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A new surgical curved drill system that drills curved holes into bone is presented, along with several examples of its use in foot and ankle surgery. The technical information involving soft tissue fixation, wiring, or suturing around a bone bridge, by drilling a curved tunnel for tendon, capsule, and ligament reconstruction is also reviewed.
OBJECTIVES: A cost-effectiveness analysis was conducted comparing diagnostic strategies for determining the HER2 status of invasive breast carcinomas, as an indication for trastuzumab at metastatic relapse. METHODS: A decision tree compared five strategies distinguished by (i) the use of immunohistochemical (IHC) and/or fluorescent in situ hybridization (FISH) techniques, and (ii) the test schedule (at initial diagnosis or metastatic relapse). Most cost and effectiveness data came from a French multicentric study of 2,045 patients from eight hospitals. We were not able to select final criteria for trastuzumab effectiveness, because published data rely on IHC techniques not used in France (i.e., HercepTest). We, therefore, selected two intermediate criteria for inappropriate treatment at relapse, that is, patients with HER2-amplified tumors not receiving trastuzumab (Criterion 1) and HER2-nonamplified tumors improperly treated with trastuzumab (Criterion 2). Sensitivity analyses were then performed to assess the robustness of the results to (i) discount rate, (ii) cost of FISH, and (iii) tissue fixation technique. RESULTS: The strategy using IHC at diagnosis was dominated by the four other strategies. Among these approaches, the only efficient strategy for both criteria was IHC used alone at metastatic relapse; strategies using FISH, or IHC followed by FISH on IHC2+ cases were efficient for Criterion 1, whereas IHC followed by FISH on IHC2+ and 3+ cases was efficient for Criterion 2. CONCLUSIONS: Determining HER2 status at diagnosis, as an indication for trastuzumab at metastatic relapse, incurs substantial incremental costs, which do not appear to be justified. No other strategy can be excluded at first.
In this study, the distributions of calcitonin gene-related peptide, neuropeptide Y, and alpha-atrial natriuretic peptide 1-28 immunoreactivity, were investigated within different regions of the guinea pig heart by utilising two different methods of tissue fixation for the immunocytochemistry. The results were compared with data obtained through radioimmunoassays. We observed similar concentrations and distributions of alpha-atrial natriuretic peptide in the right atrium, with results of radioimmunoassay and immunocytochemistry, but there were no myocytes containing alpha-atrial natriuretic peptide in the left atrium or ventricles with immunocytochemistry as opposed to radioimmunoassay. The immunoreaction obtained for neuropeptide Y was more intense in the right ventricle than left. Calcitonin gene-related peptide nerve fibres were about twice as abundant in the left atrium than in the right.
Microwave coagulation therapy (MCT) has been applied to small hepatic carcinomas. To clarify the sequential changes in histology and the viability of the microwave-irradiated tissue, we examined irradiated normal rat liver with enzyme histochemistry for acid phosphatase (AcP). In the samples immediately after irradiation, the margin of the irradiated region was indistinct in H&E stain, while AcP enzyme histochemistry disclosed well-demarcated distinct zones: an inner zone adjacent to the electrode without AcP activity and a surrounding outer zone with attenuated enzyme activity. In the inner zone, the nuclear staining with hematoxylin persisted for at least one month, whereas that in the outer zone disappeared 24 hr after irradiation and was accompanied by neutrophilic infiltration and then replaced by granulation tissue. Our results indicated that microwave irradiation caused tissue fixation in the inner zone and coagulative necrosis in the outer zone. Because microwave-fixed cells retained their morphology well, they appeared very similar to normal cells in H&E-stained section. Enzyme histochemistry may be useful for assessment of cellular viability after microwave irradiation, by enabling us to distinguish fixed cells from viable cells.
The use of the Escherichia coli enzyme beta-glucuronidase (GUS) as a reporter in gene expression studies is limited due to loss of activity during tissue fixation by glutaraldehyde or formaldehyde. We have directed the evolution of a GUS variant that is significantly more resistant to both glutaraldehyde and formaldehyde than the wild-type enzyme. A variant with eight amino acid changes was isolated after three rounds of mutation, DNA shuffling, and screening. Surprisingly, although glutaraldehyde is known to modify and cross-link free amines, only one lysine residue was mutated. Instead, amino acid changes generally occurred near conserved lysines, implying that the surface chemistry of the enzyme was selected to either accept or avoid glutaraldehyde modifications that would normally have inhibited function. We have shown that the GUS variant can be used to trace cell lineages in Xenopus embryos under standard fixation conditions, allowing double staining when used in conjunction with other reporters.
Four albumin conjugates of oestradiol. Labelled with fluorescein or peroxidase to permit visualization under light or fluorescence microscopy, were synthesized. These were used to examine the feasibility of identifying oestrogen binding in frozen section by two published histochemical techniques. In a variety of experimental tissues and human breast cancers, binding of the oestrogen conjugates was demonstrable, but it appeared nonspecific (i.e., rarely displaceable by competitor) and unrelated to oestrogen receptor (RE) status of the tissue as determined biochemically by assay with dextran-coated charcoal. Investigation of the fate of the RE through the various steps of a histochemical assay, demonstrated major losses of RE from unfixed tissue or after tissue fixation. The RE also exhibited a 10-50-fold poorer affinity for the conjugates synthesized than for oestradiol-17 beta and, at the concentrations of conjugate routinely used in histochemical assays, it seems likely that considerable nonspecific binding takes place. These factors may combine to make it (1) difficult to implement such histochemical assays and (2) unlikely that the RE is being detected.
Purpose Imaging vitreous is a quest to view what is, by design, invisible. This treatise will review significant historical aspects, past and present imaging methodologies, and imaging techniques that are currently in development for future research and clinical applications. Methods Classic and modern histologic techniques, dark-field slit microscopy, clinical slit lamp biomicroscopy, standard and scanning laser ophthalmoscopy, ultrasonography, optical coherence tomography, magnetic resonance and raman spectroscopy, and dynamic light scattering methodologies are presented. Results The best available histologic techniques for imaging vitreous are those that avoid rapid dehydration of vitreous specimens. Dark-field slit microscopy enables in vitro imaging without dehydration or tissue fixatives. Optical coherence tomography enables better in vivo visualization of the vitreo-retinal interface than scanning laser ophthalmoscopy and ultrasonography but does not image the vitreous body. Dynamic light scattering can determine the average sizes of vitreous macromolecules within the vitreous body as well as possibly image the posterior vitreous cortex once detached, while Raman spectroscopy can detect altered vitreous molecules, such as glycated collagen and other proteins in diabetic vitreopathy. Conclusions The inability to adequately image vitreous hinders a more complete understanding of its normal structure and how this changes in aging and disease. The combined use of more than one technique could provide better imaging of vitreous for future investigational and clinical purposes.
In major depression, decreased hippocampal volume has been attributed to hypercortisolemia, a frequent sign of the disorder, because in animals an excess of corticosteroids has led to dendritic atrophy, astrogliosis and loss of neurons in this brain region. The present study is the first to investigate the structural integrity of the human hippocampus in major depression and following glucocorticoid treatment. Post-mortem hippocampal tissue from 15 patients who had had major depression or bipolar affective disorder, 10 patients who had been treated with glucocorticoids and 16 controls was assessed using haematoxylin-eosin, Nissl and Bodian staining. The patterns of reactive astrogliosis (glial fibrillary acidic protein, GFAP), synaptic density (synaptophysin), synaptic reorganization (growth-associated protein B-50) and early signs of Alzheimer's disease (Alz-50) were examined immunocytochemically. Multivariate analysis, with the patients' age, tissue fixation time and postmortem delay as covariates, was performed. There was no evidence of neuronal cell loss or other major morphological alterations in any of the groups, nor was there a significant change in the distribution pattern of synaptophysin or Alz-50. Changes in B-50 and GFAP staining were observed in the steroid-treated and depressed patients in areas CA1 and CA2 only. The human hippocampus in major depression and after glucocorticoid treatment does not reveal any major morphological changes or signs of neuronal cell death, but does show subtle alterations in B-50 and GFAP expression in selected parts of the pyramidal cell layer.
AIM: To gather information on root-canal treatment carried out by dentists working in Flanders (Belgium). METHODOLOGY: A questionnaire reported in a previous study was also used to gather information on canal medicaments, canal filling, and in decision making for referrals and treatment of apical periodontitis. RESULTS: Calcium hydroxide as an interappointment dressing was used by 69.7% of the respondents. Approximately one-third of the respondents did not use any intracanal medicament. Caustic products used for pulp tissue fixation were used by 66.8% of the respondents. Cavit (48.2%) and glass-ionomer (31.3%) were the temporary coronal-filling materials used most often, followed by zinc oxide-eugenol and IRM(R). Cold lateral condensation of gutta-percha was the filling technique most used by the respondents (65.8%). Single-cone gutta-percha placement (16%), paste techniques (4.9%) and silver points (3.9%) were still used. Resin-based sealers were used most often (88.6%). Paraformaldehyde containing sealers such as Endomethasone and N2 were used infrequently. Approximately half of the practitioners were satisfied with their canal-filling technique, others felt that they could do better (43.0%); 0.7% were not satisfied. In cases with apical periodontitis, the size of periapical lesions and/or the presence of a root filling influenced the choice of endodontic treatment. The most common reasons for referral of endodontic cases were: retrieval of silver points, surgery, and post removal. CONCLUSIONS: The results of this study indicate that techniques and methods used for canal medication and canal filling were acceptable for the majority of the respondents. Re-treatment was underestimated as a treatment option.
The microwave oven has many potential applications, ranging from tissue fixation to staining for light and electron microscopy. This study was planned to speed up the staining of ultrathin sections. The first set of grids was stained conventionally with uranyl acetate and Reynold's lead citrate solutions. The other grids were stained with the same solutions by microwave irradiation. The electron micrographs of grids stained using the microwave technique were as satisfactory as the grids stained conventionally. Microwave-treated grids demonstrated more uniform staining and less precipitate. The use of a microwave oven shortened staining time by approximately 38 min.
Glial fibrillary acidic protein (GFAP) is an established marker of retinal glia and has been shown to be modulated by several cytokines and retinal pathology. The influence of a number of factors, including post-mortem delay, storage duration and retinal pathology, on the distribution and morphology of macroglia and GFAP antigenicity was examined in human retina. The effects of these parameters on GFAP expression were estimated using immunohistochemistry, confocal microscopy and image analysis. Changes in expression of antigenicity were analysed in human retinal cryosections at three levels: constitutive,aberrant and total. The results indicated that short-term and long-term storage duration had no significant effect on GFAP immunoreactivity at all three levels of expression (P > 0.2).However, a significant increase in GFAP immunoreactivity and distribution at all three levels of expression was associated with prolonged post-mortem delay (> 30 h) (P < 0.05). This study highlights the importance of rigorous matching of post-mortem delay between control specimens in histological studies of human retinae. The study further demonstrates the utility of Eye Bank retinae fixed and stored in 2% paraformaldehyde, provided that appropriate controls are applied.
We developed a multiparameter flow cytometric technique for the simultaneous measurement of cellular DNA content and c-erbB-2 or epidermal growth factor receptor (EGFR) expression. The method provides a high resolution of DNA content and well preserved c-erbB-2 and EGFR immunostaining under saturated antibody conditions, allowing good control for background fluorescence and satisfactory cell morphology. Four different protocols for the short-term preservation of cells used for multiparameter flow cytometric assay of EGFR and c-erbB-2 were assessed in cell suspensions prepared by mechanical disaggregation in 10 gynecologic tumors. The protocols at 4 degrees C were: storage in 50% methanol, and storage in buffer after formalin fixation. Tissues were also cryopreserved as cell suspensions and tissue blocks. When the oncoprotein expression and DNA histograms were compared with those in fresh suspensions, cryopreservation was found to be the best method: oncoprotein expression was well preserved and there was a good correlation between oncoprotein expression and the quality of the DNA histograms. The currently developed methods for cell preservation make the technique generally available for clinical cancer studies.
UNLABELLED: Cancer of the buccal mucosa is an uncommon and aggressive neoplasm of the oral cavity. Less than 2% of patients treated for cancer of the oral cavity at Roswell Park Cancer Institute (RPCI) from 1971 to 1997 had primary buccal cancers. Because the majority of these patients did not undergo any adjuvant treatment, this group provided us with the opportunity to assess the relationship between margin status and local recurrence for both small (T1-T2) and large (T3-T4) tumors treated with surgery alone. MATERIALS AND METHODS: The RPCI tumor registry database reported 104 patients who were treated for buccal carcinoma. A retrospective chart review identified 27 patients who met our criteria for a buccal mucosal primary tumor (epicenter of the mass in the buccal mucosa). There were 13 men and 14 women, ranging in age from 34 to 94 years (mean, 75). Data were collected regarding patient demographics, presenting symptoms, stage, treatment received, and outcome. RESULTS: All patients underwent surgical resection of their primary lesion; 21 (75%) had T1 or T2 tumors. The rate of local recurrence was 56% for the group as a whole. Patients with close or positive margins had a 66% local failure rate as compared with 52% when surgical margins were negative (greater than or equal to 5 mm from the resection margin after tissue fixation; P = ns). Among those in whom negative margins were achieved, patients with T1-T2 disease had a 40% local failure rate with surgical resection alone. CONCLUSIONS: Local excision of T1 and T2 buccal mucosa cancers with pathologically negative margins had a high rate of local recurrence in our series. Low T-stage and negative margins are not adequate predictors of local control. Even early buccal tumors may benefit from adjuvant therapy to enhance local control.
AIMS: Sentinel Node Biopsy (SNB) is considered an accurate method of detecting axillary lymph node status in patients with small breast cancer. Combined with an accurate and rapid histopathology tool, it could spare this group of patients unnecessary Axillary Node Clearance (ANC) with its associated hazards. Intraoperative examination of SNB for cancer cells has been investigated using both Frozen Sections (FS) and Imprint Cytology (IC) stained with different stains. This study is devoted to establish a reliable and rapid protocol for immunostaining of touch imprints from SNB. METHODS: We investigated two different EPOS (Enhanced Polymer One-Step staining--DAKO) anticytokeratin antibodies, five different tissue fixatives and different incubation periods and temperatures with both positive and negative controls. RESULTS: We have developed a protocol, which produced good and consistent immunostaining of touch imprints. The initial results using this protocol are concordant with those of permanent Haematoxylin and Eosin (H&E) sections. CONCLUSIONS: We propose this protocol for rapid immunostaining of touch imprints of SNB.
PURPOSE: The purpose of this study was to evaluate the outcome of patients who underwent arthroscopic repair of anterosuperior rotator cuff tears. The null hypothesis, that there was no difference between preoperative scores and postoperative scores, was tested statistically. TYPE OF STUDY: A cohort study. METHODS: The preoperative and postoperative status of patients with anterosuperior rotator cuff tears was analyzed using the Constant score, American Shoulder and Elbow Society Index (ASES Index), a visual analog pain scale (VAS), a single question of percent function compared with the opposite unaffected extremity, and a single question reflecting satisfaction, "would you undergo the surgery and the postoperative rehabilitation to achieve the result you have today." There were also 2 groups compared: 1 that had a "tac" used for repair of the subscapularis tendon, and the other that used a "tie" technique for subscapularis repair. All supraspinatus tendon tears were complete and were repaired using a soft-tissue fixation device. RESULTS: There was a statistically significant difference for all outcome measures except for the objective Constant score of the tie group, P =.58. Follow-up was 2 to 4 years. There were no differences based on sex or type of fixation device used for repair of the subscapularis tendon. There were no reruptures, clinically. CONCLUSIONS: The arthroscopic repair of anterosuperior rotator cuff tears provides reliable expectation for improvement in function, decreases in pain, decreases in clinical findings of biceps subluxation and inflammation, improvement in shoulder scores, and the improvement of clinical findings of subscapularis insufficiency.
Over the past 5 years, robotic systems that combine advanced endoscopic imaging with computer-enhanced instrument control have been used for both coronary revascularization and intracardiac procedures in adults. In addition, endoscope positioning systems and articulated instruments with a robotic wrist mechanism have further expanded the potential applications for robotics in cardiac surgery. In pediatric cardiac surgery, potential applications can be divided into simple scope manipulation versus the use of 3-dimensional imaging and a robotic wrist for dissection and reconstruction. A voice-controlled robotic arm for scope manipulation can facilitate current pediatric thoracoscopic procedures such as ligation of patent ductus arteriosus and division of vascular rings. By using an advanced imaging system along with a robotic wrist, more complex extracardiac and even intracardiac procedures can be performed in children. Examples include coarctation repair, septal defect repair, and mitral or tricuspid valvuloplasty. Furthermore, with adequate intracardiac imaging, a robot-assisted off-pump approach to intracardiac pathology is conceivable. New real-time 3-dimensional echocardiography now offers sufficient resolution to enable such procedures, while the addition of instrument tracking, haptic feedback, and novel tissue fixation devices can facilitate safe and reliable intracardiac repair without extracorporeal circulation.
In a patient with aneurysms of the sinuses of Valsalva a stentless porcine bioprosthesis was implanted with excellent hemodynamic and clinical short-term results. The implantation technique was similar to the technique used for the implantation of a composite graft. The postoperative study revealed a pressure gradient of 7 mmHg between the left ventricle and aorta and no regurgitation. Although the implantation of a porcine aortic root including a part of the ascending aorta without any artificial stenting material is feasible, one should be aware of the specific technical difficulties due to the increased rigidity of the fixated tissue. To our knowledge this is the first report of an implantation of a stentless aortic root porcine bioprosthesis for the treatment of aneurysms of the sinuses of Valsalva.
To remove an infected pacemaker system in order to control the infection is often difficult when there is extensive connective-tissue fixation of the electrode. Forced manual extraction may lead to severe complications. For this reason, operative removal, in certain circumstances involving cardiotomy under extracorporeal circulation, has been practised. An alternative is continuous traction in which the probe is attached peripherally and by continuous traction removed from its cardiac attachment. Nine patients have been treated successfully by this method. In eight the electrode was removed within 1-10 days without significant complications. In one instance the electrode-catheter tore within the superior vena cava after 18 days of continuous traction; the remaining catheter, about 12 cm long, was removed with a sling catheter.