Juergen Grauvogel

The impact of tinnitus and vertigo on patient-perceived quality of life after cerebellopontine angle surgery.

BACKGROUNDQuality of life (QOL) has come into focus after treatment for cerebellopontine angle (CPA) lesions. OBJECTIVEThis study compared subjective (tinnitus, vertigo) and objective (hearing loss, facial palsy) results of CPA surgery with patient-perceived impairment of QOL. METHODSA retrospective analysis of a consecutive series of 48 patients operated on for either a vestibular schwannoma or a meningioma in the CPA was performed. Patients subjective impairment of QOL by tinnitus, vertigo, hearing loss, and facial nerve palsy was assessed by a visual analog scale (VAS). Objective facial nerve and hearing function were determined using House-Brackmann and Gardner-Robertson classification systems, respectively. RESULTSThe return rate of questionnaires was 64.4%, with mean follow-up time of 417.2 (± 46.4) days. Mean preoperative tinnitus score was 2.5 (± 0.5) and increased to 4.6 (± 0.7) postoperatively (P < .01). The vertigo score increased from 2.0 (± 0.3) to 5.8 (± 0.6) (P < .001). Pre- and postoperative values for hearing loss were 3.4 (± 0.6) and 5.9 (± 0.7), respectively (P < .01), and for facial nerve palsy 0.7 (± 0.4) compared with 3.1 (± 0.6) postoperatively (P < .01). House-Brackmann grade 1 or 2 was determined in 87.1% of patients before and in 80.6% after surgery. Serviceable hearing (Gardner-Robertson classes I-III) was found in 75% before and in 64.3% after surgery. CONCLUSIONPreservation of facial nerve and hearing function are not the only important criteria defining QOL after CPA surgery. Tinnitus and vertigo may have a significant underestimated impact on the patients postoperative course and QOL.

Use of Piezosurgery for removal of retrovertebral body osteophytes in anterior cervical discectomy.

BACKGROUND CONTEXT The relatively new technique of Piezosurgery is based on microvibrations, generated by the piezoelectrical effect, which results in selective bone cutting with preservation of adjacent soft tissue. PURPOSE To study the applicability of Piezosurgery in anterior cervical discectomy with fusion (ACDF) surgery. STUDY DESIGN/SETTING Prospective clinical study at the neurosurgical department of the University of Freiburg, Germany. PATIENT SAMPLE Nine patients with cervical disc herniation and retrovertebral osteophytes who underwent ACDF surgery. OUTCOME MEASURES Piezosurgery was evaluated with respect to practicability, safety, preciseness of bone cutting, and preservation of adjacent neurovascular tissue. Pre- and postoperative clinical and radiological data were assessed. METHODS Piezosurgery was supportively used in ACDF in nine patients with either radiculopathy or myelopathy from disc herniation or ventral osteophytes. After discectomy, osteophytes were removed with Piezosurgery to decompress the spinal canal and the foramina. Angled inserts were used, allowing for cutting even retrovertebral osteophytes. RESULTS In all nine cases, Piezosurgery cut bone selectively with no damage to nerve roots, dura, or posterior longitudinal ligament. None of the patients experienced any new neurological deficit after the operation. The handling of the instrument was safe and the cut precise. Osteophytic spurs, even retrovertebral ones that generally only can be approached via corpectomies, could be safely removed because of the angled inserts through the disc space. Currently, a slightly prolonged operation time was observed for Piezosurgery. Furthermore, the design of the handpiece could be further improved to facilitate the intraoperative handling in ACDF. CONCLUSIONS Piezosurgery proved to be a useful and safe technique for selective bone cutting and removal of osteophytes with preservation of neuronal and soft tissue in ACDF. In particular, the angled inserts were effective in cutting bone spurs behind the adjacent vertebra which cannot be reached with conventional rotating burs.

A Rare Case of Radiologically Not Distinguishable Coexistent Meningioma and Vestibular Schwannoma in the Cerebellopontine Angle - Case Report and Literature Review

Background: The simultaneous occurrence of cerebellopontine angle (CPA) meningioma and vestibular schwannoma (VS) in the absence of neurofibromatosis type 2 or history of irradiation is very rare. We report a case with coexistent CPA meningioma and VS, which were radiologically not distinguishable in preoperative imaging. Case Description: A 46-year-old female presented with acute hearing loss, tinnitus and gait ataxia. Otorhinolaryngological diagnostic workup and imaging studies showed an intra- and extrameatal homogenous contrast enhancing lesion. The neuroradiological diagnosis was VS. The patient was operated via the retrosigmoid approach. Intraoperatively two distinct tumors were found: a small, mainly intrameatally located VS and a larger meningioma originating from the dura of the petrous bone. Both tumors were completely microsurgically removed. The patient experienced no new neurological deficit after surgery; particularly facial nerve function was completely preserved. Histopathological examination revealed a fibromatous meningioma and a VS, respectively. Conclusions: The coincidental occurrence of CPA meningioma and VS is very rare. Careful interpretation of imaging studies before surgery is crucial. Even such rare cases should be kept in mind when discussing the therapeutic options with the patient. More studies are needed for a better understanding of mechanisms leading to multiple tumor growth.

Atypical meningioma: progression-free survival in 161 cases treated at our institution with surgery versus surgery and radiotherapy

Although atypical meningioma recurs frequently in spite of total resection and/or radiotherapy, no consensus on optimal adjuvant management was found. However, several retrospective studies analysed the additional effect of adjuvant radiotherapy in atypical meningioma with inconsistent results. Therefrom, the purpose of this study was to evaluate prognostic factors influencing the recurrence/progression and progression-free survival (PFS) rates of atypical meningioma, particularly focused on the role of postoperative adjuvant radiotherapy. Between February 2001 and March 2015, 161 atypical meningioma resections were performed in our Department of Neurosurgery, of which, 128 cases underwent surgical treatment alone and 33 cases underwent surgery and radiotherapy. Kaplan–Meier analysis was used to provide median point estimates and PFS rates. The Cox-regression model was used in the univariate and multivariate analysis to identify significant factors associated with treatment. The extent of resection (Simpson grade I and II) significantly influenced the risk of recurrence (hazard ratio = 1.8, CI (95%) 1.3–2.6, p-value = 0.0004). There was no significant benefit for progression-free survival after adjuvant radiotherapy (hazard ratio = 1.48, CI (95%) 0.76–2.86, p-value = 0.22). Additionally, meningioma located at the anterior and posterior fossa showed a significantly longer PFS compared to other locations (p-value = 0.03). Adjuvant postoperative radiotherapy had no significant impact on recurrence/progression rate or PFS. The extent of resection according to Simpson grade remains the most important prognostic factor associated with lower recurrence/progression rates and longer PFS in patients with atypical meningioma. The location of the tumours at the anterior or posterior fossa was an independent factor associated with improved PFS.

Navigation accuracy after automatic- and hybrid-surface registration in sinus and skull base surgery

Objective Computer-aided-surgery in ENT surgery is mainly used for sinus surgery but navigation accuracy still reaches its limits for skull base procedures. Knowledge of navigation accuracy in distinct anatomical regions is therefore mandatory. This study examined whether navigation accuracy can be improved in specific anatomical localizations by using hybrid registration technique. Study design Experimental phantom study. Setting Operating room. Subjects and methods The gold standard of screw registration was compared with automatic LED-mask-registration alone, and in combination with additional surface matching. 3D-printer-based skull models with individual fabricated silicone skin were used for the experiments. Overall navigation accuracy considering 26 target fiducials distributed over each skull was measured as well as the accuracy on selected anatomic localizations. Results Overall navigation accuracy was <1.0 mm in all cases, showing the significantly lowest values after screw registration (0.66 ± 0.08 mm), followed by hybrid registration (0.83± 0.08 mm), and sole mask registration (0.92 ± 0.13 mm).On selected anatomic localizations screw registration was significantly superior on the sphenoid sinus and on the internal auditory canal. However, mask registration showed significantly better accuracy results on the midface. Navigation accuracy on skull base localizations could be significantly improved by the combination of mask registration and additional surface matching. Conclusion Overall navigation accuracy gives no sufficient information regarding navigation accuracy in a distinct anatomic area. The non-invasive LED-mask-registration proved to be an alternative in clinical routine showing best accuracy results on the midface. For challenging skull base procedures a hybrid registration technique is recommendable which improves navigation accuracy significantly in this operating field. Invasive registration procedures are reserved for selected challenging skull base operations where the required high precision warrants the invasiveness.

Combined effects of chronic and acute ethanol on pancreatic injury and microcirculation.

Objectives Aim of the study was to investigate pancreatic microcirculatory and histopathological changes in rats after chronic ethanol liquid diet feeding. Methods To investigate the influence of chronic alcohol exposition (CAE) on the pancreas, rats were fed with either Lieber-DeCarli (LDC) control diet or LDC alcohol diet for 2, 4, or 6 weeks and received additionally an acute ethanol administration (AEA) for 90 minutes. Intravital microscopy was performed at baseline, 45 minutes, and 90 minutes after starting AEA. Pancreatic perfusion and leukocyte adhesion were assessed, and pancreatic damage was evaluated by histology. Results Capillary perfusion was reduced in all animals after AEA. After previous CAE, there was a significant increase in leukocyte adhesion compared to control groups (P < 0.05). Most importantly, leukocyte adhesions were already increased at baseline after CAE and before the acute bolus was infused (P < 0.05). Moreover, only animals that received LDC alcohol diet developed mild histological changes consisting of pancreatic edema and vacuoles, whereas those that received AEA alone did not. Histological changes and cytokine levels correlated with the duration of prior CAE. Conclusions Long-term alcohol intake activates endothelium and sensitizes the pancreas for inflammatory reactions leading to an increased likelihood of a clinically evident episode of acute pancreatitis.

Piezosurgery-, neuroendoscopy-, and neuronavigation-assisted intracranial approach for removal of a recurrent petrous apex cholesteatoma: technical note

Current approaches for resection of petrous bone cholesteatomas (PBCs), such as canal wall up (closed) and canal wall down (open) mastoidectomies, in the pediatric population present recurrence rates ranging between 17% and 70% with a high rate of postoperative complications involving hearing loss and facial nerve weakness. This technical note illustrates an alternative intracranial approach that was used in combination with the techniques of piezoelectric surgery, neuroendoscopy, and neuronavigation for safe and effective removal in a difficult pediatric case of recurrent PBC. The third recurrence of a PBC in a 14-year-old girl was diagnosed by CT and MRI. A retrosigmoid approach gave access to the petrous apex, allowing for the safe and complete removal of the lesion and decompression of the facial nerve and internal carotid artery. The intraoperative implementation of piezoelectric surgery, neuronavigation, neuroendoscopy, and neuromonitoring ensured better intraoperative visualization, safer bone removal, and preservation of nerve function, facilitating a macroscopically total resection of the pathology without additional neurological damage of the adjacent tissues. Cholesteatoma extension could be clearly verified by intraoperative neuronavigation. Neuroendoscopy and piezoelectric surgery provided good support in the safe bone removal in close vicinity to neurovascular structures and in full vision inside the cholesteatoma cavity beyond the line of sight of the microscope. Hearing and facial nerve function could be preserved. The presented intracranial retrosigmoid approach combined with multiple intraoperative assisting techniques proved to be effective for the safe and complete removal of recurrent PBC, providing excellent intraoperative visualization and the possibility of preserving cranial nerve function.

Piezosurgery in Modified Pterional Orbital Decompression Surgery in Graves Disease

OBJECTIVE Piezosurgery uses microvibrations to selectively cut bone, preserving the adjacent soft tissue. The present study evaluated the use of piezosurgery for bone removal in orbital decompression surgery in Graves disease via a modified pterional approach. METHODS A piezosurgical device (Piezosurgery medical) was used in 14 patients (20 orbits) with Graves disease who underwent orbital decompression surgery in additional to drills and rongeurs for bone removal of the lateral orbital wall and orbital roof. The practicability, benefits, and drawbacks of this technique in orbital decompression surgery were recorded. Piezosurgery was evaluated with respect to safety, preciseness of bone cutting, and preservation of the adjacent dura and periorbita. Preoperative and postoperative clinical outcome data were assessed. RESULTS The orbital decompression surgery was successful in all 20 orbits, with good clinical outcomes and no postoperative complications. Piezosurgery proved to be a safe tool, allowing selective bone cutting with no damage to the surrounding soft tissue structures. However, there were disadvantages concerning the intraoperative handling in the narrow space and the efficiency of bone removal was limited in the orbital decompression surgery compared with drills. CONCLUSIONS Piezosurgery proved to be a useful tool in bone removal for orbital decompression in Graves disease. It is safe and easy to perform, without any danger of damage to adjacent tissue because of its selective bone-cutting properties. Nonetheless, further development of the device is necessary to overcome the disadvantages in intraoperative handling and the reduced bone removal rate.

Piezosurgery—A Safe Technique to Perform Lateral Suboccipital Craniotomy?

BACKGROUND Piezosurgery (PS) is a relatively new technique based on microvibrations generated by the piezoelectric effect. It selectively cuts bone tissue and preserves the surrounding soft tissue. OBJECTIVE To evaluate the use of PS for performing lateral suboccipital craniotomy. METHODS PS was used to perform a lateral suboccipital craniotomy in 22 patients who underwent surgery for different cerebellopontine angle (CPA) pathologies in the neurosurgical department. The applicability of PS for lateral suboccipital craniotomy was evaluated with respect to safety, preciseness of bone cutting, and in particular the preservation of the adjacent dura and sigmoid and transverse sinuses. RESULTS Lateral suboccipital craniotomy in 22 patients who underwent surgery for different CPA pathologies (13 vestibular schwannoma, 5 petrous bone meningioma, 1 petroclival meningioma, 2 epidermoid cysts, and 1 petrous bone cholesterol granuloma) was performed with PS without any complications. A burr hole was set before piezosurgical craniotomy in 6 patients, with no prior burr hole in 16 patients. Incidental durotomy during piezosurgical craniotomy occurred in 6 patients, and small lacerations of the sigmoid sinus caused by the piezosurgical device were observed in 3 patients. CONCLUSION Although PS is a safe and selective bone cutting technique that preserves the surrounding soft tissue, it can still lead to unintended dural tears during lateral suboccipital craniotomy. This must be kept in mind when using PS for craniotomies and relying on the selective bone cutting properties of PS.