0000000000016815

AUTHOR

Axel Perneczky

Surgically verified variations in the A1 segment of the anterior cerebral artery

✓ Two patients with rare variations of the A1 segment of the anterior cerebral artery are presented. One patient had a perforation of the optic tract by an abnormal course of the A1 segment, and the other harbored an aneurysm of the A1 segment running below the optic nerve. The authors present a summary of A1 segment variations described in the literature.

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Die Blutverteilung im initialen kraniellen Computertomogramm im Hinblick auf die Entwicklung eines shuntpflichtigen Hydrozephalus nach akuter Subarachnoidalblutung

Als Folge einer akuten Subarachnoidalblutung kommt es nicht selten zum chronischen Hydrozephalus. Ziel der vorliegenden retrospektiven Arbeit war die Analyse des Zusammenhangs zwischen der Blutverteilung im initialen kraniellen Computertomogramm (CCT) und der spateren Entwicklung einer shuntpflichtigen Liquorzirkulationsstorung.

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Surgical technique of the supraorbital key-hole craniotomy.

BACKGROUND The enormous development of microsurgical techniques and instrumentation together with preoperative planning using the excellent preoperative diagnostic facilities available, enables neurosurgeons to treat more complicated diseases through smaller and more specific approaches. METHODS The technical details of the supraorbital key-hole craniotomy are described in this article as it has been evolving in our experience for more than 10 years. After an eyebrow skin incision with careful soft tissue dissection and single frontobasal burr-hole trephination, a supraorbital craniotomy is carried out with a diameter of about 1.5 x 2.5 cm. As a real frontolateral approach, the supraorbital…

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Bovine pericardium for duraplasty: clinical results in 32 patients.

Bovine pericardium has been widely used for grafts in cardiac surgery and seems to have suitable properties for use as a dural graft. We report on the use of solvent-preserved, gamma-sterilized Tutoplast bovine pericardium for dural grafts in 32 patients undergoing cranial and spinal operations with the objective of clinically assessing this material and technique by a retrospective analysis. All available records were reviewed and information regarding the indication for grafting, complications, and outcome were collected and analyzed for all patients. Indications for grafting included tethered cord myelolysis, closure of lumbosacral myeloceles, Chiari decompression, posterior fossa cranio…

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Intraoperative Topographische Diagnostik bei kortikalen Tumoren in der Sprach- und Zentralregion

Exstirpation von kortexnahen Tumoren in der Sprach- und Zentralregion birgt die Gefahr einer postoperativen neurologischen Verschlechterung. Intraoperativ ist die rein anatomisch topographische Planung des Zuganges nicht ausreichend, um diese Kortexareale funktionell genau zu lokalisieren und auszusparen. Aus diesem Grund erscheint es wichtig, wahrend der Operation die sprachrelevanten Areale sowie die fur die Motorik essentiellen kortikalen Bereiche exakt zu lokalisieren und ihre Ausdehnung zu bestimmen. Dies kann durch elektrische Stimulation des Kortex unmittelbar nach der Eroffnung der Dura mater erfolgen. Bei Eingriffen in der Sprachregion mus berucksichtigt werden, das die Uberprufung…

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Brain Oedema and Intracranial Pressure in Superior Sagittal Sinus Balloon Occlusion. An Experimental Study in Pigs

About 2/3 of all patients with thrombosis of the superior sagittal sinus (SSS) develop signs of increased ICP and/or brain oedema (BE). The time of onset and the spectrum of symptoms in SSS thrombosis vary extremely. This variability might be caused by differences in pathomechanism like BE and rise of ICP, parameters studied in the present contribution.

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Postoperative pain therapy after lumbar disc surgery.

Object. This study was undertaken to determine whether a special postoperative pain administration of tramadol and diclofenac provides any benefits in patients who underwent microsurgical lumbar discectomy.  Methods. The study consisted of 60 patients undergoing microsurgical lumbar discectomy. Patients were randomly divided into two groups based on the postoperative pain management: 1) Group A (n=30): no standardized pain therapy; these patients received on demand different analgesics and at variable dosages which were selected by the neurosurgeons; 2) Group B (n=30): standardized pain therapy with specific dosages of tramadol and diclofenac in regular time intervals during the first 48 ho…

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Endoscope-assisted Brain Surgery: Part 1—Evolution, Basic Concept, and Current Technique

Rationale The evolution of neurosurgical techniques indicates the effort to reduce surgery-related traumatization of patients. The reduction of traumatization contributes to better postoperative outcomes. The improvement of diagnostic imaging techniques facilitates not only the precise localization of lesions but also the accurate determination of topographical relations of specific lesions to individual anatomic variations of intracranial structures. This precision of diagnostic imaging should be used to perform individual surgical procedures through so-called keyhole approaches. Keyhole craniotomies are afflicted with a reduction of light intensity in the depth of the operating field, and…

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Enhanced Interleukin-1β Release and Longevity of Glioma-associated Peripheral Blood Monocytes in Vitro

Interleukin-1 (IL-1) plays a controversial role in the immune response. Besides its activation of immune cells and juvenile central nervous system cells, monocyte-derived IL-1 may be able to stimulate the malignant transformation and proliferation of glial brain tumor cells expressing IL-1 receptors. The aim of this study was to determine the growth pattern and the IL-1 beta release of long-term cultured peripheral blood monocytes of glioma patients. At 6- to 7-day intervals, the vital monocytes, characterized by CD14 immunophenotyping, were counted. By the use of a specific IL-1 beta enzyme-linked immunosorbent assay, the IL-1 beta content of monocyte culture supernatants derived from 13 s…

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Brain tissue pO2 related to SjvO2, ICP, and CPP in severe brain injury

The aim of this report is to present first experience in comparing the course of brain tissue oxygen pressure values (PtiO2) to changes in jugular vein oxygen saturation (SjvO2), intracranial pressure (ICP), and cerebral perfusion pressure (CPP) after severe brain injury. PtiO2 monitoring was done using a polarographic Clark type microcatheter (LICOX pO2 probe) (GMS, Kiel, Germany) with a diameter of 0.5 mm and a sensitive area 7.9 mm long inserted in a right frontal position. The microcatheter was connected to a LICOX pO2 device. A fiber-optic catheter was used to measure SjvO2 and placed into the right internal jugular vein. The ICP monitoring was performed with a fiber-optic intraparench…

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MGMT in primary and recurrent human glioblastomas after radiation and chemotherapy and comparison with p53 status and clinical outcome

The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) plays a pivotal role in alkylating drug resistance. Here, we determined MGMT activity in primary and recurrent glioblastomas (GBM, WHO grade IV) of patients who received radiation therapy (RT) or RT plus chemotherapy with alkylating agents (temozolomide, chloroethylnitrosoureas). The mean MGMT activity of untreated GBM was 37 +/- 45 (range 0-205) fmol/mg proteins. In the 1st, 2nd and 3rd recurrences, MGMT activity increased from 66 +/- 50 (13-194) to 68 +/- 44 (14-143) and 182 +/- 163 (64-423) fmol/mg protein, respectively. Comparing patients who received RT only with RT plus chemotherapy, a significant increase of MGMT …

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Transcranial Doppler diagnosis of cerebral vasospasm following subarachnoid haemorrhage: correlation and analysis of results in relation to the age of patients.

A retrospective analysis was undertaken to determine whether cerebral vasospasm following subarachnoid haemorrhage (SAH) correlates with the age of patients. For at least 3 weeks after bleeding 80 subjects underwent very close follow-up with clinical examination and transcranial Doppler records of the blood velocities within the basal cerebral arteries. Firstly a correlation between measured maximal mean blood flow velocities and age was made. Secondly, according to their age and the maximum of recorded mean velocities (v), the patients were divided into groups as follows: age 55 years or less, age more than 55 years; and maximum velocity v190 cm/s, 90 cm/sv2120 cm/s, 120 cm/sv3160 cm/s, v4…

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TUMORS OF THE LATERAL AND THIRD VENTRICLE

Abstract OBJECTIVE: Intraventricular tumors usually are managed by approaches and microsurgical techniques that need retraction and dissection of important brain structures. Minimally invasive endoscopic procedures achieve a remarkable alternative to conventional microneurosurgical techniques. Endoscope-assisted microneurosurgery may be a minimally invasive technique with maximally effective treatment. Using the keyhole concept for planning the surgical strategy, the reduction of the brain retraction is achieved, which is one of the main benefits of this technique. METHODS: We treated 35 patients (16 female patients and 19 male patients) with tumors in the lateral (n = 8) and the third (n =…

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Histological Findings in Coil-packed Experimental Aneurysms 3 Months after Embolization

ABSTRACT OBJECTIVE Knowledge regarding tissue reactions within coil-packed aneurysms is poor. The purpose of this study was to analyze histological changes in a chronic experimental bifurcation aneurysm model that might explain the protective effect of Guglielmi detachable coils. METHODS The aneurysms were produced by means of a venous graft pouch at a surgically created bifurcation of the carotid artery in the neck of rabbits. After 3 weeks, embolization with Guglielmi detachable coils was performed in the treatment group but not in the control group (seven rabbits each). At the time of embolization, six of seven treated aneurysms were completely occluded according to radiological criteria…

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Multimodal user interface for a semi-robotic visual assistance system for image guided neurosurgery

Abstract We developed a visual assistance system for image guided neurosurgery, consisting of a stereoscopic digital camera (exoscope) mounted on a semi-robotic manipulator. In order to minimize the operation time, the application-specific multimodal user interface enables hands-free manipulation of the exoscope. The surgeon wears thereby a head-mounted unit with a binocular display, a head tracker, a microphone and earphones. Different modes of view positioning and adjustment can be selected by voice and controlled by head rotation while pressing a miniature confirmation button mounted on a finger ring or suction device. Apart from the development of the mechatronic and software modules of…

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Mesencephalic ependymal cysts: treatment under pure endoscopic or endoscope–assisted keyhole conditions

Object Primary intracranial ependymal cysts are extremely rare. Similar to congenital intraparenchymal cysts in the mesencephalon they usually occur with symptoms of an occlusive hydrocephalus or symptoms like Parinaud syndrome, dizziness, or gait disturbance. The objective of this study was to evaluate the surgical methods for the treatment of these cysts and the clinical outcome of the patients. Methods The authors present the clinical records of 8 patients who were treated in their department for symptomatic mesencephalic ependymal cysts in the past 10 years. The patient age ranged from 22 to 60 years with a mean age of 44 years. In 4 cases the authors performed a suboccipital infratent…

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New method of bone reconstruction designed for skull base surgery

The direct endonasal or transoral transclival approaches to the skull base permit effective, minimally invasive surgery along the clivus. Developing long-term, effective techniques to prevent cerebrospinal fluid (CSF) leaks and their consequences (infection and delayed healing) remains a major challenge. In this study we describe a method of bone reconstruction newly developed by us, which uses a custom designed silicone plug for bone replacement after minimally invasive skull base surgery with a low incidence of postoperative CSF leaks. German Landrace pigs were used to test the efficiency of the new technique. Twelve craniotomies were performed in six pigs using a subtemporal approach and…

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Neuroendoscopic Technique for the Operative Treatment of Septated Syringomyelia

The management of septated, chambered syringomyelia has until now been problematic because the usual operative methods cannot secure drainage of all chambers of the cavity.

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Tightness of duraplasty in rabbits: a comparative study.

OBJECTIVE: The purpose of this study was to test, in rabbits, the tightness of seven dural substitution materials commonly used in neurosurgery, i.e., Lyodura (B. Braun Melsungen AG, Melsungen, Germany), Tutoplast dura (Tutogen Medical, Inc., Parsippany, NJ), Tutoplast fascia lata (Tutogen Medical, Inc.), autologous periosteum, Neuropatch (B. Braun Melsungen AG), Dacron (E.I. du Pont de Nemours and Co., Wilmington, DE), and Ethisorb (Ethicon, Inc., Somerville, NJ). METHODS: Duraplasties were performed with sutures alone or were additionally fixed with fibrin glue. Leakage pressures were assessed by infusion of artificial cerebrospinal fluid, containing sodium fluorescein, into the cisterna …

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Contralateral and ipsilateral microsurgical approaches to carotid-ophthalmic aneurysms.

Objective The vicinity of carotid-ophthalmic aneurysms to the roof of the cavernous sinus, to the anterior clinoid process, and to the optic nerve or the optic chiasm requires well-defined surgical techniques. Although microsurgical techniques with ipsilateral direct approaches to these aneurysms have been described in detail, studies about contralateral strategies for the microsurgical treatment of carotid-ophthalmic aneurysms are rare and are mainly confined to case reports. The aim of this study is to describe how to decide on the ipsilateral and contralateral microsurgical approaches to such aneurysms and to demonstrate the surgical techniques for the ipsilateral and contralateral expos…

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Cerebral blood flow velocities after subarachnoid haemorrhage in relation to the amount of blood clots in the initial computed tomography.

In 72 patients with acute subarachnoid haemorrhage (SAH) the relationship between the amount of subarachnoid blood clots detected by initial cranial computed tomography (CCT) up to 48 hours after bleeding and the later development of vasospasm, established by blood flow velocity measurement with transcranial Doppler ultrasound (TCD) was investigated. The serial Doppler examinations started within the first 72 hours after SAH and were carried out every second day up to three weeks. Each Doppler recording was accompanied by a neurological examination. Patients classified as Hunt and Hess grade V were excluded from the study. All patients with remarkable brain oedema in CCT or with intracrania…

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A COLLABORATIVE VIRTUAL REALITY ENVIRONMENT FOR NEUROSURGICAL PLANNING AND TRAINING

OBJECTIVE We have developed a highly interactive virtual environment that enables collaborative examination of stereoscopic three-dimensional (3-D) medical imaging data for planning, discussing, or teaching neurosurgical approaches and strategies. MATERIALS AND METHODS The system consists of an interactive console with which the user manipulates 3-D data using hand-held and tracked devices within a 3-D virtual workspace and a stereoscopic projection system. The projection system displays the 3-D data on a large screen while the user is working with it. This setup allows users to interact intuitively with complex 3-D data while sharing this information with a larger audience. RESULTS We have…

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Ten-year Experience with the Supraorbital Subfrontal Approach through an Eyebrow Skin Incision

Abstract OBJECTIVE: More than ever before, the priority in contemporary neurosurgery is to achieve the greatest therapeutic effect while causing the least iatrogenic injury. The evolution of microsurgical techniques with refined instrumentation and illumination and the enormous development of preoperative and intraoperative diagnostic tools enable neurosurgeons to treat different lesions through limited and specific keyhole approaches. METHODS: Based on our surgical experience, the technique of supraorbital subfrontal craniotomy is described in detail in this article. After an eyebrow skin incision is made, a limited supraorbital craniotomy is performed with a width of 15 to 25 mm and a hei…

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Effect of Intra-Arterial Infusion of Papaverine Hydrochloride on Brain Tissue Oxygen Pressure in the Management of Severe Vasospasm Following Aneurysmal Subarachnoid Hemorrhage

Despite considerable advances in diagnostic, surgical and interventional techniques, the overall outcome for patients with aneurysmal subarachnoid hemorrhage remains poor. Concerning perioperative course, cerebral ischaemia is one of the major factors causing secondary brain demage. The aim of all therapeutic interventions is the stabilization and maintance of cerebral blood flow and tissue oxygenation in order to prevent cerebral ischaemia and consecutively brain infarction [1].

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Occlusion of the pig superior sagittal sinus, bridging and cortical veins: multistep evolution of sinus-vein thrombosis

✓ Cerebral sinus-vein thrombosis may lead to severe hemodynamic changes, elevated intracranial pressure (ICP), and brain edema. It is supposed that progression of the thrombus from the sinus into bridging and cortical veins plays a key role in the development of these pathophysiological changes, but this hypothesis lacks experimental proof. The aim of this study, using a novel animal model of sinus-vein thrombosis, was to evaluate the effects of a standardized occlusion of the superior sagittal sinus and its bridging and cortical veins on hemodynamic alterations, on brain water content, and on ICP in domestic pigs. In 10 animals, the middle third of the superior sagittal sinus was occluded …

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The influence of surgical experience on the rate of intraoperative aneurysm repture and its impact on aneurysm treatment outcome.

Abstract BACKGROUND The influence of surgical experience on the result of aneurysm surgery remains unclear. To determine the impact of surgical experience we considered the occurrence of intraoperative aneurysm rupture (IAR) during microneurosurgery for intracranial aneurysms as an objective factor that could be evaluated. METHODS A retrospective study was performed on 379 consecutive patients with 490 cerebral aneurysms operated upon from 1989 to 1995. RESULTS IAR occurred in 6.7% of aneurysms and 8.7% of patients. There was a direct inverse relationship between the annual caseload of the surgeon and the risk of IAR. New neurological deficits (NND) occurred in 21% of patients with IAR, whi…

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Endoscopic Treatment of Mesencephalic Ependymal Cysts: Technical Case Report

OBJECTIVE: To evaluate the results of different neuroendoscopic surgical procedures for the treatment of mesencephalic ependymal cysts. METHODS: The clinical records of five patients treated for symptomatic mesencephalic ependymal cysts were retrospectively studied. Two patients had been operated on using an endoscope-assisted microsurgical technique and three patients using a pure endoscopic procedure. RESULTS: Adequate fenestration of the cysts was achieved in all of the patients. Two of the patients were symptom-free, and the other three had improved significantly after a mean follow-up duration of 14 months. There was no surgical morbidity. CONCLUSION: Mesencephalic ependymal cysts can …

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CT-guided stereotactic biopsy aided by Doppler ultrasonic vascular monitoring

The use of a 20 MHz pulsed Doppler technique during stereotactic brain tumour biopsies is described. By means of a miniaturized ultrasonic probe the tissue planned for biopsy was investigated for vessel signals. Out of 41 patients, with this technique a flow-pulse curve in front of the biopsy cannula was registered in 14 cases. In 9 cases one pulse curve was determined and in 5 cases two or more flow curves were found, indicating the presence of arterial vessels. The depth of the vessels signal could be localized and this area avoided for biopsy sampling. In a series of 41 stereotactic biopsies carried out in this way there was no intra-operative haemorrhage or postoperative haematoma.

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Endoscopy in aneurysm surgery.

BACKGROUND: Surgical clipping with complete occlusion of the aneurysm and preservation of parent, branching, and perforating vessels remains the most definitive treatment for intracranial aneurysms. OBJECTIVE: To evaluate the benefit of endoscopic application during microsurgical procedures in a retrospective study. METHODS: One hundred eighty aneurysms were microsurgically treated in 124 operations. Three different applications of endoscopic visualization were used, depending on the respective requirements: inspection before clipping, clipping under endoscopic view, and postclipping evaluation. RESULTS: Of 1380 aneurysms, 292 procedures were done with application of the endoscope. Of these…

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Endoscope-assisted Brain Surgery: Part 2—Analysis of 380 Procedures

Objectives Microsurgical techniques and instruments that help to reduce intraoperative retraction of normal intracranial neuronal and vascular structures contribute to improved postoperative results. To achieve sufficient control of the operating field without retraction of neurovascular components, the resection of dura and bone edges is frequently required, which, on the other hand, increases operating time and operation-related trauma. The use of endoscopes may help to reduce retraction and, at the same time, may help to avoid additional dura and bone resection. The aim of this study is to describe the principles on which the technique of endoscope-assisted brain surgery is based, to giv…

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Endoscopic aqueductoplasty through a tailored craniocervical approach.

Object. Neuroendoscopy has an essential role in the management of occlusive hydrocephalus due to a membranous obstruction of the sylvian aqueduct. Well-known endoscopic methods include endoscopic third ventriculostomy (ETV) and endoscopic aqueductoplasty through a frontal burr hole. Building on their experience in the endoscopic management of hydrocephalus, the authors realized that not all of their patients with aqueductal obstruction were eligible for the aforementioned lines of treatment. Certain anatomical situations made it impossible to perform ETV or endoscopic aqueductoplasty through a frontal burr hole. Long-term complications of the shunt system led the authors to seek an alternat…

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Primary myelomeningocele closure and consequences

Myelomeningocele, the most frequently occurring open neural tube defect, requires lifelong care of the patient by medical professionals and by relatives. A basic understanding of the neurosurgical measures that have to be taken in the newborn, the infant, the child and the adult is important also for physicians of other disciplines involved in the treatment of patients with myelomeningocele.The most recent topic broadly discussed in this context is the role of foetal neurosurgery for closure of the neural tube defect. There is ongoing debate as to whether the beneficial postnatal effects of a prenatal operation in the unborn foetus outweighs the possible complications for the mother as well…

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Virtual reality system for planning minimally invasive neurosurgery

Object The authors report on their experience with a 3D virtual reality system for planning minimally invasive neurosurgical procedures. Methods Between October 2002 and April 2006, the authors used the Dextroscope (Volume Interactions, Ltd.) to plan neurosurgical procedures in 106 patients, including 100 with intracranial and 6 with spinal lesions. The planning was performed 1 to 3 days preoperatively, and in 12 cases, 3D prints of the planning procedure were taken into the operating room. A questionnaire was completed by the neurosurgeon after the planning procedure. Results After a short period of acclimatization, the system proved easy to operate and is currently used routinely for pre…

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Suprasellar Granular Cell Tumor

A case of a suprasellar granular cell tumor, approximately 1.5 cm in diameter, in a 68-year-old woman is described. Diagnosis was established postoperatively by histopathological examination of the tumor tissue. The preoperative computed tomographic scan revealed a slightly hyperdense suprasellar mass with strong contrast enhancement. There was no evidence of calcification. The T1-weighted image on magnetic resonance imaging scan showed an isointense tumor with non-homogeneous enhancement after intravenous gadolinium diethylene-triamine-pentaacetic acid. In the proton-weighted image, the suprasellar mass presented a non-homogeneously enhanced signal. A non-homogeneous signal reduction was s…

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The keyhole concept in aneurysm surgery: results of the past 20 years.

Item does not contain fulltext BACKGROUND: Improvements in preoperative imaging and intraoperative visualization have led to a refinement in surgical techniques. OBJECTIVE: Report of a 20-year experience with application of the keyhole technique as a contribution to the ongoing debate on the impact of limited craniotomies in aneurysm surgery. METHODS: Over a 20-year period, 1000 consecutive patients with 1297 aneurysms were surgically treated in 1062 operations: 651 in the acute stage after SAH and 411 with unruptured aneurysms. The outcome was assessed with the modified Rankin scale and approach-related complications. RESULTS: The majority of the cases were treated by 4 different keyhole a…

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Sensitivity and specificity of MRA in the diagnosis of neurovascular compression in patients with trigeminal neuralgia

The published rates of operatively confirmed neurovascular compression as the cause for trigeminal neuralgia range from 10 % to nearly 100 %. High-definition magnetic resonance angiography (MRA) was performed in 27 consecutive patients (in 6 cases with 3D reconstructions) to show neurovascular compression preoperatively. The MRA findings were compared with the relationship between the Vth nerve and the surrounding vessels at surgery. In 23 patients MRA showed present neurovascular compression in accordance with surgical findings (18/27 in complete accordance of type and side of vessel, site and direction of compression). One woman had no neurovascular compression either on MRA or intraopera…

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Pre- and intraoperative methods of controlling cerebral circulation in giant aneurysm surgery.

The surgical treatment of giant aneurysms usually requires temporary clipping of the aneurysmatic vessel. In planning the surgical approach and in applying temporary clips, the surgeon must consider collateral circulations. The functional integrity of the collateral vessels frequently decides the patient's outcome. In 8 patients with internal carotid artery giant aneurysm, measurements of blood flow velocities in the ipsilateral middle cerebral artery were performed preoperatively with transcranial Doppler ultrasound (TCD) during manual occlusion of the carotid artery at the neck. Three different perfusion patterns were established, and each collateral capacity was rated as insufficient, te…

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The Role of Endoscopy in the Treatment of Acute Traumatic Anterior Epidural Hematoma of the Cervical Spine: Case Report

OBJECTIVE AND IMPORTANCE: Epidural hematoma (EDH) of the spine represents an uncommon neurosurgical disorder that sometimes requ;res emergent surgical decompressive therapy. Traumatic EDH of the cervical spine is exceedingly rare. The hematoma is usually located dorsally in the epidural space. We present one case of acute EDH located ventrally in the cervical spine. Special emphasis is placed on the role of spinal endoscopy in surgical treatment. CLINICAL PRESENTATION: After a fall from a tree, a 69-year-old man with rapidly increasing tetraparesis was referred to our institution. Plain films of the cervical spine revealed nothing abnormal. The results of computed tomography were highly sus…

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Endoscope-assisted keyhole surgery for aneurysms of the anterior circulation and the basilar apex

In the treatment of cerebral aneurysms, preoperative surgical planning and intraoperative strategies for microsurgical approaches are important issues. Within the context of minimally invasive neurosurgery, so-called keyhole approaches, especially those with intraoperative endoscopic assistance, have gained increasing interest, but their application for cerebral aneurysm surgery is a matter of ongoing controversy. The main aspects of keyhole microsurgery, with and without endoscopic assistance, for cerebral aneurysms are explained. To present the keyhole concept, which is based on the preoperative analysis and intraoperative use of pre-existing anatomic windows, this article concentrates on…

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Aneurysm surgery of patients in poor grade condition. Indications and experience

Out of a total of 196 patients admitted with aneurysmal subarachnoid haemorrhage (SAH) to the neurological department in Mainz over a 42 month period, 48 patients (24.5%) were considered as grade IV or V on admission. Aneurysm surgery within 48 hours after SAH was performed in 56.3% of these patients, 2% were operated between day 3 and 7 and 16.6% were operated after day 7. 25% did not undergo operation because of severe neurological deficit and brain damage. The overall outcome according to the Glasgow outcome scale in the surgically treated group was full recovery in 11.1%, moderate disability in 16.7%, severe disability in 47.2%, vegetative state in 2.8% and death in 22.2%. All patients …

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Endoscopic Neurosurgery and Endoscope-assisted Microneurosurgery for the Treatment of Intracranial Cysts

Objective Different endoscopic techniques have been introduced into neurosurgery, but accepted terminology and definitions are still missing. We propose a terminology based on whether the endoscope is used alone or in conjunction with an operating microscope and on whether the route of surgical manipulations is through or outside the endoscope. Accordingly, procedures are categorized into endoscopic neurosurgery (EN), endoscope-assisted microneurosurgery (EAM), and endoscope-controlled microneurosurgery (ECM). Methods We treated 36 patients with intracranial arachnoid cysts (ACs) and intraventricular cysts endoscopically. The patients ranged in age from 4 months to 69 years (mean age, 31 yr…

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Endoscope-assisted Craniotomy

We describe a surgical technique to improve visualization of deep brain structures during craniotomy. The technique, developed in a cadaveric model, combines the use of an operating microscope and a solid-rod lens endoscope. Addition of the endoscope during craniotomy allows the operator to visualize structures that otherwise might not have been seen. An approach to the brain stem is demonstrated.

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Evaluation of collateral flow capacity in patients with vascular or tumorous lesions of the skull base by Doppler sonography

In 12 patients with vascular or tumorous lesions of the skull base, the collateral flow capacity was examined by transcranial Doppler sonography and carotid compression studies. In four patients no cross flow mechanism was found, in two patients the test remained unclear, and in six patients the examination suggested a good collateral flow capacity. However, for this application of Doppler sonography no borderlines have yet been defined and thus interpretation is difficult. Intraoperative Doppler sonography was used in five patients and proved to be helpful for localisation of the internal carotid artery within skull base tumors.

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Endoscope-assisted microsurgery for cerebral aneurysms.

A total of 66 patients with intracranial aneurysms were endoscopically assisted treated during a 3 years period. Among those were five individuals with giant aneurysms and 27 patients with aneurysms of the posterior circulation. The endoscope was used only for checking the anatomical structures surround the aneurysms in 16 cases. In 43 patients the aneurysm sac was also dissected under endoscopical con-trol. Even the clipping procedure was performed in seven cases exclusively under endoscopical obser-vation. Only one prematural rupture occurred intraoperatively during preparation of a basilar tip aneurysm. Postoperatively three individuals with aneurysms located in the posterior circulation…

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Surgical complications after endoscopic transsphenoidal pituitary surgery.

Between January 2004 and June 2007 we conducted a retrospective analysis to assess post-operative complications related to endoscopic pituitary surgery in a series of 150 patients. Patients were treated with an endoscopic endonasal transsphenoidal approach to the sellar region for removal of pathological sellar and suprasellar lesions. We analysed the complications in groups according to the anatomical structures of the approach and the functional systems of the pituitary gland (anterior and posterior endocrine systems), and compared them to a large historical series using the traditional microsurgical transsphenoidal approach. Overall, we observed a decreased incidence of complications wit…

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Real and simulated endoscopy of neurosurgical approaches in an anatomical model

Endoscopy simulation is a new visualisation technique which can be used to visualise patient anatomy as seen through endoscopes. In the following, we describe the application of simulated endoscopy to neurosurgical endoscopic approaches. We assess different aspects of virtual images and their influence on the final result, as judged by clinicians. One of these aspects is the projective geometry which is used to render the 3D images. Rendering using stereographic projection leads to more realistic endoscopic views than perspective projection.

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Meningiomas of the Space of the Cavernous Sinus

During the years 1985 to 1992, we encountered 59 patients with meningiomas involving the space of the cavernous sinus. In 29 of these patients, meningiomas were primarily located within the space of the cavernous sinus and were operated on without mortality and with low morbidity. A small subtemporal surgical approach was favored, which allowed initial tumor resection from the posterior aspect, where the Parkinson's triangle is wide, thus avoiding the additional morbidity of large-scale approaches. According to the relationships of the all-important cranial nerves passing within the lateral wall of the cavernous sinus, we divided the primary intracavernous meningiomas into four types, which…

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Vascular Decompression of Trigeminal and Facial Nerves in the Posterior Fossa under Endoscope-Assisted Keyhole Conditions

Objective: The aim of this study was to determine the use and safety of the endoscope as an adjunct during trigeminal and facial nerve decompression procedures performed under keyhole conditions in the posterior fossa. Method: We performed 67 surgeries in 65 patients with symptomatic trigeminal and facial nerve compression syndromes. The diagnosis was made mainly on the basis of clinical history, examination, and magnetic resonance imaging scans. Surgery was performed in all cases under endoscope-assisted keyhole conditions. The follow-up was 1 week postoperatively, 6 months, and then yearly up to 7 years. All 34 patients with trigeminal neuralgia received preoperative medication treatment …

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Transoral transclival removal of anteriorly placed cavernous malformations of the brainstem.

BACKGROUND The natural history of brain stem cavernous malformations is unfavorable because of their high hemorrhage rate and resulting neurological deterioration among patients. However, direct surgery of intrinsic and anteriorly situated cavernomas is hazardous and leads to a bad postoperative outcome because of trauma to lateral and dorsally situated eloquent areas of the brain stem. METHODS We review the cases of two patients with symptomatic cavernous malformations of the anterior brain stem and describe the usefulness of a transoral-transclival approach. A 23-year-old man developed progressive hemihypaesthesia and paraesthesia, hemiparesis with gait ataxia, dysarthria, dysphonia, and …

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Endoscopic Third Ventriculostomy: Outcome Analysis of 100 Consecutive Procedures

OBJECTIVE: Endoscopic third ventriculostomy (ETV) has been shown to be a sufficient alternative in the surgical treatment of occlusive hydrocephalus. To elucidate the ongoing discussion of timing, indication, and surgical technique, a retrospective analysis of 100 consecutive ETVs was conducted. METHODS: One hundred ETVs were performed in 95 patients (43 female and 52 male patients). Their age ranged from 3 weeks to 77 years (mean age, 36 yr). Hydrocephalus was caused by aqueductal stenosis in 40 patients, space-occupying lesions in 42, and intraventricular or subarachnoid hemorrhage in 8. One patient had postinflammatory hydrocephalus, and four patients had occlusive hydrocephalus of unkno…

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Image Analysis of Proliferating Cells in Tumors of the Human Nervous System

Obtaining growth fractions from immunohistological preparations by the commonly used cell count calculation method is time consuming. For the first time, we investigated and compared the detection of proliferating cells in immunohistologically labeled tissue from tumors of the nervous system using the monoclonal antibody Ki-67 by a new computerized image analysis system and by cell count calculation. The two methods showed a high correlation (correlation index, 0.98) in 37 gliomas (2 pilocytic astrocytomas, 10 Grade II astrocytomas, 5 Grade III astrocytomas, 20 Grade IV astrocytomas and glioblastoma multiforme) and a heterogenous group of 10 additional tumors of the nervous system, includin…

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Subtemporal Keyhole Approach to the Suprasellar and Petroclival Region: Microanatomic Considerations and Clinical Application

OBJECTIVE: To minimize surgical invasiveness, the keyhole concept is applied to the subtemporal approach. METHODS: Anatomic features were studied in 14 sides of adult cadaver heads, and the technique was used in 162 interventions. Although most of the lesions treated were 3 cm in size or smaller, larger lesions were also treated using this technique. In some cases, if needed, an endoscope-assisted microsurgical technique was used. RESULTS: The cadaveric study provided intimate experience with the microsurgical anatomy of the approach. The 162 consecutive patients who were operated on harbored various types of lesions; the most recent 43 consecutive interventions were investigated in detail.…

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Combined Endo- and Exoscopic Semi-robotic Manipulator System for Image Guided Operations

This paper describes the development of a robotic assistance system for image guided operations. To minimize operation time, a multimodal user interface enables freehand robotic manipulation of an extracorporeal stereoscopic digital camera (exoscope) and an endoscope. The surgeon thereby wears a head-mounted unit with a binocular display, a head tracker, a microphone and earphones. Different view positioning and adjustment modes can be selected by voice and controlled by head rotation while pressing a miniature confirmation button with a finger. Initial studies focused on the evaluation and optimization of the intuitiveness, comfort and precision of different modes of operation, including a…

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Endoscopic Anatomy of the Ventricles

The endoscopic view offers a new anatomical dimension to the neurosurgeon. The fact makes it basically necessary to study the topographic anatomy under endoscopic conditions. In this paper attention was drawn to the ventricles because they are the most common region of clinical application. In 25 specimens neuroendoscopic explorations of the ventricles have been done. The dissections have been carried out through one- and two burr hole approaches (two working endoscopes at the same time). The instrumentation includes rigid 4 mm and 6 mm endoscopes. The procedures have been documented by continuous video recording and parallel photography.

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Use of a new aneurysm clip with an inverted-spring mechanism to facilitate visual control during clip application. Technical note.

✓ When operating on deep-seated cerebral aneurysms, the surgeon's visual control of clip application may be impaired by the clip holder unless adjacent structures are retracted. To improve visual control and reduce the necessity for retraction, the senior author (A.P.) developed a new concept: an aneurysm clip with an inverted-spring mechanism. The clip has two jaws that point away from the clip blades. The jaws of the clip holder articulate with the inner side of the clip jaws. By distending the jaws of the clip holder the blades of the clip are opened and vice versa. Thus the visual field increases while the clip application is proceeding. This instrumentation is useful, especially in cas…

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Amyloidoma of the gasserian ganglion as a cause of symptomatic neuralgia of the trigeminal nerve: report of three cases.

Three cases of symptomatic neuralgia of the trigeminal nerve due to an amyloidoma in the gasserian ganglion are described. The correct diagnosis was not made prior to histological examination of the surgical biopsy specimens. Medical history and clinical observation led to the diagnosis of a malignant process of the nasal cavities in the first patient; of an inflammatory dental focus in the second patient; and of multiple sclerosis in the third patient. CT findings were normal in cases 1 and 2; in case 3, a schwannoma was suspected from the CT appearances. In case 1, MRI had not been performed; in cases 2 and 3, MRI revealed a tumour mass which was also considered to be a schwannoma. Histol…

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Glioblastoma-associated circulating monocytes and the release of epidermal growth factor.

✓ Monocytes/macrophages frequently infiltrate malignant gliomas and play a central role in the tumor-associated immune response as they process tumor antigen and present it to T-lymphocytes. Findings have accumulated that peripheral blood monocytes leaving the cerebral circulation become microglial cells and vice versa and that monocytes/macrophages may stimulate malignant tumor growth by some unknown mechanism. Most malignant gliomas express growth factor receptors, for example epidermal growth factor receptor (EGFR). The aim of this study was to determine whether peripheral blood monocytes of glioma patients release EGF, the appropriate ligand of gliomacell membrane-bound EGFR. Long-term …

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Treatment results of acromegaly as analyzed by different criteria.

Results of treatment of acromegaly are often incomparable due to the different criteria which have been used for defining cure or control of disease. At the present time it is widely accepted, that the main criteria of cure must be normalization of IGF-1 and a GH in the OGTT2 ng/ml. In this retrospective study we investigated the endocrinological results of 56 patients, who were surgically treated because of a GH-producing pituitary adenoma, by different criteria. Twelve of our patients had had additional medical treatment after surgery, two received radiotherapy. At a mean follow-up of 34 months after surgery 66% of patients had a basal GH5 ng/ml, 64% had a GH in the OGTT2 ng/ml and 73% ha…

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Endoscope-assisted microsurgery for tumors of the septum pellucidum: surgical considerations and benefits of the method in the treatment of four serial cases

Neoplasms that primarily originate from the septum pellucidum are extremely rare. Generally the septum pellucidum is involved in direct extension of tumors that arise from the neighboring structures, principally the corpus callosum. Endoscope-assisted techniques form a useful adjunct to common microsurgical procedures to completely remove intraventricular lesions. There are two main advantages of endoscope-assisted surgery over common microsurgical techniques: reduction of superficial brain retraction with less iatrogenic trauma to the neighboring structures and inspection of hidden corners depict simultaneously anatomical details which are not precisely visible in the zoomed and thus light…

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Endoscopic endonasal pituitary surgery: Surgical and outcome analysis of 50 cases

Abstract Objective Microsurgical transsphenoidal surgery for pituitary tumors has been standard therapy for decades and was established by Harvey Cushing in the early twentieth century. Today, endoscopy is increasingly accepted in the therapy of pituitary lesions. In this retrospective study, we analysed the surgical technique and outcome of 50 patients with pituitary lesions treated with an endoscopic endonasal trans-sphenoidal approach. Methods Between January 2004 and July 2005, 50 patients (30 female and 20 male) with pituitary tumors were operated upon using an endoscopic endonasal trans-sphenoidal procedure without nasal speculum or postoperative nasal packing. The follow-up period ra…

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