Functional implications of short‐term retinal detachment in porcine eyes: study by multifocal electroretinography

Purpose: The aim of the study was to determine the type and magnitude of detectable changes in pig multifocal electroretinography (mfERG) induced by the vitreoretinal surgical procedures necessary to gain access to the subretinal space. Methods: Twenty pigs underwent posterior segment surgery. Six animals had a vitrectomy (V), six had in addition a retinal bleb detachment (V + B); five had in addition a retinal diathermia on the bleb (V + B + D) and three received a retinotomy in the diathermized retinal area (V + B + D + R). mfERG evaluation was performed at baseline and 1 and 6 weeks postoperatively. Selected eyes were enucleated for histological evaluation. Results: The retinal detachments blebs all reattached spontaneously. All four surgical sequences resulted in slight, non‐significant changes in the mfERG peaks. A trend towards an amplitude reduction of the mfERG peaks N1, P1 and N2 were observed within the first postoperative week. After 6 weeks, all amplitudes had normalized. Of the implicit times only that of peak N1 (after retinal diathermia) was prolonged significantly at 1 week (P = 0.037). However, it returned to the preoperative level after 6 weeks. Histologically, the retinal detachment bleb was characterized by transient double layering of the retinal pigment epithelium (RPE) and loss photoreceptor outer segments. Conclusion: Access to the subretinal space in pigs can be gained without permanent detectable changes in the mfERG. A short‐term retinal detachment was found to cause only reversible electrophysiological and histological changes in the outer retina, which suggests that this procedure is tolerated well in the porcine retina. The size of the known destructive lesion (retinotomy) was too small to be detected, given the spatial resolution of the mfERG method applied. In the future, the presented protocol can be used to assess the functional outcome of surgery and transplantation in the subretinal space in pigs.     

Mortality and morbidity of neonates born at <26 weeks of gestation (1998-2003). A population-based study

OBJECTIVE: To describe mortality and morbidity of neonates born at <26 weeks' gestation in a contemporary population-based cohort. METHODS: We analyzed data of neonates born at <26 weeks between 1998 and 2003 in the Federal State of Hesse, Germany. Survival was calculated at 28 days and at discharge from hospital. RESULTS: Out of a total of 800 births, 572 infants were liveborn. Among those admitted for neonatal intensive care, 62.3% survived until day 28. Among the neonates followed until death or discharge, 59.6% were discharged home. Logistic regression analyses showed the following variables to be associated with an increased risk of death: Twins (Odds Ratio (OR) 3.7; 95% Confidence Interval (CI) 1.34-10.26), multiple birth >or=3 (OR 8.14; CI 1.23-53.86), intraventricular hemorrhage (IVH) >or=grade III (OR 4.79; CI 1.89-12.14), clinical risk index for babies score >15 (OR 2.9; CI 1.09-7.76), and a gestational age or=grade III and/or periventricular leukomalacia in 15%, and severe retinopathy of prematurity in 29.8%. CONCLUSIONS: This study provides outcome data derived from a contemporary population-based cohort. Mortality and complication rates remain high.     

Intraoperative radiotherapy of breast cancer

In the systemic therapy of breast cancer, the tumor itself has become the specific target. If possible the surgical excision of breast carcinoma is restricted to the tumor site and aims at an R0 resection of the invasive and preinvasive portions of the carcinoma. Only percutaneous whole-breast radiotherapy irradiates the whole breast. The additional boost irradiation is targeted and significantly improves local control in all age groups. Due to the increased detection of small breast carcinomas in postmenopausal patients by mammographic screening, it is necessary to consider a change of the existing therapeutic practice. Published results of partial irradiation of the breast (intra- as well as postoperatively) show a very high degree of local control with follow-ups of up to 11 years. At present prospective and randomized studies investigate for which patients an intraoperative radiotherapy is sufficient as the sole irradiation method after previous surgery. Intraoperative radiotherapy as a boost preceding percutaneous whole-breast irradiation should already be possible according to a relevant statement of the DEGRO.