Quantification of corneal transparency in post-mortem human corneas using laser scatter image analysis.

BACKGROUND: The cornea is a highly transparent structure covering the anterior one-fifth of the eyeball. The suitability of post-mortem donor corneas for keratoplasty is currently qualitatively assessed. This makes inferences prone to bias and subjective variability. This study aimed to develop a simple, feasible and cost-effective method to quantify corneal transparency. METHODS: An artificial anterior chamber was modified to provide a central transparent passage and a standardised pressure segment. All corneas graded 'fair' were included in this study. The corneoscleral buttons were mounted on the modified artificial anterior chamber. The mounted chamber was held in a horizontal position at a fixed distance from a white projection screen. The laser source was placed in alignment with an artificial anterior chamber so that it passed through the centre of the cornea. A camera mounted on a tripod stand was placed at a prefixed distance. An image of the scattered laser spot that formed after the laser passed through the mounted cornea on the screen was captured with a single digital camera and standardised settings. Image analysis was performed using ImageJ, an open platform for scientific image analysis. The average red pixel intensity, max intensity, and full-width half max were calculated. RESULTS: The average red intensity was 132.45 ± 6.65 SD. The mean for max intensity was 51.1 ± 3.78 SD and the full-width half max 787.7 ± 84.7 SD. CONCLUSION: Laser quantification is a simple and cost-effective method of quantifying corneal transparency. The study lends proof to the principle involved.

Creación, funcionamiento y control de bancos de córneas y esclerótica: acuerdo gubernativo No. 440-2013 / Creation, operation and control of corneal and scleral banks: government agreement No. 440-2013

El documento tiene algunos problemas de nitidez, que dificultan un tanto su lectura, pero solo al inicio. Las afecciones de córnea, son una de las 5 enfermedades que causan ceguera y que son prevenibles. Describe las normas y requisitos para su autorización y funcionamiento. Incluye varias definiciones de conceptos inherentes al tema del acuerdo. Además de describir la organización y estructura de los bancos de córneas, propone la conformación de un comité de trasplantes, describiendo los profesionales que deben conformarlo y sus específicas funciones. Describe también las funciones de los técnicos de cada establecimiento, público y/o privado. Enumera y describe las características físicas (infraestructura), así como el equipamiento y detalles complementarios que deberán ser cumplidas por cada establecimiento solicitante. Otro tanto hace con los detalles, tanto de donadores como de receptores.

Blood vessels recovered with organs and intended for use in organ transplantation. Final rule.

The Food and Drug Administration (FDA) and the Health Resources and Services Administration (HRSA) are amending their regulations to include as part of an organ those blood vessels recovered with the organ that are intended for use in organ transplantation (HRSA regulation); and to exclude such blood vessels from the definition of human cells, tissues, or cellular or tissue-based products (HCT/Ps) (FDA regulation). The purpose of this final rule is to amend the regulations so that blood vessels recovered with organs and intended for use in organ transplantation, and labeled as such, are governed by the regulations pertaining to organs. The regulation of other recovered blood vessels remains unchanged. We (HRSA and FDA) believe that this change will eliminate the burden resulting from an organ procurement organization's efforts to comply with both FDA and HRSA rules with respect to blood vessels (FDA jurisdiction) and organs (HRSA jurisdiction).

[Quality of kidney procurement in Germany. Ten years experience and 486 renal allografts in a single centre]. / Qualität der Leichennierenentnahme in Deutschland. 10-Jahres-Erfahrungen mit 486 transplantierten Leichennieren an einem Zentrum.

BACKGROUND: Organ damage during organ procurement is believed to be an increasing problem among transplant centres. However, only very few published data are available. The purpose of our study was to examine the quality of kidney procurement in Germany. METHODS: We retrospectively analyzed all allograft renal transplants performed at our centre from 1996 to 2005. All kidneys were retrieved in Germany and allocated by Eurotransplant. RESULTS: From a total of 486 cadaveric kidneys, 103 (21.2%) were not correctly retrieved. Nevertheless, none of the organs had to be rejected. In 18 (3.7%), a technically insufficient organ retrieval was associated with a considerable extension of the surgical procedure or complications. CONCLUSIONS: Technically insufficient kidney procurement rarely results in clinical consequences. However, surgeons performing organ retrieval should be better trained. Whether adequate technical proficiency is achieved with ten supervised cases, as requested by the German Medical Association, remains to be determined. In our opinion, a further interdisciplinary course that trains surgeons in more refined techniques of organ procurement is desirable.

The zygomatic bone as a potential donor site for alveolar reconstruction--a quantitative anatomic cadaver study.

The aim of this cadaver study was to evaluate the possibility of using the zygomatic bone as an intraoral bone harvesting donor site and to determine the safety of this harvesting procedure. In addition, the volume of bone material harvested from the zygomatic bone was measured. Twenty fixed adult cadavers were used to yield a total of 40 zygomatic bone harvest sites, from which bone was collected. The volume of bone obtained from the zygomatic harvests was measured with a water displacement method and by compressing the graft into a syringe. The safety of the technique was evaluated by assessing possible encroachment upon the neighbouring structures. After bone harvesting, the zygomatic sites were exposed and evaluated for visible perforations or fractures. Possible damage to the neighbouring tissues was also examined with computed tomography scans at 18 sites in nine cadavers. The average bone graft volume obtained from the zygomatic bone was measured to be 0.53 ml (SD 0.25) with water displacement and 0.59 ml (SD 0.26) with the syringe. The complications in the zygoma included 15 small perforations into the maxillary sinus and 7 perforations into the infratemporal fossa. CT scans showed that bone could be harvested safely without encroaching upon the orbital floor or the surrounding nerves and vessels in the zygoma. The zygomatic bone is a safe intraoral donor site for the reconstruction of small- to medium-sized alveolar defects.

Retrieving organs from non-heart-beating organ donors: a review of medical and ethical issues.

PURPOSE: The increasing gap between numbers of individuals awaiting organ replacement surgery and the supply of organs available for transplant underpins attempts to increase the number of organs available. One practice, used in other countries, is the recovery of organs from non-heart-beating organ donors (NHBD). The purpose of this review is to discuss ethical issues surrounding the use of organs from these donors. SOURCE: Narrative review from selected Medline references, and other published reports. PRINCIPAL FINDINGS: NHBD protocols have been established in many countries including the United States. Despite numerous publications, and extensive debate in the literature, significant ethical issues remain unresolved in the retrieval of organs from donors that have died from cessation of cardiac activity. The ethical concerns primarily arise in the determination of death, the tension between the time constraints on recovering organs viable for transplantation, and procedures to enhance organ viability. Despite a concerted effort in the United States, less than half of the organ procurement organizations have NHBD protocols. CONCLUSION: Canadian centres can learn from the difficulties encountered in other centres that have developed NHBD protocols. A moratorium on Canadian NHBD protocols should be considered until a National consensus reflecting Canadian values has been undertaken.