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M C Preul

Publications and source records attributed to M C Preul.

At least 19 recordsLinked to original sources
PubMed2003

Effects of intravascular perfusion of cooled crystalloid solution on cold-induced brain injury using an extracorporeal cooling-filtration system.

BACKGROUND: We evaluated cerebral metabolic change during brain hypothermia with intravascular perfusion of cooled crystalloid solution using an extracorporeal cooling-filtration system and cerebroprotective effects of this hypothermia on brain injury in an animal model. METHOD: Microdialysis probes were implanted into the bilateral parietal cortices. A cold-induced brain injury was produced behind the microdialysis probe on the right parietal cortex. Immediately after injury in the cooled group (n=9), Ringer's solution cooled to 5 degrees C was infused into the right vertebral artery after occlusion of the bilateral common carotid and the left vertebral arteries. Excessive fluid was ultrafiltrated by a dialyzer. Brain temperature was maintained at about 20 degrees C for 60 minutes. In 7 dogs, three neck arteries were occluded for 60 minutes after injury without cooled fluid infusion. The extracellular concentrations of glutamate, lactate, and pyruvate were measured serially for 180 minutes after injury. FINDINGS: Extracellular glutamate concentrations in the cooled group did not increase, while there was a significant increase in the injured hemisphere as compared to the uninjured hemisphere in the non-cooled group ( P<0.05). Extracellular lactate concentrations increased slightly after occlusion in both groups. The depth of cortical injury was limited in the cooled group, but extended into the white matter in the non-cooled group up to 240 minutes after injury. INTERPRETATION: Occlusion of three main arteries induced ischaemia under critical threshold in canine brains. Under this condition, intravascular cooling with crystalloid solution suppressed accumulation of extracellular glutamate and reduced tissue damage in the early phase after cold-induced brain injury, as cerebroprotective effects. This information suggests that a method employing brain hypothermia via intra-arterial cooling with an extracorporeal cooling-filtration system has potential to achieve successful, safe, selective brain cooling.

Animals↗
PubMed2002

Endolymphatic sac tumor: unique features of two cases and review of the literature.

Endolymphatic sac tumors (EST) are rare intracranial tumors originating from the pars rugosa of the endolymphatic sac. Although typically described as histologically nonaggressive lesions, nevertheless they are termed adenocarcinomas and often become locally invasive. We report two patients with histologically proven EST with unique clinical features: the first pediatric case of an EST in an 11-year-old patient whose complaints started at the age of seven; and, a second patient, a 43-year-old man, the first report of metastatic EST which appeared in a remote location from the original site of surgery. Both patients underwent gamma-knife radiosurgery for recurrent tumor. This treatment has not been described previously for these tumors. Both patients have a follow-up of 7 years. Although not disease free they remain neurologically stable. We review the literature on EST.

Adenocarcinoma↗
PubMed2001

"The art is long and the life short": the letters of Wilder Penfield and Harvey Cushing.

Wilder Penfield and Harvey Cushing created legacies to neurosurgery, both in terms of those they trained and in their philosophical approach to the field. Their biographies provide only brief comments on their relationship without any thorough examination of their personal correspondence. In this article the Penfield-Cushing relationship is examined through an analysis of their unpublished personal letters. The Penfield-Cushing correspondence is a treasure for neurosurgery: it provides remarkable insight into the embryonic period of the discipline and into the relationship of two of the most influential figures in modern neurosurgery.

Correspondence as Topic↗
PubMed2001

Historical considerations of the diagnosis and treatment of facial pain.

Most forms of facial pain remain neurologic disorders that, although not life threatening, can be debilitating. Modern descriptions of the various forms of facial pain according to their clinical and anatomic patterns did not develop until after the contributions of the early modern neuroanatomists and physiologists in the first quarter of the nineteenth century. These contributions allowed the recognition of relatively distinct painful afflictions of the face, and permitted surgeons in the late nineteenth century to embark confidently on a variety of approaches to cranial and peripheral nerves using decompressive or destructive procedures to alleviate facial pain.

Cranial Nerve Diseases↗
PubMed2001

A history of brain imaging technology in neurosurgery.

In the closing decades of the nineteenth century, diagnosis of cerebral lesions was based on the clinical examination, and often the localization and operative approaches were based on observation of seizures. The attribution of certain symptoms and signs to dysfunction arising at an identifiable focal point in the brain was the basis for clinicopathologic correlation and rational treatment. As beautiful as brain anatomy was and as skillful as clinical examination could be, there was no means to produce images of a living patient that could be used to diagnose and treat that same patient. On November 8, 1895, all of this changed with Wilhelm Röntgen's discovery of X-rays. This article aims to elucidate seminal points in the history of medical imaging as applied to the brain that have had a major impact on neurosurgery.

Brain Diseases↗
PubMed2000

Using proton magnetic resonance spectroscopic imaging to predict in vivo the response of recurrent malignant gliomas to tamoxifen chemotherapy.

OBJECTIVE: Most patients with a malignant glioma spend considerable time on a treatment protocol before their response (or nonresponse) to the therapy can be determined. Because survival time in the absence of effective therapy is short, the ability to predict the potential chemosensitivity of individual brain tumors noninvasively would represent a significant advance in chemotherapy planning. METHODS: Using proton magnetic resonance spectroscopic imaging (1H MRSI), we studied 16 patients with a recurrent malignant glioma before and during treatment with high-dose orally administered tamoxifen. We evaluated whether 1H MRSI data could predict eventual therapeutic response to tamoxifen at the pretreatment and early treatment stages. RESULTS: Seven patients responded to tamoxifen therapy (three with glioblastomas multiforme; four with anaplastic astrocytomas), and nine did not (six with glioblastomas multiforme; three with anaplastic astrocytomas). Responders and nonresponders exhibited no differences in their age, sex, tumor type, mean tumor volume, mean Karnofsky scale score, mean number of weeks postradiotherapy, or mean amount of prior radiation exposure. Resonance profiles across the five metabolites measured on 1H MRSI spectra (choline-containing compounds, creatine and phosphocreatine, N-acetyl groups, lactate, and lipids) differed significantly between these two groups before and during treatment. Furthermore, linear discriminant analyses based on patients' in vivo biochemical information accurately predicted individual response to tamoxifen both before and at very early treatment stages (2 and 4 wk). Similar analyses based on patient sex, age, Karnofsky scale score, tumor type, and tumor volume could not reliably predict the response to tamoxifen treatment at the same time periods. CONCLUSION: It is possible to accurately predict the response of a tumor to tamoxifen on the basis of noninvasively acquired in vivo biochemical information. 1H MRSI has potential as a prognostic tool in the pharmacological treatment of recurrent malignant gliomas.

Administration, Oral↗
PubMed1999

Mercury water and cauterizing stones: Nicolas André and tic douloureux.

In his 1756 text, Observations pratiques sur les maladies de l'urèthre et sur plusiers faits convulsifs, Nicolas André coined the term "tic douloureux." He believed that this pain originated from compression of facial sensory peripheral nerves. Using scientific observation and experimentation to confirm this hypothesis, he reproduced the tic pain and treated it by using careful efforts to remove adhesions from the nerve with a caustic solution of mercury water. Believing that recurrence of the pain was a result of early closure of the wound, with recompression of the nerve being the direct cause, André prevented recompression by ensuring open wound drainage. André's surgical technique of using cauterizing stones ensured that there was minimal blood loss and little danger of rebleeding and recompression of the nerve by an accumulated blood clot. His case reports include lengthy follow-up periods that documented the benefits of his procedures, which were confirmed by testimonials from uninvolved colleagues. Although remembered for the two words, "tic douloureux," Nicolas André has long been ignored for his prescient treatment and scientific analysis of a disease for which the modern standard of care has only been defined during the last generation.

Cautery↗
PubMed1998

In vivo differentiation of astrocytic brain tumors and isolated demyelinating lesions of the type seen in multiple sclerosis using 1H magnetic resonance spectroscopic imaging.

We used computer pattern recognition of proton magnetic resonance spectroscopic image data to differentiate between brain tumors and large, isolated, demyelinating lesions of the type seen in multiple sclerosis. Leave-one-out linear discriminant analyses correctly classified resonance profiles from five acute demyelinating lesions, 20 low-grade astrocytomas, 22 anoplastic astrocytomas, and 24 glioblastomas. Classification of nonacute lesions will require further development, as the metabolic profiles of demyelinating lesions evolve over time.

Adult↗
PubMed1998

Magnetic resonance spectroscopy guided brain tumor resection: differentiation between recurrent glioma and radiation change in two diagnostically difficult cases.

BACKGROUND: It is often difficult to differentiate a recurrent glioma from the effects of post-operative radiotherapy by means of conventional neurodiagnostic imaging. Proton magnetic resonance spectroscopic imaging (1H-MRSI), that allows in vivo measurements of the concentration of brain metabolites such as choline-containing phospholipids (Cho), may provide in vivo biochemical information helpful in distinguishing areas of tumor recurrence from areas of radiation effect. PATIENTS AND METHODS: Two patients who had undergone resection and post-operative radiotherapy for a cerebral glioma became newly symptomatic. Computed tomographic (CT) and magnetic resonance imaging (MRI) performed after the intravenous infusion of contrast material, and in one case, [18F]fluorodeoxyglucose positron emission tomography (PET), could not differentiate between the possibilities of recurrent glioma and radiation effect. The patients underwent 1H-MRSI prior to reoperation and the 1H-MRSI results were compared to histological findings originating from the same locations. RESULTS: A high Cho signal measured by 1H-MRSI was seen in areas of histologically-proven dense tumor recurrence, while low Cho signal was present where radiation changes predominated. CONCLUSIONS: The differentiation between the recurrence of a cerebral glioma and the effects of post-operative irradiation was achieved using 1H-MRSI in these two patients whose conventional neurodiagnostic imaging was equivocal for such a distinction. Where these two conditions are present, metabolite images from 1H-MRSI, such as that based on Cho, can be co-registered with other imaging modalities such as MRI and may also be integrated with functional MRI or functional PET within a multimodal imaging-guided surgical navigation system to assure maximal resection of recurrent tumor while minimizing the risk of added neurological damage.

Adult↗
PubMed1998

Intracranial aneurysms and sickle cell anemia: multiplicity and propensity for the vertebrobasilar territory.

OBJECTIVE: We describe a case of sickle cell anemia and multiple intracranial aneurysms and review the English-language-reported cases of sickle cell disease associated with intracranial aneurysms proven angiographically or by autopsy, to assess whether there are associations with aneurysm multiplicity and sites of aneurysm occurrence. CLINICAL PRESENTATION: A 28-year-old woman with sickle cell disease and a subarachnoid hemorrhage underwent successful clipping of three intracranial aneurysms. RESULTS: Among 44 reviewed cases, 57% of patients demonstrated multiple aneurysms, and aneurysms from patients with multiple aneurysms comprised nearly 80% of the total number of aneurysms. There were, on average, three aneurysms per patient for patients with multiple aneurysms. There was a predominance of female patients (female/male ratio, 1.6:1), although there existed no significant differences in age or gender for patients with single or multiple aneurysms. None of the patients with multiple aneurysms was older than 40 years of age at the time of presentation. Patients with multiple aneurysms and sickle cell disease showed a significant difference in the distribution of the aneurysm sites, with a significantly large number occurring in the vertebrobasilar axis. Multiple aneurysms associated with sickle cell disease showed a higher rate of simultaneous occurrence in the posterior and anterior circulation, compared with multiple aneurysms in the general population. CONCLUSION: There are strong statistical associations for aneurysm multiplicity and sites of aneurysm occurrence among reported patients with sickle cell disease. Patients with sickle cell anemia and neurological symptoms should undergo magnetic resonance angiography or four-vessel angiography to detect potentially harmful, but neurosurgically treatable, pathological conditions.

Adolescent↗
PubMed1998

Arthur Roland Elvidge (1899-1985): contributions to the diagnosis of brain tumors and cerebrovascular disease.

The contributions of Arthur Elvidge (1899-1985), Wilder Penfield's first neurosurgical recruit, to the development of neurosurgery have been relatively neglected, although his work in brain tumors extended the previous work of Percival Bailey and Harvey Cushing. He published rigorous correlations of clinical and histological information and formulated a revised, modern nosology for neuroepithelial tumors, including a modern histological definition of glioblastoma multiforme. Well ahead of his time, he believed that glioblastoma was not strictly localized and was the first to comment that the tumor frequently showed "satellitosis." He was the first neurosurgeon in North America to use angiography as a radiographic aid in the diagnosis of cerebrovascular disease. Having studied with Egas Moniz, he was the first to detail the use of angiographic examinations specifically for demonstrating cerebrovascular disorders, believing that it would make possible routine surgery of the intracranial blood vessels. Seeking to visualize all phases of angiography, he was the impetus behind the design of one of the first semi-automatic film changers. Elvidge and Egas Moniz made the first observations on thrombosis of the carotid vessels independently of each other. Elvidge elucidated the significance of embolic stroke and commented on the ischemic sequelae of subarachnoid hemorrhage. Besides his contributions to neurosurgery, he codiscovered the mode of transmission of poliomyelitis. Elvidge's soft-spoken manner, his dry wit and candor, mastery of the understatement, love of exotic travel, and consummate dedication to neurosurgery made him a favorite of patients, neurosurgery residents, nurses, and other hospital staff. His accomplishments and example as teacher and physician have become part of neurosurgery's growing legacy.

Brain Neoplasms↗
PubMed1997

Function and organization in dysgenic cortex. Case report.

Cerebral dysgenesis is a subject of interest because of its relationship to cerebral development and dysfunction and to epilepsy. The authors present a detailed study of a 16-year-old boy who underwent surgery for a severe seizure disorder. This patient had dysgenesis of the right hemisphere, which was composed of a giant central frontoparietal nodular gray matter heterotopia with overlying large islands of cortical dysplasia around a displaced central fissure. Exceptional insight into the function, biochemistry, electrophysiology, and histological structure of this lesion was obtained from neurological studies that revealed complementary information: magnetic resonance (MR) imaging, [18]fluoro-2-deoxy-D-glucose positron emission tomography (PET), functional PET scanning, proton MR spectroscopic (1H-MRS) imaging, intraoperative cortical mapping and electrocorticography, in vitro electrophysiology, and immunocytochemistry. These studies demonstrated compensatory cortical reorganization and showed that large areas of heterotopia and cortical dysplasia in the central area may retain normal motor and sensory function despite strikingly altered cytoarchitectonic organization and neuronal metabolism. Such lesions necessitate appropriate functional imaging studies prior to surgery and cortical mapping to avoid creating neurological deficits. Integrated studies, such as PET, 1H-MRS imaging, cortical mapping, immunocytochemistry, and electrophysiology may provide information on the function of developmental disorders of cerebral organization.

Adolescent↗
PubMed1996

Accurate, noninvasive diagnosis of human brain tumors by using proton magnetic resonance spectroscopy.

Although conventional proton magnetic resonance imaging has increased our ability to detect brain tumors, it has not enhanced to nearly the same degree our ability to diagnose tumor type. Proton magnetic resonance spectroscopy is a safe, noninvasive means of performing biochemical analysis in vivo. Using this technique, we characterized and classified tissue from normal brains, as well as tissue from the five most common types of adult supratentorial brain tumors. These six tissue types differed in their pattern across the six metabolites measured. 'Leaving-one-out' linear discriminant analyses based on these resonance profiles correctly classified 104 of 105 spectra, and, whereas conventional preoperative clinical diagnosis misclassified 20 of 91 tumors, the linear discriminant analysis approach missed only 1. Thus, we have found that a pattern-recognition analysis of the biochemical information obtained from proton magnetic resonance spectroscopy can enable accurate, noninvasive diagnosis of the most prevalent types of supratentorial brain tumors.

Adult↗
PubMed1994

Lateralization of temporal lobe epilepsy based on regional metabolic abnormalities in proton magnetic resonance spectroscopic images.

Magnetic resonance spectroscopic imaging (MRSI) is capable of determining the spatial distribution in vivo of cerebral metabolites, including N-acetylaspartate (NAA), a compound found only in neurons. We used this technique in 10 patients with temporal lobe epilepsy (TLE) to determine the location of maximal neuronal/axonal loss or damage and to evaluate the potential of MRSI for presurgical lateralization. Asymmetry of the relative resonance intensity of NAA to creatine was determined for mid and posterior regions of the temporal lobes defined anatomically and also for "metabolic lesions" defined as the regions of maximal abnormality on MRSI. MRSI revealed decreased relative signal intensity in at least one temporal lobe of all patients. Two patients had a widespread reduction in NAA in both temporal lobes. The region of maximal abnormality was usually in the posterior temporal lobe but sometimes in the mid temporal lobe. The side of lowest NAA was ipsilateral to the clinical electroencephalographic lateralization in all patients. Lateralization based on NAA to creatine correlated with the atrophy of amygdala and hippocampus in 8 patients who showed this on magnetic resonance imaging volumetric measurements. MRSI can demonstrate regional neuronal loss or damage that correlates with clinical electroencephalographic and structural lateralization in temporal lobe epilepsy. The ability to identify a region of maximal metabolic abnormality on spectroscopic images may confer greater sensitivity than that available from single voxel methods. The maximal metabolic abnormality may not be located in a voxel defined a priori, and based on anatomical considerations, without knowledge of the distribution of the metabolic abnormality.

Adult↗
PubMed1994

Unusual evolution and computerized tomographic appearance of a gliosarcoma.

A patient with a remote infarct, seizures, mild hemiparesis, and dysphasia became obtunded over four months and died. Computerized tomography (CT) over 5 years showed a consistent, large, wedge-shaped left hemisphere hypodensity with a central calcification, but without signs of mass effect. This was interpreted as an infarct of the left middle cerebral artery territory. Post-mortem examination of the brain revealed the entire area appearing as infarct on CT was a gliosarcoma. We suspect that the unusual CT appearance of the lesion was likely caused by multiple pathologies: a low grade glioma transforming into a gliosarcoma that was able to spread throughout the area of infarct encephalomalacia without revealing a typical CT appearance of mass effect. The patient's brief period of deterioration probably coincided with transformation of the tumor into a gliosarcoma. The variable CT characteristics of gliosarcomas are reviewed.

Brain Neoplasms↗
PubMed1993

Spinal angiolipomas. Report of three cases.

Spinal angiolipomas are distinct, benign lesions composed of mature lipocytes admixed with abnormal blood vessels. Three new cases of spinal angiolipoma are presented and 34 previously reported cases are analyzed. The 37 total cases (23 females and 14 males) ranged in age from 17 to 73 years (mean 43 years; median 45 years). The mean age of the female patients was older than that for the males (45.0 vs. 41.6 years; p < 0.001, Student's t-test) and most were peri- or postmenopausal. Prior to diagnosis, 97% of the patients had weakness of the lower extremities, 94% had sensory dysfunction, 84% had hyperreflexia and spasticity, 51% had sphincter dysfunction, and 41% had back pain lasting from 1 to 180 months (mean 28 months). Five (22%) of the 23 female patients were pregnant and two had exhibited significant weight gain coincident with the onset of symptoms. The angiolipomas were extradural in 35 patients and intramedullary in two; seven of the extradural lesions infiltrated the surrounding bone. The tumors extended from C-6 to L-4 and had a predilection for the midthoracic region (53% of cases). Plain radiographs were abnormal in 11 (39%) of 28 patients and in all patients with bone infiltration. Myelograms were abnormal in 97% of 32 patients and showed a complete block in 63% of patients. Computerized tomography (CT) and magnetic resonance (MR) imaging revealed the fat-density lesions in all cases studied. There was vascular enhancement in three of five cases with contrast-infused CT and in the one case with gadolinium-infused MR imaging. All patients improved following resection of the epidural lesions and internal decompression of the intramedullary lesions. It is concluded that spinal angiolipomas predominantly affect women. They involve the thoracic (especially the midthoracic) region, and produce symptoms and signs of spinal compression and, in some cases, bone erosion and pathological fractures. Their symptomatology can be exacerbated by pregnancy and weight gain, suggesting that vascular engorgement and the presence of obesity influence their evolution. Their preponderance in older, peri-, or postmenopausal women, and their clinical exacerbation in pregnant women support a role for hormonal influence. Magnetic resonance imaging is the investigation of choice for the diagnosis of these lesions. Surgery is universally successful in relieving symptoms.

Adult↗
PubMed1993

Neurosurgeon as innovator: William V. Cone (1897-1959).

Neurosurgeons are well known for being productive researchers and innovators. Few, however, have possessed the prolific ingenuity of William Cone. In 1934, he and William Penfield were cofounders of the Montreal Neurological Institute where, until 1959, he filled the twin roles of neurosurgeon-in-chief and neuropathologist. Because he did not find writing easy, many of his technical inventions and refinements remained unpublished. His numerous innovations included the extensive use of twist-drill technique for biopsy, drainage for subdural hematoma and cerebral abscess, and ventriculography. In the mid-1940's, he developed power tools driven by nitrogen that led to the modern, universally used air-driven tool systems. He had a special interest in the treatment of spinal dysfunction, for which he invented the Cone-Barton skull-traction tongs along with the Cone spinal operating table. He also devised operative procedures for vertebral fracture-dislocation and craniospinal anomalies. For the maintenance of muscle tone in the paralyzed bladder, he constructed a tidal drainage system. He introduced and popularized ventriculoperitoneal shunting techniques and carried out some of the earliest experimental trails to treat brain infections with sulphonamide and antibiotic drugs. He designed his own set of surgical suction devices, bone rongeurs, and a personal suction "air-conditioning" system for each surgeon. He had a keen early interest in intracranial tumors, and also demonstrated on monkeys how subdural mass lesions caused pupillary dilation and mesial temporal lobe damage due to cerebral compression. His work for the military during World War II on effects of altitude on brain pressure remained classified for many years. The first clipping and excision of an intracranial aneurysm is attributed to Cone. Although Penfield was known as "the Chief," Cone was referred to as "the Boss." His fervent dedication to provide total care to his patients was expressed in round-the-clock vigils; he did not separate "nursing" from "surgical" care. Ultimately, Cone's driving passion for perfection led in part to his tragic death. His accomplishments, inventions, and his example as teacher and physician have become part of neurosurgery's collective legacy.

Canada↗