Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Trephining”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43Linked to original sources
PubMed1982

[Role of aspiration and trephine biopsies in the diagnosis of prostatic cancer].

The predictive value of aspiration and trepan biopsy is analysed in 247 cases of prostatic cancer. The diagnostic value of trepan biopsy is 90.1%; it is not determined by the degree of tumor differentiation. The value of aspiration biopsy varies with different degree of differentiation; it is 42.1% for well-differentiated cancer, 81.2%--for moderately- and 97.4%--for poorly-differentiated tumors. Aspiration biopsy is a safe procedure, while trepan biopsy may be followed by severe complications.

Biopsy↗
PubMedDate not supplied

[Skeletal mineralization in cattle in 1960 and 1990 based on trephine biopsy data].

Skeleton of cows living in the zone of Kiev Polesye (Woodlands), a comparatively safe area of radioactive pollution, as compared with 1960, was found to have practically the same content of calcium, phosphorus, sodium, copper; the content of potassium decreased, that of zinc was greater; the increased content of magnesium, manganese, strontium and lead was statistically valid. An increased incorporation of magnesium, zinc and manganese and a decreased fixation of iron and potassium were mainly due to changed conditions of feeding and maintenance of the animals, while the increased content of strontium and lead was a result of the increased pollution of the environment.

Animals↗
PubMed1996

The value of percutaneous transpedicular vertebral bone biopsies for histologic examination. Results of an experimental histopathologic study comparing two biopsy needles.

STUDY DESIGN: A 3.5-mm trephine was designed to overcome difficulties encountered in the histologic evaluation of vertebral bone samples obtained with a 2-mm trephine. OBJECTIVES: To compare the 3.5-mm trephine with the 2-mm trephine. SUMMARY OF BACKGROUND DATA: A review of results obtained with a 2-mm trephine showed that histologic examination of vertebral bone cores was disturbed by artifacts in 32 of 70 cases (46%). Although tissue diagnosis was possible from 61 samples, only 36 (51%) bone cores yielded a secure diagnosis. METHODS: Transpedicular bone cores were obtained from the bodies of 54 fresh cadaver vertebrae with both trephines. In each vertebra, the 2-mm trephine was used on one side, and the 3.5-mm trephine was used on the other side. Longitudinal sections were prepared and examined macroscopically for length and breakages and microscopically for trabeculae, marrow, and artifacts. Each sample was graded for its value for histologic examination. RESULTS: Significant differences were found between the two trephines for all criteria evaluated. Of 54 samples taken with the 2-mm trephine, 13 (24%) were graded "good," compared with 45 (83%) from the 3.5-mm trephine. Twelve (22%) "bad" samples were taken from the 2-mm trephine compared with three (6%) "bad" samples taken from the 3.5-mm trephine. CONCLUSIONS: The 2-mm trephine does not provide suitable bone cores for histologic examination, whereas samples obtained with the 3.5-mm trephine are suitable.

Aged↗
PubMed2004

Mechanical stability of microkeratome-assisted intracorneal keratoprosthesis implantation.

OBJECTIVE: To develop a laboratory model to study intracorneal keratoprosthesis implantation. METHODS: A combination microkeratome and artificial anterior chamber system was used to create a hinged lamellar keratectomy on 13 human corneas. After reflecting the flap, the posterior stroma was trephined at either 2.5 or 3.0 mm. A model keratoprosthesis was positioned in the bed. The flap was sutured closed. Intrachamber pressure was increased, and wound leak pressure was recorded. The anterior corneal lamella was trephined at either 3.0 or 3.5 mm to expose the keratoprosthesis. Leak pressure was again determined. RESULTS: After keratoprosthesis placement and prior to anterior trephination, all 13 corneas were watertight at maximum attainable intrachamber pressures. With posterior/anterior trephination combinations of 2.5/3.0 mm, 2.5/3.5 mm, or 3.0/3.5 mm, mean +/- SD wound leak pressure occurred at 95 +/- 12 mm Hg, 32 +/- 7 mm Hg, or 59 +/- 12 mm Hg, respectively (P<.01). CONCLUSIONS: With a posterior trephination of 2.5 mm, there is significant keratoprosthesis-cornea interface destabilization between a 3.0- and 3.5-mm anterior trephination. For an anterior trephination of 3.5 mm, interface destabilization improves by increasing the posterior trephination to 3.0 mm. CLINICAL RELEVANCE: An intracorneal keratoprosthesis may be implanted using microkeratome assistance. Our laboratory model provides a useful method for examining a range of posterior and anterior trephination diameters and their effects on the mechanical stability of intracorneal keratoprosthesis placement.

Adult↗
PubMed1996

[Regularity of corneal topography after penetrating keratoplasty--comparison between non-mechanical (excimer laser 193 nm) and mechanical trepanation].

BACKGROUND: "Vertical tilt" of the graft caused by incongruent cut angles, "horizontal torsion" caused by a asymmetric suturing and decentration of the wound seem to be the most important reasons for high and/or irregular postoperative astigmatism and deterioration of visual outcome after penetrating keratoplasty. We studied the time course of qualitative and quantitative topographic criteria after nonmechanical and mechanical trephination in correlation with visual outcome. PATIENTS AND METHODS: Fifty patients each (30 keratconus, 20 Fuchs' dystrophies) underwent nonmechanical trephination (excimer laser MEL60, Aesculap-Meditec, Heroldsberg) and mechanical motor-trephination in penetrating keratoplasty. All procedures (7.5 mm trephination diameter in Fuchs, 8.0 mm in keratoconus, double-running 10-0 nylon suture) were done by one surgeon. Pre-, intra- and postoperative treatment were identical. At the follow-up examinations, the keratometric astigmatism, qualitative and quantitative criteria of the automatic videokeratography, visual acuity and refraction were assessed. In addition, vector-corrected astigmatism (Jaffe-model) was evaluated in the postoperative time course, particularly after suture removal. RESULTS: After a mean follow-up of 1.1 +/- 0.8 years, keratometric net astigmatism was 4.0 and 4.2 diopters after nonmechanical and mechanical trephination. Corneal topography analysis showed a higher orthogonality of the bowtie shape and less asymmetry between opposite hemimeridians. Vector-corrected changes of corneal astigmatism were less after complete suture removal in nonmechanical trephination. After nonmechanical trephination, visual acuity was 2 decimal lines better. DISCUSSION: Nonmechanical trephination with the excimer laser 193 nm has the potential to improve the visual outcome by creating smooth and congruent cut edges parallel to the optical axis and the application of "orientation teeth". Since corneal net astigmatism does not differ significantly, a higher regularity of corneal topography after excimer laser trephination is supposed to be a main reason for this finding.

Adolescent↗