Improving Voice Outcomes After Thyroid Surgery - Review of Safety Parameters for Using Energy-Based Devices Near the Recurrent Laryngeal Nerve

Technological advances in thyroid surgery have rapidly increased in recent decades. Specifically, recently developed energy-based devices (EBDs) enable simultaneous dissection and sealing tissue. EBDs have many advantages in thyroid surgery, such as reduced blood loss, lower rate of post-operative hypocalcemia, and shorter operation time. However, the rate of recurrent laryngeal nerve (RLN) injury during EBD use has shown statistically inconsistent. EBDs generate high temperature that can cause iatrogenic thermal injury to the RLN by direct or indirect thermal spread. This article reviews relevant medical literatures of conventional electrocauteries and different mechanisms of current EBDs, and compares two safety parameters: safe distance and cooling time. In general, conventional electrocautery generates higher temperature and wider thermal spread range, but when applying EBDs near the RLN adequate activation distance and cooling time are still required to avoid inadvertent thermal injury. To improve voice outcomes in the quality-of-life era, surgeons should observe safety parameters and follow the standard procedures when using EBDs near the RLN in thyroid surgery.

One more option in heart failure: correction of mitral regurgitation with MitraClip®

Degenerative mitral regurgitation in elderly patients and functional mitral regurgitation secondary to severe left ventricular dysfunction are not easy options for conventional surgery. Recently, a new percutaneous approach has been proposed with the MitraClip^®, based on the Alfieri edge-to-edge repair technique. The aim of the study is to report, compare and discuss the results of two multicenter randomized trials: MITRA.FR and COAPT in light of the current practice. In both trials patients with functional mitral regurgitation grade 3/4+ or 4/4+ were randomly assigned, in 1:1 ratio, to undergo percutaneous repair and optimal medical therapy or optimal medical therapy alone. Other baseline characteristics reflecting severity of mitral regurgitation and of left ventricular impairment were statistically different, such as the effective regurgitant orifice area (0.31 cm² in MITRA.FR vs 0.41 cm² in COAPT) and the indexed LVEDV (135 ± 37 ml/m² in MITRA.FR vs 101 ± 34 ml/m² in COAPT). A 24 months follow-up and a 12 months follow-up have been completed, respectively, in COAPT and MITRA.FR. Out of the 307 patients enrolled in the MITRA.FR, 152 were randomized to percutaneous treatment but only in 138 (95.8%) the MitraClip^® was actually implanted. At the end of the follow-up a residual mitral regurgitation of at least grade 3+ has been observed in 17% of the patients. A composite of death from any cause or unplanned hospitalizations for heart failure at 12 months respectively occurred in 83 patients (54.6%) treated percutaneously and 78 patients (51.3%) treated with medical therapy only. A total of 614 patients have been enrolled in the COAPT and 293 underwent transcatheter treatment. A successful implantation of the MitraClip^® was achieved in 287 patients (98.0%). Hospitalization for heart failure at 24 months occurred in 160 patients in the device group and in 283 in the control group, with an annualized ratio of 35.8% and 67.9%, respectively (p > 0.001). The conflicting results of the two trials may have many explanations, but probably the main cause is the most stringent inclusion criteria in COAPT. The effective reduction of mitral regurgitation and improvement in exercise capacity already observed in registries including more than 70,000 patients was confirmed in a randomized trial with improvement observed in hard end-points. This has already led to an extension of FDA approval to functional regurgitation and a more liberal use across the world.

Endoscope Holders in Cranial Neurosurgery: Part 2-An International Survey

BACKGROUND

Following a previous systematic review of currently available endoscope holders (EHs), we aspired to detect trends, task-specific preferences, and pitfalls of EH in various cranial neuroendoscopic procedures.

METHODS

A questionnaire was disseminated to members of the International Federation of Neuroendoscopy. The questionnaire evaluated indications and pitfalls of EH in different applications, in particular, differentiating between intraventricular and skull base endoscopy, as well as subcategories of these 2 main fields. Furthermore, interest or involvement in research projects on EH was investigated.

RESULTS

Fifty-two surgeons responded, with a broad geographic distribution represented. Most (54%) do not routinely use EH. Others use holders mainly for intraventricular rather than skull base procedures. Most surgeons (96%) regularly work with a co-surgeon. Reported weaknesses of EH included crude movements, downward drift, loss of depth perception, lack of flexibility, iatrogenic injury, cost, and bulky construct. There is still a lack of consensus on surgical indications. Tumor resections in intraventricular and skull base regions (not small sellar tumors) seem to stand out as good, widely accepted indications.

CONCLUSIONS

Although EH have a role in cranial neuroendoscopy, their use seems limited and their technical features are regarded as suboptimal by most neuroendoscopists. Weaknesses and implications were detected in all application categories (skull base and intraventricular) but may vary slightly. Potentially, separate systems with distinct features may be required for skull base versus intraventricular surgery. There is a need for further evolution of EH, which could lead to a future paradigm shift in their use.

[Clinical epidemiological characteristics and change trend of upper gastrointestinal bleeding over the past 15 years]

OBJECTIVE

To investigate the clinical epidemiology change trend of upper gastrointestinal bleeding (UGIB) over the past 15 years.

METHODS

Consecutive patients who was diagnosed as continuous UGIB in the endoscopy center of The First Affiliated Hospital of Sun-Yat University during the period from 1 January 1997 to 31 December 1998 and the period from 1 January 2012 to 31 December 2013 were enrolled in this study. Their gender, age, etiology, ulcer classification, endoscopic treatment and hospitalization mortality were compared between two periods.

RESULTS

In periods from 1997 to 1998 and 2012 to 2013, the detection rate of UGIB was 9.99%(928/9 287) and 4.49%(1 092/24 318)(χ²=360.089, P=0.000); the percentage of male patients was 73.28%(680/928) and 72.44% (791/1 092) (χ²=0.179, P=0.672), and the onset age was (47.3±16.4) years and (51.4±18.2) years (t=9.214, P=0.002) respectively. From 1997 to 1998, the first etiology of UGIB was peptic ulcer bleeding, accounting for 65.2%(605/928)[duodenal ulcer 47.8%(444/928), gastric ulcer 8.3%(77/928), stomal ulcer 2.3%(21/928), compound ulcer 6.8%(63/928)],the second was cancer bleeding(7.0%,65/928), and the third was esophageal and gastric varices bleeding (6.4%,59/928). From 2012 to 2013, peptic ulcer still was the first cause of UGIB, but the ratio obviously decreased to 52.7%(575/1092)(χ²=32.467, P=0.000)[duodenal ulcer 31.9%(348/1092), gastric ulcer 9.4%(103/1092), stomal ulcer 2.8%(30/1092), compound ulcer 8.6%(94/1092)]. The decreased ratio of duodenal ulcer bleeding was the main reason (χ²=53.724, P=0.000). Esophageal and gastric varices bleeding became the second cause (15.1%,165/1 092, χ²=38.976, P=0.000), and cancer was the third cause (9.2%,101/1 092, χ²=3.352, P=0.067). The largest increasing amplitude of the onset age was peptic ulcer bleeding [(46.2±16.7) years vs. (51.9±18.9) years, t=-5.548, P=0.000), and the greatest contribution to the amplitude was duodenal ulcer bleeding [(43.4±15.9) years vs. (48.4±19.4) years, t=-3.935, P=0.000], while the onset age of esophageal and gastric varices bleeding [(49.8±14.1) years vs. (48.8±13.9) years, t=0.458, P=0.648] and cancer [(58.4±13.4) years vs. (58.9±16.7) years, t=-0.196, P=0.845] did not change significantly. Compared with the period from 1997 to 1998, the detection rate of high risk peptic ulcer rebleeding (Forrest stage I(a, I(b, II(a and II(b) increased (χ²=39.958, P=0.000) in the period from 2012 to 2013. From 1997 to 1998, 54 patients underwent endoscopic treatment, and the achievement ratio of hemostasis was 79.6% (43/54). From 2012 to 2013, 261 patients underwent endoscopic treatment and the achievement ratio of hemostasis was 96.9%(253/261), which was significantly higher (χ²=23.287, P=0.000). Compared to the period from 1997 to 1998, more patients with variceal bleeding or non-variceal bleeding received endoscopic treatment in time (39.0% vs. 70.3%, χ²=51.930, P=0.000; 3.6% vs. 15.6%, χ²=62.292, P=0.000, respectively), and higher ratio of patients staging Forrest stage I(a to II(b also received endoscopic treatment in the period from 2012 to 2013 [27.4%(26/95) vs. 68.5%(111/162), χ²=40.739, P=0.000]. More qualified endoscopic hemostatic techniques were used, containing thermocoagulation (0 vs. 15.2%, χ²=79.518, P=0.000), hemostatic clip (0 vs. 55.9%, χ²=20.879, P=0.000), hemostatic clip combined with thermocoagulation (4.3% vs. 16.4%, χ²=5.154, P=0.023), while less single injection was used (87.1% vs. 6.2%, χ²=10.420, P=0.001), and single spraying for hemostasis was completely abandoned in the period from 2012 to 2013. The ratio of inpatients undergoing reoperation decreased obviously in the period from 2012 to 2013 [9.3%(86/928) vs. 6.0%(65/1092), χ²=7.970, P=0.005], while no significant difference was found in mortality during hospitalization between two periods.

CONCLUSION

Compared with the period from 1997 to1998, the mean onset age of UGIB increased, and the ratio of peptic ulcer bleeding decreased due to the reduction of duodenal ulcer bleeding, the detection rate of high risk peptic ulcer rebleeding increased, the cure rate of endoscopic treatment for UGIB increased, more reasonable and immediate hemostatic methods were used, but overall mortality did not change obviously in the period from 2012 to 2013.

[Characteristics of customized device for video-assisted thoracoscopic surgery]

Video-assisted thoracoscopic surgery (VATS) has been a mainstay in surgical interventions for an early staged lung cancer over a decade. VATS procedures are nowadays categorized into 2 groups. One is a modified open procedures through a mini-thoracotomy with customization of conventional instruments. The other is a port-access procedure with use of newly developed instruments for endoscopic surgery. The optimal device adapting for individual surgical manipulations should be selected to make a VATS procedure safer and more feasible. The sample extraction using a bag is a most important step when VATS is completed, because the rupture of bag can result in cancer cell contamination. More useful devices adapting either for mini-thoracotomy VATS or for port-access VATS, will be developed with advancement of medical technology.

Three-dimensional printing surgical instruments: are we there yet?

BACKGROUND

The applications for rapid prototyping have expanded dramatically over the last 20 y. In recent years, additive manufacturing has been intensely investigated for surgical implants, tissue scaffolds, and organs. There is, however, scant literature to date that has investigated the viability of three-dimensional (3D) printing of surgical instruments.

MATERIALS AND METHODS

Using a fused deposition modeling printer, an Army/Navy surgical retractor was replicated from polylactic acid (PLA) filament. The retractor was sterilized using standard Food and Drug Administration approved glutaraldehyde protocols, tested for bacteria by polymerase chain reaction, and stressed until fracture to determine if the printed instrument could tolerate force beyond the demands of an operating room (OR).

RESULTS

Printing required roughly 90 min. The instrument tolerated 13.6 kg of tangential force before failure, both before and after exposure to the sterilant. Freshly extruded PLA from the printer was sterile and produced no polymerase chain reaction product. Each instrument weighed 16 g and required only $0.46 of PLA.

CONCLUSIONS

Our estimates place the cost per unit of a 3D-printed retractor to be roughly 1/10th the cost of a stainless steel instrument. The PLA Army/Navy retractor is strong enough for the demands of the OR. Freshly extruded PLA in a clean environment, such as an OR, would produce a sterile ready-to-use instrument. Because of the unprecedented accessibility of 3D printing technology world wide and the cost efficiency of these instruments, there are far reaching implications for surgery in some underserved and less developed parts of the world.

The ophthalmology microscalpel versus standard scalpels and wound healing in a rat model

OBJECTIVE

We tested the hypothesis that the ophthalmology microscalpel, compared to standard incisional instruments, causes less trauma during incisions resulting in decreased inflammation and greater tensile strength of wounds.

STUDY DESIGN

Prospective animal study.

SETTING

Animal laboratory.

SUBJECTS AND METHODS

Thirty-four Sprague-Dawley rats received dorsum skin incisions with the microscalpel, electrosurgical device, 11 blade scalpel, and 15 blade scalpel. Wounds were harvested at 1 week, 2 weeks, 3 weeks, and 6 weeks, then analyzed histologically in a blinded manner for inflammation markers and tested for tensile strength.

RESULTS

The microscalpel wounds had significantly higher tensile strength compared to the 15 blade (P = .045) and electrocautery device (P = .000) but equivocal strength to the 11 blade (P = .457). The electrocautery wounds were weaker than all 3 steel blades. No significant difference was found between the microscalpel, 11 blade, and 15 blade incisions for the 5 markers of inflammation. Electrocautery wounds had significantly worse inflammatory scores, specifically, higher angiogenesis and larger wound gap compared to the microscalpel (P = .004, P = .002), 11 blade (P = .007, P = .023), and 15 blade (P = .010, P = .003), respectively.

CONCLUSION

Microscalpel incisions result in less inflammation and increased tensile strength compared with electrocautery and higher tensile strength compared to the 15 blade in the rat model. Inflammation scores were equivocal between the microscalpel, 11 blade, and 15 blade. Our findings support the use of the microscalpel blade for facial plastic and reconstructive procedures. Prospective, randomized human studies are warranted.

Craniotomy using image-guided oscillating saw: technical note

OBJECTIVE

To describe a new craniotomic technique that eliminates burr holes and minimizes bone loss along the craniotomic line.

PATIENTS AND METHODS

Fifty burr hole free craniotomies were performed in varied locations using an image-guided micro-oscillating saw. Care was taken to avoid cutting the inner cortical layer. Upon completing the micro-oscillating saw cut the inner table could then be gently fractured along the craniotomic line with a thin bladed osteotome. Simple silk sutures were used to resecure the bone flap.

RESULTS

The craniotomic time required for this procedure ranged from 7 to 24 minutes (mean: 13 minutes). We observed no dural lacerations or signs of brain damage in any of these procedures. The use of image guidance allows a continuous measure of bone thickness along the craniotomic line. In all of the cases we report the cosmetic result was excellent.

CONCLUSION

This alternative technique of craniotomy can be used in selected cases to achieve excellent cosmetic results which avoid the time and cost of complex reconstruction techniques.

Use of the vessel sealing system in tracheostomy

BACKGROUND

Tracheostomy is a frequent, and at times semiurgent, surgical procedure. It is performed in close proximity to the thyroid gland, and in many cases requires division of its isthmus, putting a patient in danger of significant bleeding.

OBJECTIVES

To examine prospectively the feasibility of vessel sealing in tracheostomy.

METHODS

A vessel-seating device was used in 24 consecutive patients undergoing tracheostomy. There were no exclusion criteria for enrolling the patients. No other hemostatic technique was used for dividing the isthmus.

RESULTS

There were no bleeding events throughout the postoperative period. The operating time saving was 5-10 minutes.

CONCLUSIONS

Use of the vessel sealer was found to be straightforward, efficacious, rapid and safe.

New technology and applied research: what the future holds for LESS and NOTES

Rapid technological developments in the 1970's contributed to the emergence of operative laparoscopy as a revolution in surgery. In recent years, there has been a surge of interest in laparoendoscopic single-site (LESS) and natural orifice translumenal endoscopic surgery (NOTES), novel techniques that have the potential to further minimize the invasiveness and morbidity of surgery. Innovations in instrument design and in novel surgical platforms including robotic technology have rapidly been developed in an effort to enhance the future clinical applicability of these techniques. In this chapter, we review the current status and future directions of LESS and NOTES technology, focusing on the current research in the field.

[Application of a device for determination of the transplant length during operation of the aorta-coronary bypass]

Determination of the necessary length of the bypass is one of the principal stages of operation of the aorta-coronary bypass. The greatest difficulty of the determination of the bypass length is the first-priority applying of proximal anastomoses. It requires the surgeon to have great experience, the operation to be longer. It also makes it necessary to prepare a conduit of deliberately excessive length. A device is proposed for the determination of the necessary bypass length during operation of aorta-coronary bypass consisting of a crocodile grip with a fixed to it polymer tube.

[The methods for the treatment of combined nasal deformities]

The objective of this study was to improve the cosmetic outcome of the surgical treatment of combined nasal deformities performed by the author using the rhinoplastic technique in 144 patients presenting with this condition during the period from 2006 to 2010. The patients of the main (study) group underwent the surgical intervention with the use of improved technologies proposed by the author and special instruments developed for the purpose. The patients of the control group were treated by standard surgical techniques. A statistically significant decrease of the relative frequency (percentage) of secondary nasal deformities was documented in the study group compared with the control one (from 6.94% to 2.78%). It is concluded that the technologies of rhinoplastic interventions described in the present publication can be recommended for the use in the practical work of otorhinolaryngologists and plastic surgeons.

Miethke DualSwitch Valve in lumboperitoneal shunts

INTRODUCTION

Despite the existence of wide variety of shunt systems, physiological regulation of intracranial pressure in shunted patients remains a utopian dream. Lumboperitoneal shunts (LPS) have long been used for treating idiopathic intracranial hypertension and other types of "communicating" hydrocephalus. Although they can provide rapid and effective symptom resolution, cerebrospinal fluid (CSF) over-drainage remains a common complication of LPS. We introduce the use of the Miethke DualSwitch Valve (M-DSV) for LPS and describe our preliminary experience with these valves in managing and avoiding CSF over-drainage. This is the first description of the use of M-DSV for LPS.

MATERIALS AND METHODS

Over 6 months, we treated five patients with LPS using M-DSV. Prior to the use of the M-DSV, four patients experienced significant over-drainage symptoms secondary to LPS. Data was collected prospectively, including preoperative details and clinical outcome.

RESULTS

Five patients (age range, 22 to 71 years) were operated upon. Three patients had pseudotumor cerebri, one patient had an LPS for treatment of a posterior fossa pseudomeningocele, and one had an LPS for treatment of cauda equina syndrome secondary to lumbar dural ectasia. Four patients had a history of clinical over-drainage secondary to pre-existing LPS systems. The fifth patient had an LPS revision after the previous LPS migrated. Follow-up ranged from 5 to 11 months (mean, 7.8 ± 3 months). All patients had a good outcome with immediate resolution of over-drainage symptoms and are currently asymptomatic.

CONCLUSIONS

The use of M-DSV in LPS is an effective alternative for avoiding posture-related over-drainage and managing patients with LPS-related over-drainage symptoms. Further experience is required to address the long-term outcome, balancing sufficient drainage while preventing over-drainage.

[Hydrostream resection of the spleen in experiment]

Experimental investigation, using apparatus for hydrostream dissection of tissues, was conducted. The expediency of application of a high pressure liquid stream while performance of spleen resection in experiment was proved. The stages of the organ capsule formation and parenchyma restoration in different terms after the operation were determined.

[Further improvement of apparatuses for the hemostasis, processing and treatment of the infected wounds using high-temperature stream]

The bleeding stoppage and the wound sanitation constitute an important problem of modern surgery. There is information presented concerning the apparatuses elaboration for the bleeding stoppage, processing of the soft living tissues wounds, including the infected, during surgical operations conduction, using high-temperature stream of air. The data adduced about the apparatuses trial and preclinical investigations of the method, realized with their help, had confirmed a high efficacy of hemostasis and sanation effects as well as significant reduction of the wounds processing time.

[The state and perspectives of using hydrostream technologies in surgical practice]

The work is devoted to experimental investigation and clinical application of domestic apparatus for hydrostream dissection of tissues, the schemes and principle of its working are adduced. The methods of the operations performance in experimental animals are discussed. The processes, occurring in tissues under a liquid stream action in various terms after the operation were studied. The expediency of application in abdominal surgery of a liquid stream under high pressure was noted. The results of clinical exploitation of the apparatus proposed are adduced.

[Operative neurosurgery: personal view and historical backgrounds. 6. Positioning, instruments]

Important points of positioning and instruments at the time of performing microneurosurgery according to the traditional Zuerich school style were presented based on the experience of ca. 1,000 surgeries/year for around 13.5 years. Most of the instruments and equipment had been taken over from the time of Prof. Yaşargil. Positioning: Three positions, supine, knee-elbow and siting position were almost all the positions, which we have used and special mention was directed to the sitting position. Around 1/3 of our surgeries were done in the sitting position. Its indication includes lesions not only in the posterior fossa, but in the parieto-occipital region and in the cervico-thoracal region down to the Th5. Good fixation of the head with Mayfield 3-pin-fixation apparatus with the use of one pin mostly around the medial root of the mastoid process (thickness of the bone and small amount of soft tissue) is of cardinal importance and prevention of excessive flexion (with the one-finger breadth between the chin and its underlying neck), so that strangulation of the tracheal tube and the jugular venous system can be avoided and also the below mentioned jugular compression maneuver can be done effectively. Basic knowledge of prevention of air embolism was pointed out: knowledge of usual anatomical entrance sites of the air (emissary veins, diploic veins, veins entering into the venous sinuses, venous plexus around the craniocervical junction etc.), detection of the air entrance sites by jugular compression and their sealing with tissue adhesives Tissucol. Endotidal CO2 value should be above 4.0 kPk. Importance of reclination of the position in case of further falling down of the CO2 value was emphasized. Special mention was made about the patent foramen ovale as a risk of air embolism. Advantages of the sitting position in the performance of supracerebellar infratentorial/transtentorial SCIT/SCTT approach and transvertebralis dural ring approach TVDRA were emphasized and the use of linear incision was stressed at the time of performance of all these surgeries including the posterior circulation revascularization, occipital artery-posterior cerebral artery/superior cerebellar artery OA-PCA/SCA bypass and occipital artery-posterior inferior cerebellar artery OA-PICA bypass. As for the operating microscope, importance of the eyepiece-lens assembly with mouthpiece was emphasized. Appropriate selection of this system enables surgery of long duration in a comfortable and non-tiring condition in terms of the arm length of the surgeon and his immediate reaction especially at the time of intraoperative premature rupture of an aneurysm or of minute delicate focusing at the time of microvascular suturing without withdrawal of one or both hands from the operative field for handling the operating microscope. An arm rest enables secure, effective, precise and tireless performance of microsurgery in every operating position, so that the use of height an adjustable oil pressure driven arm rest was presented along with a simply height adjustable and easily movable chair. As for the bipolar coagulator pincette, the followings were discussed: more than three different lengths of byonett forceps, each of three different tip-sizes, with isolated tips, dosis and method of coagulation. Practically no need of monopolar coagulation was pointed out. Suction tube also should have different length and size according to the depth and situations. Its vacuum power should be regulated also in accordance with changing situation in every stage of surgery. The vacuum power is regulated at surgeon's request by scrub nurses or circulating nurses, so that the surgeon can concentrate only on the precise maneuver of the tip of the suction tube. For the same reason, foot pedals for the bipolar coagulator, drilling and trepanation should be stepped by other than the surgeon, so that he can concentrate on the tip the of instrument for precise maneuvering. As tissue destruction apparatus, we prefer to use CUSA to laser, as the former enables preservation of blood vessels at the time of tissue destruction and suction by appropriate power application. Besides these, the followings items were discussed: scissors (blunt tips), Lyla retractor (variously tapered tips and fixation or holding at the other peripheral end), drilling (turning direction adjustable, cutting and diamond burr) etc.

Use of self-closing U-clips for dural repair in mini-invasive surgery for herniated disc

OBJECT

The feasibility of a new technique of dural repair (self-closing U-clips) in mini-invasive surgery for herniated disk is demonstrated in this case report.

MATERIALS AND METHODS

A 44-year-old male patient underwent lumbar microdiscectomy at out Institute, with subsequent dural leak as surgical complication; the dural leak re-appeared even after a second intervention in which we used muscle and dural graft and fibrin glue to repair the leak. We then decided to employ self-closing nitinol- U-clip to achieve primary dural closure.

RESULTS

After the intervention the patient no more presented signs or symptoms due to the unintended durotomy, and the postoperative course was uneventful.

CONCLUSION

Self-closing nitinol U-clips (Medtronic, Inc., Minneapolis) can be used for closing a dural tear through a mini-invasive approach that could make a conventional microsuturing technique very difficult.

Complete neck clipping of internal carotid-posterior communicating artery aneurysms using bayonet-shaped aneurysm clips: technical note

Neck clipping for internal carotid-posterior communicating artery (IC-PC) aneurysms using standard straight, angled, or curved clip may result in remnant aneurysm neck. We describe complete neck clipping of IC-PC aneurysms using a bayonet-shaped clip. The bayonet-shaped clip is applied perpendicular to the long axis of the internal carotid artery (ICA), and the blades of the clip are inserted between the aneurysm neck and the ICA. Using the clip applicator, the clip is gradually rotated counterclockwise or clockwise for left or right ICA aneurysm, respectively, so that the distal and shank portions of the clip blade are located at the aneurysm neck in the posterior communicating artery (Pcom) and ICA, respectively. As a result, the distal flexure of the clip blade fits the junction of the ICA and Pcom. This technique was used in four patients with ruptured ICA aneurysms and five patients with unruptured ICA aneurysms. Postoperative cerebral angiography demonstrated no residual aneurysm neck and preservation of the Pcom in all patients. This technique is useful for cases of IC-PC aneurysm involving the origin of the Pcom.

Developing scanning probe–based nanodevices—stepping out of the laboratory into the clinic

This report focuses on nanotools based on the scanning force microscope (SFM) for imaging, measuring, and manipulating biological matter at the sub-micron scale. Because pathophysiological processes often occur at the (sub-) cellular scale, the SFM has opened the exciting possibility to spot diseases at a stage before they become symptomatic and cause functional impairments in the affected part of the body. Such presymptomatic detection will be key to developing effective therapies to slow or halt disease progression.

An innovative broken pedicle screw retrieval instrument

OBJECTIVE

To introduce a new broken pedicle screw fragment retrieval instrument, and evaluate its clinical viability and effectiveness.

METHODS

Following basic retrieval contrivance of broken pedicle screws described in literature, a new retrieval instrument was designed and developed; introducing its mechanism, technical components, and use. This innovative apparatus proved successful not only in saw bone and cadaver trials but in 10 clinical cases as well.

RESULTS

This particular unique instrument successfully retrieves broken pedicle screw fragments through original passage backing out the screw with preservation of pedicle integrity while maintaining pedicle biomechanics. No complications were observed.

CONCLUSIONS

With solid scientific theoretical planning and experimentation, the new retrieval instrument design proved clinical practicality and efficacy.

Natural orifice translumenal endoscopic surgery (NOTES)

Surgery has rapidly evolved as new technologies are adopted. With the introduction of laparoscopic surgery, patient outcomes have improved, with faster recovery from smaller incisions. In an effort to continually improve these outcomes and offer alternative options to higher risk patients, a number of investigators have proposed the concept of operating in the peritoneal space through natural orifices, obviating the need for any abdominal skin incisions. Natural orifice translumenal endoscopic surgery (NOTES) offers the same advantages as laparoscopic surgery without skin incisions, and possibly without general anesthesia. This article gives a conceptual and technical description of NOTES, discusses its challenges and potential pitfalls, reviews the early efforts at NOTES-specific device development, and predicts potential future directions of this exciting new area of surgery.

Quantification of true in vivo (application) accuracy in cranial image-guided surgery: influence of mode of patient registration

OBJECTIVE

Very few studies have attempted to quantify the true (application) accuracy of image-guidance systems during craniotomy. This is, in part, because of the lack of millimetric intraoperative targets to allow such measurements. Few in vivo studies have compared the influence of mode of patient registration on subsequent true accuracy.

METHODS

Seven modes of patient registration (anatomic landmarks, 5 or 10 adhesive fiducials, bone-implanted fiducials [Stryker-Leibinger], surface matching using 45 or 100 points over scalp convexity or nose/auditory meatus contours) were compared. Thirty patients were involved in the study. Millimetric targets (bone drill holes or deep 1-mm titanium hemoclips) were placed then localized and saved at surgery. These targets were then identified on postoperative volumetric computed tomography fused with operative data sets. Localization errors of the targets were measured for each registration on an optical image-guidance system (StealthStation).

RESULTS

Only implanted cranial fiducials had a statistically significant accuracy advantage (1.7 +/- 0.7 mm). All other registrations had similar accuracies (approximately 4.0 +/- 1.7 mm) except anatomic landmarks, which were worse (4.8 +/- 1.9 mm). Calculated accuracies (root mean squared) had no predictive value for true (application) accuracies.

CONCLUSION

Not surprisingly, application accuracy of image-guidance is worse without implanted cranial markers. Unexpectedly, there was no major difference in localization of deep targets between the other registrations tested in this study. Care must be taken when using image-guidance tools to consider error introduced by registration. Cranium-implanted fiducials should be considered when high accuracy and reproducibility are needed.

A new scaled microgauge for use in neurosurgery

A new scaled microgauge is described for measuring anatomical structures during microsurgery. The instrument has a tip marked in millimetres, which can be positioned in any desired angle enabling measurement in confined areas.

Teaching Surgical Techniques and Procedures Using Advanced Educational Tools and Concepts

New educational concepts and tools are being developed to remodel surgical education. This is, in part, being driven by changes in the public's expectations of our profession along with new students seeking a different model of education. The explosion of new surgical procedures and technologies has amplified the importance of remodelling how we teach and train. At the heart of any educational experience should be a curriculum that is flexible enough to change with the content and educational tools available, but robust enough to deliver to the trainee the skills and foundation they need to safely and efficiently move through the complex medical education system that is evolving worldwide today. Here, we describe such a curriculum with great future promise to meet these expectations.

Alternative surgical dissection techniques

The bipolar scissors, coblator, harmonic scalpel, and somnoplasty techniques are widely available and offer new choices for the operating arena. There are advantages and disadvantages to all four techniques. With time, these dissection methods will prove their lasting power. Otolaryngologists have already begun to expand their applications and will surely play a role in their use and development.

Is surgical clipping becoming underused?

Coil embolization is a treatment for intracranial aneurysms with a particular appeal for posterior circulation aneurysms. However, although this procedure is effective in well-selected intracranial aneurysms, it has a series of limitations that may be overlooked as a result of its rapid technological evolution and its minimally invasive appearance. The author analyses the data that lead him to consider that since the introduction of coil embolisation in 1991 and its progressive diffusion, the technique of surgical clipping risks being underused as a therapeutic procedure for intracranial aneurysms because of the shortage of vascular neurosurgeons trained and experienced in its use.

Trends in the modes of delivery and their impact on perinatal mortality rates

OBJECTIVE

To determine changes in the incidence of vaginal deliveries, cesarean sections, and forceps deliveries and their potential association with fetal, early neonatal, and perinatal mortality rates over time.

METHODS

A retrospective study was carried out and the occurrence of deliveries supervised by university services between January 1991 and December 2000 was determined. Data regarding fetal, early neonatal, and perinatal deaths were assessed using obstetric and pediatric records and autopsy reports.

RESULTS

Of a total of 33,360 deliveries, the incidence of vaginal deliveries, cesarean sections, and forceps deliveries was relatively steady (around 60, 30, and 10%, respectively) while, at the same time, there was a marked reduction in fetal mortality (from 33.3 to 13.0 per thousand), early neonatal mortality (from 30.6 to 9.0 per thousand), and perinatal mortality (from 56.4 to 19.3 per thousand).

CONCLUSIONS

The marked reduction in perinatal mortality rates seen during the study period without an increase in cesarean sections indicates that the decrease in perinatal mortality was not impacted by cesarean section rates. The plausible hypothesis seems to be that the reduction in perinatal mortality of deliveries performed under the supervision of university services was more likely to be associated with better neonatal care rather than the mode of delivery.

Evolution of staples and clips for vascular anastomoses

Because of the development of less invasive surgical techniques, there is an increasing demand for vascular anastomosing techniques that require less exposure of the operating field. This paper reviews the most important representatives of staples, clips, and other mechanical devices for vascular anastomosing described over the last five decades. This report is organized in three parts: (1) the history of clipping and stapling devices, (2) development of the Vessel Closure System (VCS) clips, and (3) current and potential status of mechanical vascular anastomotic devices. A Medline literature search was conducted and publications on the use of staples and/or clips for the creation of vascular anastomoses identified with extensive cross-referencing. The first literature description of a mechanical vascular stapling device was by Gudov in 1950. This and other reports from the Soviet Union stimulated brisk, competitive development of vascular anastomotic devices in Europe, North America, and Japan. Fasteners included staples, penetrating pin-rings, or toothed stainless steel clips, none of which gained acceptance because of their complexity and inability to facilitate end-to-side anastomoses. A more convenient and less traumatic anastomotic system (VCS Clip applier system) was introduced into clinical practice in 1995. This system differs from staples in that it is non-penetrating. A wide variety of reports have described the advantages, both technical and biological, that clips provide over conventional needle-and-suture, particularly for the construction of vascular access for hemodialysis. A steady evolution of mechanical vascular anastomotic devices has sought to eliminate the technical and biological disadvantages of conventional suturing. Although the conventional hand-sewn, overcast non-absorbable suture remains the "gold" standard, newer techniques such as the non-penetrating arcuate-legged VCS clips are gaining acceptance as a useful addition to the vascular surgeons' armamentarium.

Disruptive visions: biosurgery

There are a number of new therapeutic options generated by the biotechnology, bioengineering, and bioimaging revolutions in terms of organ-specific designer drugs, genetically engineered cells, cell-specific proteins and drugs, directed energy instruments, therapeutic microdevices, etc. Many of these new therapies need to be placed exactly on, within, or adjacent to an organ, and many others are delivered by endoluminal or endovascular approaches. The common requirements are (1) the accurate delivery of the modality and (2) the functional importance of targeting the biologic basis rather than the anatomic structure--hence the term biosurgery. As more of these therapies achieve clinical applicability and FDA approval, there will be the need for the precision of delivery to be at the micro- and nanoscale, which is well beyond human physical limitations. The surgeon of the future must be able to identify those therapeutic modalities that would benefit from such exact placement or implantation and acquire the skills, training, and equipment to use surgical expertise to deliver these new modalities. A review of some of the emerging opportunities is presented. Ignoring these challenges will relinquish these new procedures to other nonsurgical interventionalists, perhaps to the detriment of patient safety.

Ancillary instrumentation for ureteroscopy

As the quality of ureteroscopy continues to improve, ancillary instrumentation will advance. The endourologist now has a vast supply of specially designed guidewires, stents, balloons, and baskets. These technologies have expanded the realm of cases that may be managed endoscopically. As the urologist becomes more familiar with the options at his or her disposal, patient care will improve.

FDA regulation of technology and surgical devices in the operating room

Federal regulation of medical devices began in 1976 with the signing of the Medical Device Amendments to the Food, Drug and Cosmetic Act. For the purpose of regulating medical devices, the Food and Drug Administration is divided into various divisions and branches, including the Office of Device Evaluation. The evolution of the Food and Drug Administration's regulations of laparoscopic devices is described. Also described is the technology of laparoscopic surgical devices and how they are regulated by the Office of Device Evaluation. Trends towards the future of laparoscopic devices, and their regulation, are reviewed.

Can current technology be integrated to facilitate laparoscopic living donor hepatectomy?

BACKGROUND

Living donor hepatectomy (LDH) is a technically demanding procedure that is an alternative for providing livers for transplantation. Unlike liver resections for other pathology, LDH requires preservation of the major vessels and biliary tree. This study was performed to determine if current technology can be integrated to perform laparoscopic LDH.

METHODS

Six adult sheep underwent laparoscopic LDH of the left lateral segment under general anesthesia. Instruments utilized included standard dissecting instruments, ultrasound, ultrasonic dissectors, CUSA, the TissueLink Floating Ball, and endoscopic staplers.

RESULTS

LDH-harvested liver grafts were 44% of whole liver weight. Estimated blood loss was 300 cc. Warm ischemia time was 5-7 min. Grafts were delivered through 18-cm abdominal wounds. Major vessels and biliary anatomy were positively identified in the grafts.

CONCLUSIONS

Laparoscopic LDH can be performed with available technology. Theoretical advantages include reduced liver manipulation and smaller wound size.

Improvement of the laparoscopic needle holder based on new ergonomic guidelines

BACKGROUND

The aim of this study is to create new ergonomic guidelines for the design of laparoscopic needle holders.

METHODS

An ergonomic literature study, observations in the operating room, handle-shaft angle measurements, and anthropometric data were used to compile new ergonomic criteria, specified to the function of a laparoscopic needle holder. Based on these guidelines a new needle holder was designed. The prototype and three currently available needle holders were evaluated according to the new guidelines. In addition, a pelvi-trainer test was done to measure the extreme wrist excursions.

RESULTS

The ergonomic evaluation of three commonly used handles and the new prototype indicate that the new handle is an ergonomic improvement in the field of laparoscopic needle holders: only the new handle satisfies all criteria. This is validated by the results of the pelvi-trainer test, which showed that the new prototype significantly (p <0.001) reduced the extreme wrist excursions.

CONCLUSION

The new design guidelines for a laparoscopic needle holder result in an ergonomic improvement of the instrument.

Intraoperative localization of colorectal tumors in the early stages using a magnetic marking clip detector system (MMCDS)

BACKGROUND

In the laparoscopic surgical treatment of early stage colorectal carcinomas, intraoperative tumor site identification is often difficult. We developed a novel marking method using a magnetic marking clip and a modified magnetometer system.

METHODS

We applied magnetic marking clips at the tumor site during preoperative colonoscopy and identified the clip site with a magnetic marking clip detector system (MMCDS) of our design. Eleven patients who underwent laparoscopic colectomy were studied.

RESULTS

In a basic ex vivo study, magnetic bodies of more than 300 mT magnetic force were easily detected with a 100% detection ratio. In a clinical study, the marking site was detected in all 11 patients. The mean length between the detected site and clip along the longitudinal bowel axis was 14.1 mm (SD 5.6). The mean detection time was 2.4 min (SD 0.2).

CONCLUSION

MMCDS accurately identifies tumor sites. This method may be useful for tumor site identification during laparoscopic colectomy.

The use of a remote-controlled minivalve, carried by freely moving animals on their head, to achieve instant pharmacological effects in intracerebral drug-perfusion studies

Intracerebral drug-perfusion studies in animals can be very efficiently performed with the 'reverse-dialysis' procedure. In this procedure, drugs are delivered into the brain via an intracerebrally implanted microdialysis probe. Traditionally, in reverse-dialysis studies the flow of control and drug solutions in the microdialysis site is alternated by large and heavy valves placed far from the experimental animal. In this arrangement, the drugs travel from the fluid-alternating device for a long (20--60 min) period before reaching the brain. This can obscure the onset of drug action, makes it difficult to deliver drugs into the extracellular space during short-lasting behavioral episodes, and considerably limits the number of drug solutions that can be perfused within an experimental session. This report describes the use of a miniature (15 mm long and 8 mm diameter), lightweight (1.4 g) minivalve (patent pending) for combined neuronal recording--intracerebral microdialysis studies in freely moving rats. The device is activated remotely and carried by the animals on their head. This allows the experimenter to alternate the control and drug solutions in the intracerebral recording/dialysis site rapidly and to detect the drug-induced neuronal firing pattern changes instantly, without interfering with the animal's behavior. It is demonstrated that with this novel device the onset of drug actions on hippocampal neurons can be clearly defined and that these actions occur within 2 min after minivalve activation. Furthermore, it is demonstrated that the minivalve allows one to test a large number of drug solutions, successively, within the same experimental session. The described protocol offers a high-throughput method for testing the neuron-specific pharmacological effects of intracerebrally perfused drugs during various behaviors.

Development of an ultrasonically activated trocar system

BACKGROUND

Although rare, visceral and vascular injuries related to the insertion of conventional laparoscopic trocars may have disastrous consequences. Most of these injuries are due to the high puncture force applied to the trocar. We present the results of an animal laboratory evaluation of a newly developed ultrasonically activated trocar.

METHODS

A total of 40 punctures were made in four pigs with an average weight of 53 kg. An 11-mmHg pneumoperitoneum was created through a Veress needle. A 10-mm diameter trocar was inserted in the midline for a laparoscope. A series of five trocars were then inserted on each lateral wall under laparoscopic control. Twenty punctures were made with a conventional reusable 11-mm trocar (CT) whose tip was sharp and conical. Twenty punctures were made with an 11-mm ultrasonically activated trocar (UT), whose fequency was 23.5 KHz and amplitude 150 mm. The cutaneous incision was made large enough so that the skin did not interfere with the trocar insertion. The force applied to the trocar was measured with a push-pull gauge connected to a computer. The following data were recorded: maximal force applied to the trocar to obtain insertion of the tip through the abdominal wall, maximum abdominal pressure increase during trocar insertion, and time for abdominal penetration.

RESULTS

The average time needed for trocar penetration was 12.8 s with CT and 4.5 s with UT (p < 0.001). The average maximal force was 6.8 kgF with CT and 0.4 kgF with UT (p < 0.001). The average abdominal pressure increase was 7.6 mmHg with CT and 0.8 mmHg with UT (p < 0.001). At 30 days, no necrosis was found. Pathological findings were similar in both groups.

CONCLUSION

Ultrasonically activated trocars required less time and much less force to be inserted. This may be a breakthrough in the safety of trocar insertion.

Improved usability of a new handle design for laparoscopic dissection forceps

BACKGROUND

Recent studies have shown that the shape of most instrument handles causes user discomfort and that none of the handles currently available on the market satisfies all ergonomic criteria. Therefore, we designed a handle with improved usability; i.e., it is easier to manipulate and its use entails less risk of injury for the operator. The aim of this study was to demonstrate that the intended improvements of the new design were successful.

METHODS

Six handles representative of the types that are currently available were compared with the new version. Eight surgeons used the seven handles during a precision task and a rough task in a pelvi-trainer. A questionnaire and video analyses were used to assess the usability of the handles.

RESULTS

Based on the responses to the questionnaire, we determined that there were significant differences between the new handle and the Aesculap handle (means of rotation and angle between handle and shaft). No significant differences were found between the new handle and the five other handles. The video analyses (documenting extreme vs neutral wrist excursions) showed significant differences between the new handle and the six other handles.

CONCLUSION

Compared to the six existing handles, the new handle has significantly improved usability; in particular, its hinged design obviates the need to make extreme wrist excursions.

Subfascial endoscopic perforator vein surgery (SEPS) using the ultrasonic scalpel

Subfascial endoscopic perforator vein surgery (SEPS) was recently introduced as a minimally invasive method to ligate incompetent perforating veins in patients with severe chronic venous insufficiency of the lower extremities. Herein we describe a technique in which we used a 5-mm ultrasonic scalpel for the transection of perforating veins in 16 SEPS performed in 14 patients. The use of the ultrasonic scalpel allowed for the precise coagulation and transection of the perforator vein with hemostasis, while avoiding the use of metal clips. Our initial results showed that the technique was feasible with minimal morbidity. We recommend the use of the ultrasonic scalpel as an alternative tool to transect perforating veins in SEPS.