[Incidence of Revision Operations due to Retinal (Re-)Detachment Following Removal of the Silicone Oil Tamponade with Special Emphasis on the Time Course]. / Häufigkeit der Revisionsoperationen aufgrund einer (Re-)Ablatio retinae nach operativer Entfernung der Silikonölendotamponade: Untersuchung des zeitlichen Verlaufes.

In a retrospective analysis of the clinical data, the frequency and timing of revision surgery due to retinal (re-)detachment was studied in patients undergoing complete silicone oil removal surgery for the first time, in 2005, 2010 and 2015. Overall, the clinical data from 512 patients (1.7 : 1 - men : women) were evaluated over a follow-up period of 1 year to 11 years. The gender ratio was 15.4 : 14.4% - men : women; there were no clear gender differences in the incidence of retinal (re-)detachments. A total of 77/512 patients (15%) were reviewed for retinal detachment after complete silicone oil removal. During the first 90 postoperative days, this affected 58 (75%) of the 77 patients, and during the first postoperative year, 69 (89%) of the 77 patients. The Kaplan-Meier-analysis for 2010 confirmed that 75% of the revision surgeries were performed in the first 90 days after silicone oil removal. Patients prior to scheduled silicone oil tamponade should be advised on the shift in the risk profile for retinal (re-)detachment during the period after silicone oil removal and on necessary narrow control intervals within the first 90 days of silicone oil removal.

[The Influence of the Type of Anaesthesia on the Frequency of Postoperative Haemorrhage Requiring Revision After Removal of the Silicone Oil Tamponade]. / Der Einfluss der Narkoseart auf die Häufigkeit revisionsbedürftiger postoperativer Nachblutungen nach Entfernung der Silikonölendotamponade.

In this retrospective data analysis, it was examined whether the mode of anesthesia influenced postoperative haemorrhage in patients with first time complete silicone oil removal in 2002, 2005, 2010, 2014 - 2016 in our clinic and if there was a change in frequency over time. Haemorrhage was defined as a postoperative haemorrhage within 2 weeks after the operation and which led to revision vitrectomy. In all, there were 939 operations and 9 cases of postoperative surgery requiring revision in the analysed years. Even though the number of patients with intubation anesthesia (355) was smaller than the number with local anesthesia (584), the majority of patients with postoperative haemorrhage had been given intubation anesthesia (6). This difference corresponds to a trend (p = 0.089) towards a lower rate of postoperative haemorrhage with local anesthesia, which could encourage the surgeon to perform silicone oil removal under local anaesthesia. Over the course of time, there was a decline in postoperative haemorrhage. In 2002, 2005 and 2010 there were 7 cases of postoperative haemorrhage, but only 2 in the years 2014 - 2016. Aside from the higher proportion of operations under local anaesthesia, the decline in the frequency of postoperative haemorrhage may be attributed to "smoother extubation", the emergence of trocar-guided surgical procedure and the use of anti-VEGF therapy - all leading to a change in the spectrum of illnesses treated by silicone oil instillation.

A swarm of slippery micropropellers penetrates the vitreous body of the eye.

The intravitreal delivery of therapeutic agents promises major benefits in the field of ocular medicine. Traditional delivery methods rely on the random, passive diffusion of molecules, which do not allow for the rapid delivery of a concentrated cargo to a defined region at the posterior pole of the eye. The use of particles promises targeted delivery but faces the challenge that most tissues including the vitreous have a tight macromolecular matrix that acts as a barrier and prevents its penetration. Here, we demonstrate novel intravitreal delivery microvehicles-slippery micropropellers-that can be actively propelled through the vitreous humor to reach the retina. The propulsion is achieved by helical magnetic micropropellers that have a liquid layer coating to minimize adhesion to the surrounding biopolymeric network. The submicrometer diameter of the propellers enables the penetration of the biopolymeric network and the propulsion through the porcine vitreous body of the eye over centimeter distances. Clinical optical coherence tomography is used to monitor the movement of the propellers and confirm their arrival on the retina near the optic disc. Overcoming the adhesion forces and actively navigating a swarm of micropropellers in the dense vitreous humor promise practical applications in ophthalmology.