Endoscopic resection of an intraventricular cavernoma: a case report.

Cerebral cavernous malformations occur in 0.5% of the population. They consist of thin-walled vessels and can be found as congenital or sporadic lesions. Most of them are asymptomatic, however, due to their anatomical features blood leakage into the surrounding tissue can cause severe neurological symptoms. Although risk of bleeding is low, symptomatic lesions should be treated, with microsurgical resection being the therapy of choice for surgically accessible cavernomas. Intraventricular cavernous malformations are a rare subtype, and due to their anatomical localization, they are eligible for endoscopic surgery. However, there are only a few reports on endoscopic resection of intraventricular cavernomas to be found in the literature. We report the case of a 48-year-old woman who suffers from multiple cerebral cavernous malformations. Since the first diagnosis, several of these cavernomas had been removed in open microsurgical interventions. Most recently, a new lesion arose intraventricularly, adjacent to the ependymal wall of the right lateral ventricle. In follow-up, cranial MR imaging microbleeding and an increasing size were detected. Eventually, the lesion was endoscopically removed. Presurgery the patient suffered from right-sided sensibility loss and gait disturbances as a consequence of prior surgeries. Postsurgery, no new neurological symptoms could be found. We here present MR images and intraoperative pictures as well as a short video of the resection itself. In our opinion, endoscopic resection of intraventricular cavernomas should be considered in selected cases.

Late-onset hydrocephalus in a child with Joubert syndrome: a case report.

INTRODUCTION: The ciliopathy "Joubert syndrome" was first described in 1969 by Dr. Marie Joubert and most subtypes follow an autosomal recessive inheritance. The complex disorder shows typical clinical features, such as hyperventilation, abnormal eye movements, and retardation. A pathognomonic midbrain-hindbrain malformation, the molar tooth sign, can be found on magnetic resonance imaging of the brainstem. There are a little more than 200 reports of Joubert syndrome in the literature. CASE PRESENTATION: We report a case of a 9-year-old boy who developed a progressive hydrocephalus starting from the age of 4. He underwent VP shunt placement at 8 years, which relieved hydrocephalus-related clinical symptoms and put development of the macrocephalus to a halt. CONCLUSION: Neonatal hydrocephalus due to the altered anatomy of the posterior fossa has been reported earlier, but to our knowledge, this is the first case of a delayed onset of hydrocephalus in a patient with Joubert syndrome.

Dynamic infrared thermography (DIRT) for assessment of skin blood perfusion in cranioplasty: a proof of concept for qualitative comparison with the standard indocyanine green video angiography (ICGA).

PURPOSE: Complications in wound healing after neurosurgical operations occur often due to scarred dehiscence with skin blood perfusion disturbance. The standard imaging method for intraoperative skin perfusion assessment is the invasive indocyanine green video angiography (ICGA). The noninvasive dynamic infrared thermography (DIRT) is a promising alternative modality that was evaluated by comparison with ICGA. METHODS: The study was carried out in two parts: (1) investigation of technical conditions for intraoperative use of DIRT for its comparison with ICGA, and (2) visual and quantitative comparison of both modalities in a proof of concept on nine patients. Time-temperature curves in DIRT and time-intensity curves in ICGA for defined regions of interest were analyzed. New perfusion parameters were defined in DIRT and compared with the usual perfusion parameters in ICGA. RESULTS: The visual observation of the image data in DIRT and ICGA showed that operation material, anatomical structures and skin perfusion are represented similarly in both modalities. Although the analysis of the curves and perfusion parameter values showed differences between patients, no complications were observed clinically. These differences were represented in DIRT and ICGA equivalently. CONCLUSIONS: DIRT has shown a great potential for intraoperative use, with several advantages over ICGA. The technique is passive, contactless and noninvasive. The practicability of the intraoperative recording of the same operation field section with ICGA and DIRT has been demonstrated. The promising results of this proof of concept provide a basis for a trial with a larger number of patients.

Quality of life in patients with unilateral vestibular schwannoma on wait and see - strategy.

OBJECTIVE: A 'wait and see' strategy is an option when managing patients with small vestibular schwannomas (VS). A risk of growth and worsening of hearing may influence a patient's daily quality of life (QOL). Therefore, the present study focused on QOL parameters in patients who are on a 'wait and see' strategy following magnetic resonance imaging (MRI)-based diagnosis of small unilateral VS. PATIENTS AND METHODS: Sixty-five patients (mean age 64.4 years; male:female, 32:33) who suffered from a small unilateral VS (9.34 mm, range 1.5-23 mm) between 2013 and 2016 were included in a prospective single center study. During follow-up, in addition to clinical and neurological examinations and MRI imaging, all patients answered the Short Form 36 questionnaire once to characterize QOL. Additionally, the severity of tinnitus was determined by the Mini-TQ-12 from Hiller and Goebel. RESULTS: It was found during follow-up that there was no lowering of QOL in patients with small VS who were on 'wait and see' strategy compared with Germany's general population and no tumor growth was detected in 53 patients (81.5%). Patients with a tumor diameter larger than 10 mm did not suffer from stronger tinnitus, vertigo or unsteadiness than the group with an average tumor size, which is smaller than 10 mm. Sixty-two patients (95.4%) showed ipsilateral hearing loss and three of these reported deafness (4.6%). Severe vertigo or tinnitus is connected with lower levels of mental component scale and physical component scale. These findings reduced the QOL (p = 0.05). CONCLUSION: In our series, QOL is not influenced in patients with unilateral untreated small VS in comparison to Germany's general population. This is helpful information when advising patients during follow-up and finding out the optimal timing of individual treatment.

Factors associated with non-participation and dropout among cancer patients in a cluster-randomised controlled trial.

We investigated the impact of demographic and disease related factors on non-participation and dropout in a cluster-randomised behavioural trial in cancer patients with measurements taken between hospitalisation and 6 months thereafter. The percentages of non-participation and dropout were documented at each time point. Factors considered to be potentially related with non-participation and dropout were as follows: age, sex, marital status, education, income, employment status, tumour site and stage of disease. Of 1,338 eligible patients, 24% declined participation at baseline. Non-participation was higher in older patients (Odds Ratio [OR] 2.1, CI: 0.6-0.9) and those with advanced disease (OR 2.0, CI: 0.1-1.3). Dropout by 6 months was 25%. Dropout was more frequent with increased age (OR 2.8, CI: 0.8-1.2), advanced disease (OR 3.0, CI: 1.0-1.2), being married (OR 2.4, CI 0.7-1.1) and less frequent with university education (OR 0.4, CI -1.3 to -0.8) and middle income (OR 0.4, CI -0.9 to -0.7). When planning clinical trials, it is important to be aware of patient groups at high risk of non-participation or dropout, for example older patients or those with advanced disease. Trial designs should consider their special needs to increase their rate of participation.

Adult long-term outcome of patients after congenital hydrocephalus shunt therapy.

INTRODUCTION: Even though shunt surgery has been an established and widely accepted treatment for congenital hydrocephalus for five decades, long-term follow-up and functional outcome data is rare. PATIENTS AND METHODS: Sixty-nine patients were examined after congenital hydrocephalus had been treated between 1971 and 1987 at the Department of Pediatric Surgery (University of Leipzig) within the first 12 months of life. Median age of patients was 32 years (range 25-42 years). Patients agreed to undergo a contemporary hydrocephalus assessment. RESULTS: Seven patients (10.1%) became shunt-independent before adulthood. By the age of 20, 82% of the patients had needed at least one shunt revision, 100% by the age of 30. 21.7% of the primary valves (Spitz-Holter) remained intact without revision until today up to 35 years (mean functional intactness 23 years). Shunt infections occurred in 4.3% of primary implantations. 48% of the patients had a good functional outcome (mRS = 0-1). 40.9% of the patients attended regular school. In summary, 75% patients work on a daily basis. 44.6% live an independent life, 35.4% rely on parental supervision, and 20% depend on professional care institutions. CONCLUSION: Compared to the pre-shunt era, surgery within the first year of life is advantageous regarding visual function, educational progress, and social results. The outcome achieved throughout childhood remains stable during adult life as long as catastrophic events of shunt malfunction can be prevented. Epilepsy, motor deficits, acute shunt dysfunction, and problems of social integration as well as aging parental caregivers seem to be prominent factors of morbidity in adulthood.

[Deep brain stimulation using simultaneous stereotactic electrode placement: an alternative to conventional functional stereotaxy?]. / Tiefe Hirnstimulation mittels simultaner stereotaktischer Elektrodenplatzierung : Eine Alternative zur konventionellen funktionellen Stereotaxie?

BACKGROUND: Deep brain stimulation (DBS) has become a reliable method in the treatment of movement disorders, e.g. idiopathic Parkinson's disease (IPD) and is technically based on stereotaxy. The Starfix® platform is a new type of stereotactic frame that allows an individualized and patient-optimized therapeutic regimen in IPD. OBJECTIVES: The aim of this study was to retrospectively compare the outcomes of IPD patients who underwent surgery with the use of conventional stereotactic frames (31 patients) to those who underwent implantation of DBS with the use of Starfix® frames (29 patients). MATERIAL AND METHODS: Surgery time, the unified Parkinson's disease rating scale III (UPDRS/III) score, L-dopa and L-dopa equivalent doses (LED) were compared prior to surgery as well as 4 weeks, 12 weeks, 6 months and 1 year postoperatively. RESULTS: The IPD-related symptoms improved significantly in both groups with respect to the UPDRS III score (conventional 69.6% vs. 72.4% Starfix®). After surgery significant reductions of L-dopa and LED were seen in both groups. Inherent advantages of the Starfix® platform included simultaneous positioning of the stimulating electrodes and a significant reduction in surgical time. CONCLUSION: In summary, both stereotactic procedures are reliable and safe procedures for the placement of stimulating electrodes as well as the stimulation effect achieved. The logistical uncoupling of presurgical planning from surgical therapy emphasizes the benefits of the individualized stereotactic procedure.

Stent graft visualization and planning tool for endovascular surgery using finite element analysis.

PURPOSE: A new approach to optimize stent graft selection for endovascular aortic repair is the use of finite element analysis. Once the finite element model is created and solved, a software module is needed to view the simulation results in the clinical work environment. A new tool for interpretation of simulation results, named Medical Postprocessor, that enables comparison of different stent graft configurations and products was designed, implemented and tested. METHODS: Aortic endovascular stent graft ring forces and sealing states in the vessel landing zone of three different configurations were provided in a surgical planning software using the Medical Imaging Interaction Tool Kit (MITK) software system. For data interpretation, software modules for 2D and 3D presentations were implemented. Ten surgeons evaluated the software features of the Medical Postprocessor. These surgeons performed usability tests and answered questionnaires based on their experience with the system. RESULTS: The Medical Postprocessor visualization system enabled vascular surgeons to determine the configuration with the highest overall fixation force in 16+/-6 s, best proximal sealing in 56+/-24s and highest proximal fixation force in 38+/- s. The majority considered the multiformat data provided helpful and found the Medical Postprocessor to be an efficient decision support system for stent graft selection. The evaluation of the user interface results in an ISONORM-conform user interface (113.5 points). CONCLUSION: The Medical Postprocessor visualization software tool for analyzing stent graft properties was evaluated by vascular surgeons. The results show that the software can assist the interpretation of simulation results to optimize stent graft configuration and sizing.

Impact of navigated-control assistance on performance, workload and situation awareness of experienced surgeons performing a simulated mastoidectomy.

BACKGROUND: Navigated control (NC) is an advanced image-guided navigation system that provides an additional control function to enhance patient safety. It automatically stops the surgical instrument if it comes close to critical anatomical structures that need to be protected during surgery. The purpose of this study was to explore the human performance consequences of computer-based navigated control assistance. METHODS: Seven experienced surgeons conducted a simulated mastoidectomy manually and with support of the NC system. The impact on surgical performance, workload and situation awareness was analysed. RESULTS: NC support led to a better quality of surgical outcome and a lower level of physiological effort during surgery. Cost effects were reflected in reduced time efficiency and an increased subjectively experienced workload. CONCLUSION: The results demonstrate the potential of NC support in terms of lower workload and enhanced patient safety. Cost effects might be reduced by remodelling the control function.

The use of 5-aminolevulinic acid fluorescence guidance in resection of pediatric brain tumors.

INTRODUCTION: Whereas in the adult population 5-Aminolevulinic acid (5-ALA) fluorescence guidance has been widely accepted for improving the extent of tumor resection, the application in children remains an off-label use. Even though most pediatric study protocols require a complete resection for improving outcome parameters, only few pediatric patients have been operated with fluorescence guidance, and it remains questionable, whether and which pediatric tumors show useful fluorescence. We present casuistic reports of application of 5-ALA in children collected from three different neurosurgical departments. PATIENTS AND METHODS: In children with suspected malignant intracerebral tumor or recurrence, individual informed consent was obtained in each case from the parents. 5-ALA was administered according to the adult protocol, with 20 mg/kg, 2 h before induction of anesthesia. We retrospectively analyzed 18 patients (13 male, 5 female; age 3-18 years), using the intraoperative neurosurgical protocol, the postoperative MRI results, and the follow-up clinical examinations. RESULTS: The use of 5-ALA fluorescence guidance proved to be safe in our group of pediatric patients. Fluorescence guidance was most useful for recurrent glioblastoma resection. Medulloblastoma tissue displayed fluorescence only inconsistently, and most pilocytic astrocytoma remained without staining. Ganglioglioma showed partial staining in the central tumor areas, without allowing the use for circumferent resection. CONCLUSION: The off-label use of 5-ALA fluorescence guidance in pediatric patients appears to be most useful in recurrent high-grade gliomas. Fluorescence accumulation in other pediatric brain tumor entities is not predictable and should be evaluated in future clinical studies before being integrated into the current treatment protocols.

Acute two-compartment low pressure hydrocephalus--a case report.

A case of an 8-year-old-boy with shunt-dependent occlusive hydrocephalus after resection of a cerebellar medulloblastoma is presented, who experienced repeated episodes of severe neurologic deterioration with signs and symptoms of raised intracranial pressure after spinal tapping. However, intracranial pressure was recorded within low ranges, only up to the opening pressure of the implanted adjustable shunt valve. Multiple shunt revisions were performed, until the condition was recognized as acute normal pressure hydrocephalus. Either enforced recumbency and downadjustment of the valve system to 0 cm H(2)O alone or external ventricular drainage seems to be successful to resolve the critical condition, depending on severity of the symptoms. The case illustrates that acute pathologic enlargement of the ventricular system is not always associated with increased intracranial pressure, even when typical signs and symptoms are present. The very rare entity of acute normal pressure hydrocephalus by two separated compartments is postulated based on the pulsatile vector force theory of brain water circulation.

[The 'Surgical Deck': a new generation of integrated operational rooms for ENT]. / Das "Surgical Deck": Eine neue OP-Generation für die HNO-Chirurgie.

BACKGROUND: Existing operating room concepts do not meet modern technological opportunities anymore. The "Surgical Deck" is supposed to represent a prototype for a new operating room generation. The objective of the project is to achieve a better integration of functions and to develop an innovative concept for a highly developed surgical workstation. MATERIAL AND METHODS: 3 working areas are defined: Surgical, Airway and Technical Cockpit. The evaluation was conducted on 284 surgeries carried out from 01.08. 2011 to 31.01. 2012. The evaluation team consisted of 6 surgeons, 3 surgery nurses, 3 anesthesiologists and 4 anesthesia nurses. Within a detailed analysis, the data of 50 FESS surgeries were compared to those of a control group. RESULTS: Within the FESS group, the average slot time was reduced by 13%. 88.2% of those questioned assessed ergonomics as being better than in the conventional OR. 71.5% stated that the Surgical Deck provided an added value with regard to the surgical procedure. 91.3% confirmed that the system control required additional training. 79.3% described the cost-benefit-ratio as appropriate. For 96% of the surgeries, respondents said that they were feeling adequately supported by the technology. CONCLUSION: The results show a clear advantage of the system architecture. The Surgical Deck may present a solid foundation with regard to the transfer of the system into the clinical practice. This is relevant for new assistance functions such as process control software or navigation-based collision warning systems. It is to be expected that the project will significantly contribute to further develop the future surgical workstation and its standardization.

Effectiveness of bevacizumab for radiation-induced cerebral necrosis in children.

INTRODUCTION: Bevacizumab has been reported to effectively reduce cerebral edema caused by radiation therapy. However, only limited data with a short follow-up in tumor patients are available so far. PATIENTS AND METHODS: Two children suffering from hemorrhage from arteriovenous malformation (AVM) have been treated with stereotactic radiotherapy and developed radiation-induced cerebral edema with deteriorating neurological status despite maximized steroid therapy. Bevacizumab administration at 5 mg/kg body weight was initiated every 2 weeks. RESULTS: Bevacizumab treatment rapidly ameliorated the neurological deficits, malignant edema and prevented catastrophic complications. Corticoid therapy could be reduced and discontinued. However, after 18 months, both patients showed identical or worse neurological status than before bevacizumab therapy. AVM radiation therapy had been successful to completely obliterate AVMs. DISCUSSION: In our limited experience, bevacizumab may be an effective and safe option for rescue therapy for malignant cerebral edema on the basis of radiation-induced necrosis especially in patients who experience rapid deterioration despite corticoid therapy and/or intolerable steroid side effects. Despite the fact that functional improvement could not be achieved in long-term outcome patients significantly stabilized and improved during periods of acute deterioration. In order to determine the long-term effectiveness of bevacizumab further investigation in placebo-controlled studies with a higher number of patients are required.

[Clinical experience with navigation functions for temporal bone surgery : interim result after 40 patients]. / Klinischer Einsatz von Navigationsfunktionen in der Felsenbeinchirurgie : Zwischenbilanz nach 40 Patienten.

PROBLEM: Although robust algorithms for registration and segmentation are available, the majority of surgical approaches to the temporal bone are nowadays made without navigation assistance. Beside instrument navigation (IN), functions such as distance control (DC) and navigated control (NC) can be used. This study analyzes the application of these navigation functionalities in lateral skull base and middle ear surgery. PATIENTS AND METHODS: A total of 41 patients with an indication of temporal bone approaches were included. The navigation was realized with an optoelectric navigation system with both non-invasive and invasive markers. Parameters such as surgical time, Level of Quality (LoQ) index, and Change of Surgical Strategy (COS) index were evaluated. RESULTS: In 14.6% of patients, the conventional mode of IN was used. In 70.7% of cases, the function DC was also used. In another 14.6% of cases, the function NC was used to control the speed of the drill. The facial nerve was the dominant segmented risk structure for active navigation. The time for setup was on average 7.78 min. The LoQ index score was on average 66 points. In 17% of the patients, surgeons evaluated the assistance mode as "necessary for the surgery". No technical-related complications were recorded. CONCLUSION: This study proves the usability of navigation technology for temporal bone surgery in clinical routine. DC and NC are two additional features for higher acceptance of navigation in microscopic surgery.

Surgical workflow management schemata for cataract procedures. process model-based design and validation of workflow schemata.

OBJECTIVE: Workflow guidance of surgical activities is a challenging task. Because of variations in patient properties and applied surgical techniques, surgical processes have a high variability. The objective of this study was the design and implementation of a surgical workflow management system (SWFMS) that can provide a robust guidance for surgical activities. We investigated how many surgical process models are needed to develop a SWFMS that can guide cataract surgeries robustly. METHODS: We used 100 cases of cataract surgeries and acquired patient-individual surgical process models (iSPMs) from them. Of these, randomized subsets iSPMs were selected as learning sets to create a generic surgical process model (gSPM). These gSPMs were mapped onto workflow nets as workflow schemata to define the behavior of the SWFMS. Finally, 10 iSPMs from the disjoint set were simulated to validate the workflow schema for the surgical processes. The measurement was the successful guidance of an iSPM. RESULTS: We demonstrated that a SWFMS with a workflow schema that was generated from a subset of 10 iSPMs is sufficient to guide approximately 65% of all surgical processes in the total set, and that a subset of 50 iSPMs is sufficient to guide approx. 80% of all processes. CONCLUSION: We designed a SWFMS that is able to guide surgical activities on a detailed level. The study demonstrated that the high inter-patient variability of surgical processes can be considered by our approach.

[The first clinical use of an Dynamic Registration Tool for Navigation in FESS]. / Der erste klinische Einsatz einer dynamischen (Nach-) Registrierung für die Navigation in der FESS.

BACKGROUND: The effective register accuracy in an situs issues a challenge to the employment of instrument navigation in the ENT Surgery. The idea of the initially determined process Dynamic Registration Supply (DRS) is to improve the register accuracy by the automatic, and interoperability of the register. MATERIALS AND METHODS: The aim was to determine clinical use of DRS. Opto-electrical system Navigation Panel Unit, vs. 4.0.0 with the functionality DRS was used. Experiments were carried out on 95 patients who had so called FESS. The data of a control group were available to researchers. The measuring log includes among other things following parameters: retooling time, cutting-suture time, frequency of use of the navigated pointer, frequency of additional registration. RESULTS: At least once during the procedure DRS has been activated in 85 of 95 interventions (89.5). The time required increased by 15% accumulated 189 s per intervention. The most frequently used additional registration was in the region of sphenoid sinus. The surgeons underlined that out of 95 surveys in 75 cases the DRS rendered the instrument navigation more precise, while 1% of 93 cases considered this function as unwanted. CONCLUSION: The first clinical study for use of an automatic algorithm for recognition and reduction of faulty registration of a CT, navigation was successful. The findings suggest that by using automatic intraoperative registration DRS consisting inaccuracy can be reduced. In practice this means an efficient quality improvement of the Navigation.

The impact of psychiatric comorbidity on quality of life in patients undergoing herniated disc surgery.

BACKGROUND: Recent studies examined the role of psychiatric comorbidity in the process of rehabilitation in patients undergoing herniated disc surgery. These patients suffer from physical and psychosocial complaints or symptoms, which impact their everyday life negatively and the success of rehabilitation potentially. The objectives of this study are (1) to examine the quality of life (QoL) in disc surgery patients and to compare the findings with reference data from the general German population, and (2) to investigate the impact of psychiatric comorbidity on QoL of patients undergoing herniated disc surgery. METHODS: This study consists of 305 patients aged between 18 and 55 years who took part in face-to-face interviews during their hospital stay. Psychiatric comorbidity was assessed with the Composite International Diagnostic Interview (CIDI-DIA-X). By means of the 36-Item Short-Form Health Survey (SF-36), QoL was assessed in patients undergoing herniated disc surgery with and without psychiatric comorbidity. These findings were compared with the QoL of a representative sample of the general German population. RESULTS: Compared with the general population, QoL in patients with herniated disc surgery was lower in all domains of the SF-36. Psychiatric comorbidity impacts the QoL in patients with herniated disc surgery in all SF-36 domains except "physical function". The patients with psychiatric comorbidity showed significantly lower levels of QoL in the domains "bodily pain", "vitality", "social function", "role emotional", and "mental health". CONCLUSIONS: Psychiatric comorbidity has a substantial adverse effect on QoL in patients undergoing disc surgery. Therefore, it will be necessary to diagnose psychiatric comorbidities at an early stage and to include psychosocial interventions in the treatment of herniated disc patients aimed at improving deficits in psychosocial functioning and QoL.

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. Progression was defined as an increase of ⩾2 mm in the largest diameter in the magnetic resonance imaging. Preoperative tumor size, facial nerve function estimated using the House-Brackmann score (HBS), time to progression, and recurrence rate were analysed and related to the extent of resection. RESULTS: In 28 cases (group I), a capsular remnant was left. In 22 cases (group II), tumor removal was complete. In group I, nine patients (32·1%) showed progression. In group II, two patients (9·1%) developed a recurrent tumor, no significance (P = 0·085). In groups I and II, 53·6 and 59·6% had a good function of the facial nerve (HBS I+II), 28·6% in group I and 13·5% in group II had a moderate disturbance (HBS III+IV), and 17·9% in group I and 27·7% in group II had a poor function (HBS V+VI). There was no significant difference between median preoperative tumor size and facial nerve function within patients with HBS III and IV. CONCLUSION: Complete tumor removal may be associated with a risk of functional loss, whereas near total tumor removal may be associated with a higher risk of progression.