Normal position of the aqueduct of Sylvius

1975 ◽  
Vol 42 (5) ◽  
pp. 503-507 ◽  
Author(s):  
Karl Guldberg Krogness
Keyword(s):  
Standard Deviation ◽  
Cerebral Aqueduct ◽  
Posterior Surface ◽  
Normal Position ◽  
Normal Value ◽  
Content Type ◽  
Abnormal Position ◽  
Tuberculum Sellae ◽  
Fine Print

✓ Two new proportional methods for determination of the normal or abnormal position of the cerebral aqueduct are described. The position of the iter is expressed by the quotients and , when d-aq represents the distance between the upper posterior surface of the dorsum sellae and the dorsal center of the air-filled aqueduct. Ts = aq is the distance from the tuberculum sellae to the same point, and Tw is Twining's line. The normal value of the dorsum to aqueduct ratio was 0.32 ± 0.02 standard deviation (SD) and of the tuberculum to aqueduct ratio 0.44 ± 0.03 SD. Both proportional methods are independent of skull dimensions. These are compared to another proportional method described in Part 1 of this report.

Posterior petrous meningiomas: 82 cases

2005 ◽  
Vol 102 (2) ◽  
pp. 284-289 ◽  
Author(s):  
Zhe Bao Wu ◽  
Chun Jiang Yu ◽  
Shu Sen Guan
Keyword(s):  
Facial Nerve ◽  
Clinical Manifestations ◽  
Petrous Bone ◽  
Type I ◽  
Type Ii ◽  
Posterior Surface ◽  
Total Resection ◽  
Content Type ◽  
Functional Preservation ◽  
Fine Print

Object. The aim of this study was to discuss posterior petrous meningiomas—their classification, clinical manifestations, surgical treatments, and patient outcomes. Methods. A retrospective analysis was performed in 82 patients with posterior petrous meningiomas for microsurgery. According to the anatomical relationship with the posterior surface of the petrous bone and with special reference to the internal auditory canal (IAC), posterior petrous meningiomas were classified into three types: Type I, located laterally to the IAC (28 cases); Type II, located medially to the IAC, which might extend to the cavernous sinus and clivus (32 cases); and Type III, extensively attached to the posterior surface of the petrous bone, which might envelop the seventh and eighth cranial nerves (22 cases). Sixty-eight (83%) of 82 cases involved total resection. The rate of anatomical preservation of facial nerve was 97.5%, whereas the functional preservation rate was 81%. The rate of hearing preservation was 67%. All Type I tumors were completely resected, and the rate of anatomical preservation of facial nerve was 100% and functional preservation was 93%. Regarding Type II lesions, 75% of 32 cases involved total resection; the rate of anatomical preservation of facial nerve was 97% and functional preservation was 75%. For Type III lesions, 73% of 22 cases were totally resected. The rate of anatomical preservation of facial nerve in patients with this tumor type was 95%, whereas functional preservation was 73%. Conclusions. Clinical manifestations and surgical prognoses are different among the various types of posterior petrous meningiomas. It is more difficult for Types II and III tumors to be resected radically than Type I lesions, and postoperative functional outcomes are significantly worse accordingly. The primary principles in dealing with this disease entity include preservation of vital vascular and central nervous system structures and total resection of the tumor as much as possible.

A method of estimating intracranial decompensation in man

1976 ◽  
Vol 45 (2) ◽  
pp. 155-158 ◽  
Author(s):  
Jerzy Szewczykowski ◽  
Pawel Dytko ◽  
Adam Kunicki ◽  
Jolanta Korsak-Sliwka ◽  
Stanislaw Sliwka ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Intracranial Pressure ◽  
Characteristic Feature ◽  
Computer System ◽  
Monitoring System ◽  
New Method ◽  
Icp Monitoring ◽  
Content Type ◽  
On Line ◽  
Fine Print

✓ A new method of estimating intracranial decompensation in man is described. An on-line computer system is connected to an intracranial pressure (ICP) monitoring system to compute regression plots of mean ICP vs standard deviation; standard deviation is used as a measure of ICP instability. Two zones with distinctly different slopes are a characteristic feature of these plots. It is thought that the changes of slope signify intracranial decompensation.

Families, brain death, and traditional medical excellence

1984 ◽  
Vol 60 (6) ◽  
pp. 1192-1194 ◽  
Author(s):  
Rosa Lynn Pinkus
Keyword(s):  
Brain Death ◽  
Tertiary Care Hospital ◽  
Tertiary Care ◽  
Care Hospital ◽  
Personal Beliefs ◽  
Content Type ◽  
The Past ◽  
Transplant Center ◽  
Fine Print

✓ Staff neurosurgeons and residents at a tertiary care hospital designated as a transplant center were surveyed regarding personal opinions concerning brain death and family conferences. Compared to an extensive survey done in 1976, the responses indicated that, while a professional consensus regarding the definition and meaning of brain death has emerged in the past 10 years, a range of personal beliefs and opinions regarding the concept still exists. In spite of the professional consensus, it is still difficult for the physician to communicate gently, yet firmly, to families both the scientific groundwork that validates the determination of brain death, the concept, and the finality of the information.

Surgical anatomy of the juxta—dural ring area

1998 ◽  
Vol 89 (2) ◽  
pp. 250-254 ◽  
Author(s):  
Susumu Oikawa ◽  
Kazuhiko Kyoshima ◽  
Shigeaki Kobayashi
Keyword(s):  
Surgical Anatomy ◽  
Lateral View ◽  
Horizontal Line ◽  
Anterior Clinoid Process ◽  
Lateral Projection ◽  
Content Type ◽  
Medial Side ◽  
Tuberculum Sellae ◽  
Planum Sphenoidale ◽  
Fine Print

Object. The authors report on the surgical anatomy of the juxta—dural ring area of the internal carotid artery to add to the information available about this important structure. Methods. Twenty sides of cadaver specimens were used in this study. The plane of the dural ring was found to incline in the posteromedial direction. Medial inclination was measured at 21.8° on average against the horizontal line in the anteroposterior view on radiographic studies. Posterior inclination was measured at 20.3° against the planum sphenoidale in the lateral projection, and the medial edge of the dural ring was located 0.4 mm above the tuberculum sellae in the same projection. The lateral edge of the dural ring was located 1.4 mm below the superior border of the anterior clinoid process. The carotid cave was situated at the medial or posteromedial aspect of the dural ring; however, two of the 20 specimens showed no cave formation. The carotid cave contained the subarachnoid space in 13 sides, the arachnoid membrane only in three sides, and the extraarachnoid space in two sides. The authors propose that the marker of the medial side of the dural ring, which is more proximal than the lateral, is the tuberculum sellae in the lateral view on radiographic studies. In the medial aspect of the dural ring the intradural space can be situated below the level of the tuberculum sellae because of the existence of the carotid cave. Conclusions. An aneurysm arising from the medial side of the juxta—dural ring area even below the tuberculum sellae is a potential cause of subarachnoid hemorrhage.

Beagle puppy model of intraventricular hemorrhage

1983 ◽  
Vol 58 (6) ◽  
pp. 857-862 ◽  
Author(s):  
Laura R. Ment ◽  
William B. Stewart ◽  
Charles C. Duncan ◽  
David T. Scott ◽  
Richard Lambrecht
Keyword(s):  
Intraventricular Hemorrhage ◽  
The Other ◽  
Prostaglandin Synthetase ◽  
Content Type ◽  
Hemorrhagic Hypotension ◽  
Carbon 14 ◽  
Blood Pressure Responses ◽  
To Receive ◽  
Fine Print

✓ The newborn beagle puppy has been demonstrated to provide a good model for neonatal intraventricular hemorrhage (IVH). A study was designed to determine if indomethacin can prevent IVH and if indomethacin would produce changes in cerebral blood flow (CBF). Newborn beagle puppies were randomized by computer into two groups: one was pretreated with indomethacin, a known inhibitor of prostaglandin synthetase, and the other was saline. The dogs in both groups were then assigned either to undergo hemorrhagic hypotension/volume reexpansion insult or to receive no insult. Twenty percent of all pups receiving indomethacin and undergoing the insult experienced IVH, compared to 71% of the pups undergoing insult that had been pretreated with saline. Significant alterations in the blood pressure responses to the hemorrhagic hypotension/volume reexpansion insult were noted in the former group compared to the saline-pretreated pups subjected to insult. Finally, employing carbon-14 autoradiography for the determination of CBF, it was demonstrated that indomethacin decreases resting CBF of the newborn beagle pups and, in indomethacin-pretreated animals subjected to insult, prevents the increases in CBF seen in the saline-pretreated traumatized pups.

A method for monitoring antifibrinolytic therapy in patients with ruptured intracranial aneurysms

1981 ◽  
Vol 54 (1) ◽  
pp. 12-15 ◽  
Author(s):  
Kim J. Burchiel ◽  
Gottfried Schmer
Keyword(s):  
Fibrinolytic Activity ◽  
Intracranial Aneurysms ◽  
Aminocaproic Acid ◽  
Content Type ◽  
Antifibrinolytic Therapy ◽  
Epsilon Aminocaproic Acid ◽  
Ruptured Intracranial Aneurysms ◽  
Control Plasma ◽  
Fine Print

✓ A rapid fluorometric assay technique has been utilized to assess the degree of fibrinolytic inhibition in 20 patients with ruptured intracranial aneurysms treated with epsilon-aminocaproic acid (EACA). This method quantitates the available plasminogen activity (APA) of plasma, and has proven to be a reliable means of monitoring antifibrinolytic therapy. Determination of the plasma APA also permits correlation of the level of fibrinolytic activity with putative complications of EACA therapy. Normal control plasma APA was 3.1 ± 0.7 CTA units/ml, but in patients with subarachnoid hemorrhage (SAH), pretreatment fibrinolytic activity was supranormal at 3.78 ± 0.88 CTA units/ml. During continuous intravenous administration of EACA (1.5 gm/hr) in patients with SAH, the plasma fibrinolytic activity was decreased to 0.9 ± 0.31 CTA units/ml. A case is described which exemplifies the use of this assay. In addition, an approach to monitoring antifibrinolytic therapy using the plasma APA is proposed.

Neurosurgical applications of ocular pneumoplethysmography

1981 ◽  
Vol 54 (5) ◽  
pp. 588-595 ◽  
Author(s):  
William F. Bingham
Keyword(s):  
Standard Deviation ◽  
Carotid Artery ◽  
Intracranial Aneurysm ◽  
Carotid Endarterectomy ◽  
Contralateral Side ◽  
Artery Occlusion ◽  
Carotid Artery Occlusion ◽  
Content Type ◽  
Final Adjustment ◽  
Fine Print

✓ Ocular pneumoplethysmography (OPG), a semiautomated form of suction ophthalmodynamometry, was used to evaluate and follow 15 patients who underwent carotid endarterectomy and two patients in whom gradual carotid artery occlusion was performed for inoperable intracranial aneurysm. Postoperative corrected ophthalmic arterial pressures (COAP's) on the operated side in the carotid endarterectomy patients averaged 12.5 mm Hg higher than before surgery, the standard deviation being 4.9 mm Hg for clinically stable patients. There was no significant change in COAP on the contralateral side. Several problems were encountered in closing down carotid clamps, the most potentially serious being a precipitous fall in COAP with the final adjustment. The current uses of OPG and similar techniques are reviewed, and potential neurosurgical applications are discussed.

Percutaneous restoration of a kinked shunt

1979 ◽  
Vol 50 (3) ◽  
pp. 391-392 ◽  
Author(s):  
Stephen E. Natelson
Keyword(s):  
Normal Position ◽  
Wire Loop ◽  
Content Type ◽  
Atrial Catheter ◽  
Thin Walled ◽  
Fine Print

✓ A thin-walled atrial catheter used in shunting for hydrocephalus may become curled or kinked in the neck after it has been in normal position and functioning for years. The usual cause is a bout of severe coughing. Such a case is described together with a percutaneous method of restoration of the shunt by transfemoral catheterization utilizing a wire loop.

New method for intraoperative determination of proper screw insertion or screw malposition

2000 ◽  
Vol 93 (1) ◽  
pp. 40-44 ◽  
Author(s):  
Sabri Cem Açıkbaş ◽  
Mehmet Recai Tuncer
Keyword(s):  
Imaging Techniques ◽  
New Method ◽  
Lumbar Region ◽  
Content Type ◽  
Screw Insertion ◽  
Transpedicular Instrumentation ◽  
Thoracolumbar Injury ◽  
Major Vessel ◽  
Fine Print

Object. Inadequate imaging techniques may lead to misjudgment of screw positioning when applying transpedicular instrumentation; this can create potential risks of major vessel and nerve damage. In this article the authors present a new method to determine screw malpositioning intraoperatively. Methods. The authors retrospectively evaluated pre- and postoperative plain radiographs of 97 spinal segments in which screws had been placed in 41 patients suffering from thoracolumbar injury who had previously undergone transpedicular screw fixation. They developed a new mathematical equation with which they determine the distance ratios of two screw tips in the same segment by comparing the distance between the pedicles on preoperative radiographs with those on postoperative radiographs. Subsequently, the results are compared with postoperative computerized tomography findings to determine which screws are in the correct position and which are penetrating the medial or lateral cortex of the pedicle. It was found that the ratio range of correctly placed screw tips was 46 ± 10% (mean ± standard deviation) in the thoracic region and 60 ± 9% in the lumbar region (ranges 43–50% and 57–63%, respectively, 95% confidence intervals). Higher ratios (higher percentages) than these values indicated extreme closeness of screw tips and therefore medial malpositioning. Lower ratios (lower percentages) indicated lateral malpositioning. Conclusions. This proposed method may provide intraoperative determination of correct screw positioning or malpositioning. This method allows surgeons to replace the malpositioned screw, and, consequently, early resolution of neurovascular injuries is made possible. Additionally, repositioning of the screw correctly will avoid rigidity failure of the fixation device.

Nasal encephaloceles: definitive one-stage reconstruction

1988 ◽  
Vol 68 (4) ◽  
pp. 571-575 ◽  
Author(s):  
Larry A. Sargent ◽  
Alan E. Seyfer ◽  
E. Neal Gunby
Keyword(s):  
Lateral Displacement ◽  
Bone Grafts ◽  
Early Age ◽  
Normal Position ◽  
Facial Skeleton ◽  
Skeletal Deformity ◽  
Content Type ◽  
Facial Contour ◽  
One Stage Reconstruction ◽  
Fine Print

✓ Nasal encephaloceles can cause complex deformities of the naso-orbital skeleton. As the encephalocele pushes through a defect in the facial skeleton it causes lateral displacement of the medial orbital walls. Correction of this skeletal deformity is necessary to achieve a normal facial contour. Two examples of nasal encephaloceles are presented and the classification, diagnosis, and treatment of this entity are discussed. The correction of these deformities at an early age is recommended. The suggested method of reconstruction is a combined intracranial and extracranial approach with mobilization of the nasal skeleton and medial orbital walls to their normal position. The remaining defects are treated with bone grafts.

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