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At least 1,495 records · Page 83Linked to original sources
PubMed2002

Totally endoscopic coronary artery bypass grafting on cardiopulmonary bypass with robotically enhanced telemanipulation: report of forty-five cases.

BACKGROUND: Robotically enhanced telemanipulation is a new powerful tool for minimally invasive procedures that allows totally endoscopic cardiac surgery. Between June 1999 and February 2001, 45 robotically enhanced totally endoscopic coronary artery bypass grafting procedures on the arrested heart were performed at our institution with the use of the da Vinci telemanipulation system (Intuitive Surgical, Inc, Mountain View, Calif). METHODS: In 37 patients a single-vessel totally endoscopic coronary bypass operation was performed. Eight patients had different types of multivessel revascularization with both internal thoracic arteries. The initial conversion rate was 22% and dropped to 5% in the last 20 patients. Two patients required reexploration via median sternotomy. The first 22 patients had excellent graft patency on discharge. The procedural time for single-vessel totally endoscopic bypass was 4.2 +/- 0.4 hours, bypass time was 136 +/- 11 minutes, and aortic crossclamp time amounted to 61 +/- 5 minutes. CONCLUSION: The present data show the feasibility of closed chest single- and double-vessel revascularization, with good clinical results. However, procedural time is prolonged and the complex endoscopic and endoaortic occlusion techniques, as well as the extensive anesthesiologic monitoring, are demanding. The need for conversion to an open procedure diminished after a relatively short learning curve. All postulated benefits of totally endoscopic surgery other than excellent cosmesis must be evaluated in larger cohorts.

Aged↗
PubMed1987

Endoscopic laser resection of atherosclerotic plaque in a live animal model. A preliminary report on some technical difficulties.

This study was designed to determine whether laser energy could be used effectively to resect atherosclerotic plaque through an endoscope in a live animal model. Twelve adult Yorkshire swine with infrarenal aortic atherosclerosis had a 2.5 mm and/or 3.2 mm diameter fiberscope passed into the aorta from the femoral artery after proximal aortic balloon occlusion. Endoscopic argon laser resection of the atherosclerotic plaque was then attempted in eight pigs with an argon laser fiber (60 to 400 microns). We were able to visualize the raised atherosclerotic plaque in all 12 pigs with the larger 3.2 mm diameter fiberscope, which was easily passed into the aortoiliac system from the 4 mm diameter femoral vessel. The articulating end feature enhanced maneuverability within the lumen and allowed laser fiber direction. The 2.5 mm endoscope did not allow adequate visualization in any pig since the vessel could not be cleared of blood. The 2.5 mm endoscope was also passed from the femoral artery distally into the hind limb and still did not allow adequate visualization of the vessel wall because of persistent luminal blood. The 3.2 mm endoscope enabled vessel wall visualization distal to the femoral artery when the proximal artery was occluded. No aortas were grossly perforated by the laser energy. In all pigs undergoing endoscopic laser resection, raised plaques were removed both grossly and histologically, although the plaque edges were carbonized and frayed as well as vaporized. With the small spot size of the argon fiber, channels were drilled through plaque, frequently with incomplete recanalization of the lumen.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2001

The durability of endoscopic saphenous vein grafts: a 5-year observational study.

BACKGROUND: Endoscopic saphenous vein harvest has been explored as a minimally invasive alternative to a long continuous leg incision for removal of the greater saphenous vein. The endoscopic technique uses limited incisions (2-4) with extended "skin bridges" and videoscopic equipment for the dissection and removal of the greater saphenous vein. This study was undertaken to evaluate the long-term durability of saphenous vein grafts harvested by an endoscopic technique and used for lower extremity arterial revascularization. METHODS: All patients who underwent endoscopic saphenous vein harvesting for lower extremity arterial bypass grafting were prospectively followed for graft patency and risk factors. Grafts were surveyed with serial duplex scans at 3- to 6-month intervals over this 5-year study. Life-table methods were used to assess graft survival. A computerized registry and medical records were reviewed to determine graft patency and patient survival. RESULTS: From September 1994 to August 2000, 164 lower extremity arterial saphenous vein grafts harvested by an endoscopic technique were used for lower extremity arterial bypass grafting in 150 patients. The patient population included 111 males (75%) and 112 smokers (75%), but also included a high-risk cohort of 65 diabetic patients (43%) and 15 patients undergoing dialysis/renal transplant (10%). Twenty-eight patients (19%) died within the study period. With life-table methods, 1-, 3-, and 5-year secondary patency rates were 85% (+/- 3.2%), 74% (+/- 5.7%), and 68% (+/- 11.6%). Of the 30 failed grafts, 7 (4%) failed in the first month related to inadequate runoff (4), cardiac instability (2), and an additional surgical procedure (1). Twenty-three grafts (14%) failed between 1 and 42 months. Twenty-two (16%) of these 134 patent grafts underwent a second procedure to maintain patency (13 as primary-assisted patency and 9 as secondary patency). CONCLUSIONS: Endoscopic saphenous vein harvest for lower extremity arterial reconstruction provides a satisfactory conduit for lower extremity bypass grafting. Although increased manipulation from this limited access technique may incite an injury response in the vein, these vein grafts can maintain an adequate patency for lower extremity bypass grafting.

Adult↗
PubMed2002

Usefulness of virtual endoscopic three-dimensional reconstructions of the middle ear.

This work uses a new programme for producing 3D radiological images acquired by means of CT which enables the internal surfaces of the examined structures to be visualized. This new method, which is able to navigate inside organs in a similar way to fibreoptic endoscopy, is known as virtual endoscopy. CT examinations of the temporal bone were carried out using spiral equipment and endoscopic 3D processing was carried out on a separate workstation equipped with a volume-rendering programme. Once the technical parameters necessary for obtaining a representation of the internal surfaces had been defined, a simulation of a virtual otoscopy was conducted by moving the virtual endoscope from the external auditory canal through the annulus to the tympanic cavity. The simulation can be obtained either by moving the endoscope by hand, using the mouse, or by defining a path along which the software automatically creates an endoscopic 3D reconstruction. The images thus obtained are projected sequentially to give a "movie" effect, i.e. a continuous progression of the endoscope. The average time required to conduct the procedure ranges from 20 to 30 min. A virtual endoscopic visualization of the middle ear was obtained which, in particular, generated images of the tympanic cavity with the ossicular chain. In our experience, virtual otoscopy shows the anatomy of the structures of the tympanic cavity in excellent detail and may be considered complementary to CT, providing useful images enabling better visual representation and understanding of this complex structure. Although clinical applications of the technique remain to be defined it may have a role to play in presurgical diagnostic evaluation of the ossicular chain, epitympanum and retrotympanum.

Ear, Middle↗
PubMed1998

Third ventriculostomy, phase-contrast cine MRI and endoscopic techniques.

Endoscopic third ventriculostomy has become an increasingly popular procedure. This is mainly due to the improvement of the endoscopes. The progress in imaging techniques and Phase-Contrast Cine MRI in particular offers a reliable method of pre-and post-operative assessment of the patients. Two endoscopes, NeuroPEN and Channel Neuroendoscope (Medtronic PS Medical, CA, USA) have been evaluated in our center for third ventriculostomy. These instruments are light, have a good maneuverability and are disposable. The illumination and the quality of the image are excellent. We have performed Phase-Contrast Cine MRI pre-operatively and post-operatively for our patients. It offers a good assessment of the patency of the ventriculostomy and the fluid dynamics of the CSF pathways. Endoscopic third ventriculostomy is the technique of choice for the treatment of obstructive hydrocephalus. This is mainly due to two points: The progress in the endoscopic instrumentation (namely the reduction in size of endoscopes and introduction of disposable models), and the establishment of Phase-Contrast Cine MRI as the gold standard method for the pre- and post-operative evaluation of the CSF dynamics. However, to date, no technique can show the patency of the subarachnoid space, which is the most important predictive factor of surgical outcome.

Endoscopy↗
PubMed1999

Advances in digital imaging during endoscopic surgery.

BACKGROUND AND OBJECTIVE: Digital imaging capabilities have recently been incorporated into a number of video systems. Contrast enhancement when using a rigid or semirigid endoscope improves image definition by seeking out existing transitions in detail. Only the areas of transition are accentuated, whereas areas without detail are unaffected. During flexible endoscopy, fiberoptic bundles create a classic honeycomb appearance. The use of "fiberscope" filters minimizes this appearance by expanding the image of each fiberoptic fiber. We therefore assessed whether new developments in digital video image processing have improved image quality for endoscopic surgery. MATERIALS AND METHODS: Fifty urologists reviewed a video playback of various endourologic procedures. The type of endoscope was identified, but the urologic surgeon was blinded to the level of enhancement (high or low) or fiberscope filter (A or B) used. Each video clip was scored from 1 to 5 for the following image variables: identification of structure, detail of image, and background noise or interference. All results were averaged and compared using Student's paired t-test. RESULTS: During rigid endoscopy, the high and low digital enhancement settings were both superior to no enhancement (P < 0.001), and high enhancement was better than low (P < 0.001). With semirigid endoscopic procedures, high and low digital enhancement were comparable but were superior to no enhancement (P < 0.001). Filters A and B were no better than no enhancement. There was a significant improvement noted with the use of filter A or B during flexible ureteroscopy over no enhancement (P < 0.001). In addition, filter A was better than filter B (P < 0.001). CONCLUSIONS: Digital enhancement settings during video endoscopy significantly improve images from rigid and semirigid endoscopes. The digital fiberscope filter significantly improves images obtained during flexible ureteroscopy. Digital image enhancement capabilities should be strongly considered when upgrading video systems. Digital technology must be further studied to improve clinical video imaging during endoscopic surgery.

Endoscopy↗
PubMed2005

Usefulness and limitation of multiple endoscopic biopsy sampling for epidermal growth factor receptor and c-erbB-2 testing in patients with gastric adenocarcinoma.

BACKGROUND: Our objective was to examine the utility of endoscopic biopsy specimens in judging the status of epidermal growth factor receptor (EGFR) and c-erbB-2 genes and proteins in the entire tumor. METHODS: Endoscopic biopsy specimens and specimens of whole representative cut surfaces of corresponding surgically resected tumors were obtained from 14 patients with gastric carcinoma, and immunohistochemistry and fluorescence in situ hybridization were then performed to determine the protein expression and gene amplification profiles, respectively, of EGFR and c-erbB-2 in these biopsy and surgical specimens. RESULTS: Among the eight endoscopic biopsy specimens obtained from three gastric carcinomas in which EGFR protein overexpression and gene amplification were judged to be positive in the corresponding surgically resected tissue specimens, EGFR overexpression was detected in three specimens (38%), but EGFR amplification was not detected (0%). Among the 19 endoscopic biopsy specimens obtained from five gastric carcinomas in which c-erbB-2 protein overexpression and gene amplification were judged to be positive in the corresponding surgically resected tissue specimens, c-erbB-2 overexpression and amplification (c-erbB-2/CEP17 ratio) were detected in 14 (74%) and 16 (84%) specimens, respectively. All three cases with EGFR overexpression and all five cases with c-erbB-2 overexpression showed intratumor heterogeneity with regard to their EGFR and c-erbB-2 status, respectively. CONCLUSIONS: The c-erbB-2 status could be adequately assessed not only by examining surgically resected materials, but also by examining multiple endoscopic biopsy specimens. On the other hand, to assess the EGFR status accurately, the use of surgically resected samples appeared to be more reliable than the use of multiple endoscopic biopsy samples.

Adenocarcinoma↗
PubMed2001

Endoscopic suturing and knot tying: theory into practice.

OBJECTIVE: To advance modern surgical techniques of endoscopic knot tying, encompassing a new appreciation of knot-tying theory and the application of second-generation, purpose-designed instruments. SUMMARY BACKGROUND DATA: During open surgery, surgeons automatically create the surgical half-hitch by using either instrument or hand/finger knot-tying methods (figure 4). Each of these methods, which are mirror images of each other, forms the same result, the half-hitch. Two opposing half-hitches are needed to form a square knot. There are many ways for new-generation instruments to create a secure square knot during endoscopic surgery. An overview of the current endoscopic knot-tying methods is presented. METHODS: The author presents a theoretical analysis of square knot-tying techniques as applied during instrument and hand/finger movements. The application of a mirror-image concept was considered in the analysis of these two contrasting methods. RESULTS: There are 12 ways to create a square knot, some of which have previously not been described or needed in open surgery. Some of these methods have particular application in endoscopic surgery. CONCLUSIONS: A new understanding of knot-tying theory has been developed, with innovative methods being defined for tissue approximation during endoscopic surgery. These ergonomic, efficient, and contrasting methods of knot tying are described using second-generation endoscopic instruments. The new techniques have direct and broad application in many fields of minimally invasive surgery.

Endoscopy↗
PubMed2002

Endoscopic treatment of lower gastrointestinal bleeding.

Urgent colonoscopy has emerged as the initial diagnostic and main therapeutic tool in the evaluation and treatment of colonic lower gastrointestinal bleeding. Endoscopic therapy can effectively treat most cases of colonic bleeding with a demonstrable improvement in clinical outcome parameters. The identification of high-risk stigmata of hemorrhage enables selective targeting of endoscopic therapy to lesions at high risk of rebleeding. Advances in technologies such as novel mechanical methods of hemostasis (eg, metallic clips), injection techniques (eg, cyanoacrylate injection), and the widening application of established endoscopic hemostatic techniques (eg, rubber-band ligation) to colonic lesions offers the possibility of further improvements in the efficacy of endoscopic hemostasis. Clinical trials are needed to compare these novel endoscopic techniques with more conventional approaches to establish the best form of endoscopic therapy for different bleeding lesions and finally to establish more definitively the optimal timing of colonoscopy.

Journal Article↗
PubMed2002

Endoscopic ultrasound of the pancreas: tissue acquisition and intervention.

Endoscopic ultrasound is an established modality for staging gastrointestinal and pancreatic malignancies. Since the development of the linear array echoendoscope, the field of interventional endoscopy has continued to evolve as an adjunctive method to standard endosonography. The ability to sample extraluminal lesions or lymph nodes has overcome the initial limitations of endoscopic ultrasound and provided a list of attractive endoscopic ultrasound-guided therapeutic applications.This review focuses on recent advancements in the field of interventional endosonography related to the diagnosis and therapy of pancreatic diseases. In particular, the article reviews the role of endoscopic ultrasound-guided fine-needle aspiration in diagnosing various pancreatic diseases; the role of endoscopic ultrasound-guided fine-needle injection in delivering neurolytic, chemotherapeutic, or biologic agents; and emerging procedures like endoscopic ultrasound-assisted biliary bypass in the setting of malignant biliary obstruction.

Journal Article↗
PubMed2003

Role of endoscopic ultrasonography in the staging of esophageal cancer: a review.

PURPOSE OF REVIEW: This review summarizes the important studies, published since April 2002, on the role of endoscopic ultrasonography for staging of esophageal cancer. RECENT FINDINGS: The loco-regional staging accuracy for esophageal cancer by endoscopic ultrasonography is superior to other currently available imaging modalities such as helical computed tomography. Endoscopic ultrasonographic staging accuracy is further enhanced by the ability to obtain guided fine needle aspiration specimens for cytology from any suspicious celiac lymph nodes. In addition to the initial staging of esophageal cancer, endoscopic ultrasonography-based measurement of reduction of tumor cross-sectional area appears to be a reliable predictor of pathologic response to initial neoadjuvant therapy. Recently published studies on the outcomes of endoscopic ultrasonography support its utility in the staging of esophageal cancer, particularly in guiding different treatment options for different stages of loco-regional involvement. SUMMARY: Overall, endoscopic ultrasonography for staging of patients with esophageal cancer seems to be a cost-effective intervention.

Journal Article↗
PubMedDate not supplied

Flexible endoscopes: structure and function. The suction and biopsy channel.

Flexible endoscopes are complex medical instruments that are easily damaged. To maintain the flexible endoscope in optimum working condition, the user must have a thorough understanding of the structure and function of the instrument. This is the second in a series of articles presenting an in-depth look at the care and handling of the flexible endoscope. The first article discussed the air and water system. This article will focus specifically on the suction and biopsy channel system. The flexible endoscope is constructed of several systems that operate simultaneously to produce a highly technical, yet effective diagnostic and therapeutic medical device. These systems include the air and water system, the suction or operating channel system, the mechanical system, the endoscopic retrograde cholangiopancreatography (ERCP) elevator system, the optical system, and the electrical system. A review of the internal and external structure of the flexible endoscope and the functions of the channel system, including infection control issues, potential problems and evaluation, and prevention of minor problems to avoid expensive repairs, will be addressed.

Biopsy↗
PubMed1997

Endoscopically assisted plastic surgical procedures in the pediatric patient.

Endoscopically assisted surgery has gained wide popularity in plastic surgery. Its major uses have been in aesthetic procedures. In this article we demonstrate the safety and utility of these techniques to a pediatric population. All patients younger than 20 years who underwent an endoscopically assisted plastic surgical procedure by one of the authors were pooled and their medical records reviewed. Complications were determined. For those children having an excision of a forehead mass, the duration of the procedure, length of incision, specimen size, and length of hospital stay were determined. Additionally, parents of these children were contacted by telephone after the excisions to determine satisfaction with the procedures. Sixteen patients' records were reviewed. Patients' ages ranged from 6 months to 15 years (mean, 5.8 years). The procedures performed included removal of forehead mass (n = 9), placement of tissue expanders (n = 5), excision of gynecomastia (n = 1), and malar soft tissue elevation (n = 1). All procedures were completed with endoscopic assistance. One procedure had to be converted to an open technique. No hematomas were observed. For forehead mass excisions, the average duration of the procedure was 46.9 min. Incision length was 1.1 cm, and specimen volume was 0.5 cm3. Parent satisfaction with the endoscopic procedures was high, with 100% responding favorably. No significant complications were observed. Many of the procedures were performed as outpatients. Parental acceptance of and satisfaction with the endoscopic techniques was high. Our experience supports the use of endoscopic techniques in the pediatric plastic surgical patient.

Adolescent↗
PubMed1992

The clinical and endoscopic spectrum of the watermelon stomach.

The watermelon stomach is an uncommon but treatable cause of chronic gastrointestinal bleeding. We report our experience with the clinical and endoscopic features of 45 consecutive patients treated by endoscopic Nd:YAG laser coagulation. The prototypic patient was a woman (71%) with an average age of 73 years (range of 53-89 years) who presented with occult (89%) transfusion-dependent (62%) gastrointestinal bleeding over a median period of 2 years (range of 1 month to > 20 years). Autoimmune connective tissue disorders were present in 28 patients (62%), especially Raynaud's phenomena (31%) and sclerodactyly (20%). Atrophic gastritis occurred in 19 of 19 (100%) patients, with hypergastrinemia in 25 (76%) of 33 patients tested. Antral endoscopic appearances included raised or flat stripes of ectatic vascular tissue (89%) or diffusely scattered lesions (11%). Proximal gastric involvement was present in 12 patients (27%), typically in the presence of a diaphragmatic hernia. Endoscopic laser therapy after a median of one treatment (range of 1-4) resulted in complete resolution of visible disease in four patients (13%) and resolution of > 90% in 24 patients (80%). Hemoglobin levels normalized in 87% of patients over a median follow-up period of 2 years (range of 1 month to 6 years) with no major complications. Blood transfusions were not necessary after laser therapy in 86% of 28 initially transfusion-dependent patients. The characteristic clinical, laboratory, and endoscopic features allow for a confident diagnosis that can lead to successful endoscopic treatment.

Aged↗
PubMed1995

The endoscopic appearance of severe intestinal Mycobacterium avium complex infection as a coarsely granular mucosa due to massive infiltration and expansion of intestinal villi without mucosal exudation.

Although Mycobacterium avium complex (MAC) is the most common opportunistic pathogen at postmortem in patients with AIDS, many cases are not recognized premortem. A patient with advanced AIDS had diarrhea, fecal occult blood, and iron deficiency anemia. Esophagogastroduodenoscopy showed an extensive coarsely granular mucosa, resistant to endoscopic irrigation and brushing, in the descending duodenum. Histologic analysis of duodenal biopsies confirmed expansion of intestinal villi due to massive villar infiltration by acid-fast bacilli and no mucosal exudation. An absence of mucosal exudation is consistent with an attenuated local immunologic response in advanced AIDS. MAC was isolated from mycobacterial culture of duodenal biopsies. The currently reported endoscopic appearance of intestinal MAC can aid in diagnosis by alerting the endoscopist to send biopsies for mycobacterial stains and cultures when MAC infection is suggested by this endoscopic appearance. However, even in the absence of endoscopically evident lesions, gastrointestinal endoscopic biopsy is appropriate to exclude occult opportunistic pathogens in an AIDS patient with wasting or significant gastrointestinal complaints. The currently reported pathologic findings show that villar engorgement and hypertrophy is a sufficient explanation for the granular endoscopic appearance of intestinal MAC and that mucosal exudation is not required to produce this appearance.

AIDS-Related Opportunistic Infections↗
PubMed1999

Standardization in endoscopic reporting: implications for clinical practice and research.

The large number of endoscopies and endoscopic reports produced in the United States represents a large repository of clinical data. However, reports are highly variable in content and structure and therefore cannot be used to create clinical databases. The introduction of automated endoscopic reporting systems should permit database creation only if acceptable standards for the structure and content of the report are developed. The structure of an endoscopic report is the framework in which the specific details of the endoscopy can be recorded. The basic components can consist of the following: Patient, Visit, Study, Result, Diagnosis, and Recommendation. Precise definition of each of these components requires consensus on what the minimum included elements should be. Experience with the Minimal Standard Terminology indicates that it is possible to create a broadly acceptable lexicon of descriptive endoscopic terms which can be included as a Result. The systematic development of the structure and content of endoscopic reports is mandatory before it is possible to create large, clinically useful databases of endoscopic reports.

Databases, Factual↗
PubMed2002

A prospective study of endoscopic esophageal variceal ligation using a multiband ligator.

BACKGROUND: Endoscopic variceal band ligation (EVL) is the preferred method of treating variceal hemorrhage in adults. The need to reinsert the endoscope after reloading for each varix ligation has been a drawback. The Saeed multiband ligator allows ligation of multiple varices during a single insertion. The multibander has not been used previously in children. METHODS: Twenty-eight consecutive children were referred to a pediatric liver unit because of esophageal variceal bleeding from 1998 to 2000. Endoscopic variceal band ligation was performed at initial endoscopy and repeated monthly until varices were obliterated or were too small to ligate. RESULTS: Results are expressed as median (range). Age at EVL was 11 years (3 months to 16 years) and weight 30 kg (5.4-63 kg). Portal hypertension was caused by cirrhosis in 15 children. Endoscopic variceal band ligation was performed on 66 occasions with 4 bands applied per session. Ten children had active bleeding at initial endoscopy and all responded to EVL. Interval bleeding developed in 2 children before variceal ablation. Varices were obliterated in 26 of 28 patients after 2 sessions. During the 21-month follow-up (2 months to 3 years), six children have undergone elective liver transplantation and three have had mesoportal bypass procedures. Rebleeding developed in 2 of 26; 1 from recurrent esophageal varices that responded to repeat EVL and 1 from gastric varices. Following variceal ablation, 2-year actuarial variceal recurrence risk was 40%. CONCLUSIONS: Endoscopic variceal ligation is highly effective in obliterating esophageal varices in children. The use of a multibander device for endoscopic variceal ligation is technically feasible and safe even in small children, and its use results in more rapid ablation of esophageal varices.

Adolescent↗
PubMed1999

Evaluation of surgical approaches to endoscopic auditory brainstem implantation.

OBJECTIVES: This study investigates the use of endoscopy for the placement of an auditory brainstem implant by translabyrinthine, retrosigmoid (suboccipital), and middle cranial fossa approaches. STUDY DESIGN: Cadaver dissection and endoscope-assisted placement of the auditory brainstem implant. METHODS: Translabyrinthine, retrosigmoid, and middle cranial fossa dissections were performed bilaterally in five cadaveric heads. An auditory brainstem implant was placed within the lateral recess of the fourth ventricle under endoscopic visualization. The implantation was performed with all approaches and documented by digital image capture followed by production of dye-sublimation photographic prints. RESULTS: The lateral recess was visualized with the endoscope in all three approaches to the brainstem. The 30 degrees endoscope provided the best visualization by translabyrinthine and retrosigmoid dissection and was essential for the middle cranial fossa approach. Refinement of implant position was readily achieved, as even the deepest portion of the recess could be seen with all three approaches. CONCLUSIONS: This study finds that endoscopy provides superior visualization of the lateral recess of the fourth ventricle than the operating microscope with all approaches. The retrosigmoid approach is recommended, as it provides the best view of the implantation site and the easiest angle for placement of the prosthesis. The use of the endoscope may allow for a smaller craniotomy than with conventional microscopic techniques, depending on tumor size. The translabyrinthine approach provides a good view of the lateral recess but had no advantage over other approaches. The middle cranial fossa approach is only possible with angled endoscopes; however, it is technically the most difficult and places the facial nerve at greatest risk.

Acoustic Stimulation↗