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PubMed1987

[Detection of residual cells contaminating the bone marrow in neuroblastoma. Apropos of 80 bone marrow evaluations].

Eighty bone marrow studies (each including 4 aspirates and 4 trephine biopsies) were performed in 37 children with stage IV neuroblastoma to assess the most accurate means for detection of invasion by neuroblastoma cells. Among 38 abnormal results, only trephine biopsy(ies) were found positive in 24 cases (63%), only aspirate(s) in 5 cases (13%), and both in 9 cases (24%). In 37% of abnormal results, only 1 of the 8 tests performed was found positive. No benefit was obtained from either associated touch imprints of iliac biopsies (67 investigations), or exploration of extra-iliac sites (66 sternums, 53 tibias). Two monoclonal antibodies, claimed to be specific for detection of neuroblastoma cells in bone marrow, were used in 56 investigations; they could detect minimal residual disease in some cases, but they were unreliable when no staining was obtained if initial phenotype of neuroblastoma had not been assessed, or when few isolated cells were observed. Prospective studies using immunocytology and immunohistology are thus warranted.

Antibodies, Monoclonal↗
PubMed1979

Astigmatic considerations in corneal graft.

Some fictions about astigmatism should be dispelled: 1) Sutures determine astigmatism. They do not. 2) The size of the graft is contributory to astigmatism. It is not contributory. 3) Anterior or posterior cutting of the graft makes no difference. It does make a difference. 4) Same size trephine can be used to cut graft and recipient opening. Not when graft is cut from posterior surface or significant flattening will result. 5) A small cutting error is of no consequence. A small cutting error can cause a great deal of astigmatism. Tissue factors are paramount. Sutures must maintain wound apposition primarily. Posterior cutting requires a larger diameter trephine. A one-half-mm cutting error can cause an astigmatism of five diopters. Excessive corneal astigmatism, when it does occur, can be controlled by corneal wedge resection. The surgical keratometer identifies and limits surgical and suture-induced errors. Success in microsurgical keratoplasty can no longer be defined only as a clear graft. It must include also minimal or no residual optical error.

Astigmatism↗
PubMed1979

Choroid plexus carcinoma. Case report.

Plexus-chorioideus carcinomata or malignant plexus papillomas are very rare; only few cases have been described in the literature. A further observation is added now. In a 13-year-old girl, signs of brain pressure occured two weeks before admission to a hospital. Scintigraphy and vertebral angiography showed a process in the atrium of the right lateral ventricle which was removed by temporo-parietal trephination. The tumour had the size of an apricot and a reddish colouration, it proceeded from the plexus. After-irradiation with 5 000 rad. Six years after the operation, signs of brain pressure appeared again. Neuroradiologically the process was located in the right cerebellar hemisphere. After trephination of the cerebellum, the largely vascularised tumour, which appeared to originate from the tela choroidea of the 4th ventricle, could be removed. The further course was without pathological findings. Histologically, the typical criteria were found: Invasion of surrounding brain structures, loss of the regular papillary structure, malignisation of the cells and originating from the plexus choroideus.

Adolescent↗
PubMed1977

[Clinical results of the goniothrephining with scleral flap (author's transl)].

During 1971-1976 407 goniotrephinings e.g. "Elliot with scleral flap", were performed at the Univ. Eye Hospital Münster. In a follow-up study of 306 operated cases we found 81% primary glaucoma (62.7% simple glaucoma, 18.3% chronic congestive glaucoma) and 19% secondary glaucoma. In 77% of the operated cases the anterior chamber was restored within the first postoperative day. Gonioscopically in 85% the trephining hole was placed within the trabecular meshwork. Nevertheless, this position of the hole had no decisive influence on the later filtration. Postoperatively 2/3 of cases developed a characteristic flat filtering bleb. In 90.4% of the eyes the postoperative IOP was within normal limits. Postoperative follow-up of the visual acuity remained within the limits of age deterioration. Concerning the secondary glaucoma, the pigmentary glaucoma, the traumatic glaucoma and the glaucoma after uveitis, had good results. The results in cases of buphthalmos and hemorrhagic glaucoma were worse. The advantages of goniotrephining are the rapid restoring of the anterior chamber, the protection of the trephining hole by the scleral flap as well as the well "protected" flat and infections-resisting bleb.

Anterior Chamber↗
PubMed1984

Combined use of sodium hyaluronate and tissue adhesive in penetrating keratoplasty of corneal perforations.

A new technique which allows the use of a guarded trephine in penetrating keratoplasty for corneal perforation is described. It involves the combined use of cyanoacrylate adhesive and sodium hyaluronate and allows a normotensive eye to be obtained prior to trephination. Five cases in which this technique was used are described. A better tectonic result can be obtained and visual rehabilitation may be more readily achieved without performing a secondary procedure.

Aged↗
PubMed1984

Conjunctival epithelial wound healing.

In vivo conjunctival epithelial healing in albino rabbits was investigated by light microscopy following both n-heptanol and trephined conjunctival wounding. Reepithelialization occurred faster following n-heptanol treatment (3 days) versus trephination (6-7 days). No goblet cells were present in the migrating epithelium during reepithelialization. After 1 day of wounding, goblet cells disappeared several millimeters peripheral to the wound margin in both types of wounds. Goblet cells first reappeared peripherally 1 week after wounding before they appeared in the central wound area. These observations indicate that a large area of conjunctival epithelium surrounding a wound is involved with repair of that wound. Since the goblet cell content of conjunctival epithelium appears to change as a result of the stresses of epithelial repair, the goblet cell population may reflect the presence of reparative or proliferative processes in the ocular surface.

Animals↗
PubMed1983

The surgical treatment of chondromalacia of the patella.

In a retrospective review of 184 knees treated for surgically diagnosed chondromalacia of the patella, the average follow-up period was 3.9 years. The treatment rendered included trephine and drilling in 71 knees, facetectomy in 57 knees, shaving in 35 knees, and a combination procedure in 21 knees. Knees were graded as 2, 3, or 4, depending on the depth and severity of the lesion. The best results were in Grades 2 and 3 disease treated by trephine and drilling or facetectomy. Six patients required further patellar surgery during the follow-up period. The purpose of surgical treatment of the patellar articular surface is to relieve pain and preserve the mechanical advantage of the patella for normal knee function.

Adolescent↗
PubMed1980

Corneal curvature changes associated with penetrating keratoplasty: a mathematical model.

A mathematical derivation of the effect of penetrating keratoplasty on corneal curvature was used to examine many variables in corneal surgery. The amount of wound disparity taken up by the recipient cornea was found to be the major factor in determining the amount of astigmatism induced by host wound/donor tissue size disparities. The amount of disparity showed as essentially linear relationship with the amount of astigmatism, approximately 0.4 diopters for each 0.1 mm of wound disparity for each 10% of the amount of the distortion taken up by the cornea (7.5 mm trephine). The smaller the trephine, the more distortion could be expected for each increment of wound disparity. Variations in the corneal curvature of the donor cornea had a minimal effect on the amount of keratoplasty-induced astigmatism.

Astigmatism↗
PubMed1995

[Percutaneous vertebral biopsy. Assessment of results].

The results were reviewed of 81 percutaneous trephine biopsies performed under fluoroscopic or CT guidance from January, 1989, to August, 1994, in 78 patients with thoracic or lumbar vertebral lesions. All the patients presented abnormal findings at conventional radiography and questionable CT or MR findings. A fine-needle sample was obtained as a complementary tool in 9 patients and material for microbiologic culture in 5 patients. Clinical and pathologic findings were correlated for each patient. Biopsy always permitted to obtain sufficient material for the histologic examination; its overall accuracy was 91%. The technique exhibited the highest diagnostic sensitivity in vertebral tumors (100%) and the lowest sensitivity in vertebral infections (69%). Complementary fine-needle sampling was useful especially in small osteolytic lesions, while the microbiologic examination was often negative. There was only one pneumothorax due to the maneuver. To conclude, percutaneous trephine biopsy of thoracic and lumbar spine lesions is a valuable tool for tumor diagnosis which usually spares the patients open surgery.

Adolescent↗
PubMedDate not supplied

A simple punching device for use in penetrating keratoplasty.

A method of supporting donor cornea for trephination is described. On a base of heated and then cooled paraffin, a series of small indentations are made with a sterile acrylic ball, 15 mm in diameter, about one third of its volume deep. The donor cornea is then placed in one of the indentations for trephination.

Cornea↗
PubMed1995

Penetrating keratoplasty with vitreoretinal surgery using the Eckardt temporary keratoprosthesis: modified technique allowing use of larger corneal grafts.

UNLABELLED: We report our experience with the Eckardt temporary keratoprosthesis including a technique modification allowing use of larger corneal grafts. We combined penetrating keratoplasty with vitreoretinal surgery using the Eckardt keratoprosthesis in 24 eyes of 24 patients in two patient groups: trauma (n = 11) and nontrauma (n = 13). Our technique modification involved centering a larger partial trephination for the donor cornea around the smaller trephination used for the keratoprosthesis. After the keratoprosthesis was removed, we excised host cornea graft. With the exception of visual acuity (VA), the outcomes were similar for both trauma and nontrauma groups, and combined results were as follows. Corneal grafts remained clear in 71% of patients at a mean follow-up period of 16 +/- 3 (SE) months. For the trauma and nontrauma groups, VA improved in 82 and 23%, and decreased in 18% and 38.5%, respectively. Postoperative loss of VA was due primarily to retinal scarring (47%) and phthisis bulbi (37%). Only one case of graft rejection occurred. Postoperatively, the larger corneal grafts (8.0 and 8.5 mm) were less steep, and residual astigmatism was more easily managed than with the "recommended" (7.2 mm) size. CONCLUSIONS: Larger corneal grafts allow less astigmatism and a more normal corneal curvature. Theoretical advantages also include faster rehabilitation of vision, better predictability for intraocular lens implant power calculations, and transplantation of more endothelial cells. The Eckardt will continue to be a useful tool and our technique modification allowing use of larger corneal grafts should enhance its utility.

Adult↗
PubMed1994

A comparison of the effects of automated percutaneous diskectomy and conventional diskectomy on intradiscal pressure, disk geometry, and stiffness.

Diskectomy, chemonucleolysis, percutaneous diskectomy, and laser ablation are used to treat patients with sciatica. The effects of percutaneous diskectomy on the intradiscal pressure of the human disk are not known. Our aims were to determine (a) whether removal of nucleus through automated percutaneous diskectomy significantly reduces intradiscal pressure without altering the disk geometry and stiffness, and if so, how much nucleus removal is required to achieve these goals; and (b) whether the effects of conventional diskectomy on these same parameters are equivalent to removal of nucleus through automated percutaneous diskectomy. Cyclic compressive loads of 20-900 N were applied to lumbar disks. Conventional diskectomy or automated percutaneous diskectomy (performed for 40 min with biomechanical measurements made four times at 10-min intervals) was then performed under zero load and the specimens retested under the same cyclic compressive loading. There were significant (p < 0.01) decreases in intradiscal pressure (by 7% under 900 N) after 10 min of automated percutaneous lumbar diskectomy. There were no further significant decreases in pressure during the next 30 min of percutaneous diskectomy. There were also significant decreases in pressure due to a puncture hole made with the Nucleotome trephine alone, without removal of disk material, and there was no difference in pressure after trephining alone and after percutaneous diskectomy. Decreases in disk height were significant, ranging from 5% at 10 min to 7% at 40 min of treatment. There were equivalent decreases in intradiscal pressure and disk height due to removal of similar amounts of nucleus during conventional diskectomy and during 40 min of percutaneous diskectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1996

Radial distribution of tocopherols in rhesus monkey retina and retinal pigment epithelium-choroid.

PURPOSE: To map vitamin E as a function of distance from the foveal center in the primate retina and retinal pigment epithelium (RPE)-choroid. METHODS: Eyecups from rhesus monkeys were dissected with circular trephines so that the innermost disc, centered on the fovea, was in the center of a series of concentric rings. Two different types of dissection were performed. For one type, the authors used circular trephines with diameters of 1, 4, 8, and 10 mm (1,4-D), whereas for the other type the diameters were 2, 5, 8, and sometimes 10 mm (2,5-D). When possible, the neural retina was separated from the RPE-choroid. Tissues were analyzed for vitamin E, retinyl palmitate, and protein. RESULTS: Surface area, volume, and protein were used as indexes of the amount of tissue analyzed. Distributions of vitamin E in neural retina were dependent on the tissue metric used and type of dissection performed. However, regardless of the tissue metric used, the central 1-mm disc of the 1,4-D was, on average, higher in vitamin E content than was the central 2-mm disc of the 2,5-D. This was particularly true when volume was the tissue metric. From the average values of vitamin E in a series of concentric discs, a composite plot of the vitamin E concentration in the neural retina was generated that took into consideration both types of dissection. That plot displayed a local maximum in the fovea and then precipitously declined to a minimum in the region between 0.5 and 1.0 mm eccentricity (near the foveal crest); at greater eccentricities, the vitamin E concentration rose to a value similar to that in the fovea, i.e., the composite plot indicated that vitamin E has a V-shaped distribution in the central neural retina. Vitamin E distribution in the RPE-choroid, with surface area as the tissue metric, also was measured. For this tissue, the foveal region displayed a local maximum. CONCLUSIONS: By combining the results of two different types of dissection, the authors found that in the neural retina, vitamin E displayed a minimum near the foveal crest. This minimum correlated anatomically with the site at which areolar (geographic) atrophy frequently occurs in retinal pigment epithelial cells in the human disease, age-related macular degeneration.

Animals↗
PubMed1996

Hinge keratoplasty.

A simple trephination technique is described that allows the surgeon to be prepared to handle an expulsive hemorrhage before it occurs. After trephination is performed, the host button is excised except for a 1 clock hour width of tissue. This hinge allows the attached button to fold over the corneal rim away from the surgical field. There is no interference with subsequent intraocular procedures. Should expulsive hemorrhage develop, the attached button can be immediately flipped into place and the wound quickly sewn closed.

Eye Hemorrhage↗
PubMed1996

Small B cell NHL and their leukemic counterpart: differences in subtyping and assessment of leukemic spread.

Three subtypes of small lymphocytic lymphoma were studied, namely B cell chronic lymphocytic leukemia (B-CLL), mantle cell lymphoma (MCL) and follicle center lymphoma (FCL). Agreement between tissue diagnosis, based on the proposal for a revised European-American classification of lymphoid neoplasms from the International Lymphoma Study Group, and the cytomorphological diagnosis on peripheral blood and/or bone marrow smears, using the proposals for the classification of chronic (mature) B and T lymphoid leukemias of the French-American-British Cooperative Group, was studied. Full agreement was found in 90% of the CLL and 82% of the FCL cases. In MCL cases, agreement was 65% including all cases classified as intermediate/mantle zone lymphoma according to FAB criteria. The incidence of bone marrow involvement detection in trephines compared to smears was equal in CLL (both 100%) and slightly higher in MCL (56 vs 48.5%); in FCL, however, trephine biopsies provided more reliable material (71 vs 35%).

Biopsy↗
PubMed1995

A survey of corneal graft practice in the United Kingdom.

A questionnaire designed to survey current corneal graft practice was sent to 498 consultant ophthalmologists in the United Kingdom. Three hundred and twenty-nine completed questionnaires (66%) were returned. Seventy per cent of these were from consultants who perform corneal grafts, of whom 36% had a specialist interest in corneal surgery. The survey found that most consultants preferred to perform corneal grafts on an inpatient basis with the patient under general anaesthesia. Agreement (> 80%) was also found in the following areas: use of a hand-held trephine, concurrent cataract surgery (if indicated), post-operative immunosuppression, and refraction to assess post-operative astigmatism. There was less agreement on the choice of donor material, use of tissue matching, donor-trephine size disparity, suture technique, relative timing of trabeculectomy surgery (if required), the management of intraocular lenses during surgery for pseudophakic bullous keratopathy, timing of discharge after surgery, use of prophylactic acyclovir, management of astigmatism, routine removal of all corneal sutures, and discharge of uncomplicated cases from routine follow-up.

Anesthesia, General↗
PubMedDate not supplied

[Inhibition of angiogenesis in the cornea with amiloride].

INTRODUCTION: For its transparency, avascularity and possibility of measurement of the new vessels ingrowth, cornea is a frequent model for angiogenesis research. New vessels are made in several phases: after the action of the stimulus, there is a localised fragmentation of the basal membrane and the extracellular matrix around the involved capillary. Then, endothelial cells migrate through the openings in the capillary wall and the lysis of the extracellular matrix continues as a new vessel is being formed. Enzymes, plasminogen-activators, convert plasminogen from the blood and tissues to plasmin which starts proteolytic cascade of the lysis of the extracellular matrix. Amilorid, previously known as a diuretic, is found to be a competitive inhibitor of plasminogen activator-urokinase (u-PA). Its effect was shown in the prostaglandin-induced model of corneal vascularization [6]. PURPOSE: The purpose of this work is to show that amilorid acts as an angiostatic in the traumatic model of corneal vascularization. MATERIALS AND METHODS: There were two groups of experimental animals (rabbits, weight 1.5-3 kg). Deepitelisation and trephination were performed on all corneas (traumatic model of vascularisation). The first group of animals (17 eyes) was given 15 mg of amilorid (Sigma) intraperitoneally for five days, while the control group consisted of 7 eyes. Neovascularization was measured after 5 and 15 days. Animals were sacrificed on day 15. Three eyes from each group were tested for corneal wound tensile strength. RESULTS: In the experimental group there was a 0.5 mm ingrowth of the new vessels after the first five days and no further ingrowth till the end of the experiment. In the control group there was a 2 mm ingrowth after five days, and a further 1 mm after the next ten days. No statistical difference was found with regard to tensile strengths of the corneal wounds between the two groups. DISCUSSION: Although the traumatic model is closer to the clinical situation than the prostaglandin-induced vascularization model, more potential angiogenic factors are involved. Trephination damages basal membrane which may liberate angiogenic substances (heparan-sulphate, for example) [9]. Products of damaged cells attract leucocytes by haemotaxis. Also, hyopxia in the depth of the wound may be the site of macrophage induced angiogenesis [10]. It is difficult to say at which point amilorid acts but, considering the new vessel ingrowth for only 0.5 mm, it might be at the beginning of the process (lysis of extracellular matrix). CONCLUSION: Amilorid acts as angiogenesis inhibitor in the traumatic corneal vascularization model without changing the tensile strength of the wound.

Amiloride↗
PubMed1977

[Biopsy in rectal cancer recurrences].

The design of a modified needle for trephine biopsy in rectal cancer recurrence in the perineal region is described. The needle design is simple and can be readily manufactured in a mechanic shop. The biopsy material obtained is large enough to type the tumor histologically. The technic of biopsy is not complicated and requires no special skill. Trephine-biopsy for rectal cancer recurrences may substitute completely knife biopsy, being a safe maneuvre in the complex diagnosis of rectal cancer recurrence.

Biopsy, Needle↗