ABSTRACT.Purpose: To look at the epithelial nature of Salzmann nodular degeneration (SND) and its possible relation with the aetiology of the subepithelial collagen deposition.Methods: Histological slides of 28 patients with SND were analysed for limbal and central corneal epithelial markers. Expression pattern of these markers in the basal layer of the epithelium was analysed and compared to the expression pattern in central corneal and limbal epithelium. Statistical analysis was performed by means of analysis of variance. Results: Expression of the epithelial stem cell marker ABCG2 and p63 was low in SND. Expression of CK12, a marker for terminally differentiated epithelium, was low, as well. But, CK19 and Enolase-alpha expressions were significantly increased and resembled the expression pattern of transient amplifying cells (TAC) of the limbus. Conclusion: The epithelium in SND shows similar characteristics as TAC of the limbus and seems to be metabolically more active than the differentiated central corneal epithelium. This could be related to the deposition of subepithelial collagen fibrils seen in SND and points out a possible involvement of the corneal epithelium in the aetiology of Salzmann nodular degeneration.

Neurothrombectomy with TPV is feasible, effective, and safe. The recanalization rate compares favorably with reported data in the literature. Improved structural radiopacity may facilitate neurothrombectomy or influence the course of action during retrieval.

Interventional Radiology 906Chang DH et al. Ergebnisse: Es gab keine signifikanten Unterschiede bezüglich der diagnostischen Akzeptanz und der Komplikationsrate in beiden Gruppen. Im Vergleich zu SDCT erreichte LDCT eine Dosisreduktion im Median um 68,6 %. Die Implementation der iterativen Rekonstruktion war bezüglich der Rauschunterdrückung und der subjektiven Bildqualität der FBP überlegen. Bezüglich der Aufhärtungsartefakte ergab sich kein Unterschied zwischen beiden Gruppen. Schlussfolgerung: Das LDCT-Protokoll erzielt eine signifikante Reduktion der Strahlenexposition um mehr als 2/3, während die diagnostische Sicherheit und Präzision beibehalten werden. Die iterative Rekonstruktion ist, aus der Analyse der objektiven und subjektiven Auswertung der Bildqualität zu bevorzugen. Kernaussagen:▶ Niedrigdosisprotokolle (LDCT) sind bei CT-gesteuerten Interventionen an der Lunge bezüg-Abstract ! Purpose: To compare the radiation doses and image qualities of computed tomography (CT)-guided interventions using a standard-dose CT (SDCT) protocol with filtered back projection and a lowdose CT (LDCT) protocol with both filtered back projection and iterative reconstruction. Materials and Methods: Image quality and radiation doses (dose-length product and CT dose index) were retrospectively reviewed for 130 patients who underwent CT-guided lung interventions. SDCT at 120 kVp and automatic mA modulation and LDCT at 100 kVp and a fixed exposure were each performed for 65 patients. Image quality was objectively evaluated as the contrast-to-noise ratio and subjectively by two radiologists for noise impression, sharpness, artifacts and diagnostic acceptability on a four-point scale.Results: The groups did not significantly differ in terms of diagnostic acceptability and complication rate. LDCT yielded a median 68.6 % reduction in the radiation dose relative to SDCT. In the LDCT group, iterative reconstruction was superior to filtered back projection in terms of noise reduction and subjective image quality. The groups did not differ in terms of beam hardening artifacts. Conclusion: LDCT was feasible for all procedures and yielded a more than two-thirds reduction in radiation exposure while maintaining overall diagnostic acceptability, safety and precision. The iterative reconstruction algorithm is preferable according to the objective and subjective image quality analyses.

ObjectiveThe aim of the study reported here was to evaluate patients’ satisfaction with implantation of venous access devices under local anesthesia (LA) with and without additional oral sedation.Materials and methodsA total of 77 patients were enrolled in the prospective descriptive study over a period of 6 months. Subcutaneous implantable venous access devices through the subclavian vein were routinely implanted under LA. Patients were offered an additional oral sedative (lorazepam) before each procedure. The level of anxiety/tension, the intensity of pain, and patients’ satisfaction were evaluated before and immediately after the procedure using a visual analog scale (ranging from 0 to 10) with a standardized questionnaire.ResultsPatients’ satisfaction with the procedure was high (mean: 1.3±2.0) with no significant difference between the group with premedication and the group with LA alone (P=0.54). However, seven out of 30 patients (23.3%) in the group that received premedication would not undergo the same procedure without general anesthesia. There was no significant influence of lorazepam on the intensity of pain (P=0.88). In 12 out of 30 patients (40%) in the premedication group, the level of tension was higher than 5 on the visual analog scale during the procedure. In 21 out of 77 patients (27.3%), the estimate of the level of tension differed between the interventionist and the patient by 3 or more points in 21 out of 77 patients (27.3%).ConclusionOverall patient satisfaction is high for implantation of venous access devices under LA. A combination of LA with lorazepam administered orally might not be adequate for patients with a high level of anxiety and tension. The level of tension is often underestimated by the interventionist. Pre-procedural standardized questionnaires could be used to identify patients for whom a gradual approach of individualized sedation may be more effective.

Objectives: To investigate the effects of low- and high-frequency deep brain stimulation (DBS) on the nucleus accumbens (ACC) and the adjacent internal capsule in 3 patients with obsessive-compulsive disorder (OCD) using blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) under intraoperative conditions. Methods: After placement of the electrode in the right ACC, the patients underwent an MR scan inside the operating room. BOLD imaging was performed and interpreted using a boxcar paradigm with alternating high-frequency stimulation of the ACC and the internal capsule versus rest. Correlation maps were calculated employing SPM99. Results: During high-frequency stimulation of the right ACC, focal activation could be found in the right striatum, the right frontal lobe and the right hippocampus, whereas low-frequency stimulation was correlated to right insular activation. Interpretation: Intraoperative BOLD-fMRI is feasible during DBS surgery of OCD patients. Our results support the existence of an ipsilateral hemispheric circuit involving the frontal lobe, anterior cingulate, parahippocampal gyrus and striatum. Intraoperative fMRI may be used to acquire additional information regarding the pathophysiology of OCD that can be used to improve the results of DBS in OCD.