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61.
62.
Topical high-molecular-weight hyaluronan and a roofing barrier sheet equally inhibit postlaminectomy fibrosis. 总被引:9,自引:0,他引:9
Wayne H Akeson Jennifer B Massie Bill Huang Alexander Giurea Robert Sah Steven R Garfin Choll W Kim 《The spine journal》2005,5(2):180-190
BACKGROUND CONTEXT: The relevance of epidural fibrosis to failed back surgical outcomes remains controversial. Previous studies on the correlation between epidural fibrosis and clinical outcome after laminectomy are inconclusive, and clinical approaches applied to reduce postlaminectomy spinal canal scarring have produced mixed outcomes. PURPOSE: Improved preclinical models are required to address the fundamental question of the relationship between postlaminectomy fibrosis and chronic pain. This study is directed at establishing small animal postlaminectomy models characterized by significantly reduced scar within the spinal canal postoperatively. Such preclinical models are offered as a platform for future studies to explore the potential relationship between postlaminectomy epidural fibrosis and persistent neuropathy with its potential for altered spinal mechanisms for pain processing, so-called spinal facilitation. Such experiments could be constructed in these models for comparison of pain behavior and its underlying neurochemistry both in the presence and absence of extensive postlaminectomy epidural scar. STUDY DESIGN/SETTING: A modified rat laminectomy model was employed to assess epidural fibrosis using a quantitative biochemical collagen assessment approach along with correlative histology. This group served as the control for comparison with groups in which antifibrotic measures were employed. We compared antifibrotic efficacy of a bioabsorbable roofing barrier sheet placed over the laminectomy defect with topical high-molecular-weight hyaluronan (HMW HA) gel, each applied postoperatively to prevent proliferative epidural scarring. Routine biomechanical tensile strength testing was employed to assess wound-healing strength. METHODS: A bilateral laminectomy (L5 and L6) with associated unilateral disc injury (L5-L6) was performed in 98 male Harlan Sprague-Dawley rats. The laminectomy models described incorporated a unilateral disc injury at L5-L6 because herniated disc material has been shown to contribute proinflammatory cytokines in the postoperative wound. Five groups were employed for the study: 1) normal controls without surgery; 2) a laminectomy-disc injury group without treatment; 3) a laminectomy-disc injury group treated with topical HMW HA gel; 4) a laminectomy-disc injury group treated with 0.2-mm thick bioabsorbable roofing barrier sheet in which a protected space was maintained between overlying paraspinous muscles and the dura and 5) a 0.02-mm thin barrier sheet treatment group in which the sheet was placed directly on the dura. The animals were sacrificed at 3- and 8-week postoperative intervals for analysis. The dissected specimens were studied biochemically for hydroxyproline content to estimate total collagen within the canal and on the dura between L4 and L7. Additional specimens were prepared histologically and stained with Masson-Goldner Trichrome stain to confirm presence of proliferative collagen and to describe the presence or absence of wound-healing scar adherence to the dura. The surgical incisions were studied biomechanically by uniaxial tensile testing to determine ultimate force, strain and prefailure stiffness. Statistics were performed using analysis of variance. RESULTS: Gross appearance and histology studies showed that the untreated laminectomy group demonstrated postoperative scar formation that is adherent between the wound and the dorsum of the dura mater in both 3- and 8-week groups. Proliferative scar was substantially increased grossly between the 3- and 8-week intervals. By gross observation there was adherence of the L5 spinal nerve to the underlying disc and adjacent pedicle on the disc injury side. Gross observation of treatment groups, in contrast, disclosed that both the 0.2-mm thick roofing barrier sheet and topical HMW HA gel each prevented scar attachment to the dural sleeve at both the 3- and 8-week postoperative intervals. Furthermore, both the HMW HA gel and 0.2-mm thick roofing barrier sheet treatment groups had significant reduction of total collagen content in the laminectomy specimens measured biochemically at the two time periods compared with the untreated controls. Histologically, the HMW HA gel and the 0.2-mm thick barrier sheet findings were consistent with the gross observations concerning lack of adherence between scar of the overlying wound and the dura. Notably, both the 0.2- and the 0.02-mm barrier sheets became enveloped by a fibrotic envelope consistent with a foreign body reaction. In the group in which the 0.02-mm thin sheet was placed within the canal on top of the dura, there was an increase of fibrosis around the sheet within the canal leading to a space-occupying mass within the canal. Although the 0.2-mm thick roofing barrier placed external to the canal became enveloped by scar, it appeared to attract proliferative scar away from the epidural space, leaving the dura relatively free of scarring or adherence to overlying tissues. The mechanical properties of the incisional wound increased significantly between 3 and 8 weeks. The ultimate strength, stress, strain and stiffness of the several groups were similar at each time point. CONCLUSION: These results provide two preclinical rat laminectomy models of potential usefulness for the future study of the relevance of epidural fibrosis to behaviorally defined pain states, and for the study of the potential of an altered neurochemical signature in postlaminectomy pain conditions. Such preclinical models have become standard in studies of pain behavior and its neurochemistry in preclinical sciatic nerve and spinal nerve injury models, and should be of utility in the studies of postlaminectomy fibrosis. There was progressive scar proliferation and maturation in the untreated postlaminectomy group in the postoperative interval between 3 and 8 weeks. HMW HA gel applied topically and a 0.2-mm thick bioabsorbable Macropore sheet used as a roofing barrier each significantly reduced postlaminectomy proliferative scar without affecting the integrity of incisional wound healing. However, if the 0.02-mm thin barrier sheet used in this study is placed within the canal in contact with the dura and adjacent to the pedicles, the process of reabsorption results in a fibrotic mass within the canal. The preferred barrier sheet placement for this model is clearly in a roofing position bridging over the open epidural space. It must be placed in a manner to block off the paraspinous muscle healing response and still leave a gap between the sheet and the dura. 相似文献
63.
The largest prospective cadaver study done over a 3-year period to investigate the arterial variations of the forehead is presented. The primary goal was to find anatomical support for various forehead flaps previously designed. Thirty cadaver foreheads (60 hemi-foreheads) were dissected from deep to superficial to identify arterial variations. The arteries were filled with a latex solution prior to dissection. The results show that the supratrochlear and dorsal nasal arteries have a relatively constant origin. Vertical (VB), oblique (OB), medial (MB) and lateral branches (LB) of the supraorbital artery were identified. The frontal branch of the superficial temporal artery (FBSTA) was found to continue in the direction of the scalp at the lateral orbital rim vertical line and gave off a transverse branch, the transverse frontal artery (TFA), to supply the forehead. The oblique branch of the supraorbital artery (OBSOA) most often anastomosed with either the transverse frontal artery or the frontal branch of the superficial temporal artery at the lateral orbital rim vertical line. A central artery (CA) was consistently found originating from the dorsal nasal artery usually 5mm from its origin. The central artery had a constant anastomosis with the opposite central artery in the inferior transverse third of the forehead. The central artery was not easily identifiable in the superior third of the forehead. The angular artery (AA) was found to have a variable termination. The angular artery could communicate with the supratrochlear artery (STrA) at the supraorbital rim (SOR) or it could continue up into the forehead medial to the STrA. This artery was called the paracentral artery (PCA). The central artery, paracentral artery and supratrochlear artery have an important relationship with the most prominent central vein that is relevant to flap construction. The significance of the central artery and vein favours the median forehead flap as anatomically superior and the prominent central vein is a constant landmark on which to select the side of the pedicle. Clear landmarks for defining the pedicle base for the median forehead flap are provided. 相似文献
64.
Shirley A. Musich Alyssa B. Schultz Wayne N. Burton Dee W. Edington 《Disease Management & Health Outcomes》2004,12(5):299-326
Corporations have engaged in sponsorship of health management programs and, more recently, disease management programs to facilitate healthy and productive work environments. The purpose of this review is to examine the health and financial outcomes from these corporate-sponsored disease management programs. This article focuses on seven diseases or chronic conditions (arthritis, asthma, cancer, depression, diabetes mellitus, heart disease, and migraine) that potentially impact employee productivity (both in time away from work and in loss of effectiveness at work) and health status including medical and pharmaceutical utilization and costs.Corporate-sponsored disease management programs typically focus on education and screening for selected diseases or chronic conditions. Partnerships have been formed with health plans and third-party program providers to reach employees with interventions and treatment. The typical outcome measures from these programs have primarily been clinical indicators and medical utilization. Measures of productivity need to be incorporated as important outcome measures for disease management programs.The estimated financial opportunity for the corporation is a reflection of the cost differential for a given disease and the prevalence of that disease within the employee population. Primary diseases, chronic conditions, and health risks contribute to increased medical utilization and decreased productivity within the corporation. Promoting programs that focus on the whole person, including health risks, chronic conditions, and diseases, will likely increase the possibility of success in helping the employee to better self-manage their health conditions and consequently provide gains for both the individual and the corporation. 相似文献
65.
66.
T Ozaki J Kondoh T Sohma R Adachi H Kurata K Imoto H Kajiwara M Tobe K Hoshino A Matsumoto 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(8):1248-1254
From 1985 to 1987, we examined relationship between the lesion of tricuspid valve and right ventricular function in 31 patients (male: 9, female: 22) with mitral valve disease. The median age at operation was 52 years (range 37-69 years). Group I consisted of 17 patients (MS: 10, MSR: 5, MR: 2) accompanied with tricuspid regurgitation (TR) and Group II 14 patients (MS: 12, MSR: 2) without TR. In all cases of Group I tricuspid annuloplasty (TAP) were performed correctly. De Vega methods were done in 12 cases and Carpentier rings were used in 5 cases. Cardiac catheterization was done before and after operation. And right ventricular volume was measured by right ventricular angiography. In both groups pulmonary capillary wedge pressure, pulmonary artery pressure and cardiac index were improved postoperatively. Pulmonary artery resistance (PAR) and total pulmonary resistance (TPR) in Group I were significantly higher before operation but there were no difference between two groups postoperatively. Right ventricular end-diastolic volume index (RVEDVI) and right ventricular end-systolic volume index (RVESVI) in Group I were significantly improved postoperatively, but in Group II these were within normal range both pre- and postoperatively. Preoperative PAR was correlated inversely with postoperative right ventricular ejection fraction (RVEF). It means that patients with severe pulmonary vascular lesion had postoperative lower right ventricular function. In both groups, RVESVI was in inverse correlation with RVEF pre- and postoperatively. In both groups, there was an inverse correlation between the per cent change of RVESVI and that of RVEF. This means that RVESVI influenced right ventricular pump function. 相似文献
67.
Primary leiomyosarcoma of the thyroid gland 总被引:1,自引:0,他引:1
Osamu Ozaki Kiminori Sugino Takashi Mimura Kunihiko Ito Seiichi Tamai Yasuhiro Hosoda 《Surgery today》1997,27(2):177-180
Primary leiomyosarcoma of the thyroid gland is extremely rare, and to the best of our knowledge only five well-documented
cases have been reported in the world literature. We herein report a 58-year-old female patient with primary leiomyosarcoma
of the thyroid who was successfully treated by total thyroidectomy with a modified neck dissection. Immunohistochemically,
the tumor cells showed positive reactivity to α-smooth muscle actin and vimentin. Radical surgery was thus considered to be
essential in the treatment of this rare but rather aggressive malignancy. 相似文献
68.
Elisabeth U. Dexter M.D. John M. Snider M.D. Ellen E.I. Gordon M.D. Wayne E. Richenbacher M.D. 《Journal of cardiac surgery》1997,12(6):412-415
A bstract One etiology of unilateral lobar pulmonary edema is mitral regurgitation. Echocardiography is able to demonstrate the retrograde flow of blood into the pulmonary veins and allows timely diagnosis and treatment planning. Correction of mitral regurgitation is followed by resolution of the radiographic abnormality. 相似文献
69.
Sherilyn Gross Karen Helm Jennifer J. Gruntmeir Wayne S. Stillman David W. Pyatt Richard D. Irons 《European journal of haematology》1997,59(5):318-326
Abstract: Our current understanding of human haematopoietic stem cell biology is based in part on the characterization of human CD34+ bone marrow cell differentiation in vitro. CD34 is highly expressed on early stem cells and haematopoietic progenitor cells with clonogenic potential and is gradually lost during differentiation and commitment. However, CD71 (transferrin receptor) is expressed at low levels on early stem cells and generally increases during haematopoietic progenitor cell proliferation. We reasoned that the combination of these surface markers would provide a useful framework for the simultaneous analysis of multiple lineage differentiation of CD34+ haematopoietic progenitor cells in liquid culture. In this report, we identify the phenotype of distinct subpopulations of myeloid, erythroid and lymphoid cells in liquid suspension culture using differential expression of CD34 vs. CD71 in combination with specific lineage markers. Freshly isolated human CD34+ bone marrow cells were introduced into suspension culture and monitored over a 6-d period using 3-colour flow cytometry. This is the first demonstration that differential expression of CD34 vs. CD71 can be used to simultaneously monitor differentiation of multiple haematopoietic cell lineages in liquid suspension culture, facilitating the study of cytokine-, drug- or chemical-induced alterations in haematopoietic progenitor cell differentiation in vitro. 相似文献
70.
T.Wayne Schultz 《Ecotoxicology and environmental safety》1997,38(3):336-337