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M Dujovny

Publications and source records attributed to M Dujovny.

At least 73 records · Page 4Linked to original sources
PubMed1996

Evaluation of outcome after intracranial aneurysm surgery: the neuropsychiatric approach.

BACKGROUND: With the reduction of mortality and gross neurologic morbidity of patients undergoing intracranial aneurysm surgery, the interest in outcome is shifting towards more subtle aspects such as cognitive deficits and psychosocial adjustment. METHODS: We discuss two different ways of measuring outcome in a sample of 20 patients who had intracranial aneurysm surgery. Patients were evaluated at discharge using the Karnofsky Scale and the Glasgow Outcome Scale. Six months after discharge we conducted a neuropsychiatric evaluation including cognitive, behavioral, and mood status assessment. RESULTS: Although 13 of out patients had a "good recovery, " 18 had some neuropsychiatric impairment. Comparing patients with "good recovery" with the remainder, patients with poorer outcomes tended to have a left pterional approach, a poorer "drive", and language disorders (p < 0.05). There was no correlation between out cognitive, mood, and behavioral assessment and the results of the Karnofsky and Glasgow Outcome Scales ( p > 0.05). CONCLUSIONS: we conclude that neuropsychiatric deficits are common after intracranial aneurysm surgery and that for our study the Karnofsky Scale and Glasgow Outcome Scale were not sensitive enough to detect residual impairment. therefore, it is important to develop brief tests and scales able to identify these problems and to complement the standard clinical neurological examination.

Adult↗
PubMed1996

Microanatomical basis for the third ventriculostomy.

In the last few years, there has been a resurgence of interest in endoscopic third ventriculostomy as a treatment for obstructive hydrocephalus. Although various techniques have been used to perform this procedure, not enough emphasis has been placed on the microanatomical details of the third ventricle and surrounding cisterns in relation to this procedure. Using a surgical microscope we examined the microsurgical anatomy of the floor of the third ventricle floor and related subarachnoid cisterns in 20 adult brains using the "immersion technique" in conjunction with microsurgical dissection. We believe that the optimal place to fenestrate is the midline of the floor of the third ventricle, behind the infundibular recess and in front of the mammillary bodies, communicating the third ventricle with the anterior interpeduncular cistern, minimizing the risk for vascular lesions. Stereotactic third ventriculostomy is a safe and effective way of re-establishing normal cerebrospinal fluid flow dynamics in selected cases of obstructive hydrocephalus. However, in an endoscopic exposure only a small portion of the anatomy can be seen at any one time, and important neurovascular structures may be located adjacent to the endoscope, but outside of the visual range of the lens. A thorough understanding of the microanatomy of the neural and vascular structures surrounding the third ventricle and related cisterns is essential in order to improve surgical results avoiding complications.

Adult↗
PubMed1996

Microsurgical anatomy of the infratentorial trabecular membranes and subarachnoid cisterns.

The understanding of the anatomy of the subarachnoid cisterns and trabecular membranes is of paramount importance in the surgical treatment of pathology of the posterior fossa. Aneurysms, arteriovenous malformations, and some tumors should be approached through the subarachnoid space. The subarachnoid cisterns provide natural pathways to approach neurovascular and cranial nerve structures. The microsurgical anatomy of the infratentorial subarachnoid cisterns was studied in twenty adult brains, using the 'immersion technique'. Air was injected into the subarachnoid cisterns and brains were dissected under the operative microscope. Six main compartmental trabecular membranes were identified in the infratentorial level. They divide the subarachnoid space into six cisterns. Cisternal divisions and the disposition of the trabecular membranes were closely related to the vascular divisional patterns of the principal arteries. Thorough knowledge of the microsurgical anatomy of the subarachnoid space will aid neurosurgeons during the surgical approach of many vascular and tumoral lesions located in the posterior fossa.

Adult↗
PubMed1996

Do we evaluate outcome appropriately?

We discuss two different ways of measuring outcome in a sample of 20 patients who had intracranial aneurysm surgery. Patients were evaluated at discharge using the Karnofsky Scale and the Glasgow Outcome Scale. Six months after discharge we conducted a neuropsychiatric evaluation including cognitive, behavioral, and mood status assessment. Although 13 of our patients had a "good recovery', 18 had some neuropsychiatric impairment. We did not find statistical relationships between the discharge evaluation and the neuropsychiatric assessment at follow-up. We discuss the need for developing new outcome measures to pick-up neuropsychiatric deficits, beyond the traditional neurologic semiology.

Adult↗
PubMed1996

Microsurgical anatomy of the arachnoidal trabecular membranes and cisterns at the level of the tentorium.

A clear and thorough understanding of the neuroanatomical structures of the subarachnoid cisterns is important because they provide natural pathways to intracranial arteries, veins, and nerves during microvascular procedures without disturbing surrounding important brain structures. Using a surgical microscope, we examined the microsurgical anatomy of the trabecular membranes and subarachnoid cisterns in 20 adult cadaver brains. The brains were immersed in Ringer's solution and air was injected into the subarachnoid cisterns while the brains remained submerged in solution. We identified seven trabecular membranes that limit six cisterns. We specifically looked at the anatomical relationship between the trabecular membranes and cisterns and their corresponding vessels and cranial nerves. The cistern divisions and the dispositions of trabecular membranes were closely related to the vascular division patterns of the principal brain arteries.

Adolescent↗
PubMed1996

Magnetic field gradients in the MRI suite and their effects on aneurysm clips.

We studied magnetic field intensity in the magnetic resonance imaging suite at our hospital and its possible effect on several different types of aneurysm clips, including one Heifetz 17-7 PH, six Heifetz Elgiloy, one Mayfield, six Perneczky, fifteen Sugita, one Sundt-Kees Variangle, four Variangle-McFadden and fifteen Yasargil clips. We carefully observed the clips for any translational or rotational movements along the path from the door towards the magnetic resonance imaging gantry. The magnetic field strength was 0.04 kiloGauss at the entrance of the room, with an acute increase of magnetic strength at 310 cm away from the entrance to the room, 90 cm to the entrance of the gantry. The magnetic strength continued to increase at a rate of 1.0-1.5 kiloGauss for every 20 cm up to the entrance to the gantry. No movement was observed in any of the clips at the entrance to the suite except for the Heifetz 17-7 PH clip, which showed small movement in the longitudinal plane of the clip. At the entrance to the gantry, the Heifetz 17-7 PH, Sundt-Kees Variangle, and Mayfield clips were aligned on the walls of the test container perpendicular to the magnetic bore. The, Heifetz Elgiloy, Perneczky, Sugita, Variangle-McFadden, and Yasargil clips showed no movement throughout the path of the stretcher or near the gantry.

Aneurysm↗
PubMed1995

Comparison of static conformal field with multiple noncoplanar arc techniques for stereotactic radiosurgery or stereotactic radiotherapy.

PURPOSE: Compare the use of static conformal fields with the use of multiple noncoplanar arcs for stereotactic radiosurgery or stereotactic radiotherapy treatment of intracranial lesions. Evaluate the efficacy of these treatment techniques to deliver dose distributions comparable to those considered acceptable in current radiotherapy practice. METHODS AND MATERIALS: A previously treated radiosurgery case of a patient presenting with an irregularly shaped intracranial lesion was selected. Using a three-dimensional (3D) treatment-planning system, treatment plans using a single isocenter multiple noncoplanar arc technique and multiple noncoplanar conformal static fields were generated. Isodose distributions and dose volume histograms (DVHs) were computed for each treatment plan. We required that the 80% (of maximum dose) isodose surface enclose the target volume for all treatment plans. The prescription isodose was set equal to the minimum target isodose. The DVHs were analyzed to evaluate and compare the different treatment plans. RESULTS: The dose distribution in the target volume becomes more uniform as the number of conformal fields increases. The volume of normal tissue receiving low doses (> 10% of prescription isodose) increases as the number of static fields increases. The single isocenter multiple arc plan treats the greatest volume of normal tissue to low doses, approximately 1.6 times more volume than that treated by four static fields. The volume of normal tissue receiving high (> 90% of prescription isodose) and intermediate (> 50% of prescription isodose) doses decreases by 29 and 22%, respectively, as the number of static fields is increased from four to eight. Increasing the number of static fields to 12 only further reduces the high and intermediate dose volumes by 10 and 6%, respectively. The volume receiving the prescription dose is more than 3.5 times larger than the target volume for all treatment plans. CONCLUSIONS: Use of a multiple noncoplanar conformal static field treatment technique can significantly reduce the volume of normal tissue receiving high and intermediate doses compared with a single isocenter multiple arc treatment technique, while providing a more uniform dose in the target volume. Close conformation of the prescription isodose to the target volume is not possible using static uniform conformal fields for target shapes lacking an axis of rotational symmetry or plane of mirror symmetry.

Brain Neoplasms↗
PubMed1995

Transcranial cerebral oximetry and carotid cavernous fistula occlusion. Technical note.

Different methods have been used in the evaluation and monitoring of the cerebral oxygen supply during neuro-interventional therapies. Attenuation of near-infrared light by the chromophores oxyhemoglobin and deoxyhemoglobin have shown to be useful in the study of the cellular oxygen metabolism and oxygen delivery to the brain. Transcranial cerebral oximetry (TCCO) has the advantage of providing real-time information regarding regional brain oxygen saturation (rSO2) by using wavelengths in the near-infrared range. We present a patient with a carotid cavernous fistula who underwent balloon occlusion and concurrent continuous TCCO monitoring. TCCO was found to be a useful tool providing immediate rSO2 values during the angiographic and interventional procedures. Initial balloon occlusion of a carotid cavernous fistula resulted in partial occlusion of the internal carotid artery lumen causing an immediate decrease in rSO2 which correlated with angiographic findings. Subsequent reocclusion of the fistula produced a slower and smaller degree of decrease in rSO2 with clinical improvement in the patient. Changes in rSO2 were detected before any adverse clinical event was observed. TCCO was reliable, safe, sensitive, and provided a real-time assessment tool for the monitoring of brain oxygen supply in a patient undergoing a neuroendovascular procedure.

Adolescent↗
PubMed1995

Microsurgical anatomy of the atlantal part of the vertebral artery.

BACKGROUND: Microanatomy of the vertebral artery has been the subject of multiple studies. However, none of them has covered every aspect of microvascular anatomy of the atlantal part of the vertebral artery. MATERIALS AND METHODS: Microsurgical anatomy of the atlantal part of the vertebral artery was studied in 14 cadaveric specimens. The artery was dissected using the standard microsurgical technique under operative microscope magnification. The atlantal part of the vertebral artery was divided into five segments: the foraminal, sagittal, transverse, medial condylar, and dural. The length of each segment was measured, as was the diameter of the artery. The branches of this part of the artery were identified and the distance between the point of dural entry of the artery and the midline of the atlanto-occipital dura was measured. Distance between the mastoid tip and the artery and the distance between the mastoid tip and the tip of C1 transverse process were measured. RESULTS: Results of all measurements are summarized in tables and text. We discuss various anomalies, branches, and lesions of the vertebral artery and surgical approaches with new methods of managing diseases in this area.

Atlanto-Axial Joint↗
PubMed1995

Anatomy of the sympathetic pathways in the cavernous sinus.

We studied sympathetic fibres in the cavernous sinus in 40 unfixed specimens obtained from human cadavers. Sympathetic fibres in the cavernous sinus are understood to be grouped in a plexiform configuration surrounding the internal carotid artery and have a diffuse distribution among the sympathetic nerves. Our study, however, suggests that a more systematic arrangement of sympathetic pathways exists in the cavernous sinus. A detailed anatomical description of intracavernous sympathetic fibres contributes to academic anatomical knowledge and may have practical applications for 1. diagnostic interpretation of pathologic conditions involving the cavernous sinus, 2. recognition and orientation of anatomical structures during intracavernous surgical procedures, and 3. a deeper understanding of the sympathetic nerve supply to cerebral vasculature.

Carotid Artery, Internal↗
PubMed1995

Modified solution for filling MRI coordinate indicators for the ZD stereotactic frame.

Increased use of magnetic resonance imaging and magnetic resonance angiography in stereotactic planning highlight some technical problems in imaging. Visualization of markers during imaging are vital in stereotactic planning. In magnetic resonance imaging-guided stereotaxy, specially designed plates are used that contain water-based copper sulfate solutions as a marker. Replacement of copper sulfate solution is usually required after some time due to precipitation and leaking. The refilling procedure is quite cumbersome and can cause technical problems in imaging. In this study, we describe copper sulfate solution mixed with a water-soluble gel as a simple but useful alternative to water-based copper sulfate resolution to ease the refilling procedure and to overcome the air bubbles.

Copper↗
PubMed1995

Postoperative cognitive and single photon emission computed tomography assessment of patients with resection of perioperative high-risk arteriovenous malformations.

We studied the outcome of 10 patients who had undergone high-risk surgery for an arteriovenous malformation at our institution between November 1991 and November 1993. All of the lesions were located in the dominant (left) hemisphere. Perioperative risk was assessed by the location of the lesion in functionally eloquent cortex (seven patients) or deep structures (two patients) or the lesion's large volume (two patients). Our patients included six women and four men, and their ages ranged from 22 to 53 years (mean, 35.8). Our follow-up study included the evaluation of neurological sequelae but mainly emphasized the study of cognitive deficits (seven major functional clusters), the incidence of depression and behavioral changes, and the assessment of regional cerebral blood flow with single photon emission computed tomography. Six patients returned to a seemingly "normal" daily life with some minor deficits postoperatively, three developed contralateral hemiparesis, and one had disabling cognitive deficits. Our comprehensive cognitive assessment, in particular, showed that although patients might appear "normal" on a routine neurological examination, most patients showed a mild deficit in at least one cognitive function and three were severely impaired. In addition, the single photon emission computed tomographic studies pointed out hypoperfusion in more extensive regions than the surgical defects shown by magnetic resonance imaging or computed tomographic studies. These single photon emission computed tomography images helped to explain some of the cognitive and behavioral changes better than the anatomic studies. This information will make it possible for the physician to offer continuing supportive care for the patient in postoperative transition to normal life activities.

Adult↗
PubMed1995

Regional cerebral oxygen saturation during intra-arterial papaverine therapy for vasospasm: case report.

Cerebral arterial vasospasm continues to be a major secondary medical complication of aneurysmal subarachnoid hemorrhage. Despite hypervolemic hemodilution, arterial hypertension, and pharmacological therapy, morbidity and mortality due to vasospasm remain high. The authors discuss a patient with vasospasm who did not respond to traditional medical therapy and who underwent intra-arterial papaverine infusions while being monitored with transcranial cerebral oximetry. Oximetry during the procedure revealed significant improvements in brain regional saturation of oxygen, with the relief of vasospasm that correlated with clinical improvements in the patient's neurological status. Transcranial cerebral oximetry was used to monitor regional oxygen saturation throughout the angiographic and interventional procedures, providing continuous, real-time, clinically relevant information about the effects of vasospasm and its treatment.

Adult↗