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P Page

Publications and source records attributed to P Page.

At least 19 recordsLinked to original sources
PubMed2001

[Cerebral arteriovenous malformations treated by radiosurgery: a series of 705 cases].

BACKGROUND AND PURPOSE: After a review of the main radiosurgical published series, to evaluate our own series of 705 patients with cerebral arteriovenous malformations treated by radiosurgery alone or in combination with embolization or surgery. PATIENTS: and method. From January 1984 to December 1998, 705 patients were treated by a multidisciplinary team including neurosurgeons, neuroradiologists, radiophysicians and radiotherapists. Age of revelation of the cerebral arteriovenous malformations ranged between birth to 73 years (mean 27, median 25). Age at time of radiosurgery ranged between 7 and 75 years (mean 33, median 31). There were 410 males for 295 females (sex- ratio 1.4). Symptoms of revelation were hemorrhage for 59%, seizures for 23%, headaches for 14% and progressive deficits for 4%. Discovery of cerebral arteriovenous malformation was fortuitous in 4% of cases. Repartition following Spetzler's grading was 12% in grade I, 36% in grade II, 40% in grade III, 12% in grade IV and 0% in grade V. Maximal size ranged between 4 and 60 mm (mean 23, median 20). Volume ranged between 0.2 and 24.3 cc (mean 3.8, median 2.8). Majority of cerebral arteriovenous malformations were large size (42% with size higher than 25 mm) and large volume (54% higher than 10 cc. 54% of patients had treatment prior radiosurgery: 38% had embolization, 10% were operated, 4% were treated by radiosurgery (reirradiation) and 3% were operated and embolized. RESULTS: Overall complete obliteration rate was 55%. The obliteration rate was correlated with size (77% for cAVMs lower than 15 mm, 62% for cerebral arteriovenous malformations between 15 and 25 mm, and 44% for cerebral arteriovenous malformations higher than 25 mm), with volume (94% for cerebral arteriovenous malformations lower than 1 cc, 64% between 1 and 4 cc, 48% between 4 and 10 cc, and 62% for cerebral arteriovenous malformations higher than 10 cc), dose at reference isodose, minimal dose, morphological parameters (presence of dural components, arteriolovenous fistula, plexiform angioarchitecture, arterial steal, arterial recruitment, deep exclusive drainage, venous plicature, venous confluence, venous ectasia, venous reflux), sectional topography and good recovery of the target. Embolization was a confusion factor not associated with obliteration rate. After multivariate analysis, only Dmin and complete coverage of the cerebral arteriovenous malformations were correlated with obliteration rate. Delay of obliteration was significantly correlated after multivariate analysis with Dmin, complete coverage, arteriolovenulary angioarchitecture (positive correlation) and venous ectasia (negative correlation). CONCLUSION: Overall complete obliteration rate is unreliable data to assess efficacy of radiosurgical method in the tretment of cerebral arteriovenous malformations. The obliteration rate must be interpretated after stratification on several morphological and dosimetric parameters.

Adolescent↗
PubMed2001

[Surgical removal of radio-induced lesions after radiosurgery of cerebral arteriovenous malformations].

Radioinduced lesions after radiosurgery of cerebral arteriovenous malformations may be associated with an increased signal on T2-weighted and gadolinium enhancement on T1-weighted MR images. They do not have necessarily a poor prognosis. These lesions are mostly asymptomatic. But in a few cases they can be associated with severe clinical symptoms which can become corticodependant or corticoresistant. We present the 5 cases of such cerebral arteriovenous malformations treated by radiosurgery, out of our series of 705 patients. The removal was easier than that of untreated cerebral arteriovenous malformations, and led to a complete recovery of symptoms and progressive decrease of imaging abnormalities. Such surgery should be proposed in case of symptomatic radioinduced lesions which fail to respond to steroids.

Adult↗
PubMed2001

[Evolution of epileptic seizures associated with cerebral arteriovenous malformations after radiosurgery].

The goal of this study is to evaluate the response of epileptic seizures associated with cerebral arteriovenous malformations following radiosurgery and determine the factors associated with a positive outcome. The series included 210 patients (123 men, 87 women) with a mean age of 33. One hundred seventy three patients out of 210 were controlled after radiosurgery. Seizures completely disappeared in 58% of cases and decreased in 18%. Anti-epileptic treatment was stopped in 44%. Sex and age upon seizure appearance were not found as determining factors in patients whose seizures disappeared after radiosurgery. Generalized seizures disappeared following radiosurgery in 90.7%, partial secondary generalized seizures in 53.5%, and partial seizures in only 39.6%. Frontal or temporal malformations are associated with a better response after radiosurgery than sylvian or rolandic location. Seizure disappearance was maximal in case of isolated seizure prior to the radiosurgery (84.4%), was reduced to 61.2% when seizures were limited to 2 to 20, and disappeared in 21.4% in severe seizures. Epilepsy present less than 3 years prior to radiosurgery disappeared in 71.9%; was reduced to 45% when the delay was over 3 years. Seizures disappeared in 64.4% when the malformation was obliterated, they were reduced to 46.9% when malformations persisted. The persistence of severe seizures following radiosurgery was linked to persistence of the malformation. On the other hand early seizures occurred in 3.3% during the first 48 hours following radiosurgery; they disappeared in 72.2% after that period. De novo seizures also occurred in 1.7% and disappeared in all these cases. In conclusion, seizures associated with cerebral arteriovenous malformations respond well to radiosurgery; the malformation obliteration evokes its association with the seizure; the seizure disappearance in spite of persistence of the malformation evokes the positive effect of radiotherapy on epileptic seizures.

Adolescent↗
PubMed2001

[Course of headaches associated with cAVMs after radiosurgery].

The purpose of this study is to evaluate the response of headaches associated with cerebral arteriovenous malformations following radiosurgery and determine the factors that are associated with a positive outcome. From our series of 700 patients whose cAVM was treated by radiosurgery, this study includes 109 patients (48 males, 61 females) with a mean age of 32 when radiosurgery was performed. Headaches resolved in 37 patients (53.7%), decreased in 14 patients (20.3%), persisted in 16 patients (23.2%), and even increased in frequency in 2 (2.9%). Headaches disappeared 2 years following radiosurgery in the majority of patients (31 out of 37: 83.3%). The disappearance rate of headaches was better when it was the only sign of the malformation (64%) or preceded an epileptic seizure (60%) with respect to the case when it preceded cerebral hemorrhage (34.8%). Headaches having the best response were those with 1 to 2 episodes per month (64.9%) and whose episode duration was less than 3 hours (67.6%). Unilateral headaches accounted for 86.5% of resolved headaches whereas bilateral headaches were only 8.1% and even less were the diffuse ones (5.4%). The best evolution was obtained for those associated with a parietal location of the cerebral arteriovenous malformation, followed by rolandic (respectively 55.5% and 50%). Occipital malformation was associated with headache disappearance in 38.1% and temporal with 34.3%, whereas frontal location was associated with headache disappearance in only 25% of the cases. Headache disappearance was often correlated with cerebral arteriovenous malformation outcome after radiosurgery (64.9% of disappearance in case of complete obliteration). However, in 24.8%, headaches disappeared prior to the malformation obliteration and were associated with a decrease of the flow, of the nidus volume or with the nidus disappearance with the persistence of a precocious venous drainage. Headaches disappeared in spite of the malformation persistence in 5.4% of the cases. We found de novo headaches in one patient one year following RS. Another patient presented an episode of headache 12 hours following RS. The course of headaches associated with cerebral arteriovenous malformations after radiosurgery is positive in the majority of cases and correlated to the malformation outcome. This correlation suggests a link between cerebral arteriovenous malformations and headaches and the equal benefit of radiosurgery on both of them.

Adolescent↗
PubMed1999

Subcranial fronto-orbito-nasal approach for ethmoidal cancers surgical techniques and results.

BACKGROUND: The authors report their experience with the subfronto-orbito-nasal approach (SFON) for the treatment of 30 patients suffering from ethmoidal cancers over the past 3 years. The advantages and pitfalls of this technique are described and compared with other classic approaches. METHODS: Among 156 patients suffering from ethmoidal cancers and treated between January 1984 and January 1998, 30 patients were operated on using the SFON approach during the past 3 years. There were 27 males and 3 females, ranging in age from 15 to 77 years. Histologic composition of the lesions was as follows: 15 adenocarcinomas, 6 esthesioneuroblastomas, 3 melanomas, 2 epidermoid carcinomas, 1 nondifferentiated carcinoma, 1 neuroendocrine carcinoma, 1 villous carcinoma, and 1 cystic adenoid carcinoma (cylindroma). According to the authors' classification, 7% were T1, 6% T2, 22% T3, 38.5% T4a, and 26.5% T4b. All patients were operated on through a SFON approach, followed by removal of the tumor and reconstruction of the skull base with a pericranial flap. RESULTS: Since the mean follow-up was of short duration (12 months, ranging from 3 to 29 months), significant carcinologic results could not be obtained. However, a detailed analysis of the surgical procedure was performed. No patient died or had major complications related to the SFON approach. One cerebrospinal fluid (CSF) fistula and four oculomotricity dysfunctions were observed. Definitive anosmia was reported in all cases. CONCLUSION: The advantages of the procedure include a wide exposure of the anterior skull base through a limited approach, the possibility of modifying the approach according to the size and location of the lesion, total resection of tumors, simplified skull base reconstruction technique, and reduction of postoperative confusion and hospital stay.

Adolescent↗
PubMed1999

Synthesis of phosphono analogues of dihydroxyacetone phosphate and glyceraldehyde 3-phosphate.

The present paper describes the synthetic routes of six phosphono analogues of dihydroxyacetone phosphate and five phosphono analogues of glyceraldehyde 3-phosphate through alpha-, beta- and gamma-hydroxyphosphonate esters precursors containing a protected carbonyl group. In some situations, depending on the sequence used for the deprotection of the phosphonate and carbonyl groups, the aldol/ketol rearrangement allowed the synthesis of either dihydroxyacetone phosphate or glyceraldehyde 3-phosphate analogues from the same precursors. All these analogues are of interest both as active-site probes and as potential substrates for glycolytic enzymes such as fructose 1,6-diphosphate aldolases (EC 4.1.2.13).

Animals↗
PubMed1999

[Cauda equina tumors in adults].

Large series of cauda equina tumors in adults are seldom reported. This study was based on the 231 cases collected in the French neurosurgery units for the congress of the Société Française de Neurochirurgie in October 1996. Schwannomas were the most frequent benign tumor in this series, followed by ependymomas. Very few malignant tumors were recorded, usually malignant neurinomas nearly always arising in patients with neurofibromatosis. Some other rare tumors were also observed including paragangliomas. This series confirms the contribution of pre-therapeutic neurological status to functional prognosis. All schwannomas can be cured while ependymomas and paragangliomas may recur after a very long delay. Surgery must be as complete as possible since adjuvant therapies have proven to have little efficacy. This type of tumor requires a very long follow-up. Prognosis is good for hemangioblastoma. When present, abnormal sphincter function is an argument for poor prognosis. It may appear after primary surgery or more often after treatment of recurrence.

Adult↗
PubMed1999

Quality of care-risk adjustment outcomes model: testing the effects of a community-based educational self-management program for children with asthma.

This article describes the design of an outcomes model incorporating adjustment for patients' risks for various outcomes of care. A community-based educational self-management program for children with asthma is proposed for testing the model. Measures of model components: clinical factors; nonclinical factors; psychological, cognitive, and psychosocial functioning; and patient and client satisfaction are described. Testing this model has implications for guiding the development of individualized culturally sensitive nursing interventions for children with asthma and their parents.

Adolescent↗
PubMed1998

Interaction of phosphonomethyl analog of dihydroxyacetone phosphate with rabbit muscle aldolase.

Aldolase presents the same binding affinity for dihydroxyacetone phosphate and its phosphonomethyl analog, but the partition coefficient between the intermediates from the Michaelis complex to the eneamine is different. The effects of the structural modification of the triose phosphate substrate on the interaction with rabbit muscle aldolase are discussed in connection with the mechanistic pathway and the three-dimensional structure of the enzyme.

Animals↗
PubMed1998

The synthesis of symmetrical spermine conjugates using solid-phase chemistry.

The utility of spermine, selectively functionalised and immobilised on a solid support by means of the Wang "oxycarbonyl" linker is demonstrated by the solid-phase synthesis of a number of spermine conjugates including the natural product and potent antihypertensive agent kukoamine. The synthesis opens up the area of solid-phase spermine chemistry and library generation based on the symmetrical spermine scaffold.

Chromatography, High Pressure Liquid↗
PubMed1998

[The place of radiosurgery in the treatment of hypophyseal adenoma].

Since 1984, the neurosurgical team of Sainte-Anne Hospital in Paris has taken in charge almost 750 patients for linear accelerator radiosurgery. But only a small percentage of them were harbouring a pituitary tumor. That is why the present paper is based mostly on literature data. Pituitary adenoma radiosurgery (RS) is a second intention therapeutic method. It should be recommended only after failure of medical and/or surgical treatment. Two main methods can be used: linear accelerator-radiosurgery and Cobalt-60 gamma unit. Both procedures provide equivalent results in terms of dosimetry, accuracy and clinical data. Results of various series presented in recent and updated literature have been studied and analysed. They show and confirm the efficiency of radiosurgery on tumor and hormone secretion controls, with few cases of pituitary insufficiency. However, results were disappointing concerning visual disorders, particularly if visual dysfunction and impairment existed before radiosurgery. All authors agree nowadays on different points: a) indications: invasive adenomas, with an incomplete resection, or adenomatous recurrences, b) contraindications: tumoral size > 20 mm, distance to visual pathways < 5 mm, c) imperative precautionary measures: less than 8 Gray must be delivered on visual pathways, less than 40 Gray on oculomotor nerves. In some cases, stereotactic fractioned radiotherapy may be an alternative treatment for large tumors close to visual pathways.

Adenoma↗
PubMed1998

[Intracavernous extension of hypophyseal macroadenomas: infiltration or invagination?].

Frequency of intracavernous invasion by a pituitary adenoma varies from 9% to 40% depending on the publications. Without putting off the possibility of true intracavernous invasion, it seems less frequent than evocated on CT-Scan and/or MRI data. We studied 153 files of pituitary adenomas operated upon recently: 72 prolactinomas (47.3%), 30 GH-secreting adenomas (19.7%), 7 corticotrop adenomas (4.6%), 44 non secreting adenomas (28.3%). 108 patients (70.4%) harboured a macroadenoma (diameter > 10 mm). A suprasellar expansion was seen 90 times on CT-Scan and/or MRI views. 19 times (17.7% of macroadenomas, 12.5% of the whole series) MRI evocated an infiltration of one or both cavernous sinuses (CS). Such data were found 3 times before 1991, 16 times since 1991, i.e. since MRI is systematically performed preoperatively. Except in two patients who respectively presented with a large intraorbital or temporal expansion, we have not been able to confirm the reality of the intracavernous invasion. We think that most of CT-Scan or MRI data of so-called intracavernous invasion correspond in fact to a compression or to a fingerglove invagination of the medial wall of the CS. In fact, anatomical studies by Harris & Rhoton (1976) and by Taptas (1990) demonstrated that such an invagination of the medial wall exists in almost one third of normal pituitary glands. These data must bring up to much carefulness when considering a possible pathological CS invasion by a macroadenoma. Therefore, it should be thoroughly assessed with anatomoradiological and radio-surgical correlations.

Adenoma↗
PubMed1998

[Controversies in the management of operated pituitary macroadenomas].

BACKGROUND AND PURPOSE: Complete resection of a pituitary adenoma is feasible in almost 50 to 70% of cases. Dealing with the remnant is still controversial. Three positions can be discussed: second stage operation, radiation therapy, clinical and radiological follow-up. METHODS: Among 108 pituitary macroadenomas operated on during the last 10 years, 54 patients (50%) with partially removed tumors were studied. Three cases best illustrating the evolution of these remnants are reported. RESULTS: Late MRI performed 4 to 6 months postoperatively is more valuable than early MRI in the evaluation of these remnants, which can remain stable for a long period of time without any adjuvant treatment. CONCLUSION: MRI should be performed 4 to 6 months postoperatively. Rather than performing radiation therapy systematically for asymptomatic patients, these patients should be followed up at regular intervals and treated only in case of regrowth of the tumor.

Adenoma↗
PubMed1997

[Prognostic factors and primary cerebral lymphoma].

Therapeutic results of 248 patients with primary central nervous system lymphoma reported in the SFNC series between 1980 and 1995 were analyzed. Clinical, biological and radiological prognostic factors were found to have a favorable impact on survival: a) age < 60 years; b) radiation therapy but without evidence of a dose-response relationship; c) radiation therapy in addition to chemotherapy; d) the use of systemic chemotherapy consisting of anthracyclines. In multivariate analysis, we identified 4 independent factors: a) radiotherapy (RR = 3), b) age (RR = 2.31), c) the use of chemotherapy consisting of anthracyclines (RR = 2.53), d) partial surgical resection but as an unfavourable prognostic factor (RR = 1.45).

Age Factors↗
PubMed1995

[Identification of deep septal ventricular tachycardia substrates from epicardial breakthrough characteristics].

This study aimed to elucidate the relationship between the epicardial activation pattern and the site of origin of the ventricular tachycardia (VT) occurring from the interventricular septum, and to find epicardial breakthrough characteristics identifying VT substrates. Seven patients undergoing intraoperative mapping including right ventricular endocardial mapping were studied. Thirteen septal VTs, which were defined as VTs in which both right and left ventricular endocardial breakthroughs were on the septal aspect, were induced. The VT site of origin was identified from the site and timing of right and left septal endocardial breakthroughs. All VTs were classified into three groups according to the site of epicardial breakthrough: type A, epicardial breakthrough in the anterior interventricular area; type F, epicardial breakthrough in the right ventricular free wall; type P, epicardial breakthrough in the posterior interventricular area. All type F VTs had a right ventricular endocardial breakthrough in the anterior septum and preceded the left ventricular endocardial breakthrough, thereby indicating right anterior septal origin. In the types A and P, both the right and left endocardial breakthroughs were localized in consistent (anterior and posterior, respectively) halves of the septum, but their relative timing was inconstant. This result suggests that epicardial mapping, and even noninvasive methods like body surface mapping, can identify the site of origin of the septal VTs, especially when the epicardial breakthrough occurs in the right ventricular free wall.

Aged↗