Canine ureteral replacement with long acellular matrix tube: is it clinically applicable?

PURPOSE: We evaluated the effectiveness of acellular matrix used as a tube for replacement of a relatively long segment of the canine ureter. MATERIALS AND METHODS: Acellular matrix was obtained by excision of the whole ureter of donor dogs that were sacrificed and not included in the study group. Retrieved ureters were treated to have complete cell lysis, while maintaining the fiber framework. The study included 10 mongrel dogs in which a 3 cm segment was excised from 1 ureter and replaced by a tube of acellular matrix of the same length and width. The new tube was sutured proximal and distal by watertight interrupted sutures around a 5Fr Double-J stent (Medical Engineering Corp., New York, New York) that remained for 6 weeks. Excretory urography was done 1 and 2 weeks after stent removal and the dogs were then sacrificed. Before sacrifice the ureter was exposed and carefully examined, and the whole specimen was excised for histopathological examination. RESULTS: All dogs survived surgery except 1, which died 1 week postoperatively of a malpositioned stent and urinary ascites. There was no clinically apparent postoperative complications during the presence or after the removal of the ureteral stents. One week after stent removal excretory urography showed ipsilateral mild to moderate hydroureteronephrosis in 3 dogs and no dye excretion in 6 with a normal contralateral kidney. One week later no dye excretion was detected in all except 1 dog, which showed more radiological deterioration. At the time of sacrifice there was moderate to marked hydroureteronephrosis above the level of the new tube in all dogs. Although the graft was intact in all subjects, marked shrinkage was observed. On ureteral calibration there was significant narrowing of the lumen up to complete occlusion. At 8 weeks histopathological examination showed extensive fibrosis. CONCLUSIONS: An acellular matrix tube is not able to replace a 3 cm segment of the canine ureter.     

Whiplash: fact or fiction?

Cervical sprain/strain or whiplash injuries are a common cause of acute and chronic musculoskeletal impairments and are ubiquitous after rear-end automobile collisions. The diagnosis is largely subjective and the ideal treatment controversial. Unfortunately, the majority of compensated litigation claims are associated with whiplash-type injuries secondary to motor vehicle accidents. Fortunately, many recent advances have led to better understanding of the collision and injury biomechanics and to development of a prognostic classification system, objective diagnostic tests, an array of treatment modalities, and, most important, safer automobiles. These advances will undoubtedly lead to decreased incidence, a more accurate diagnosis, and a tailored management regimen resulting in improved outcomes and ultimately fewer legal proceedings.     

Scar lymphedema: fact or fiction?

BACKGROUND: Few concepts are as fundamental to plastic surgery as scarring, yet swelling within a scar and its adjacent tissues is a common observation which is not well understood. Mechanical forces, scar contracture, fibrosis, and lymph stasis have been considered as possible explanations for these edematous-appearing areas, but conclusive evidence of a cause of swelling has not been established. The purpose of this study was to evaluate the possible role of microlymphatic stasis or disruption as a causal factor. PATIENTS AND METHODS: Eleven patients (mean age: 43; range: 15 to 70) with localized swelling in conjunction with linear or curvilinear scars were evaluated, 9 with facial scars and 2 with scars of the chest wall and abdomen. Swelling within the scar had been present for an average of 4.5 years (range: 9 months to 13 years). Two patients had undergone previous Z-plasty revisions to the limbs of their curvilinear scars. Radiocolloid lymphoscintigraphy with technetium-99m Sb2S3 was performed on all patients by single or multiple injection technique into the site of the scar corresponding to local edema. RESULTS: Following injection, rapid egress of radiotracer was visualized along lymphatic pathways posterior to the scar, with continuation to locoregional nodes in all patients with U-shaped "trapdoor" or linear scar configuration. However, in 8 cases there was no evidence of lymphatic drainage traversing or bridging the scar. In 2 patients with multiple prior Z-plasty revisions to the limbs of curvilinear scars, no visualization of lymph channels across the Z-plasty flaps was apparent. In total, 8 patients were diagnosed with lymphedema of the area adjacent to or enclosed within the scar. CONCLUSIONS: These findings suggest that undrained lymphatic fluid contributes to the pathogenesis of the raised and swollen tissues seen abutting a U-shaped scar. Furthermore, as lymphatic pathways do not reestablish themselves across scars, attempts at improving lymphatic flow with Z-plasty revisions may not succeed in patients with clinical trapdoor scar deformities. Determination of scar lymphedema can assist in the selection of proper management for patients seeking scar revision.     

Drains for thyroidectomy/parathyroidectomy: fact or fiction?

BACKGROUND: Many authorities advocate draining the neck routinely after thyroid and parathyroid surgery with no scientific evidence to support this practice. We aimed to establish if the routine use of drains following thyroid/parathyroid surgery is of any value. METHOD: Medical records of patients who underwent thyroidectomy or parathyroidectomy under the care of a single endocrine surgeon (GP) over a 14-year period were reviewed. For the first 6 years, the neck was routinely drained (drain group) and for the subsequent 8 years the neck was only drained if the surgeon felt it necessary according to the operative situation (selective group). RESULTS: A total of 606 procedures (425 thyroidectomy and 181 parathyroidectomy) were performed on 582 patients. Drains were routinely used in 134 (22%) procedures (drain group) and were selectively used in 472 (78%) (selective group) of which 191 (40%) were drained. In all patients, there was a significant increase in the rate of postoperative bleeding/haematoma in patients with a drain (8/314 versus 1/282, Fisher's exact, P < 0.05). Wound infection occurred only in the patients with a drain. There was no difference in the incidence of postoperative bleeding and airways obstruction between the drain and selective groups. CONCLUSION: We conclude that the routine use of neck drains is unnecessary and may indeed be harmful, drain insertion being associated with an increased incidence of wound infection. Drains should, therefore, be used selectively after thyroidectomy and parathyroidectomy.     

Angiosome theory: fact or fiction?

The angiosome concept delineates the human body into three-dimensional blocks of tissue fed by specific arterial and venous sources named "angiosomes." Adjacent angiosomes are connected by a vast compensatory collateral web, or "choke vessels." This concept may provide new information applicable to improving targeted revascularization of ischemic tissue lesions. A few dedicated studies available seem to favor this strategy, as encouraging ulcer healing and limb preservation are reported in connection with both bypass and endovascular techniques based on these principles. The theory on the angiosome model of revascularization (AMV) may help the clinician to better refine vessel selection, vascular access, and specific strategies in the revascularization of critically ischemic legs with tissue lesions. Specific applications of angiosome-guided revascularization were recently suggested for patients with diabetes or renal insufficiency, with ischemic tissue lesions of the lower limb, and extended large- and medium-size collateral network decay. For these cases, the concept may allow deliberate arterial reconstruction following individual wound topographies in specific ischemic areas, although deprived from "rescue-vessel" supply. The AMV theory may contribute to a shift in common reperfusion options. However, the data available is suggestive and does not provide strong evidence as factors such as case mix and the severity of ischemia are unsatisfactorily controlled. At present, the evidence is scarce as to the effect of the severity of the arterial disease. In all comparisons, the groups treated are likely to be dissimilar and mismatched. The angiosome concept is postulated to be valid especially in diabetics, whose ischemic lesions tend to heal worse than those of non-diabetics.     

A vacuum device for penile elongation: fact or fiction?

OBJECTIVE: To assess the efficacy of a vacuum device as a noninvasive method for penile elongation. PATIENTS AND METHODS: Between September 2003 and November 2004, 37 sexually active men with a stretched penis length of <10 cm were given vacuum treatment three times a week, for 20 min on each occasion, for 6 months. RESULTS: After 6 months, the mean penile length had increased from 7.6 cm to 7.9 cm (no significant difference). The efficacy of vacuum treatment was approximately 10%, and the patient satisfaction rate was 30%. There was one case of haematoma of the penis and one of glans numbness, both resolved spontaneously without any intervention. CONCLUSION: Vacuum treatment of the penis is not an effective method for penile elongation, but provides psychological satisfaction for some men.     

Constipation after hysterectomy: fact or fiction?

Hysterectomy is responsible for numerous postoperative complications largely urological, but sometimes of sexual or colorectal function. The latter involve modifications of bowel function resulting in constipation as a result of delayed transit, infrequent evacuations and greater difficulty in expelling faeces. We have reviewed the topic, and consider the various hypotheses whereby these modifications may result from hormonal alterations, iatrogenic causes, or variations in recto-bladder sensitivity. Any of these could justify the modifications in bowel function detected in these patients. The studies carried out so far provide no clear information about the type of constipation that develops after hysterectomy, as we lack prospective studies that compare bowel function before and after operations. Nor is it clear whether we are dealing with constipation as a result of delayed transit or obstructed defaecation, nor which pathogenetic mechanisms are involved. In view of the large number of hysterectomies that are done, sometimes prophylactically, controlled prospective studies are warranted to address these issues more fully.     

Nephroprotection, fact or fiction?

Clinical studies of the last 15 years have shown the benefit of pharmacological interventions on the progression of chronic kidney disease, confirming the concept of nephroprotection. Pharmacological blockade of the renin angiotensin system remains the cornerstone of the nephroprotective treatment but the benefits and limitations are now better defined. The RAS blockers are all the more efficient than the proteinuria is abundant and nephroprotection is obtained in proportion to the reduction in proteinuria. Combinations of ACEI+ARA are not validated and their use should be considered only under the supervision of a specialist when optimal monotherapy has failed. The target blood pressure has been the subject of recent controversies, particularly in type 2 diabetic patients with nephropathy. The target should be individualized based on the main risk, renal or cardiovascular. Recent maneuvers have also shown a nephroprotective effect, including the correction of metabolic acidosis with sodium bicarbonate.     

Testosterone insufficiency in women: fact or fiction?

Androgen deficiency in women is a valid diagnosis in premenopausal, as well as in postmenopausal women, under certain conditions. This diagnosis is hampered by a lack of precise definitions and sensitive assays for testosterone. Precise normal ranges for control populations are lacking, and thus many studies have used pharmacological instead of physiological levels of testosterone in treatment protocols. Despite these shortcomings, and a shortage of controlled studies, there is ample evidence that testosterone treatment has helped many women with signs and symptoms of deficiency.     

Capillary pressure-induced lung injury: fact or fiction?

Lung capillary pressure in healthy humans at rest ranges between 6 and 10 mmHg. At maximal effort or in pathophysiological conditions such as left sided heart disease or massive pulmonary vasoconstriction, for example in high-altitude pulmonary disease, capillary pressure may be markedly elevated. Increased capillary pressure directly affects transendothelial fluid dynamics and thus results in the formation of hydrostatic lung edema. Excessive pressure increases may cause capillary stress failure. Recent studies, however, suggest that the microvascular response to lung capillary hypertension is more complex. Pressure, strain and shear stress cause dysfunction of the capillary endothelium characterized by an imbalanced release of vasoactive mediators. Endothelial dysfunction evokes a multicellular response with features of vasoconstriction, inflammation, and vascular leakage, thrombosis, and remodeling. These active cellular reactions contribute to the pathophysiological process and may be specifically targeted by new therapeutic strategies.     

Autoimmunity and hernia mesh: fact or fiction?

Hernia - There is an increasing number of patients following hernia surgery with implanted mesh reporting symptoms that could indicate autoimmune or allergic reactions to mesh....     

Endoscopic treatment of tracheo-esophageal fistulas: fact or fiction?

Tracheo-esophageal fistulas as a sequelae of esophageal atresia surgery are usually a severe complication whose correction requires an important surgical aggression, often with uncertain results. The possibility of treating this problem through the use of non-aggressive endoscopic methods has been described in medical literature over the last years, applying several products for occlusion with conflicting results in different publications. We present three cases of tracheo-esophageal fistulas, describing the technique of trans-tracheal endoscopic approach based on the novelty of employing a laryngeal mask which facilitates ventilation during the procedure, as well as the possibility to use endoscopic material of greater diameter. We comment on the different occlusion materials employed (Tissucol & Histoacryl) and the difficulties of their management. In one case two attempts of occlusion were made, and three in the other two, varying the application method and product. In two cases the fistulas initially reopened and in the other an occlusion was demonstrated by esophagogram and remission of respiratory symptoms during eight months was achieved. In a posterior control, a thread-like fistula reappeared but did not affect clinical improvement. The possibility to employ endoscopic techniques always seemed very promising for this type of pathology. The appearance on the market of various substances with capacity of occlusion has allowed us to employ them in comparative studies and simultaneously test the efficacy of the laryngeal mask in this kind of situations. The results show the complete ineffectiveness of some of these products and the relative possibilities of others, although in our experience we have yet to achieve any definitive occlusion.     

Immune effect of hypertonic saline: fact or fiction?

Hypertonicity affects many parts of the immune system. Animal studies and experiments in isolated cell cultures show that hypertonicity reversibly suppresses several neutrophil functions and at the same time up-regulates T-lymphocyte function. Infusion of hypertonic saline with or without colloids may thus, besides providing efficient plasma volume expansion, ameliorate the detrimental consequences on the immune function of trauma, shock, reperfusion, and major surgery. However, the few clinical studies conducted to date, specifically addressing the immune effect of hypertonic saline infusion, have shown little, if any, effect on markers of immune function, and larger clinical trials have not demonstrated benefit in terms of morbidity or mortality. Thus, as opposed to animal and cell-culture studies, the immune-modulating properties of hypertonic saline infusion would appear to be of limited value in clinical practice. This review presents in vitro studies, animal experiments, and clinical trials which investigated the consequences of hypertonic saline on markers of immune function.