ARTIS Pheno®: a potential tool for cochlear implant surgery.

PURPOSE: Cochlear implantation is a standard approach to hearing rehabilitation and encompasses three main stages: appropriate patient selection, a challenging surgical procedure, which should be as atraumatic as possible and preserve cochlear structures, and lifelong postoperative follow-up. Computed tomography (CT) is performed to assess postoperative implant position. The Siemens Advanced Radar Target Identification System (ARTIS) Pheno provides fluoroscopic imaging during surgery and has so far been mainly used by cardiologists, neurosurgeons and trauma surgeons. METHODS: Six patients with difficult anatomy or a challenging medical history were selected for a surgical procedure, during which we planned to use the ARTIS Pheno to accurately position and assess implant position under fluoroscopy during and immediately after surgery. In all six cases, the ARTIS Pheno was used directly in the surgical setting. The procedures were performed in cooperation with the neuroradiology department in an interdisciplinary manner. RESULTS: In all six patients, fluoroscopy was used to visualise the procedure at different stages of surgery. In five patients, the procedure was successfully completed. This approach allowed us to finally assess implant position and confirm the correct and complete insertion of the electrode while the patient was still under anaesthesia. CONCLUSION: These cases showed positive surgical outcomes. Although the procedure is more complex than a standard approach, patients can be managed in a safe, effective and appropriate manner. The assessment of implant position in real time during surgery leads to greater patient and surgeon satisfaction. The approach presented here ensures a high quality of cochlear implant surgery even in difficult surgical situations and meets the requirements of modern surgery.

[Morphological and functional diagnostics of coronary artery disease by computed tomography]. / Morphologische und funktionelle Diagnostik der koronaren Herzkrankheit mittels Computertomographie.

Computed tomography coronary angiography (cCTA) is a safe option for the noninvasive exclusion of significant coronary stenoses in patients with a low or moderate pretest probability for coronary artery disease (CAD). Furthermore, it also allows functional and morphological assessment of coronary stenoses. The European Society of Cardiology (ESC) guidelines on the diagnosis and management of chronic coronary syndrome published in 2019 have strengthened the importance of cCTA in this context and for this reason it has experienced a considerable upgrade. The determination of the Agatston score is a clinically established method for quantifying coronary calcification and influences the initiation of drug treatment. With technologies, such as the introduction of electrocardiography (ECG)-controlled dose modulation and iterative image reconstruction, cCTA can be performed with high image quality and low radiation exposure. Anatomic imaging of coronary stenoses alone is currently being augmented by innovative techniques, such as myocardial CT perfusion imaging or CT-fractional flow reserve (FFR) but the clinical value of these methods merits further investigation. The cCTA could therefore develop into a gatekeeper with respect to the indications for invasive coronary diagnostics and interventions.

[SMAR3T©-a new time-saving diagnostic emergency room management algorithm]. / SMAR3T© ­ ein neuer zeitsparender diagnostischer Schockraumalgorithmus.

BACKGROUND: Primary computed tomography (CT) plays an increasingly important role in diagnosing life-threatening conditions in polytrauma patients; however, it is associated with two major problems: suboptimal interobserver reliability with unstructured reports especially when the reporting is undertaken by physicians in training during working hours and a delay in beginning urgent surgical interventions, which is mainly due to the time taken until the CT report is available and less to the technical time necessary for the CT. This is why the clinical benefits of a primary CT scan in hemodynamically unstable patients after polytrauma is currently under interdisciplinary discussion. OBJECTIVE: The present study focused on the development and evaluation of a standardized imaging and reporting protocol for initial CT diagnostics of injuries that need immediate treatment after polytrauma. METHODS: In this study 30 patients after polytrauma were subjected to a novel imaging and reporting protocol, SMAR3T, consisting of an imaging protocol with decreased thin-slice axial scan sequences and a standardized structured reporting protocol. These were compared to conventional emergency room CT protocol with respect to time efficiency and quality of the results. RESULTS: The application of the SMAR3T algorithm significantly reduced the time from scan to reporting from an average of 59.6 ± 4.2 min to an average of 8.5 ± 0.6 min (p < 10-23). With the conventional reporting protocol as well as the novel SMAR3T reporting protocol, all life-threatening conditions and injuries requiring immediate treatment were detected. CONCLUSION: Based on the results of 30 CT scans in polytraumatized patients, the SMAR3T algorithm significantly reduced the time to surgical intervention without compromising diagnostic accuracy with respect to life-threatening conditions. Additionally, the reduction in imaging data volume could facilitate telemedical transmission of data to superordinate centers.

Validating Baboon Ex Vivo and In Vivo Radiation-Related Gene Expression with Corresponding Human Data.

The research for high-throughput diagnostic tests for victims of radio/nuclear incidents remains ongoing. In this context, we have previously identified candidate genes that predict risk of late-occurring hematologic acute radiation syndrome (HARS) in a baboon model. The goal of the current study was to validate these genes after radiation exposure in humans. We also examined ex vivo relative to in vivo measurements in both species and describe dose-response relationships. Eighteen baboons were irradiated in vivo to simulate different patterns of partial- or total-body irradiation (TBI), corresponding to an equivalent dose of 2.5 or 5 Sv. Human in vivo blood samples were obtained from patients exposed to different dose ranges: diagnostic computerized tomography (CT; 0.004-0.018 Sv); radiotherapy for prostate cancer (0.25-0.3 Sv); and TBI of leukemia patients (2 × 1.5 or 2 × 2 Sv, five patients each). Peripheral whole blood of another five baboons and human samples from five healthy donors were cultivated ex vivo and irradiated with 0-4 Sv. RNA was isolated pairwise before and 24 h after irradiation and converted into cDNA. Gene expression of six promising candidate genes found previously by us in a baboon model ( WNT3, POU2AF1, CCR7, ARG2, CD177, WLS), as well as three genes commonly used in ex vivo whole blood experiments ( FDXR, PCNA, DDB2) was measured using qRT-PCR. We confirmed the six baboon candidate genes in leukemia patients. However, expression for the candidate gene FDXR showed an inverse relationship, as it was downregulated in baboons and upregulated in human samples. Comparisons among the in vivo and ex vivo experiments revealed the same pattern in both species and indicated peripheral blood cells to represent the radiation-responsive targets causing WNT3 and POU2AF1 gene expression changes. CCR7, ARG2, CD177 and WLS appeared to be altered due to radiation-responsive targets other than the whole blood cells. Linear dose-response relationships of FDXR, WNT3 and POU2AF1 using human ex vivo samples corresponded with human in vivo samples, suggesting that ex vivo models for in vivo dose estimates can be used over a wide dose range (0.001-5 Sv for POU2AF1). In summary, we validated six baboon candidate genes in humans, but the FDXR measurements underscored the importance of independent assessments even when candidates from animal models have striking gene sequence homology to humans. Since whole blood cells represented the same radiation-responsive targets for FDXR, WNT3 and POU2AF1 gene expression changes, ex vivo cell culture models can be utilized for in vivo dose estimates over a dose range covering up to 3.5 log scales. These findings might be a step forward in the development of a gene expression-based high-throughput diagnostic test for populations involved in large-scale radio/nuclear incidents.

[Abdominal actinomycosis: a rare differential diagnosis to colon carcinoma and Morbus Crohn]. / Abdominelle Aktinomykose: Eine seltene Differenzialdiagnose zu Kolonkarzinom und Morbus Crohn.

Abdominal actinomycosis is a rare, chronic and slowly progressive granulomatous disease. The clinical presentation of abdominal actinomycosis shows a great variability and it often mimics other intraabdominal pathologies like chronic inflammatory bowel diseases or malignancies. A correct diagnosis can rarely be established before radical surgery especially in patients with advanced tumors and an acute clinical presentation. Actinomyces are considered to be residential saprophytes in the gastroinstetinal tract and require a mucosal lesion to cause an opportunistic infection. Microbiological culture is the gold standard for diagnosis, despite high false-negative rates in daily routine testing. Therefore, actinomycosis is diagnosed more often histopathologically by detection of sulfur granules in the surgical specimen. The postoperative treatment of choice is intravenous followed by oral penicillin over a few weeks due to good response and low resistance rates. There are no evidence based recommendations concerning the duration of antibiotic treatment, but a treatment of at least 4 weeks depending on the clinical course is advisable to achieve permanent recovery. The following case report deals with a severe clinical course of an abdominal actinomycosis. The 49-year-old female patient had to be operated as an emergency under suspicion of an advanced colonic carcinoma with bowel obstruction. She needed an elaborate operative and postoperative therapy.

[Primary amelanotic meningeal melanomatosis]. / Primäre amelanotische meningeale Melanomatose.

Primary melanocytic lesions of the central nervous system are rare. The spread of melanoma cells primarily into the meningeal layers is referred to as meningeal melanomatosis. A few case reports about either intracranial or intraspinal primary meningeal melanoma were published in the past. The amelanotic variation of primary melanoma in the central nervous system is a very rare event and so far no cases of primary amelanotic meningeal melanomatosis have been described in the current literature. We present a case with combined multiple intracranial and intraspinal primary malignant amelanotic melanomas.

[Percutaneous CT-guided destruction versus microsurgical resection of lumbar juxtafacet cysts]. / Perkutane CT-gesteuerte Destruktion vs. mikrochirurgische Resektion lumbaler Juxtafacettzysten.

BACKGROUND: Microsurgical resection is the standard treatment of lumbar juxtafacet cysts. Percutaneous computed tomography (CT) guided destruction of the cyst could be an alternative modality for inoperable patients. Comparative prospective studies for both treatment strategies do not exist. MATERIALS AND METHODS: This study involved a non-randomized, prospective trial on 45 patients suffering from sciatica or claudication caused by lumbar juxtafacet cysts. Of the patients 25 were operated on microsurgically and 20 patients were primarily treated using percutaneous CT-guided cyst destruction. RESULTS: The treatment in both groups was performed without complications in all patients. All patients treated microsurgically were pain-free (mean postoperative interval 27 months) but only 8 out of 20 patients treated percutaneously recovered completely (mean post-treatment interval 24 months). The remaining 12 out of 20 patients showed no relevant improvement and were operated on microsurgically. CONCLUSION: Minimally invasive cyst destruction is not a viable alternative to microsurgical resection considering the long-term outcome, neither in this study nor in the reviewed literature.

[Verification of malleus head fixation : computed tomography as diagnosis standard]. / Verifikation der Hammerkopffixation : Computertomographie als Diagnosestandard.

Malleus head fixation and otosclerosis causing conductive hearing loss are often difficult to differentiate by clinical features. Up to now exploratory anterior tympanotomy was necessary to distinguish these pathologies. The case of a 22-year-old male suffering from conductive hearing loss of the right ear is presented. Otosclerosis was suspected and high-resolution CT scanning of the petrous bone was performed. The diagnosis was confirmed radiologically by the detection of an isolated malleus head fixation. Instead of explorative anterior tympanotomy, radiological and audiological controls were combined for the follow-up.