Recognizing cisplatin as a potential radiation recall trigger: case report and focused systematic review.

We present a case of mild radiation recall dermatitis triggered by cisplatin chemotherapy given simultaneously to re-irradiation. The dermatitis area correlated to skin exposure of the previous radiation therapy, characterizing the reaction clearly as a recall. Cisplatin has not yet been recognized as a potential trigger for recall reactions. Although it was part of several reported multidrug trigger combinations, all review works referred to cisplatin as not suspicious, suggesting the combination partner as the effector. We performed a focused systematic literature review aiming to re-evaluate the real role of cisplatin as a (co-)triggering factor. In total, 30 reported cases were found, 90% triggered by multidrug combinations. The latter tended to cause more severe symptoms. Besides findings supporting the 20 Gy-threshold theory, no correlation between radiation dose and severity or prevalence was found. Recognition of cisplatin as a trigger of the recall phenomenon and its supportive management may prevent unnecessary cessation of systemic chemotherapy. Systematic reporting of recall events as a secondary endpoint of prospective clinical trials applying radiation therapy could support understanding the recall phenomenon.

New strategies for high precision surgery of the temporal bone using a robotic approach for cochlear implantation.

The aim of the study was to demonstrate a collision-free trajectory of an instrument through the facial recess to the site of planned cochleostomy guided by a surgery robot. The indication for cochlear implantation is still expanding toward more substantial residual hearing. A cochleostomy as atraumatic as possible will influence the preservation of inner ear function. The employment of a highly precise instrument guidance using a robot could represent a feasible solution for a constant reproducible surgical procedure. Screw markers for a point-based registration were fixed on a human temporal bone specimen prepared with a mastoidectomy and posterior tympanotomy. A DICOM dataset has been generated thereof in a 64-multislice computer tomography (CT). A virtual trajectory in a 3D model has been planned representing the path of instrumentation toward the desired spot of cochleostomy. A 1.9-mm endoscope has been mounted onto the robot system RobaCKa (Staeubli RX90CR) to visualize this trajectory. The target registration error added up to 0.25 mm, which met the desirable tolerance of <0.5 mm. A collision-free propagation of the endoscope into the tympanic cavity via the facial recess has been performed by the robot and the spot of cochleostomy could be visualized through the endoscope. Using a DICOM dataset of a high-resolution CT and a robot as a positioning platform for surgical instruments could be a feasible approach to perform a highly precise and constant reproducible cochleostomy. Furthermore, it could be a crucial step to preserve substantial residual hearing in terms of expanding the indications for cochlear implantation.

High precision cochleostomy by use of a pulsed CO2 laser - an experimental approach.

A precise cochleostomy is a crucial step in cochlear implantation, particularly if residual hearing is to be preserved. A contactless ablation of the promontory bone by a pulsed CO(2) laser system seems to be a promising approach. The bone is removed by a scan head controlled laser beam in sequential scan cycles with a pulse rate of 50-100 mus. Digital picture analysis and pattern detection are used to identify the membranous lining of the cochlea. We achieved a bone ablation in a micrometer range per scan cycle with the laser. A perforation of the promontory bone could be detected by automatic pattern detection. The enhancement of automatic pattern detection can lead to a minimally invasive, function-preserving laser cochleostomy.

Pneumocele as a rare differential diagnosis in trigeminal irritation.

A case of a pneumocele concerning the maxillary sinus causing trigeminal irritation is presented. Pneumoceles are rare conditions of an abnormal dilatation of a paranasal sinus containing only air, lined by unremarkable mucosa, and associated with a bony defect. Symptoms, diagnostic findings, therapy, possible causes, and pathogenesis are discussed.