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At least 19 recordsLinked to original sources

PubMed1998

Trephining of nails: an overview of the commonest cause for trephining and the actual procedure of trephining.

Trephining of nails is a common and simple procedure undertaken by staff working within Accident and Emergency (A & E) departments or Minor Injuries Units across the country. This article aims to raise awareness about the commonest type of injury which requires this treatment and to explain the instant relief the procedure can give, how to undertake the procedure and the underlying complications to look out for.

Emergency Nursing↗

PubMed1993

Relative efficacy of bone marrow trephine biopsy sections as compared to trephine imprints and aspiration smears in routine hematological practice.

The relative efficacy of trephine sections, trephine imprints and aspiration smears in yielding diagnostic and additional information was compared in 767 sets of bone marrow samples. Trephine sections were diagnostic in significantly more cases as compared to trephine imprints and aspiration smears (P < 0.001). Additional information was obtained in 326 trephine sections which was not available from trephine imprints and aspiration smears. Significantly more number of trephine sections provided diagnosis in case of dry tap/scanty material, for assessment of lymphoma-tumour infiltration, cellularity, Perl's reaction, megakaryocyte density and proliferating cell lines in myeloproliferative disorders. Fibrosis of bone marrow, pattern of bone marrow involvement and topographical alterations were appreciable only on trephine sections. The differential counts done on trephine imprints and aspiration smears correlated well and cytomorphological characterisation of immature cells (blasts and promyelocytes) could be done on these two preparations. Although trephine sections provide maximum information, all three preparations were found complementing each other and should be evaluated simultaneously for complete bone marrow interpretation.

Biopsy↗

PubMed1985

[Corneal trephining for penetrating keratoplasty: study of the degree of precision and presentation of a new trephine].

The accuracy of corneal trephination with a Franceschetti trephine was investigated on Duragel contact lenses. A modified 7.3 mm Crock trephine (Brit. J. Ophthal. 62 [1978] 74-80) with a rotating diamond blade fitted was compared with the above-mentioned method. Trephination of Duragel lenses from the convex side yielded diameters either larger or smaller than 7 mm. With one exception trephination from the concave side produced disks smaller than 7 mm. All Duragel disks had an elliptical configuration after trephination with the Franceschetti trephine. Trephination with the modified Crock trephine yielded disks with diameters close to 7.3 mm in all meridians.

Corneal Transplantation↗

PubMed1993

Trephination with vacuum trephine in undercorrection of myopic epikeratoplasty.

For the treatment of undercorrection after myopic epikeratoplasty, early suture removal, scar revision, retrephination, replacement of lenticule and, recently, excimer laser photorefractive keratoplasty have been employed. We performed trephination with Hessburg-Barron vacuum trephine on 11 eyes of 11 patients whose post-epikeratoplasty myopic power was over -4.00 diopters for 3 consecutive months. Patients were followed up on post-trephination 1 month, 3 months and 6 months. The mean duration from epikeratoplasty to trephination was 14.27 months, the mean pre-trephination spherical equivalent was -8.50 D and the mean keratometric reading was 40.87 D. The mean reduction of spherical equivalent was -4.07, -5.99, -8.02 D at post-trephination 1, 3, 6 months, respectively. The mean keratometric reading was 37.60 diopters at 1 month and 41.53 diopters at 6 months. At 1 and 3 months, there were significant reductions of myopic power in refraction and keratometry (p < 0.01), but, at 6 months, regression to pre-trephination levels took place (p > 0.05). There was no change of uncorrected and best corrected visual acuity between baseline and post-trephination 6 months.

Adult↗

PubMed1998

Graft decentration in penetrating keratoplasty: nonmechanical trephination with the excimer laser (193 nm) versus the motor trephine.

BACKGROUND AND OBJECTIVE: Graft decentration is an obvious cause of postkeratoplasty astigmatism. The purpose of this study was to compare graft decentration after nonmechanical trephination with the excimer laser (193 nm) with that after mechanical motor-trephination in 50 consecutive patients with Fuchs' dystrophy and 50 patients with keratoconus. PATIENTS AND METHODS: To determine decentration in absolute values and clock hours, a postoperative slide was projected with a fixed magnification onto a pattern with circles corresponding to the trephination margin. Using a second transparent and movable pattern with concentric circles and ellipses, the authors measured the amount and direction of decentration relative to the limbus and to the pupil. In addition, the keratometric astigmatism and the refractive cylinder were assessed. In this prospective study, the patients were assigned randomly to either method of trephination. RESULTS: The decentration was significantly lower (P < .002) with excimer laser trephination (0.23 +/- 0.26 mm, relative to the limbus; 0.33 +/- 0.26 mm, relative to the pupil) than with mechanical trephination (0.58 +/- 0.23 mm, relative to the limbus [P < .01]; 0.64 +/- 0.24 mm, relative to the pupil [P < .005]). There was no significant difference between the results obtained in patients with Fuchs' dystrophy and those of patients with keratoconus. The preferred direction of decentration relative to the pupil was the lower quadrants. There was a mild correlation between net astigmatism and the absolute value of decentration. However, with sutures in place, there were no significant differences in the keratometric net astigmatism between mechanical and nonmechanical trephination (P = .16) or between Fuchs' dystrophy and keratoconus (P = .18). CONCLUSIONS: The results indicate that the amount of decentration can be reduced by specific techniques associated with nonmechanical trephination. This might have a favorable impact on the residual astigmatism after suture removal.

Adolescent↗

PubMed1988

Configuration of corneal trephine opening using five different trephines in human donor eyes.

In this laboratory study, we used five different corneal trephines on 60 fresh human donor eyes with controlled intraocular pressure to study the variation in the size and shape of the trephine openings. With all trephines, the average diameter of the button was larger than the diameter of the trephine at the epithelial side (mean difference, 0.21 mm; range, 0.06 to 0.35 mm) and the endothelial side (mean difference, 0.42 mm; range, 0.13 to 0.79 mm), presumably because the corneal tissue protruded into the trephine during cutting. The trephines that produced the most uniform opening were a nondisposable suction trephine and a freestanding disposable blade, but they caused some undercutting.

Aphakia↗

PubMed1996

Trephination and suturing of avascular meniscal tears: a clinical study of the trephination procedure.

On the basis of animal studies, an arthroscopic surgical system and procedure of trephination plus suturing were designed for clinical practice. The system consists of a trephine with a tooth-like tip, a guide, and an ordinary arthroscopic power handle. The guide introduces the trephine to the tear without abrading articular cartilage and controls the depth of the trephination. The power handle connected to a suction system provides an inside-out cut core of meniscal tissue. Thirty-six patients with meniscal tears underwent arthroscopic trephination plus suturing (group TS) and 28 patients had suturing alone (group S). The follow-up was 25 to 78 months. Two symptomatic retears have occurred in group TS and 7 symptomatic retears in group S. The symptomatic retear rate of group TS was significantly smaller than group S (P < .01). It is indicated that the patients treated with trephination have fewer symptoms and lower clinical failure rate. Arthroscopic trephination is a safe and easy procedure.

Adolescent↗

PubMed1999

Effect of trephination technique on the ultrastructure of corneal transplants: guided trephine system v posterior punch technique.

AIM: Different trephination methods may lead to differences in degree of tissue damage and endothelial cell loss, which both influence the outcome of penetrating keratoplasty. Light, transmission, and scanning electron microscopy were used to compare the ultrastructural appearance of the cut edges and the endothelial cell loss in 26 human corneal donor buttons obtained by trephination with the suction fixated guided trephine system (GTS) and with the free hand posterior punch technique (PPT). METHODS: Human corneas were stored between 5 and 14 days in Optisol. One cornea from each pair was used for each technique. Trephinations (7.5 mm) were performed either from the anterior direction with the GTS (n=13) or from the posterior direction with the PPT (n=13) using Pharmacia Superblade trephines. Light microscopy, transmission electron, and scanning electron microscopy were performed according to standard procedures. Widening of the cut edges and the extent of endothelial cell loss were measured at three different areas per corneal button and analysed statistically. RESULTS: In contrast with the PPT, the GTS trephine produced considerable fibrillar disorder at the cut edges of the corneal buttons. The distance to which the endothelial cell loss extended from the edges of the cuts was significantly (p<0. 001) lower for the GTS (42.2 (SD 50.8) microm from the edge) than for the PPT (109.3 (68.1) microm). Stromal widening at the edges (measured as percentage increase in stromal thickness, compared with the thickness of the central cornea) was observed with both techniques. However, the mean stromal widening produced by the GTS was significantly greater than that produced by PPT (106% (24%) v 69% (21%); p<0.002). CONCLUSION: Both trephination techniques produced only minor tissue damage. Nevertheless, there were distinct differences in the fine appearance of the cuts produced by the GTS and the PPT techniques. The extent of the fibrillar dislocation and stromal widening was greater at the edges of the GTS buttons. The GTS technique produced significantly less endothelial cell loss at the cut edges than did the free hand punching technique, PPT.

Aged↗

PubMed1987

An experimental comparison of three methods for trephination of the cornea and the consequent variations in the configurations of the trephine openings.

We used the pig eye as an experimental model. The corneas of 51 whole eyes were trephined in a laboratory setting, using three different techniques to compare the variations in the trephine openings. Since it is difficult to assess the diameter of the hole created by trephination, we measured both the epithelial and endothelial diameters, as well as the angle between the epithelial surface and the cut of the excised corneal button, since these dimensions reflect the true shape of the hole. Trephination with either a free-standing trephine blade without a handle or with a motor-driven instrument gave the same results. However, our findings showed that the results obtained using a trephine in a holder--as is commonly used in clinical practice--were statistically significantly inferior.

Animals↗

PubMed2004

Q-switched erbium:YAG laser corneal trephination: thermal damage in corneal stroma and cut regularity of nonmechanical Q-switched erbium:YAG laser corneal trephination for penetrating keratoplasty.

PURPOSE: To assess stromal thermal damage and cut regularity induced by nonmechanical Q-switched Er:YAG laser corneal trephination for penetrating keratoplasty. METHODS: Corneal trephination was performed in 80 enucleated porcine eyes by Q-switched (2.94-microm) Er:YAG laser, along with donor and recipient masks made of metal or ceramic. All combinations of 0.65- or 0.96-mm spot diameter and 45- or 50-mJ/pulse energy setting were used with each of the masks at a 5-Hz repetition rate. Corneas were processed for histologic examinations. Stromal thermal damage was quantified on PAS-stained slides, and cut regularity was assessed semiquantitatively on a scale from 0 (regular) to 3 (highly irregular). Transmission electron microscopy and scanning electron microscopy were performed on selected specimens. RESULTS: The least thermal damage (mean +/- SD = 6.2 +/- 0.7 microm) was found in the donor ceramic group with 50-mJ/pulse energy and 0.65-mm spot diameter, while the best regularity of the cut (1.2 +/- 0.4) was found in the donor ceramic group with 45-mJ pulse energy and 0.65-mm spot diameter. Thermal damage was less pronounced in donor than in recipient corneas (P < 0.01). Smaller spot diameter (0.65 mm) led to less thermal damage (P < 0.01) than the use of a 0.96-mm spot diameter. The differences in thermal damage between ceramic and metal masks were minimal. CONCLUSIONS: After Q-switched Er:YAG laser corneal trephination for nonmechanical penetrating keratoplasty, reproducible high cut regularity and low concomitant thermal damage were observed. This is an encouraging finding in the search for a nonmechanical trephine for penetrating keratoplasty combining high precision and low cost.

Animals↗

PubMed1981

Results and complications of limbal trephination and subscleral trephination (trabeculectomy).

Limbal trephinations on 395 eyes were followed postoperatively for six months to 19 years. Excellent results were obtained in patients over the age of 35, particularly those in the 50 and older age group, with chronic open-angle and chronic angle-closure glaucoma. Results were poor in younger age groups and in those with secondary glaucoma, particularly where it was associated with inflammatory disease. A review of 78 limbal trephinations in individuals over 55 and 77 trabeculectomies (67 under age 55 and ten over age 55) indicated that in younger age groups the overall results were nearly the same with trabeculectomies as with limbal trephination but the subscleral operation is probably safer, especially in younger people with longer life expectancy, and permits freer use of contact lenses postoperatively.

Adolescent↗

PubMed1999

Free-running erbium:YAG laser for nonmechanical trephination in penetrating keratoplasty: first results of experimental trephination of human donor corneas.

BACKGROUND: A study was carried out to evaluate the potential suitability of a free-running erbium:YAG 2.94-microm laser for trephination of human corneas in penetrating keratoplasty. METHODS: Two human donor corneas were placed in an artificial anterior chamber and moved with an automated rotation device (one rotation per minute). An erbium:YAG laser beam (pulse duration 400 micros, repetition rate 2/s, energy density 2.5 and 15.0 J/cm(2)) was focused on the outer edge of a round ceramic mask placed on the human donor corneas for ablation of tissue. RESULTS: With a fluence of 15.0 J/cm(2), perforation was achieved after 500 pulses. Perpendicular central cut edges with mild stromal ridges and, by light microscopy, a 12 to 45-microm area of stromal thermal effects and focal endothelial changes up to 200 microm central to trephination were observed. CONCLUSIONS: The erbium:YAG laser could be a promising "low-cost alternative" to the excimer laser for nonmechanical trephination in penetrating keratoplasty. Further studies will have to focus on reduction of thermal damage and on wound healing.

Animals↗

PubMed1987

Distribution of IgA1 and IgA2 subclasses in normal bone marrow trephines and in trephines infiltrated by IgA producing multiple myeloma.

A series of 20 bone marrow trephines biopsy and necropsy specimens were strained for IgA1 and IgA2 activity, together with total IgA, by means of an indirect immunoperoxidase technique using murine monoclonal antibodies applied to paraffin sections. The specimens showed normal histology and had been taken from patients not known to be suffering from haematological or related systemic disease. The IgA1, IgA2, and total IgA containing cells were counted and expressed as a percentage of all nucleate cells in the marrow cavities. Remarkably constant percentages of and ratios between these cell types were found. The same was true for a further 10 trephines taken from patients undergoing staging procedures for epithelial malignancies, where the marrow histology was normal. The pooled mean percentage of IgA1 containing cells from both groups was 1.18% of all cells, that for IgA2 containing cells 0.18%, and for total IgA positive cells 1.41%. In addition, 12 trephines containing known IgA producing myeloma were examined. Of these, 11 contained IgA1, the remainder contained IgA2 subclass.

Adolescent↗

PubMed1999

How reliable is histologic examination of bone marrow trephine biopsy specimens for the staging of non-Hodgkin lymphoma? A study of hairy cell leukemia and mantle cell lymphoma involvement of the bone marrow trephine specimen by histologic, immunohistochemical, and polymerase chain reaction techniques.

Analysis of non-Hodgkin lymphoma (NHL) involvement of bone marrow trephine biopsy specimens by morphologic features and immunohistochemistry is often difficult, and the criteria for involvement are ill defined. We compared the morphologic and immunohistochemical analysis of B-cell NHL involvement with immunoglobulin heavy chain gene (IgH) rearrangement analysis by polymerase chain reaction (PCR) amplification of the complementarity determining region 3 (CDR3) in bone marrow biopsy specimens from patients with mantle cell lymphoma (n = 53) or hairy cell leukemia (n = 71). By combing morphologic features and phenotype, 54 specimens were considered positive, 62 negative, and 8 inconclusive. PCR analysis showed clonal IgH rearrangements in 46 positive and 6 inconclusive specimens. No clonal IgH rearrangements were present in 61 negative specimens. The 1 false-positive and most false-negative PCR results were likely due to sampling error or DNA degradation of the fixed tissues. In most cases, bone marrow involvement by NHL can be identified by histologic and immunohistochemical examination. Furthermore, clonality of the B-cell population can be detected by amplification of the IgH CDR3 on DNA extracted from bone marrow trephine biopsy sections, which can be helpful in cases diagnosed as inconclusive.

Bone Marrow Examination↗

PubMed1975