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A Perneczky

Publications and source records attributed to A Perneczky.

At least 37 records · Page 2Linked to original sources
PubMed1998

Virtual endoscopy (VE) of the basal cisterns: its value in planning the neurosurgical approach.

Virtual endoscopy (VE) is a postprocessing technique based on a diverging ray casting algorithm to create perspective 3 D-images from computed tomographic angiography (CTA) and high resolution magnetic resonance imaging (MR) data. By applying VE to aneurysms, tumors, and vascular compression syndromes within the basal cisterns, endoscopic-like views of these structures are achieved from an intracisternal point above the cranial base. These views closely simulate the surgeon's impression during intraoperative endoscopy or microscopy and facilitate preoperative planning of different approaches.

Adult↗
PubMed1998

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 they provide rather narrow viewing angles. Thus, objects located directly opposite the approach entrance are more visible than those in the shadow of the microscope beam. These two deficiencies of keyhole craniotomies can be compensated for by the intraoperative use of rigid rod lens endoscopes, the shaft of which remains easily controllable through the surgical microscope. CONCEPT: Endoscope-assisted microsurgery, like all routine microsurgical procedures, is performed with both hands; the endoscope is fixed in its desired position via a mechanical arm to the headholder. Because of their superior optical quality and maneuverability, only rigid lens scopes are used for endoscope-assisted brain microsurgery. There are five ways of observing the endoscopic and microscopic images at the same time: 1) observation of the microscopic image through the oculars of the microscope and observation of the endoscopic image on a video screen placed in front of the surgeon, 2) observation of the microscopic image through the oculars of the microscope and display of the endoscopic image on a head-mounted LCD screen, 3) projection of both microscopic and endoscopic images on one screen in a picture-in-picture mode, 4) projection of both microscopic and endoscopic images into specially designed microscope oculars, and 5) transmission of both microscopic and endoscopic images into a head-mounted LCD screen. DISCUSSION: With the knowledge of almost all individual anatomic and pathoanatomic details of a specific patient, it is possible to target the individual lesion through a keyhole approach using the particular anatomic windows. As the light intensity and the depiction of important anatomic details are improved by the intraoperative use of lens scopes, endoscope-assisted microsurgery during keyhole approaches may provide maximum efficiency to remove the lesion, maximum safety for the patient, and minimum invasiveness.

Brain↗
PubMed1998

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 give an impression of possible indications for endoscope-assisted microsurgical procedures, and, with illustrative cases, to delineate the advantages of endoscopes used as surgical instruments during microsurgical approaches to intracranial lesions. METHODS: During a period of 4.5 years, 380 microsurgical procedures were performed as endoscope-assisted microneurosurgical operations. This surgical series was analyzed for time of surgery, usefulness of intraoperative endoscopy, and complication rates. Lens scopes with viewing angles of 0 to 110 degrees and with diameters of 2.0 to 5.0 mm as well as newly designed "viewing dissectors" (curved, rigid fiberscopes) with diameters of 1.0 to 1.5 mm connected to a video unit were used as microsurgical instruments. The positioning of the endoscopes was achieved by retractor arms fixed to the Mayfield headholder. Thus, the surgeon was able to perform customary microsurgical manipulations with both hands under simultaneous endoscopic and microscopic control. RESULTS: The lesions treated with endoscope-assisted microsurgery comprised 205 tumors, 53 aneurysms, 86 cysts, and 36 neurovascular compression syndromes. Eighty-nine of these lesions were localized in the ventricular system, 242 in the subarachnoid space or intracerebral, and 49 in the sella. Endoscope-assisted microsurgery was advantageous to reduce the size and the operation-related tissue trauma of approaches to lesions within the ventricular system, in the brain tissue as well as in the subarachnoid space at the base of the brain. Using less retraction during tumor removal, the visual control of retrosellar, endosellar, retroclival, and infratentorial structures was improved. Video-endoscope instrumentation was especially helpful during procedures in the posterior cranial fossa and at the craniocervical junction. It allowed for inspection of channels and hidden structures (e.g., the internal auditory meatus, the ventral surface of the brain stem, the ventral aspect of root entry zones of cranial nerves, the content of the foramen magnum, and the upper cervical canal), both without retraction and without resection of dura and bone edges. Endoscope instrumentation during surgery for large or giant aneurysms was useful to dissect perforators on the back side of the aneurysms and to control the completeness of clipping. CONCLUSION: Although the results reported herein cannot be compared directly with those of exclusive microsurgical procedures performed during the same period of time, videoendoscope-assisted microsurgery can be recommended as a time-saving, trauma-reducing procedure apt to improve postoperative outcomes.

Adolescent↗
PubMed1998

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 be treated adequately, resulting in a low morbidity rate, using neuroendoscopy or endoscope-assisted microsurgery. This specific surgical technique is presented.

Adult↗
PubMed1998

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). The follow-up period ranged from 6 to 44 months (mean follow-up duration, 14 mo). The indications were hydrocephalus in 17 patients, focal neurological deficits in 4 patients, progressive nonlocalizing symptomatology in 13 patients, and space occupation in 2 asymptomatic patients. EN was used in 14 cases, EAM in 15 cases, and ECM in 7 cases. RESULTS: The overall success rate was 70%. Nine patients (25%) had unchanged symptomatology, and the condition of two patients (5%) deteriorated. The best success rates were achieved in patients with intraventricular cysts (89%) and posterior fossa ACs (78%). Symptomatic improvement was best achieved in patients with hydrocephalus or focal neurological deficits (81%). CONCLUSION: Different endoscopic techniques (i.e., EN, EAM, and ECM) provide sufficient treatment of selected intracranial cysts. Our data suggest that intraventricular cysts and suprasellar ACs should be approached using EN whereas posterior fossa and sylvian ACs may be more effectively treated using a combined technique (EAM or ECM).

Adolescent↗
PubMed1998

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 control. Even the clipping procedure was performed in seven cases exclusively under endoscopical observation. Only one prematural rupture occurred intraoperatively during preparation of a basilar tip aneurysm. Postoperatively three individuals with aneurysms located in the posterior circulation were temporarily neurologically impaired, and one patient with a basilar tip aneurysm suffered from a surgical related hemiparesis. The use of an endoscope in aneurysm surgery improves the visualization of the aneurysm itself and the surrounding anatomical structures. This minimizes the retraction of the nervous structures and leads to a reduced morbidity.

Endoscopy↗
PubMed1997

[Hyperthyroidism in TSH-producing hypophyseal adenoma].

HISTORY AND CLINICAL FINDINGS: For 5 years a 59-year-old man had been treated with thyrostatic drugs for hyperthyroidism of unknown aetiology. As he had been losing weight, computed tomography had been performed in the search for a malignancy. It revealed a hypophyseal space-occupying lesion. INVESTIGATIONS: Peripheral thyroid hormone activities were raised, while thyroid-stimulating hormone (TSH) was also raised to 12.4 mU/l and there was evidence of partial hypophyseal insufficiency. Octreotide scintigraphy demonstrated increased activity in the area of the hypophysis. TREATMENT AND COURSE: The transsphenoidal surgery and immunohistochemical tests confirmed the diagnosis of TSH-producing hypophyseal adenoma. The patient became euthyroid after the operation. CONCLUSION: TSH-producing hypophyseal adenoma should be considered as a rare cause of hyperthyroidism when it is combined with non-suppressed TSH.

Adenoma↗
PubMed1997

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 OGTT < 2 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 GH < 5 ng/ml, 64% had a GH in the OGTT < 2 ng/ml and 73% had normalization of IGF-1. The combined criteria of OGTT < 2 ng/ml and IGF-1 normalization have been fulfilled in 59% of patients. None of these latter patients developed a clinical recurrence during the follow-up period. An optimal result (endocrinological cure, no permanent surgical complications and intact pituitary function) was achieved in 43% of patients. Although surgery was responsible for 19 new pituitary axis deficiencies (7 corticotropic axis, 8 thyrotropic axis and gonadotropic axis), 22 partial deficiencies improved to normalization after surgery (respectively 6, 3, and 13). Pre-operatively 55% of patients had no pituitary deficiency, after surgery this was 61%, leaving a net positive result of 6% less pituitary deficiencies. The authors conclude that normalization of IGF-1 combined with an OGTT < 2 ng/ml are adequate criteria for the definition of cure of acromegaly. However, the authors propose to include post-treatment hypopituitarism as an additional criterion by which treatment of acromegaly should be evaluated.

Acromegaly↗
PubMed1997

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 exposure of carotid-ophthalmic aneurysms. METHODS: In a series of 51 patients with 58 aneurysms of the ophthalmic segment of the internal carotid artery, nine patients with 10 aneurysms (4 large aneurysms, 6 small aneurysms) were treated via a contralateral microsurgical approach after careful preoperative planning. Preoperative planning was based on the analysis of clinical and radiographic data, including cranial computed tomography, magnetic resonance imaging, magnetic resonance angiography, and conventional cerebral angiography. RESULTS: The postoperative results were good in 38 (75%) of the patients, fair in 2 (4%), and poor in 3 (6%); 8 (15%) of the patients died after surgery. The postoperative follow-up was 4 months to 10 years. Postoperatively, 15 of 19 patients with uni- or bilateral visual deficits or visual field defects improved, 3 of the 19 patients experienced postoperative impairment of visual function, and 1 of the 19 patients had an unchanged visual field deficit. Visual impairment or unchanged visual function was observed in patients who underwent ipsilateral approaches, which was possibly caused by inappropriate intraoperative retraction of the optic nerve or chiasm. In all patients presenting with preoperative visual deficits who were treated via contralateral approaches, visual function improved in the postoperative course. CONCLUSION: Giant carotid-ophthalmic aneurysms that are eligible for surgical treatment as well as small and large aneurysms dislocating the optic nerve or the chiasm superomedially or medially should be approached via ipsilateral craniotomies. It is recommended that small and large aneurysms of the carotid-ophthalmic segment originating medially, superomedially, or superiorly, displacing the optic nerve or the chiasm superiorly, superolaterally, or laterally, be approached via contralateral craniotomies.

Adult↗
PubMed1997

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. The complications encountered included five cases of permanent cranial nerve palsy, two cases of cerebrospinal leakage, two cases of short memory disturbance, two cases of seizure, and one case each of hemiplegia and incoordination, transient hearing loss and tinnitus, and consciousness deterioration and hemiplegia. CONCLUSION: With careful patient selection, the subtemporal keyhole approach diminishes tissue traumatization considerably and has proven to provide sufficient operating space in the suprasellar area. When this approach is combined with the cranial base technique, the petroclival region can also be treated. However, the subtemporal keyhole approach requires deliberate preoperative planning for each patient, as well as for each surgeon.

Adolescent↗
PubMed1997

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 requires 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 suspicious for EDH. A myelogram and a post-myelographic computed tomographic scan demonstrated the lesion and its extent craniocaudally. INTERVENTION: Emergency decompressive surgery and removal of the hematoma were performed via an anterior approach. Control for total removal of the EDH was achieved using a flexible neuroendoscope providing visualization of the anterior epidural space from the foramen magnum to the T1 level. Surgery was accomplished by vertebral body replacement and anterior plating. CONCLUSION: Spinal endoscopy seems to be a useful tool in the surgical treatment of spinal EDH, providing control of the adjacent levels and allowing the limitation of the extent of bony resection.

Aged↗
PubMed1997

Frame-based and frameless endoscopic procedures in the third ventricle.

Stereotactic guidance is useful for planning an accurate trajectory to the third ventricle. A guiding block with a ball joint was developed for frame-based endoscopy and adaptors for arm-based and armless navigation systems. Between 1992 and 1996, 52 patients were operated on endoscopically in the third ventricle under stereotactic guidance. Thirty-eight ventriculostomies, 13 biopsies and 10 cystic lesions were performed. The coordinates of two points were calculated; one in the foramen of Monro and the second in the third ventricle. The ventriculostomy was performed under endoscopic control bluntly with a Fogarty catheter in front of the basilar artery. Twenty-seven (71%) of the patients had a long-lasting benefit from the operation, 6 (16%) had no benefit, and in 5 (13%) a shunt operation was necessary. Poor outcome was due to closure of the stoma by tumor growth or infection. Three cysts were fenestrated and 7 colloid cysts partly evacuated. One incident of bleeding occurred in the frontal lobe in the path of the endoscope which was treated conservatively with success. Transient memory deficit was noted in one patient and double vision in the second.

Adolescent↗
PubMed1997

[Surgical strategy in cases of multiple aneurysms].

Over a 4 year period 50 patients (34 women, 16 men; median age 48.5 years, range 24-69 ys.) were operated on multiple intracranial aneurysms (MA) and 283 patients (178 women, 105 men, median age 50.0 years; range 22-82 ys.) on single aneurysms (SA). A subarachnoid hemorrhage (SAH) occurred in the MA-group (in total 123 aneurysms, 5 giant aneurysms) in 43 cases, in the SA-group in 257 cases. Fifty-seven percent of all patients were operated on within 48 hours after SAH, 14% between day 3 and 7, 29% after day 7. There were no significant differences in the Hunt & Hess grading or in the distribution of ruptured aneurysms between both groups. Operation time was longer by 70 min in MA-patients than in SA-patients, but did not significantly influence the outcome in that group (rs = 0.200; p = 0.163). In 74% of the patients all aneurysms could be eliminated in one stage, among them 18 had bilateral or supra-infratentorial aneurysms. The step by step occlusion of the aneurysms was performed by dissecting all aneurysms and by clipping the deepest one and the bleeding source first. In 8 cases, all aneurysms were clipped through a contralateral keyhole approach.--After a mean follow up period of 1 year, 72% of the MA-patients and 65% of the SA-patients had made an excellent or good recovery. The morbidity rate was 22% in the MA- and 30% in the SA-patients. The operative mortality amounted to 6% in the MA- and 5% in the SA-group. The differences in outcome of both groups were not significant. Considering a bleeding risk of 1-2% per year, we suggest the operative treatment of all identified aneurysms, if possible in a one-stage, if necessary in a two-stage procedure in an individually tailored approach.

Adult↗
PubMed1996

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 reflected not only the preoperative cranial nerve deficit but also the feasibility of surgical resection. Cranial nerve function deteriorated after operations in 14% of oculomotor nerves, in one abducent nerve, in 58% of trochlear nerves, and in 21% of trigeminal nerves. We encountered improvement of function in 43% of oculomotor nerves, in 50% of abducent nerves, and in approximately 30% of the second and third but in only 7% of the first branches of trigeminal nerves. There was no improvement in trochlear nerve function. Improvement of oculomotor nerve function was observed only in moderately impaired nerves, which indicates that surgery should be undertaken early to preserve or improve oculomotor nerve function.

Cavernous Sinus↗
PubMed1996

Teleconsultation: a new neurosurgical image transfer system for daily routine and emergency cases--a four-year study.

In January 1991, an image transfer unit was developed and installed in the neurosurgical department of the University in Mainz. The system provides an image transfer of patient data via fibreoptic cable networks (VBN), ISDN, and public telephone line. In the following 4 years, 432 consultations were recorded. Nine departments were linked within this system. They provided an emergency out-patient department for primary treatment and radiology. The lack of a neurosurgical department in these clinics was made up for by the image transfer system. In these rural medical departments, teleconsultation improves the care of daily routine neurosurgical cases, as well as in emergency cases. There is also a decrease of costs due to teleconsultation. The image transfer via simple public telephone line was sufficient.

Adolescent↗
PubMed1996

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 cultured peripheral blood monocytes from 14 patients with malignant gliomas were compared to those from 12 controls (seven with nontumorous disease and five healthy individuals). Using an enzyme-linked immunosorbent assay for EGF, the EGF content of cell culture supernatants was determined at Days 7, 21, and 100 of culture. The EGF content (mean +/- standard error) of supernatants was 5.9 +/- 0.2 pg/ml/10(3) glioma monocytes versus 1.3 +/- 0.1 pg/ml/10(3) control monocytes at Day 7 of culture, 22.9 +/- 0.8 pg/ml/10(3) glioma monocytes versus 1.8 +/- 0.9 pg/ml/10(3) control monocytes at Day 21 of culture, and 23.4 +/- 0.7 pg/ml/10(3) glioma monocytes, and below detection levels for control monocytes at Day 100 of culture. Steroid treatment of glioma patients did not influence the EGF release of cultured monocytes. These data indicate that glioblastoma-associated peripheral blood monocytes may be distinct from those of healthy individuals. Moreover, this study indicates that subtypes of glioma-associated peripheral blood monocytes may support immunosuppression and promote growth of malignant glioma by releasing unusually high amounts of EGF.

Brain Neoplasms↗
PubMed1995

Unspecific metabolic blood parameters as used in clinical routine may differentiate malignant from benign cerebral tumors.

The investigation of rather insensitive metabolic parameters (protein, fibrinogen, blood urea nitrogen (BUN), blood glucose) reveals significant differences between tumor-bearing and tumor-free patients as well as benign and malignant neoplasms. Whereas metastases and glioblastomas (GBM) show significantly elevated BUN levels (21.9 +/- 1.7; 8 +/- 2.2 mg/dl) compared to benign tumors (meningioma WHO I, astrocytoma I, II) (16 +/- 0.9 mg/dl) and tumor-free matched controls (e.g. 13.9 +/- 1.4 mg/dl) only metastases depict higher glucose (141.7 +/- 11mg/dl) counts. Fibrinogen, significantly elevated in malignancy (395 +/- 25.2; 397.2 +/- 25.9 mg/dl) is without difference between meningioma, astrocytoma (253.2 +/- 16.6; 271.5 +/- 16.5 mg/dl) and controls (e.g. 270.1 +/- 10.8 mg/dl). Correlating BUN with total protein reveals a metabolic mismatch to nearly all tumor patients, regardless of dignity, as compared to tumor-free patients. Neuroendocrinoimmunological changes are the most likely reason for these overt as well as occult findings, making investigation of more sensitive metabolic parameters a rewarding task.

Adult↗