Recording of surgical processes: a study comparing senior and junior neurosurgeons during lumbar disc herniation surgery.

Background: Evaluating surgical practice in the operating room is difficult, and its assessment is largely subjective.

Objective: Recording of standardized spine surgery processes was conducted to ascertain whether any significant differences in surgical practice could be observed between senior and junior neurosurgeons.

Methods: Twenty-four procedures of lumbar discectomies were consecutively recorded by a senior neurosurgeon.

Systematic user-based assessment of "Navigated Control Spine" / Systematische, nutzerzentrierte Evaluation von "Navigated Control Spine".

The aim of this study was the systematic preclinical assessment of a new mill for spinal surgery. This mill automatically switches off at predefined workspace margins. The system is called the "Navigated Control Spine".

Assessment of technical needs for surgical equipment by surgical process models.

The presented approach introduces a method for estimating the potential benefit of a surgical assist system prior to its actual development or clinical use. The central research question is: What minimal requirements must a future system meet so that its use would be more advantageous than a conventional or already existent method or system, and how can these requirements be obtained from routine clinical data? Forty-three cases of lumbar discectomies were analyzed with regard to activities related to bone ablation in order to predict the temporal requirements for an alternative strategy of using a surgical assist system for bone ablation. The study recorded and analyzed surgical process models (SPM), which are progression models with detailed and exact-to-the-second representations of surgical work steps, as a sensible means for the detailed quantification of the temporal needs of the system.

Spheno-orbital meningiomas: outcome after microsurgical treatment: a clinical review of 30 cases.

Objective: Spheno-orbital meningiomas represent a delicate subtype of intracranial meningiomas involving the sphenoid wing, orbit and important neurovascular structures such as cavernous sinus, carotid artery or optic nerve. Insidious and aggressive dural, bone and orbital involvement contains several defiances to adequate resection, which provides high rates of recurrence.

Methods: This retrospective case analysis consisted of 30 patients, who were surgically treated for spheno-orbital meningiomas performing a fronto-pterional approach by or under the supervision of the senior author (J.

Reconstructive and ophthalmologic outcomes following resection of spheno-orbital meningiomas.

Purpose: To assess long-term stability and aesthetic and functional outcomes of orbital reconstruction after resection of spheno-orbital meningiomas using calvarial bone grafts.

Methods: A series of 21 patients were retrospectively examined after an average follow-up period of 65.6 months with regard to their personal satisfaction and also proptosis, ocular function, and reconstructive outcome.

First clinical application of a navigation-controlled shaver in paranasal sinus surgery.

Conventional, pointer-based navigated Functional Endoscopic Sinus Surgery (FESS) has been shown to have certain limitations: necessity of instrument change for navigation, changes in the surgeon's line-of-sight axis, and limited length of use of the navigation information. These limitations result in negative consequences regarding the surgeon's attentiveness in any given situation, as well as in his cognitive work-load. The principle of Navigated Control offers advantages concerning these problems and limitations of the conventionally navigated FESS.

Requirement specification for surgical simulation systems with surgical workflows.

Surgical simulations are normally developed in a cycle of continuous refinement. This leads to high costs in simulator design and as a result to a very limited number of simulators which are used in clinical training scenarios. We propose using Surgical Workflow Analysis for a goal-oriented specification of surgical simulators.

The navigation-controlled drill in temporal bone surgery: a feasibility study.

Background: This study examines the feasibility of a navigation-controlled (NC) drill for surgery on the petrosal bone in an experimental environment. According to the principle of NC, the drill is to be switched off automatically once the borders of the workspace are exceeded during a mastoidectomy.

Materials And Methods: The registration is based on an optical navigation system with navigation software (MiMed).

Advanced approach for intraoperative MRI guidance and potential benefit for neurosurgical applications.

Purpose: To present an advanced approach for intraoperative image guidance in an open 0.5 T MRI and to evaluate its effectiveness for neurosurgical interventions by comparison with a dynamic scan-guided localization technique.

Materials And Methods: The built-in scan guidance mode relied on successive interactive MRI scans.

Evaluation of a navigation system for ENT with surgical efficiency criteria.

The aim of this study is the evaluation of a navigation system (NaviBase) for ENT surgery. For this purpose, a new methodology for the evaluation of surgical and ergonomic system properties has been developed. The practicability of the evaluation instruments will be examined using the example of the overall assessment of the system in comparison with the current surgical standard and with other systems using clinical efficiency criteria.

Surgical PACS for the digital operating room. Systems engineering and specification of user requirements.

For better integration of surgical assist systems into the operating room, a common communication and processing plattform that is based on the users needs is needed. The development of such a system, a Surgical Picture Aquisition and Communication System (S-PACS), according the systems engineering cycle is oulined in this paper. The first two steps (concept and specification) for the engineering of the S-PACS are discussed.

Intraoperative MRI to guide the resection of primary supratentorial glioblastoma multiforme--a quantitative radiological analysis.

Patients with supratentorial high-grade glioma underwent surgery within a vertically open 0.5-T magnetic resonance (MR) system to evaluate the efficacy of intraoperative MR guidance in achieving gross-total resection. For 31 patients, preoperative clinical data and MR findings were consistent with the putative diagnosis of a high-grade glioma, in 23 cases in eloquent regions.

[Structure of an interdisciplinary pituitary outpatient care unit at the University Hospital of Leipzig and results for treatment of prolactin and growth hormone secreting pituitary tumors].

Background: Treatment of patients with pituitary adenomas is complex and involves several medical specialties. At the Medical Center of the University of Leipzig, Germany, an interdisciplinary pituitary outpatient care unit has been established for 6 years.

Methods: The interdisciplinary collaboration and the outcome of patients with growth hormone-(GH-) and prolactin-secreting pituitary adenomas are described.

Fundamentals of force feedback and application to a surgery simulator.

Force feedback increases the effectiveness of virtual-reality surgery training systems. An overview of the fundamentals of applying force feedback is presented. An impedance control technique and data processing methods for stability preservation are illustrated.

Quantitative assessment of parenchymal and ventricular readjustment to intracranial pressure relief.

A 26-year-old patient underwent endoscopic third ventriculostomy for the treatment of obstructive hydrocephalus. 3D volume data sets were obtained at 3 T before surgery and three times after surgery. Off-line analysis of individual imaging data (initial linear registration, intensity adjustment, and final nonlinear registration of pre- to postoperative MR images) yielded 3D displacement fields representing the postoperative structural brain change.

[Intraoperative use of an open mid-field MR scanner in the surgical treatment of cerebral gliomas].

The aim of the present study was to evaluate the effectiveness of intraoperative MRI guidance in achieving more gross-total resection in case of primary brain tumors. We studied 12 patients with low-grade glioma and 19 patients with high-grade glioma who underwent surgery within a vertically open 0.5 T MR system.

Investigation of time-dependency of intracranial brain shift and its relation to the extent of tumor removal using intra-operative MRI.

The object of the paper is to investigate intra-operative brainshift and its relation to the extent of tumor removal. Repeated T1w 3D datasets were acquired at different time points intra-operatively (T0; T1; T2..

Iterative neuronavigation using 3D ultrasound. A feasibility study.

Intra-operative ultrasound (iUS) can generate 2D images in real-time as well as near real-time 3D datasets of the current situation during an intervention. Tracked ultrasound can locate the images in 3D space and relate them to patient, devices, andpre-operative planning data. Therefore, tracked US is an efficient means for controlling the validity of pre-operative planning, recognition of changes (brain shift) during the intervention, replanning of the operational path due to situational changes (iterative navigation), and finally, controlling the results (residual tumor).