[Hirsutism and multinodular goiter in a 40-year-old female watchmaker].

This article presents the case of a female patient with acromegaly caused by ectopic production of growth hormone-releasing hormone (GHRH) secretion. In the presence of typical clinical features of acromegaly but a lack of evidence for a pituitary adenoma the results of somatostatin receptor scintigraphy were indicative of a typical carcinoid of the lungs as the cause of the ectopic secretion of GHRH and the stimulation of pituitary gland growth hormone secretion resulting in acromegaly. Finally, the patient underwent curative surgical treatment.

Recurrence rate, time to progression and facial nerve function in microsurgery of vestibular schwannoma.

Objective: Recurrence rate, time to progression, and facial nerve function were analysed by comparing patients with complete and near total tumor removal after suboccipital craniotomy for vestibular schwannoma surgery.

Methods: From 1996 to 2004, 118 patients with vestibular schwannoma were operated with an interdisciplinary approach. Fifty patients fulfilled the inclusion criteria and were included in the study.

Cerebrospinal fluid leak after microsurgical surgery in vestibular schwannomas via retrosigmoidal craniotomy.

Objective: Cerebrospinal fluid (CSF) leak is still a common complication in surgery of vestibular schwannoma, increasing morbidity and prolonging hospital stay. Our single center study was performed to determine the incidences of CSF leaks after microsurgical removal of vestibular schwannoma via a retrosigmoidal approach with two different surgical closure techniques.

Methods: Between January 2003 and December 2009 in 81 patients, microsurgical tumor resection using a suboccipital, retrosigmoidal approach was performed with an interdisciplinary ENT and neurosurgical management was performed.

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".

Meningiomas involving the sphenoid wing outcome after microsurgical treatment--a clinical review of 73 cases.

Objective: Sphenoid wing meningiomas represent a difficult to access subtype of intracranial meningiomas involving important neurovascular structures such as the optic nerve, cavernous sinus or carotid artery. They cause neurological compromises by direct compression of adjacent cranial nerves. Insidious and aggressive dural, bony, and orbital involvement produces several difficulties for adequate resection leading to higher rates of recurrence.

Evaluation of a navigated and power controlled milling system "navigated control spine" for spinal surgery.

Purpose: The aim of this work was the evaluation of a navigated and power controlled milling system for spine surgery (navigated control spine). The navigation is based on a set of intraoperatively taken fluoroscopic images from different angles. A manually planned workspace limits the power of the mill and assures a higher automatisation degree than any other established navigation system for spine surgery.

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.

[Virtual endoscopy of the nose and paranasal sinuses in real-time. Surgical planning system "Sinus endoscopy" (SPS-SE)].

Problem: The aim of this study was the development and clinical evaluation of a new method for virtual endoscopy of the nose and paranasal sinuses.

Material And Methods: The surgical planning system "sinus endoscopy" (SPS-SE) was completely newly developed. The surfaces of the CT images are represented with direct volume rendering (raycasting) which allows a sufficiently high image repetition frequency with the movement of the virtual endoscopy and material effects for a natural appearance were added.

Automation in surgery: a systematic approach.

This chapter proposes a classification of surgical assistance systems with respect to their type and level of automation. This classification is based on previous work in the field of human factors and takes two aspects into consideration, the type of information-processing function of the surgeon that is supported by the system, as well as the type of function allocation between surgeon and systems. With respect to the former, three basic functions are distinguished, referred to as information acquisition and analysis, decision making and planning, and execution of surgical action.

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.

Navigated control in functional endoscopic sinus surgery.

This study designs and evaluates a mechatronic system to assist ENT surgery, taking as an example a navigation controlled shaver as used in paranasal sinus surgery. The on/off status of the shaver is regulated automatically, depending on the current position of the shaver tip. The working space for the navigation controlled shaver is planned preoperatively as a three-dimensional model and is based on the individual patient's CT data.

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).

Application of intraoperative 3D ultrasound during navigated tumor resection.

Intraoperative 3D ultrasound (3D-iUS) may enhance the quality of neuronavigation by adding information about brain shift and tumor remnants. The aim of our study was to prove the concept of 3D ultrasound on the basis of technical and human effects. A 3D-ultrasound navigation system consisting of a standard personal computer containing a video grabber card in combination with an optical tracking system (NDI Polaris) and a standard ultrasound device (Siemens Omnia) with a 7.

[Manipulator assisted endoscope guidance in functional endoscopic sinus surgery: proof of concept].

Background: Functional endoscopic sinus surgery (FESS) is characterized by single-handed preparation and guidance of the endoscope by the nondominant hand. This results in an additional extension of operation time by up to 15% and ergonomic deficits. The aim of this study is the conception of an automated assistance system for FESS in view of the following questions: (1) Which degree of surgical automation is suitable for FESS? (2) Which design is suitable? (3) What are the properties of the technical system (planning, time, accuracy, precision) of the selected system? (4) Does the system offer potential for a clinical application?

Methods: In all 49 FESS were analyzed for surgical workflows.

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.

[Clinical efficiency and the influence of human factors on ear, nose, and throat navigation systems].

Background: The aim of this study was to evaluate the Navibase navigation system for ear, nose, and throat (ENT) surgery. A new methodology for evaluating surgical and human factors is developed.

Patients And Methods: The evaluation is based on 102 ENT surgical applications, including 89 cases of functional endoscopic sinus surgery (FESS).

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.

Establishing navigated control in head surgery.

Navigated Control (NC) describes an additional control for a tracked power driven instrument within a preoperatively segmented work space. In head surgery the authors first implemented NC in functional endoscopic sinus surgery (FESS). Recently the feasibility of NC for surgery on the petrosal bone is evaluated.

[Workflow analysis to assess the efficiency of intraoperative technology using the example of functional endoscopic sinus surgery].

Evaluation of the efficiency of surgical technology systems has to date been largely subjective. The aim of this study was to develop an ontology for surgical procedures usable workflow structures, and the evaluation of surgical workflow analysis using the example of functional endoscopic sinus surgery (FESS). A total of 38 procedures (20 patients) were included.

Effect of 3T MRI on the function of shunt valves--evaluation of Paedi GAV, Dual Switch and proGAV.

The MR-compatibility of medical implants and devices becomes more and more important with the increasing number of high-field MR-scanners employed. Until the end of 2004, about twenty 3T MR in Germany will be in clinical practice. Patients with hydrocephalus need frequent follow-up MR-examinations to assure correct functioning of a shunt.