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At least 199 records · Page 11Linked to original sources

Pulsed angiolytic laser treatment of ectasias and varices in singers.

OBJECTIVES: Varices and ectasias in singers are typically the result of phonotraumatic shearing stresses and/or collision forces on the microcirculation within the superficial lamina propria. These lesions can be debilitating in performing vocalists because of the effect of recurrent hemorrhage and/or as a contributing factor to the morbidity of other mass lesions such as polyps, nodules, and cysts. Phonomicrosurgical treatment of performers is understandably approached with great trepidation, as the vocal liability of surgically disturbing the superficial lamina propria and epithelium must be balanced with the inherent detrimental vocal effect(s) of the lesion(s). Pulsed angiolytic lasers that emit radiation at high absorbance peaks of oxyhemoglobin were examined to determine whether they were an efficacious treatment approach for ectasias and varices based on these lasers' mechanisms of action and prior experience in phonomicrosurgery. METHODS: A prospective trial was done in 39 patients (40 procedures in 54 vocal folds) without complication to evaluate the effectiveness of a 585-nm pulsed dye laser (PDL; 25 cases) and a 532-nm pulsed KTP laser (15 cases) in a noncontact mode to treat 65 varices and 43 ectasias. Twenty-nine of 39 patients had varices and ectasias associated with other phonotraumatic mass lesions that required resection. RESULTS: All patients have resumed full vocal activities, and no patient has had a subsequent hemorrhage or vocal deterioration. CONCLUSIONS: Both the 585-nm PDL and the 532-nm pulsed KTP laser were found to be efficacious and relatively safe treatment modalities for vascular abnormalities of the vocal folds in singers. Noncontact selective photoangiolysis of the aberrant vessels prevented future bleeding without substantial photothermal trauma to the overlying epithelium and surrounding delicate superficial lamina propria, thereby allowing for optimal postoperative mucosal pliability and glottal sound production. However, the pulsed KTP laser was substantially easier to use because of its enhanced hemostasis due to its longer pulse width. Vessel wall rupture was commonplace during use of the 585-nm PDL, but rarely occurred during photoangiolysis with the 532-nm pulsed KTP laser.

Dilatation, Pathologic↗

Comparison of the chondrogenic potential of free and vascularized perichondrium in the airway.

Revascularized perichondrium or periosteum may be the ideal graft to repair severe laryngotracheal stenosis because of its pliability, potential for bone or cartilage formation, resistance to infection, and rapid mucosalization. To begin our evaluation of these grafts in airway reconstruction, this study was designed to quantify the chondrogenic capacity of free and vascularized perichondrium placed in the airway. In a rabbit model, free auricular perichondrium (N = 16) produced a mean cartilage thickness of 0.15 mm, whereas vascularized auricular perichondrium (N = 18) produced a mean of 0.45 mm at 8 weeks (p < .0001). In a third group of rabbits (N = 4) vascularized auricular perichondrial grafts were subjected to a 2-hour intraoperative ischemic insult in order to simulate the ischemia of revascularization. The mean cartilage thickness at 8 weeks was 0.50 mm. We conclude that in the rabbit model, vascularized perichondrium provides significantly more cartilage than free perichondrial grafts.

Animals↗

Vocal fold submucosal infusion technique in phonomicrosurgery.

Phonomicrosurgery is optimized by maximally preserving the vocal fold's layered microstructure (laminae propriae). The technique of submucosal infusion of saline and epinephrine into the superficial lamina propria (SLP) was examined to delineate how, when, and why it was helpful toward this surgical goal. A retrospective review revealed that the submucosal infusion technique was used to enhance the surgery in 75 of 152 vocal fold procedures that were performed over the last 2 years. The vocal fold epithelium was noted to be adherent to the vocal ligament in 29 of the 75 cases: 19 from previous surgical scarring, 4 from cancer, 3 from sulcus vocalis, 2 from chronic hemorrhage, and 1 from radiotherapy. The submucosal infusion technique was most helpful when the vocal fold epithelium required resection and/or when extensive dissection in the SLP was necessary. The infusion enhanced the surgery by vasoconstriction of the microvasculature in the SLP, which improved visualization during cold-instrument tangential dissection. Improved visualization facilitated maximal preservation of the SLP, which is necessary for optimal pliability of the overlying epithelium. The infusion also improved the placement of incisions at the perimeter of benign, premalignant, and malignant lesions, and thereby helped preserve epithelium uninvolved by the disorder.

Epinephrine↗

Fat implantation into Reinke's space: a histologic and stroboscopic study in the canine.

The scarred vocal fold is a cause of persistent dysphonia after laryngeal trauma, microsurgery, and tumor resection. The loss of Reinke's space with scar and stiffness is the primary cause. This study explores the technical aspects of endoscopic implantation of fat as an autologous implant for restoring the bulk and pliability of the vocal folds. Fat from the buccal area was harvested and prepared in 6 dogs. A mucosal flap submucosal pocket was prepared by means of microlaryngoscopy instrumentation. The fat implant was placed into the submucosal pocket. The mucosal flap was sutured endoscopically. Six weeks later, the larynx was harvested and mounted, and vocal fold oscillation was studied while driven by a humidified flow source. The vibratory patterns were studied by stroboscopy. Histologic sections of the vocal folds were made in the coronal plane. All 6 specimens had histologic evidence of viable implanted fat and/or fibrous tissue at the implant site. The site of implantation was in the superior aspect of the vocal fold, but contributed to mass in vocal fold bulk. This increase in bulk histologically corresponded to stroboscopic evidence of increased mass. On stroboscopy, the implant side continued to demonstrate good vibratory function. The study shows that fat implantation can be carried out as an endoscopic procedure. Fat implantation may be useful as a surgical procedure for restoration of Reinke's space. It may be applicable in patients with scars, sulcus vocalis, or vocal fold atrophy.

Adipose Tissue↗

Transverse cervical artery fasciocutaneous free flap for head and neck reconstruction: initial anatomic and dye studies.

METHOD: The bilateral transverse cervical arteries of 16 fresh cadavers were exposed by an infraclavicular midline approach. Each artery was cannulated, and methylene blue dye was infused to delineate the skin territory subserved by the vessel. The two major infusion skin patterns obtained allowed fashioning of a thin fasciocutaneous flap incorporating supraclavicular skin, which was based on the transverse cervical artery; or a larger flap additionally incorporating upper back skin and varying amounts of trapezius muscle, when the artery had a dorsal scapular artery branch. Depending on the skin pattern, either scapula or clavicle could be transferred with the other soft tissues. RESULTS: The skin territory of the transverse cervical artery is caused to vary by the presence or absence of its dorsal scapular artery branch. The supraclavicular portion of the flap is recommended for repair of facial and nasal lesions because of its close match in color and texture to facial skin. Oral lesions can also be reconstructed with this flap because of its pliability. CONCLUSION: The free flap based on the transverse cervical artery pedicle appears to be a useful addition to the armamentarium of flaps for head and neck reconstruction. Clinical use of the flap is ongoing and will be subsequently reported.

Arteries↗

Superior based trapezius flap.

The most revolutionary innovation in reconstructive surgery of the past decade is the development of the musculocutaneous flaps. These flaps permit the reconstruction of large head and neck defects in one stage. They carry an excellent reliable blood supply and the inclusion of the underlying muscle adds sorely needed bulk to the resected area. The trapezius musculocutaneous flap is one of the most versatile. Its color and texture match for facial reconstruction is excellent. Moreover, the pliability of the cutaneous component lends itself well to lining the oral cavity and the oropharynx. The trapezius musculocutaneous flap is an outstanding advance in head and neck reconstructive surgery. The discovery that it can be successfully pedicled superiorly greatly enhances its versatility.

Aged↗

Cross-sectional echocardiographic observations on the mechanism of preservation of the opening snap in calcific mitral stenosis.

Cross-sectional echocardiography (CSE) was performed on 19 patients with mitral stenosis (MS). Nine patients (group 1) had little or no mitral valve (MV) calcification; ten patients (group 2) had heavy MV calcification. An opening snap was present in each of the patients in group 1. Of the group 2 patients, five (group 2A) had an opening snap and five (group 2B) did not. CSE in the long axis revealed in group 1 patients a mobile MV with sharp anterior arching of the anterior leaflet in early diastole; in group 2A, dense echoes suggestive of calcification were noted near the tip of the MV, while the body of the leaflet was relatively thin and it arched anteriorly sharply in early diastole; and in group 2B, dense echoes were noted at the tip and body of the MV with reduction in mobility of the valve, and the sharp anterior arching of the anterior leaflet in early diastole was absent. Preservation of the OS in calcific MS depends on the distribution of calcification. Heavy calcification confined to the tip of the MV allows the anterior leaflet to arch anteriorly in early diastole, allowing preservation of the OS, whereas heavy calcification of the tip and body of the MV reduces the pliability of the valve with consequent disappearance of the OS.

Adult↗

Heliosphere Bag in the treatment of severe obesity: preliminary experience.

BACKGROUND: Various intragastric balloons have been used in obese patients for temporary weight loss. Recently, a new balloon, the Heliosphere Bag, was proposed. In a preliminary study, we evaluated the safety and efficacy of this device. METHODS: The Heliosphere Bag was used in 10 patients, selected according to the guidelines for obesity surgery. The manufacturer's instructions were followed in positioning the device. Heliosphere Bag positioning was performed, after diagnostic endoscopy, under unconscious sedation. After placement, the balloon was slowly inflated with 840-960 cc of air, which gives the inflated final volume of 650-700 cc of air, as the air is compressed. On the first and second post-treatment day, intravenous saline (30-35 ml/kg/d) with omeprazole (20 mg/d), ondansetron (8 mg/d) and butylscopolamine bromide (20 mg t.i.d.) were given to all patients. All patients from day 3 after placement began liquid diet and were discharged home on day 4 on a 1000 kcal diet (carbohydrate 146 g, lipid 68 g, protein 1 g/kg ideal weight). After 6 months, the Heliosphere Bag was removed. The patients were followed monthly, and complications and their treatment, post-placement symptoms, BMI and %EWL were recorded. Data were expressed as mean +/- SD. RESULTS: From Sept-Dec 2004, 10 patients (5M/5F) underwent Heliosphere Bag placement, with age 35.2 +/- 15.7 years (17-49), BMI 43.3 +/- 8.1 kg/m(2) (35-51.2), and weight 126.8 +/- 23.7 kg (98.4-148). Heliosphere Bag positioning was quite difficult in all patients due to low pliancy and large size of the bag, causing patient discomfort. System failure at time of Heliosphere Bag positioning was observed in 5/10 patients (50%). At time of removal, the Heliosphere Bag was not found in the stomach in one patient. In 3 other patients, the balloon was found partially deflated. At the time of balloon removal after 6 months, BMI was 37.4 +/- 13.4 (28.9-42.1) and %EWL was 29.1 +/- 20.1 (9.0-57.4). BMI loss was 5.2 +/- 13.1 (1.9-11.2) and mean weight loss was 17.5 +/- 16.2 kg (5-33). CONCLUSIONS: Although weight loss was satisfactory, this device cannot be considered an advance for the temporary treatment of morbid obesity. This balloon still has some instrumental and technical problems that need to be solved: high rate of system failure at positioning, high rate of spontaneous deflation, absence of a marker such as methylene blue, and large size with low pliability that cause significant patient discomfort.

Adolescent↗

Cell migration analyses within fibroblast-derived 3-D matrices.

Research in cell biology often is based in tissue culturing cells on artificial substrates, such as plastic or glass. These artificial conditions are prone to distorting findings by persuading cells to adjust to artificial flat rigid surfaces. In contrast, the natural substrate for most cells in living organisms is the extracellular matrix (ECM), which is three-dimensional, complex, and dynamic in its molecular composition, and variable in pliability. Here we show how to measure the rates and directionality of fibroblasts motility within physiologically relevant in vivo-like cell-derived three-dimensional matrices.

3T3 Cells↗

Contegra conduit: current outcomes and concerns.

A variety of congenital cardiac anomalies with severe right ventricular outflow tract (RVOT) obstruction or RVOT interruption require surgical reconstruction from the infundibulum up to the pulmonary artery bifurcation or even into the branches of the pulmonary arteries. Ideally, the conduit or valve required for such reconstruction has to be formed of autologous tissue that grows, resists infection, lasts for the life span of the patient and is readily available in all sizes. Such conduits, however, are not available and although several alternatives have been used, none of which are without potential drawbacks. Contegra valved bovine internal jugular vein conduit (Medtronic Inc., MN, USA) has recently emerged as a promising option for pediatric RVOT reconstruction and has been advocated for its 'off-the-shelf' availability in sizes ranging from 12 to 22 mm, surgical pliability and encouraging short- and mid-term success in experimental animal, as well as clinical studies. This review focuses on the current outcomes of Contegra conduit and highlights some of the major concerns related to the use of this conduit and strategies to tackle these concerns.

Animals↗

A new concept of ascitic fluid distribution.

Of 26 patients with ascites examined by B-mode ultrasonography, 14 had scans appropriate for evaluating the presence of fluid within the abdominal cavity. These studies demonstrate localization of fluid anteriorly around the tip of the liver and emphasize the importance of such factors as density relationships and the "pliability" of the anterior abdominal wall in the distribution of ascitic fluid. A reveiw of the literature is presented.

Ascites↗

Differences between heart valve allografts and xenografts in the incidence and initiation of dystrophic calcification.

Following surgical removal because of primary tissue failure, 30 antibiotic-sterilized human aortic valve allografts and 27 glutaraldehyde-treated porcine aortic valve xenografts were examined for macroscopic and microscopic evidence of dystrophic calcification. These grafts had been mounted on stents and used for from 34 to 166 months to replace diseased mitral valves. After explantation the grafts were carefully examined then prepared for light microscopy, for transmission electron microscopy and for energy dispersive X-ray microanalysis. Gross calcification occurred significantly (p = 0.002) more frequently in xenografts (89%), and was more extensive than in allografts (53%). Calcification usually appeared as nodular excrescences on the cusps, although occasionally it formed plates within them. This reduced tissue pliability and was usually associated with either valvular stenosis or regurgitation. The calcified deposits contained calcium and phosphate in ratios approaching those of hydroxyapatite. In xenograft valves the smallest discrete deposits of calcification were spherical and usually associated with membranous debris of porcine donor fibroblasts, but allografts did not contain donor cell remnants and early calcification was linearly arranged along collagen fibres.

Adolescent↗

Fracture healing after rigid intramedullary nailing in rats.

Rigid intramedullary nailing of the right tibia after osteotomy with resection of the fibula was performed on 48 male Wistar rats weighting 300-400 g. Nailing was performed with 1.4-mm nails after reaming. Nail stiffness was similar to that of intact tibias. The left leg remained unoperated as control. The animals were sacrificed after 4, 8, 12 or 16 weeks, and both tibiae were tested in a 3-point bending test. Of the 35 animals with the nail in situ, nine animals showed non-union at the time of testing. At 8 weeks stiffness had reached normal values, while strength and deflection showed about half of normal values. Poor strength and small deflectability combined with near normal stiffness may be taken as evidence that Wolf's law is valid also in newly formed tissues of fracture healing; the protection given by a rigid nail makes normal strength and pliability unnecessary.

Animals↗

Systemic hypotension in neurosurgery.

The authors review the intraoperative use of elective hypotension to reduce the probability of hemorrhage, to increase pliability of the aneurysmal sac for ease of clip application, and to control hemorrhage. The optimum agent and techniques for lowering systemic blood pressure remain controversial, but trimethaphan, sodium nitroprusside, and halothane have been found most useful. When cerebral blood flow falls below the brain's capacity to autoregulate, distinct time-related alterations occur biochemically and histologically. The profile of prolonged reduced adenosine triphosphate (ATP), low phosphocreatine, low glucose, and elevated lactate and lactate/pyruvate ratio is associated with swelling of perivascular astrocytes and "blebbing" of vascular endothelial cells with subsequent cerebral damage. To prevent permanent alteration it is desirable to observe time constraints and to employ other means of protection such as hypothermia, although the authors believe the latter unnecessary for short hypotensive periods. It has been proposed, but not substantiated, that anesthetics which depress rate of cerebral oxygen consumption but do not affect cerebral ATP level protect the brain from hypotension. Several investigations suggest that halothane, a vasodiltor, satisfies the safety requirement. The most prominent contraindication to halothane, however, is elevation of intracranial pressure. At present hypotensive surgery for aneurysmorrhapy is usually performed when intracranial pressure has returned to normal. Experimentally the electroencephalogram has been observed to show alterations prior to biochemical parameters for following brain vulnerability, so that it conceivably could be an effective monitoring technique during prolonged profound hypotension.

Adenosine Triphosphate↗

Polyester meshes and adhesive materials in the brain: comparative research in rats to optimize surgical strategy.

OBJECT: The goal of this study was to determine the biocompatibility of polyester mesh electrode carriers for auditory brainstem implants with and without adhesives in a rat model. METHODS: Physical properties of the meshes were evaluated within the fourth ventricle region, both without (Group A) and with adhesives (muscle, Group B; oxidized regenerated cellulose [ORC], Group C; and fibrin glue, Group D). The stability of the mesh position, the healing process, and host defense reaction after 2 to 60 days were examined in series of tissue sections in which meshes were preserved in situ. The cellular reaction was further evaluated using electron microscopy. Although otherwise pliable, polyester meshes were too rigid when used with adhesives, especially fibrin glue or muscle. Also, the sharp edges of the meshes presented a risk of brainstem and cerebellar lesions. Regardless of the material, meshes induced persistent inflammatory tissue reactions characterized by numerous macrophages and foreign-body giant cells. After 14 days, the cellular response had resulted in sufficient fibroblast and collagen fiber encapsulation of the meshes and remained essentially unchanged thereafter. No influence of adhesives on the healing process was observed, and, unexpectedly, these substances did not reduce the risk of dislocation prior to adequate cellular encasement. In some rats in Groups A and C, purulent inflammation, in part with Gram-positive bacteria, occurred after 2 to 14 days. The ORC exhibited persistent swelling, introducing the risk of occlusive hydrocephalus and/or brainstem compression. CONCLUSIONS: Polyester meshes and various adhesives exhibited acceptable biocompatibility in terms of local tissue reaction. Adhesives reduced pliability of the meshes, however, and were ineffective in reducing the risk of dislocation. Handling characteristics could be improved by better mesh designs, and risk of infection could be reduced by both improved designs and surface treatment of the meshes with antibacterial agents.

Animals↗

Use of polydioxanone absorbable monofilament sutures in orthopedic surgery.

The safety and efficacy of polydioxanone absorbable monofilament sutures was documented in 57 orthopedic surgery patients (32, dyed sutures; 25, undyed sutures), 55 of whom were followed for at least 42 days postoperatively. The other two patients were lost to follow up prior to 42 days. The final clinical outcome was excellent in all completed study subjects. No suture-related adverse effects were reported. Both dyed and undyed sutures were consistently better than surgical gut with respect to pliability, strength, ease of passage, ease of tying, fraying, knot security, and overall handling. Intraoperative visibility of dyed polydioxanone sutures was consistently superior to that of surgical gut. The visibility of undyed sutures was rated better than surgical gut in 16 cases, equal in 8, and worse in 1. Both the overall handling of the polydioxanone monofilament sutures and performance as it affected wound healing were significantly superior to those of surgical gut.

Adolescent↗

A palpable spleen is not necessarily enlarged or pathological.

It is widely accepted that a palpable spleen in the adult population is always enlarged and pathological. The aim of this study was to assess the validity of this statement. As a routine, our protocol for liver-spleen studies includes liver pliability, which demonstrates the level of the hemidiaphragms at full inspiration and expiration, as well as splenic size and colloidal uptake. Sixteen hundred 99mTc sulphur colloid liver-spleen studies, which had been performed in our Department, were reviewed. In 21 patients, who had been referred with "splenomegaly for investigation", the scintigraphic splenic size was 13 cm posterior length or less. In this group, splenic palpability was confirmed by at least two clinicians. Follow-up did not reveal any evidence of splenic disease in 18 of the 21 patients. In a separate postmortem follow-up of 123 sequential liver-spleen scans, 100 patients were noted to have a scintigraphic splenic size of 13 cm posterior length or less. This was shown to be a reliable upper limit of normal because 98% of spleens in this group weighed 250 g or less and were normal at post-mortem examination. This study demonstrates that a palpable spleen is not necessarily enlarged or pathological.

Adult↗

Open mitral commissurotomy: the 'golden standard'.

BACKGROUND AND AIM OF THE STUDY: Percutaneous balloon mitral commissurotomy (PBMC) has recently emerged as an alternative to surgical commissurotomy for the treatment of rheumatic mitral valve stenosis. However, this blind procedure may result in incomplete separation of the commissures, which could lead to accelerated restenosis. Hence, open mitral commissurotomy (OMC), which is a visually oriented procedure, remains our method of choice. This study was aimed at assessing the long-term outcome of the OMC procedure. METHODS: A series of OMC performed between 1988 and 1991, involving 100 mitral valves, each with a preoperative echocardiographic score < or =10 was investigated clinically and by echocardiography. RESULTS: Postoperatively, the mean valve area achieved was 2.89+/-0.49 cm2, compared with a mean preoperative value of 0.99+/-0.23 cm2. In a recent follow up, conducted after a mean of 8.5 years (range: 7-11 years), the mean valve area measured by echo-Doppler in this patient group was 2.37+/-0.42 cm2 (range: 1.6 - 3.6 cm2), and 81% of patients had a valve area >2.0 cm2. Reoperation was required in only two cases. The late mortality rate was 4% (0.5%/pt-yr), and was in no case valve-related. Two-thirds of the patients had no or only mild mitral insufficiency, and 93% were in NYHA functional class I or II. The nine-year actuarial survival rate was 96%, freedom from reoperation 98%, and freedom from all valve-related complications 92%. Complementary to this experience, during the past 10 years we have performed modified OMC in 919 (79%) of all 1,151 patients with mitral stenosis submitted for surgery, including 257 with mixed disease. The mean post-commissurotomy valve area (2.9 cm2) was identical to that of the study group. Moderate to severe valve calcification was not an absolute contraindication to valve conservation. CONCLUSION: OMC remains the best alternative for the treatment of all cases of mitral stenosis, independently of the degree of pliability. In our experience, the medium- and long-term results are significantly better than those usually reported in PBMC series.

Catheterization↗