111 resultados para microsurgery


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Transanal access is one of many currently used procedures for rectal cancer treatment. The techniques used for local excision include conventional transanal excision, posterior access, therapeutic colonoscopy and transanal endoscopic approaches. The aim of the present study was to present a new surgical proctoscope for the endoscopic transanal excision of rectal lesions. A cylindrical proctoscope with a diameter of 4 cm was devised and built. The end inserted into the anus has a bevelled aspect and rounded borders, allowing correct exposure of the anal lesion. The rectoscope is fixed to the anal border with surgical thread through perforations in the external end. A base screw holds a fibre-light which illuminates the operative field. Part of the equipment is a guide which is positioned inside the rectoscope on insertion into the anus. In operations utilizing this proctoscope, 17 adenomas, 25 adenocarcinomas, 1 carcinoid and 1 endometrioma were excised. The diameter of the lesions varied from 1 to 6 cm. The range of procedures that are possible with this new proctoscope are similar to those achieved with conventional techniques which, however, require more expensive equipment. Hence, the present study demonstrates that this newly devised low-cost proctoscope is an efficient tool for the transanal endoscopic excision of rectal lesions.

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Objective: To test the viability of a tracheal autotransplant, with an original technique using a prefabricated flap from a complete tracheal neovascularized segment (CTNVS) of the sternohyoid muscle anastomosed by a microsurgical technique. Study Design: An experimental study using dogs as an animal model. Methods: Ten mongrel dogs weighing 23 to 40 kg were divided into two groups: group I (control), five animals submitted to autotransplant of the CTNVS without a microsurgical vascular anastomosis; and group II, five dogs submitted to autotransplant of the CTNVS with a microsurgical vascular anastomosis. Results: All group I dogs developed respiratory insufficiency and died because of necrosis and stenosis of the autotransplanted CTNVS, whereas all group II dogs completed a minimum period of 90 days of observation without any clinical changes. Macro- and microscopic analysis revealed intact tracheal structures. Conclusions: The present clinical and morphological findings demonstrate that the CTNVS autotransplant is viable, when a microsurgical vascular anastomosis is used.

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Pre-operative diffusion tensor (DT) tractography is currently employed in our institutions. We use it to predict the course of the facial nerve (FN) in the vicinity of vestibular schwannomas (VS) of the cerebellopontine angle (CPA). In this study we were interested to assess the inter-observer reproducibility of this method. Two Neuroradiologists (PMGP and TT) determined independently the location of the FN by tractography and compared the results with in-vivo findings of microsurgery of VS.

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Purpose/Introduction: To determine the clinical utility of pre-operative diffusion tensor (DT) tractography of the facial nerve in the vicinity of cerebellopontine angle (CPA) tumours. The location of the facial nerve was established pre-operatively by tractography and compared with in-vivo electrode stimulation during microsurgery of vestibular schwannomas and rare CPA masses (meningiomas and arachnoid cysts).

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INTRODUCTION: Excision of large dermatofibrosarcoma protuberans in the anterior aspect of the trunk often results in large surgical defects that frequently dictate the need for microsurgical reconstruction. However, this option is not always available. PRESENTATION OF CASE: The authors describe two patients with very large anterior trunk dermatofibrosarcoma protuberans: one in the epigastric region and the other in the hypogastric region. In the patient with the hypogastric tumor, a classical abdominoplasty flap associated with umbilical transposition was used to cover the skin defect after muscle and fascial plication, and placement of a polypropylene mesh. In the patient with the epigastric tumor, a synthetic mesh was also placed, and the skin and subcutaneous defect was reconstructed with a reverse abdominoplasty flap and two thoraco-epigastric flaps. In both cases, complete closure was possible without immediate or late complications. DISCUSSION: The local options described in this paper present several potential advantages compared to microsurgical reconstruction, namely they are easier and faster to perform and teach; they provide a good skin color and texture match; they are not associated with distant donor site morbidity; follow-up is usually less cumbersome; the post-operative hospital stay tends to be shorter; they are less costly; they are less prone to complete failure. CONCLUSION: The authors believe that these two patients clearly show that local flaps, although frequently neglected, continue to be valid options for reconstructing large anterior trunk defects, even in the current era of microsurgery enthusiasm.

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Microlaparoscopy represents the development of endoscopic surgery towards a minimally invasive surgical procedure. The advantages include fewer surgical complications, faster return to daily activities, more comfortable postoperative recovery, and satisfactory aesthetic results. The possibility of performing surgery under sedation may result in shorter hospitalization, lower hospital costs, and easier anesthetic procedures. The authors report their preliminary experience with the use of microlaparoscopy, using optics and 2mm instruments, as well as a review of the literature since the introduction of this new technique. The report of these 16 cases demonstrates that microlaparoscopy is a feasible technique with satisfactory results. On the other hand, this new technique requires precise indications and a training period for the development of the skills necessary for performing these surgeries.

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Background The distally based anterolateral thigh (ALT) flap is an interesting reconstructive solution for complex soft tissue defects of the knee. In spite of a low donor site morbidity and wide covering surface as well as arch of rotation, it has never gained popularity among reconstructive surgeons. Venous congestion and difficult flap dissection in the presence of a variable anatomy of the vascular pedicle are the possible reasons.Methods An anatomical study of 15 cadaver legs was performed to further clarify the blood supply of the distally based ALT. Our early experience with the use of preoperative angiography and a safe flap design modification that avoids distal intramuscular skeletonization of the vascular pedicle and includes a subcutaneous strip ranging from the distal end of the flap to the pivot point is presented.Results The distally based ALT presents a constant and reliable retrograde vascular contribution from the superior genicular artery. Preoperative angiography reliably identified and avoided critical Shieh Type II pedicled flaps. The preservation of a subcutaneous strip ranging from the distal flap end to the upper knee was associated with the absence of venous congestion in a short case series.Conclusions Preoperative angiography and a flap design modification are proposed to allow the safe transfer of the distally based ALT to reconstruct soft tissue defects of the knee.

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Traumatic injuries resulting in peripheral nerve lesions often require a graft to bridge the gap. Although autologous nerve auto-graft is still the first-choice strategy in reconstructions, it has the severe disadvantage of the sacrifice of a functional nerve. Cell transplantation in a bioartificial conduit is an alternative strategy to create a favourable environment for nerve regeneration. We decided to test new fibrin nerve conduits seeded with various cell types (primary Schwann cells and adult stem cells differentiated to a Schwann cell-like phenotype) for repair of sciatic nerve injury. Two weeks after implantation, the conduits were removed and examined by immunohistochemistry for axonal regeneration (evaluated by PGP 9.5 expression) and Schwann cell presence (detected by S100 expression). The results show a significant increase in axonal regeneration in the group of fibrin seeded with Schwann cells compared with the empty fibrin conduit. Differentiated adipose-derived stem cells also enhanced regeneration distance in a similar manner to differentiated bone marrow mesenchymal stem cells. These observations suggest that adipose-derived stem cells may provide an effective cell population, without the limitations of the donor-site morbidity associated with isolation of Schwann cells, and could be a clinically translatable route towards new methods to enhance peripheral nerve repair.

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The treatment of morphoeic (or sclerosing) basal cell carcinoma (mBCC) of the face is associated with high rates of incomplete excision and recurrence. A principal risk factor for incomplete resection is the grade of surgeon. We did a prospective, randomised study of 40 consecutive patients with mBCC of the face. The extent of the tumour was assessed under standard conditions by consultant surgeons and compared with assessments by resident surgeons with the help of the Varioscope, a combination of microscope and loupe glasses with strong illumination and a maximal magnification of 7x. The data from a former retrospective study of all excisions of mBCC of the face during a five-year period at the hospital served as control. Residents with the support of the Varioscope achieved a rate of incomplete excisions similar to that of consultants under standard conditions. There was a significant reduction of the rate of incomplete resections by resident surgeons thanks to high magnification and good lighting (p=0.02). High magnification and good lighting were useful in learning how to recognise skin changes associated with mBCC of the face and achieving a low rate of incomplete excisions.

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BACKGROUND Dermatologic surgeons routinely harvest pedicled flaps at distance with an axial or random pattern to repair facial defects. These types of skin flaps are time-consuming and have high economic, social and personal costs. These drawbacks could be avoided with the introduction of a single-step transfer of free flaps to the recipient site, with microvascular anastomosis. OBJECTIVE To demonstrate that better results are obtained with myocutaneous or fasciocutaneous free flaps and which one is more suitable in surgical dermatology. MATERIAL AND METHODS We selected two patients of opposite sexes and similar ages who had undergone Mohs surgery to remove recurrent malignant tumors that were located in the upper cheek bordering the zygomatic zone. The woman was treated with a fasciocutaneous radial free flap and the man with a rectus abdominis free flap. RESULTS Both patients had excellent immediate postoperative outcomes. Complications observed in the male patient were related to a previous pulmonary alteration. The fasciocutaneous radial free flap reconstruction was easier to perform than the rectus abdominis free flap; nevertheless, the radial free flap is very thin and, although the palmaris longus tendon is used, it does not yield enough volume, requiring later use of implants. In contrast, the rectus abdominis free flap transfers a wide flap with enough fat tissue to expand in the future. As for the cosmetic results regarding the donor site, the rectus abdominis free flap produces better-looking scars, since secondary defects of the palmar surface cannot be directly closed and usually require grafting - a situation that some patients do not accept. CONCLUSIONS In surgical dermatology, each case, once the tumor has been extirpated, requires its own reconstructive technique. The radial free flap is suitable for thin patients who are willing to cover their arm with a shirt. The rectus abdominis free flap is best suited for obese patients with deep and voluminous defects, although it is necessary to dislocate the navel from its original position.

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Aim: The management of large lesions of the skull base, such as vestibular schwanommas (VS), meningiomas (MEN) or pituitary adenomas (PA), is challenging, with microsurgery remaining the main treatment option. Planned subtotal resection is now being increasingly considered to reduce the risk of neurological deficits following complete resection. The residual part of the tumor can then be treated with Gamma Knife Radiosurgery (GKR) to achieve long-term growth control. Methods: This case series documents early results with planned subtotal resection followed by GKR in Lausanne University Hospital, between July 2010 and March 2012. There were 24 patients who underwent surgery, with 22 having already undergone GKR and 2 waiting for GKR. We analyzed clinical symptoms for all patients, as well as audiograms, ophthalmological and endocrinological tests, when indicated. Results: Nine patients had VS surgery (mean diameter 35 mm; range 30-44.5) through a retrosigmoid approach. There were no post-operative facial nerve deficits. Of the 3 patients whom had useful hearing pre-operatively, this improved in 2 and remained stable in 1. Four patients with clinoid MEN (mean diameter 26.5 mm; range 17-42) underwent subtotal resection of the tumor, and the component in the cavernous sinus was later treated with GKR. The visual status remained stable in 3 patients and one had complete visual recovery. 4 patients underwent subtotal resection of petro-clival MEN (mean diameter 36 mm; range 32-42): 3 had House-Brackmann (HB) grade 2 facial function that recovered completely; one continues to have HB grade 4 facial deficit following surgery. Of the 7 patients with PA (mean diameter 34.5 mm; range 20-54.5), 2 had acromegaly, the others were non functional PA. Six patients underwent trans-sphenoidal surgery, while one patient had a transcavernous sinus resection of the tumor (with prior staged trans-sphenoidal surgery). Visual status improved in 3 patients while the others remained stable. Two patients had transient diabetes insipidus following surgery. Up to now, no additional deficit or worsening has been reported after GKR. Conclusions: Our data suggest that planned subtotal resection has an excellent clinical outcome with respect to preservation of cranial nerves, and other neurological functions, and a good possibility of recovery of many of the pre-operative cranial nerve dysfunctions. The results in terms of tumor control following GKR need further long-term evaluation.

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INTRODUCTION: The management of large lesions of the skull base, such as vestibular schwannomas (VS) is challenging. Microsurgery remains the main treatment option. Combined approaches (planned subtotal resection followed by gamma knife surgery (GKS) for residual tumor long-term control) are being increasingly considered to reduce the risk of neurological deficits following complete resection. The current study aims to prospectively evaluate the safety-efficacy of combined approach in patients with large VS. MATERIALS AND METHODS: We present our experience with planned subtotal resection followed by gamma knife surgery (GKS) in a consecutive a series of 20 patients with large vestibular schwannomas, treated between 2009 and 2014 in Lausanne University Hospital, Switzerland. Clinical and radiological data and audiograms were prospectively collected for all patients, before and after surgery, before and after GKS, at regular intervals, in dedicated case-report forms. Additionally, for GKS, dose-planning parameters were registered. RESULTS: Twenty patients (6 males and 14 females) with large VS had been treated by this approach. The mean age at the time of surgery was 51.6years (range 34.4-73.4). The mean presurgical diameter was 36.7 (range 26.1-45). The mean presurgical tumor volume was 15.9cm(3) (range 534.9). Three patients (15%) needed a second surgical intervention because of high volume of the tumor remnant considered too large for a safe GKS. The mean follow-up after surgery was 27.2months (range 6-61.3). The timing of GKS was decided on the basis of the residual tumor shape and size following surgery. The mean duration between surgery and GKS was 7.6months (range 413.9, median 6months). The mean tumor volume at the time of GKS was 4.1cm(3) (range 0.5-12.8). The mean prescription isodose volume was 6.3cm(3) (range 0.8-15.5). The mean number of isocenters was 20.4 (range 11-31) and the mean marginal prescription dose was 11.7Gy (range 11-12). We did not have any major complications in our series. Postoperative status showed normal facial nerve function (House-Brackmann grade I) in all patients. Six patients with useful pre-operative hearing (GR class 1) underwent surgery with the aim to preserve cochlear nerve function; of these patients, 5 (83.3%) of them remained in GR class 1 and one (16.7%) lost hearing (GR class 5). Two patients having GR class 3 at baseline remained in the same GR class, but the tonal audiometry improved in one of them during follow-up. Eleven patients (57.8%) were in GR class 5 preoperatively; one patient improved hearing after surgery, passing to GR class 3 postoperatively. Following GKS, there were no new neurological deficits, with facial and hearing function remaining identical to that after surgery. CONCLUSION: Our data suggest that planned subtotal resection followed by GKS has an excellent clinical outcome with respect to retaining facial and cochlear nerve function. This represents a paradigm shift of the treatment goals from a complete tumor excision perspective to that of a surgery designed to preserve neural functions. As long-term results emerge, this approach of a combined treatment (microsurgery and GKS) will most probably become the standard of care in the management of large vestibular schwanomma.

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This 30-year-old woman presented with clinical symptoms and signs of intracranial hypertension and Parinaud syndrome secondary to ventriculoperitoneal shunt dysfunction. Magnetic resonance (MR) imaging revealed gross triventricular hydrocephalus with a large suprapineal recess due to aqueductal stenosis. Using an endoscopic approach, a ventriculostomy was performed within the floor of the dilated suprapineal recess. Following this procedure the patient experienced alleviation of all her neurological symptoms and signs. Postoperative MR imaging and cerebrospinal fluid flow studies demonstrated a functioning ventriculostomy. The anatomy of the suprapineal recess and its suitability for endoscopic ventriculostomy are discussed.

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OBJECTIVE: Patients with intractable epilepsy due to extensive lesions involving the posterior quadrant (temporal, parietal, and occipital lobes) form a small subset of epilepsy surgery. This study was done with a view to analyze our experience with this group of patients and to define the changes in the surgical technique over the last 15 years. We also describe the microsurgical technique of the different surgical variants used, along with their functional neuroanatomy. METHODS: In this series there were 13 patients with a median age of 17 years. All patients had extensive presurgical evaluation that provided concordant evidence localizing the lesion and seizure focus to the posterior quadrant. The objective of the surgery was to eliminate the effect of the epileptogenic tissue and preserve motor and sensory functions. RESULTS: During the course of this study period of 15 years, the surgical procedure performed evolved toward incorporating more techniques of disconnection and minimizing resection. Three technical variants were thus utilized in this series, namely, (i) anatomical posterior quadrantectomy (APQ), (ii) functional posterior quadrantectomy (FPQ), and (iii) periinsular posterior quadrantectomy (PIPQ). After a median follow-up period of 6 years, 12/13 patients had Engel's Class I seizure outcome. CONCLUSION: The results of surgery for posterior quadrantic epilepsy have yielded excellent seizure outcomes in 92% of the patients in the series with no mortality or major morbidity. The incorporation of disconnective techniques in multilobar surgery has maintained the excellent results obtained earlier with resective surgery.