandably, the use of flexible endoscopes, that allow for coagulating greater amounts of choroid plexus. Morbidity rates were not affected and remained similar to ETV and other neuroendoscopic procedures alone (around 1% overall). Conclusion: The addition of CPC to an ETV can be quite beneficial and improve its success rate; this combination is certainly useful to avoid shunts. Nevertheless, patient selection and a thorough knowledge of the surgical indications and techniques is still required to achieve satisfactory results.

Selective Neuroendoscopic Resection of the Choroid Plexus as an Alternative Technique for Optimizing the Standard Endoscopic Approach to Hydrocephalus

In the past four decades, enormous advances have been made in the neuroendoscopic techniques, along with improvement of illumination, and the development of effective instruments. As a result, endoscopic third ventriculostomy (ETV) and choroid plexus cauterization (CPC) have become consolidated techniques for the treatment of hydrocephalus. In particular, endoscopic cauterization of the choroid plexus has increased the effectiveness of hydrocephalus treatment in combination with ETV. In the past decade, the use of flexible endoscopes has enabled surgeons to resect even the temporal segment of the choroid plexus at the lateral ventricles, which has increased the success of treatment. In this technical note, we describe CPC with the use of a rigid endoscope, which we used to selectively disconnect the glomus of the choroid plexus, in addition to choroid plexus coagulation, as an alternative way to facilitate ETV. This new procedure optimized the visualization of the choroid plexus and the temporal horn and prevented additional difficulties in coagulation of this mobile region of the choroid plexus in selected patients. To achieve the best outcome, avoid bleeding, and optimize the standard technique, it was important to recognize both the classical anatomic structure of the choroid plexus and some variations, and previous expertise in ETV and CPC were necessary. We demonstrate that resection of the glomus of the choroid plexus in selected patients is safe and feasible.

Capacity of flexible endoscopy in subepithelial esophageal tumors

Aim of the study was to investigate the results of endoscopic diagnostics and peroral operative endoscopy in subepithelial esophageal tumors. Material and methods. Data of 21 patients underwent flexible endoscopic interventions for subepithelial esophageal tumors (SET) from 2016 till 2019 were analyzed. Main endoscopic methods to reveal and characterize tumors preoperatively are examination in white light, narrow light spectrum imaging, radial endoscopic ultrasonographic scanning. Tumors from 8 till 40 mm in maximal dimension removed by endoscopic mucosal resection (2 tumors in 1 patient), tunnel dissection (13 cases) or endoscopic submucosal dissection (7 cases). The additional endoscopic ultrasonography was demanded intraoperatively in 2 cases of difficult tumor location and blurry visualization. Results and discussion. Subepithelial esophageal tumors are mainly diagnosed occasionally in patients without symptoms related to tumor. Suspicion of the tumor was based on routine esophagogastroduodenoscopy. Following endoscopic ultrasonography of planned esophageal segment allowed rejecting or confirming the lesion (21 patients), evaluating its echoscopic structure, size, growth direction, intramural location and connection to wall layers to make an assumption related to tumor morphology, to plan way of tumor removal. We choose interventions in depends on combination of available tumor features. Technical success of endoscopic interventions with use of flexible endoscope under this approach is noted in all the patients. So endoscopic methods are important for primary and detailed diagnostics and also effective for operative treatment in cases of appropriate indications.

Duodenoscope-Associated Bacterial Infections: A Review and Update.

Physicians depend on the use of flexible endoscopes for delivery of vital care that is morbidity sparing compared to surgical alternatives. Iatrogenic infection is a well-documented complication of therapeutic endoscopy. Recent emergence of unique antimicrobial resistance patterns and molecular "fingerprinting" of bacteria harken a new era in duodenoscope-related infections which occur in spite of compliance with device manufacturer-recommended protocols for high-level disinfection (HLD). Further studies suggest that these protocols are likely inadequate. Endoscopic retrograde cholangiopancreatography (ERCP) remains critical in the provision of minimally invasive diagnostic, therapeutic, and palliative care for patients with pancreaticobiliary disease. This manuscript reviews the history of duodenoscope-related infections, current challenges to scope reprocessing, and recommendations from regulatory agencies.

Use of flexible endoscope for evaluation of swallowing

Use of flexible endoscope for evaluation of swallowing

Trans Oral-Substernum Incision Thoracic Endoscopic Surgery: A Minimally Invasive Endoscopic Approach in Thoracic Surgery

Flexible endoscope is used in Natural Orifice Trans-luminal Endoscopic Surgery. Cervical incision thoracic surgery has recently been described. The use of a flexible endoscope through a natural orifice into the thoracic cavity still remains ethically doubtful. The authors present a surgical experimental study using a flexible endoscope through oral-substernum incision for the exploration of both the thoracic cavity in dog model. An experimental work on 5 male mongrel dogs was initiated. Through a small incision at oral floor, we performed simultaneous exploration of the pleural cavities. Identification and biopsies of pleural and lung was performed. None chest tube was placed in the thoracic cavity at the end of all pleural procedures. The potential advantages of this approach are exploration of the thoracic cavity and the performance of several thoracic interventions through oral floor. The flexible endoscope could become a surgical tool for thoracic surgery. The treatment of lung cancer and other thoracic tumors usually involves thoracic surgeries. Cancer staging is a necessary step before cancer treatment. Mediastinal lymph nodes, pleural biopsies and lung biopsies are frequently needed for staging tumors. Despite the development of less invasive techniques, such as trans-bronchial needle aspiration (TBNA), endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), and more recently, endobronchial ultrasoundguided fine-needle aspiration (EBUS-FNA), mediastinoscopy and video-thoracoscopy still remain the more satisfactory and commonly performed invasive techniques for mediastinal and pleural staging of thoracic tumors [1,2]. The development of thoracoscopic approaches during the early 1990s excited thoracic surgeons due to multiple advantages of this technique. Thoracoscopy unquestionably decreased the length of hospital stay, hospital cost, and rate of scar complications; and provided some cosmetic advantages. However, it did not significantly reduce postoperative pain. Thoracic ports and chest tubes are a major cause of persistent pain [3]. Minimally invasive techniques in thoracic surgery are evolving. And several recent thoracic surgical interventions were performed through cervical incisions [4,5]. There is a trend in favor of using flexible endoscopy in general surgery [6]. Flexible endoscope is used in Natural Orifice Trans-luminal Endoscopic Surgery (NOTES) techniques [7]; and few cases were reported on its application in abdominal surgery. Latest attempts in minimizing surgical trauma lead to an experimental trans oral access to the mediastinal for lymph node biopsies. Human application has been described for NOTES in thoracic surgery [8], but ethical restraints and the risk of major mediastinal complications limit its application on humans. The aim of this experimental work on animal is to evaluate the use of flexible endoscope for the exploration of thoracic cavity and pleura through a single trans oral incision.

High-level endoscope disinfection processes in emerging economies: financial impact of manual process versus automated endoscope reprocessing

The use of flexible endoscopes is growing rapidly around the world. Dominant approaches to high-level disinfection among resource-constrained countries include fully manual cleaning and disinfection and the use of automated endoscope reprocessors (AERs). Suboptimal reprocessing at any step can potentially lead to contamination, with consequences to patients and healthcare systems. To compare the potential results of guideline-recommended AERs to manual disinfection along three dimensions - productivity, need for endoscope repair, and infection transmission risk in India, China, and Russia. Financial modelling using data from peer-reviewed published literature and country-specific market research. In countries where revenue can be gained through productivity improvements, conversion to automated reprocessing has a positive direct impact on financial performance, paying back the capital investment within 14 months in China and seven months in Russia. In India, AER-generated savings and revenue offset nearly all of the additional operating costs needed to support automated reprocessing. Among endoscopy facilities in India and China, current survey-reported practices in endoscope reprocessing using manual soaking may place patients at risk of exposure to pathogens leading to infections. Conversion from manual soak to use of AERs, as recommended by the World Gastroenterology Organization, may generate cost and revenue offsets that could produce direct financial gains for some endoscopy units in Russia and China.

Recent advances in diagnostic and therapeutic endoscopic ultrasound

Keywords:: bile duct obstructionselasticity imaging techniquesendoscopic ultrasonographyendoscopyfiducial markerfine-needle aspirationshumanKRAS proteinultrasonic

ECIRS (Endoscopic Combined IntraRenal Surgery) in the Galdakao-modified supine Valdivia position: a new life for percutaneous surgery?

Percutaneous nephrolithotomy (PNL) is still the gold-standard treatment for large and/or complex renal stones. Evolution in the endoscopic instrumentation and innovation in the surgical skills improved its success rate and reduced perioperative morbidity. ECIRS (Endoscopic Combined IntraRenal Surgery) is a new way of affording PNL in a modified supine position, approaching antero-retrogradely to the renal cavities, and exploiting the full array of endourologic equipment. ECIRS summarizes the main issues recently debated about PNL. The recent literature regarding supine PNL and ECIRS has been reviewed, namely about patient positioning, synergy between operators, procedures, instrumentation, accessories and diagnostic tools, step-by-step standardization along with versatility of the surgical sequence, minimization of radiation exposure, broadening to particular and/or complex patients, limitation of post-operative renal damage. Supine PNL and ECIRS are not superior to prone PNL in terms of urological results, but guarantee undeniable anesthesiological and management advantages for both patient and operators. In particular, ECIRS requires from the surgeon a permanent mental attitude to synergy, standardized surgical steps, versatility and adherence to the ongoing clinical requirements. ECIRS can be performed also in particular cases, irrespective to age or body habitus. The use of flexible endoscopes during ECIRS contributes to minimizing radiation exposure, hemorrhagic risk and post-PNL renal damage. ECIRS may be considered an evolution of the PNL procedure. Its proposal has the merit of having triggered the critical analysis of the various PNL steps and of patient positioning, and of having transformed the old static PNL into an updated approach.

Video-assisted pericardioscopic surgery: refinement of a new technique for implanting epimyocardial pacemaker leads☆☆☆

Current alternative approaches for pacemaker lead implantation imply the breach of the pleural space. Recently, the feasibility of experimental lead implantation by rigid endoscopy has been described. The use of flexible endoscopes and a standardised application has not been realised yet. Our main goal was to compare rigid and flexible endoscopy and to establish a standardised protocol for the implementation of a closed-chest subxiphoid approach for epimyocardial lead implantation. Rigid and flexible endoscopes were used for placement of screw-in pacing leads (4-F). A total of 17 adult pigs (80 kg) were anaesthetised and a 10-mm subxiphoid axial incision performed. The pericardium was opened and entered under endoscopic vision. Epimyocardial electrodes were implanted through the endoscope onto all four chambers. Standard haemodynamic measurements and pacing measurements were carried out. Both methods were deployed in the first three individuals. Superior endorsement of rigid endoscopy, due to better orientation and stability, led to its exclusive deployment in the remaining 14 individuals. Access to the implantation sites was quick (<10 min). A plastic cover had to be applied to reduce arrhythmia (VentricularExtraSystoles(bare): 17 ± 2.2 min(-1) vs VentricularExtraSystoles(cover): 5 ± 1.9 min(-1); n = 4). Measured pacing parameters were comparable with classic endocardial-derived thresholds. Post-mortem examination revealed no relevant damage/injury and/or bleeding in the heart and circumjacent tissue. There was no evidence of injury at the implantation sites and the corresponding pericardium. The electrodes showed excellent anchorage inside the myocardial tissue (penetration depths: 3 ± 0.2mm) and resisted high tractive forces. Flexible endoscopy is not suitable for exclusive deployment inside the pericardial space, whereas rigid endoscopy presented itself as a safe, fast and simple approach for epimyocardial lead implantation using an insulating trocar. Without cover, malignant arrhythmia constrains the implementation of video-assisted pericardioscopic surgery (VAPS). Subxiphoid VAPS permits optimal lead positioning under direct vision without fluoroscopy, without the breach of the pleural space and with a short procedural duration (<60 min). Our standardised minimal-invasive approach allows visualisation and intervention, potentially of all intrapericardial structures.

Use of flexible endoscopes for NOTES: sterilization or high-level disinfection?

Natural orifice translumenal endoscopic surgery (NOTES) involves the use of flexible endoscopes to perform intra-abdominal or intra-thoracic surgeries. Surgery in the operating room usually involves sterile instrumentation, whereas in the endoscopy suite high-level disinfection seems to be sufficient. Our objective was to assess the necessity for endoscope sterilization for clinical NOTES and to develop an endoscope processing protocol based on a score for the available processing options. Score and processing protocol development for clinical NOTES endoscopes was based on a comprehensive review of the available relevant literature. Options for sterilization for flexible endoscopes in the Good Samaritan Hospital, Legacy Health in Portland, Oregon, were analyzed for patient safety, potential for recontamination, cost, and validation. Literature survey indicated that there is controversy surrounding the necessity for sterilization of surgical endoscopes. However, standard of practice seems to call for sterile instrumentation for surgery and it is possible to terminally sterilize flexible endoscopes. Within our institution, a score was created to rank the available sterilization options. We successfully introduced a protocol for sterilization of endoscopes for use in clinical NOTES procedures. The protocol involved mechanical cleaning and high-level disinfection per Multi-Society Guidelines, with subsequent terminal sterilization using a validated peracetic acid protocol. It remains controversial whether sterile instrumentation is truly needed for surgery. It is difficult but possible to terminally sterilize flexible endoscopes. We recommend sterile instrumentation for clinical NOTES until well-designed, randomized, clinical trials are available and guidelines are published.

Automatic Adaptive Enhancement for Images Obtained With Fiberscopic Endoscopes

Modern techniques for medical diagnostics and therapy in keyhole surgery scenarios as well as technical inspection make use of flexible endoscopes. Their characteristic bendable image conductor consists of a very limited number of coated fibers, which leads to so-called comb structure. This effect has a negative impact on further image processing steps such as feature tracking because these overlaid image structures are wrongly detected as image features. With respect to these tasks, we propose an automatic approach to generate optimal spectral filter masks for enhancement of fiberscopic images. We apply the Nyquist-Shannon sampling theorem to the spectrum of fiberscopically acquired images to obtain parameters for optimal filter mask calculation. This can be done automatically and independently of scale and resolution of the image conductor as well as type and resolution of the image sensor. We designed and verified simple rotation invariant masks as well as star-shaped rotation variant masks that contain information about orientation between the fiberscope and sensor. A subjective survey among experts between different modes of filtering certified the best results to the adapted star-shaped mask for high-quality glass fiberscopes. We furthermore define an objective metric to evaluate the results of different filter approaches, which verifies the results of the subjective survey. The proposed approach enables the automated reduction of fiberscopic comb structure. It is adaptive to arbitrary endoscope and sensor combinations. The results give the prospect of a large field of possible applications to reduce fiberscopic structure both for visual optimization in clinical environments and for further digital imaging tasks.

Treatment of Zenker's diverticulum

Although Ludlow1 in 1769 gave the first description of a pharyngo-esophageal diverticulum, it is named after Zenker who gave a precise pathologic description more than one century later2. Zenker’s diverticulum (ZD) is the commonest type of diverticulum in the upper gastro-esophageal tract. It is a herniation which usually arises in the posterior midline of the hypopharynx at a place where the muscular wall has weakened. The ZD is usually located just cranial to the upper esophageal sphincter (UES) of which the cricopharyngeal muscle is a part. However, a ZD can develop at any weak site of the muscular wall of the hypopharynx. Increased hypopharyngeal pressures during swallowing are probably important in the pathogenesis of the diverticulum3 4. The tissue bridge between the esophageal lumen and the pouch of the diverticulum is composed of mucosa, submucosa and fibrous tissue of varying thickness, and a muscular coat. In this tissue bridge the most voluminous and essential structure is the UES.

Complete removal of colloid cyst via CT-guided stereotactic biportal neuroendoscopy.

Four patients harbouring a colloid cyst of the 3rd ventricle were operated on endoscopically. With the "classical" monoportal technique, through a precoronal burr hole only partial removal could be achieved in the first case. As the crucial point of the procedure is the safe dissection of the cyst from the thela chorioidea and from the internal cerebral veins, adequate control of the posterior rim of the foramen of Monro and the roof of the 3rd ventricle is mandatory. Accordingly in other three cases a CT-guided biportal endoscopic technique was applied, which permitted radical removal of the entire cyst with maximum safety. CT-guidance is essential for optimal planning after careful study of the individual anatomy. In this way the rigid scopes are moved exclusively along their own axes throughout the procedure, the resulting brain damage thereby being minimal. With regard to all circumstances of the procedure, the use of flexible endoscopes appears to be inappropriate and biportal endoscopy offers itself as the method of choice.

Endoscopic neurosurgery "around the corner" with a rigid endoscope. Technical note.

Endoscopically "working around the corner" is presently restricted to the use of flexible endoscopes or an endoscope-assisted microneurosurgical (EAM) technique. In order to overcome the limitations of these solutions, endoscopic equipment and techniques were developed for "working around the corner" with rigid endoscopes. A steering insert with a 5 French working channel is capable of steering instruments around the corner by actively bending the guiding track and consecutively the instrument. A special fixation device enables strict axial rotation of the endoscope in the operating field. Endoscopic procedures "around the corner", including aqueductal stenting, pellucidotomy, third ventriculostomy and biopsy were performed in human cadavers. Special features of the used pediatric neuroendoscope system, i.e., reliable fixation, axial rotation, and controlled steering of instruments, increase the safety and reduce the surgical traumatization in selected cases, such as obstructive hydrocephalus due to a mass lesion in the posterior third ventricle, since endoscopic third ventriculostomy and biopsy can be performed through the same burr hole trephination. Limitations of this technique are given by the size of the foramen of Monro and the height of the third ventricle as well as by the bending angle of the instruments (40-50 degrees).

Variceal injection sclerotherapy

With the development and widespread use of flexible endoscopes, injection sclerotherapy of oesophageal varices has advanced beyond the early stages. Althought slightly different techniques and different sclerosants are used, the results are not strikingly different. The cumulative rate of adverse effects is in the range of 20% to 40%, with a procedure-related mortility of around 1 to 2%. Sclerotherapy is the best available treatment for haemostosis of acute oesophageal variceal bleeding. However, as a long-term therapy it is less effective in the prevention of recurrent gastrointestinal bleeding events, since obliteration of all varices often takes several months. Furthermore, extra-oesophageal bleeding is not amenable to sclerotherapy. Thus, if repeated injections fail to prevent recurrent bleeding, other options such as shunt surgery, transection, chronic medical portal decompression with β-blockers or even of the individual patient. Prophylaxis of first variceal haemorrhage was benificial in selected patients with a high bleeding risk. It cannot, however, be generally recommended at present.