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P Derome

Publications and source records attributed to P Derome.

At least 19 recordsLinked to original sources
PubMed1998

[A peculiar mechanism of hydrocephalus: the "water-hammering" effect].

BACKGROUND AND PURPOSE: Aneurysms of the basilar artery can cause hydrocephalus due to compression of the third ventricle or the sylvian aqueduct. The observation of a particular case led to discuss another possible mechanism of hydrocephalus. CLINICAL PRESENTATION AND RADIOLOGICAL STUDIES: An aneurysm of the basilar artery was revealed by an ischemic stroke in a 65-year-old man. Hydrocephalus developed during the following months. The MRI studies showed that it could not be explained merely by a permanent compression. However, the patient improved clearly after a ventriculo-peritoneal derivation. CONCLUSION: The hydrocephalus could be explained by a "water-hammering" effect due to the pulsating blood in the ectatic vessel, which created a cerebrospinal fluid outflow impairment through the third ventricle.

Aged↗
PubMed1997

[Cushing disease in children and in adolescents. Therapeutic results].

BACKGROUND: Trans-sphenoidal surgery is currently the treatment of choice for Cushing's disease in children. PATIENTS AND METHODS: The results obtained in 20 consecutive patients referred to the Pediatric Endocrinology Department of hôpital Saint-Vincent-de-Paul are reported. RESULTS: A remission of Cushing's disease was observed in 12/16 (75%) patients in whom surgery was the first treatment. Among these 12 patients, three relapsed (25%) 21 to 80 months after surgery. Four patients were initially treated with steroid synthesis inhibitors: three of those patients were subsequently operated on and their disease remitted. Among the seven patients in whom surgery failed (primary failure or relapse), two were reoperated and also remitted. Taken together, 21 operations were performed and resulted in four immediate failures (19%), three relapses (14%) and 14 long-term remissions (67%, follow-up 40 +/- 35 months). None of the biological, radiological or operative criteria were predictive of the therapeutic results. CONCLUSION: Our results illustrate the efficacy and limits of trans-sphenoidal surgery for Cushing's disease of children and emphasize the need for a very long follow-up of these patients. Treatment of patients in whom surgery has failed (initially or secondarily) is particularly difficult and requires a multidisciplinary approach.

Adenoma, Basophil↗
PubMed1997

[Late cerebral radionecrosis of cystic aspect].

Two cases of delayed cerebral radionecrosis with cystic presentation are reported. The patients had received radiation therapy for a cutaneous tumor 16 and 12 years before. Surgical extirpation of the cerebral lesion permitted to confirm the diagnosis and to treat the patients with success. A cystic aspect has been reported rarely in the neuroradiologic descriptions of the cerebral radionecrosis in the literature. Its mechanism is discussed. The treatment of the delayed cerebral radionecrosis is not clearly established, but a cystic presentation is an argument for surgery.

Adult↗
PubMed1997

Unusual scotomas after transsphenoidal surgery of a pituitary macroadenoma.

The case of a woman presenting unusual bilateral campimetric defects following transphenoidal surgery is presented. The defects, consisting of a necklace of small round scotomas, disappeared after a corticosteroid treatment. A postoperative inflammatory mechanism may explain these unusual visual field abnormalities.

Adenoma↗
PubMed1996

Adenomatous transformation of the human anterior pituitary is associated with alterations in integrin expression.

Integrins are heterodimeric transmembrane molecules that mediate cell-cell and cell-substratum adhesion. Because alterations in the adhesive properties of tumor cells influence tumor growth and progression, the distribution of different alpha and beta integrin subunits was studied in both the parenchyma and the connective tissue in 6 normal and 25 adenomatous human anterior pituitaries. All normal parenchymal cells expressed the alpha3beta1 and alpha6beta4 integrins. By contrast, in adenomatous parenchymal cells the expression of alpha3beta1 was down-regulated and that of alpha6beta4 abrogated. Neoexpression of alphavbeta3 Occurred in the parenchyma of a subset of adenomas. All normal connective tissue cells expressed the alpha1 and beta1 subunits, a third subunit (alpha5) being present in the normal endothelium. By comparison, all adenomatous stromal cells expressed many more integrin subunits (alpha1, alpha3, alpha5, alphav, beta1 and beta3), adenomatous endothelial cells bearing additional subunits (alpha6, beta4 and beta5). Vitronectin, absent from the normal connective tissue, was constantly observed in the adenomatous stroma. To conclude, compared with cells of the normal gland, adenomatous anterior pituitary cells display a decreased expression of integrins whereas the adenomatous stroma expresses a rich repertoire of integrins. These changes are not related to the secretory type, grade or invasiveness of the adenoma. The resulting alterations in the adhesive properties of adenomatous cells could facilitate their dissemination. Enrichment of the integrin repertoire expressed by the adenomatous vasculature is indicative of its dual nature, systemic and tumoral.

Adenoma↗
PubMed1996

Treatment of Cushing's disease by transsphenoidal, pituitary microsurgery: prognosis factors and long-term follow-up.

Transsphenoidal pituitary microsurgery is considered as the best treatment of Cushing's disease. However, some recent studies reported disappointing results, leading their authors to suggest the possibility of returning to a first line adrenalectomy treatment. The aim of this study was to evaluate long-term results of transsphenoidal surgery in Cushing's disease, with special interest in factors that could affect the surgical outcome on the one hand and particular attention to surgical endocrine effects on the other. Fifty consecutive patients (34 females, 16 males, mean age 29.64 +/- 1.52 yr) were studied. The median post-operative follow-up was 71.5 months (range 25-219). Clinical, biological, surgical and pathological data between the success and failure groups were compared. Criteria of cure were: normal urinary free cortisol excretion, circadian cortisol rhythm and low dose dexamethasone test. Recovery of corticotroph and somatotroph functions were followed using the insulin test. Particular attention is given to clinical evolution in evaluating other pituitary functions. T4 or FT4, prolactin, E2 in women, testosterone in men, were measured. TRH and LHRH tests were not systematically performed. Only two parameters differed significantly between the cured and failure groups: the size of the adenomas was smaller and the pathological confirmation of the adenoma more frequent in the cured group. One patient had permanent corticotropic failure while two other had impaired response to hypoglycemia with normal cortisol basal levels. No acquired hypothyroidism nor hypogonadism were observed except in a patient who underwent two operations and radiotherapy. Recovery of GH function was slow. Definitive short stature was observed in all the patients whose disease began before the age of 16. Two patients had permanent diabetes insipidus. In conclusion, the most favorable prognosis in transsphenoidal surgery for Cushing's disease is observed in case of microadenoma confirmed by pathological examination. With this treatment, we obtained satisfactory results in Cushing's disease with minimal complications and no necessity of life-long endocrine substitutive therapy.

Adenoma↗
PubMed1996

[Frontal mucoceles of orbital or cerebral extension: therapeutic strategy].

The aim of this study was to investigate ten patients who underwent surgery for mucoceles of the frontal sinus. Bicoronal direct access was required by the localization of the mucocele limited to the frontal sinuses, its extension to the orbit and/or the brain and because of the anatomy of the frontal sinuses (large size, lateral horn...) as evidenced at imaging. Direct access to the frontal sinuses was achieved in 9 patients allowing marsupialization associated with repermeabilization of the naso-frontal duct (7 cases) or exeresis of the mucocele by cranialization (2 cases). Mean follow-up is 27 months. Repermeabilization of the naso-frontal duct was effective in 7 out of 8 cases. There were no complications after cranialization and no recurrence has been observed. Drainage of frontal mucoceles is a first intention strategy. In case of complication or recurrence, cranialization of the frontal sinuses would appear to be better than an exclusion-filling procedure.

Adult↗
PubMed1995

Fibronectin isoforms are differentially expressed in normal and adenomatous human anterior pituitaries.

The expression of fibronectin (FN) isoforms containing the extradomains A and B (ED-A+ and ED-B+ FNs) as well as a differentially O-glycosylated oncofetal form of the protein (onf-FN) was investigated in 6 normal human anterior pituitaries and 25 human pituitary adenomas. In normal tissue, immunohistochemical experiments showed the presence of FN molecules lacking the extradomains A and B (ED-A- and ED-B- FNs) without onf-FN immunoreactivity. These proteins were localized in the connective tissue compartment and especially in the vessel walls. Analysis of FN mRNA demonstrated an in situ synthesis of ED-A- and ED-B- FNs in the normal anterior pituitary. By contrast, in the adenomas, immunoreactivity for ED-A+ FN was observed in all cases. ED-B+ and onf-FN immunoreactivities were observed in 14 and 8 adenomas, respectively, regardless of the type, grade or invasiveness of the adenomas. ED-A+ FN mRNA was expressed in all adenomas studied, and ED-B+ FN mRNA was present in ED-B+ immunoreactive cases only. In pituitary adenomas, these 3 forms of FN were specifically associated with the endothelium and vascular smooth-muscle cells. Our results demonstrate that the processes of remodelling of the connective tissue compartment that occur in adenoma angiogenesis are associated with pre- and post-translational alterations of FN synthesis leading to the expression of ED-A+, ED-B+ and oncofetal FNs.

Adenoma↗
PubMed1995

Fluconazole penetration in cerebral parenchyma in humans at steady state.

We studied fluconazole penetration in the brain in five patients who had a deep cerebral tumor whose removal required the excision of healthy brain tissue. Plasma and brain samples were simultaneously obtained after oral ingestion of 400 mg of fluconazole daily for 4 days (90% of steady state). Fluconazole penetration in healthy cerebral parenchyma was determined. Plasma and brain samples were assayed by high-pressure liquid chromatography. Concentrations in plasma and brain tissue were 13.5 +/- 5.5 micrograms/ml and 17.6 +/- 6.6 micrograms/g, respectively. The average ratio of concentrations in the brain and plasma (four patients) was 1.33 (range, 0.70 to 2.39). Despite the lack of data concerning the penetration of fluconazole in brain abscesses, these results should permit the use of a daily dose of 400 mg of fluconazole in prospective clinical studies that evaluate the effectiveness of this drug in the treatment of brain abscesses due to susceptible species of fungi.

Adult↗
PubMed1995

[Surgical anatomy of the parathyroid glands. Apropos of 200 cases. Practical implications].

An operative procedure aimed at decreasing the risk of post-surgery hypothyroidism was proposed on the basis of parathyroid gland surgical anatomy described from a retrospective study of 200 thyroidectomies performed by the same operator It is almost always possible to visualize 1 or parathyroids during thyroid procedures. This fact makes it possible to reduce the rate of definitive hypoparathyroidism to less than 5% in surgery for invasive cancer of the thyroid and to 1% for non-invasive cancers requiring total thyroidectomy and uni or bilateral mediastinorecurrent curettage.

Humans↗
PubMed1994

Interactions between normal and tumoral tissues at the boundary of human anterior pituitary adenomas. An immunohistochemical study.

We studied the boundary between adenoma and peritumoral anterior pituitary tissues in order to understand their mutual interactions during tumour progression. We selected 18 adenomas of different secretory type, grade and invasiveness in which fragments of peritumoral anterior pituitary were still attached to the adenoma. Immunohistochemistry was performed on serial sections with markers of the basement membranes (type IV collagen), the hormone-producing cells of the normal and neoplastic anterior pituitary, and the folliculo-stellate cells (S-100 protein). In passing from tumour to gland, localized areas of passive compression of the normal gland were seen in only 3 cases. In all the tumours, the boundary consisted partly or solely of a transitional zone characterized by the presence of enlarged cell-cords. Openings in the basement membrane of these enlarged cell-cords were seen in contact with the tumour tissue. Normal and neoplastic cells intermingled in the transitional zone. Normal residual cells could be seen in the central area of the tumour but no adenomatous cells were observed in the gland around the tumour. Folliculo-stellate cells were concentrated in the vicinity of the transition zone. These findings favour the existence of an active process of adenoma expansion within the normal parenchyma, without noticeable infiltration of tumour cells into surrounding gland.

Adenoma↗
PubMed1994

Transsphenoidal surgery for pituitary adenomas in children.

The authors have reviewed the results of transsphenoidal surgery for pituitary adenomas done on 66 children (younger than 16 yr of age) between 1966 and 1992. Ninety-four percent (62 of 66) showed clinical evidence of pituitary hormonal hypersecretion. The most common type was the adrenocorticotropic hormone-secreting adenoma (n = 36), followed by the prolactinoma (n = 18) and the growth hormone-secreting types (n = 8). There were four cases of nonfunctioning adenomas. Adrenocorticotropic hormone-secreting tumors in children had presentations and surgical results similar to those seen in adults. Twenty-three of 33 patients with Cushing's disease had simple adenomectomy or subtotal hypophysectomy without symptomatic recurrence. Four of 10 initial treatment failures had subsequent successful surgical intervention, resulting in an overall cure rate of 78%. Postoperative hypocortisolism was suggestive of surgical success but was not absolute. Of three patients with Nelson syndrome, none were successfully treated with surgery alone and two developed invasive disease. Prolactin-secreting and growth hormone-secreting tumors in children occurred more commonly with suprasellar expansion than did their adult counterparts. Transsphenoidal surgery was capable of controlling disease in only 12% (1 of 8) of growth hormone-secreting tumors, and 67% (12 of 18) of prolactin-secreting tumors required postoperative medical therapy or radiotherapy for persistently elevated prolactin levels. Special difficulty was noted in boys with prolactinomas and in girls with primary amenorrhea. As in adults, preoperative prolactin levels correlated with ultimate surgical success rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1994

Immunohistochemical localization of different laminin isoforms in human normal and adenomatous anterior pituitary.

BACKGROUND: Laminin (LM) is an integral component of basement membranes (BM), with important roles in various aspects of cell biology. Several different isoforms of LM have been described, and each comprises a molecule consisting of three subunit polypeptides, the A, B1, B2, M or S chain. EXPERIMENTAL DESIGN: The distribution of different LM subunits was studied in human nontumoral anterior pituitaries obtained postmortem and in pituitary adenomas by immunocytochemical methods using specific monoclonal antibodies. RESULTS: In normal tissue, the A, B1, and B2 chains had a ubiquitous localization in both parenchymatous and vascular BMs and in the pericapillary connective tissue space also. The S chain seemed to have principally a vascular localization, in contrast to the M chain that was mostly localized in the parenchymatous BM. The same antigens were investigated in 23 human pituitary adenomas of different secretory type, grade and invasiveness. In all cases, the five monoclonal antibodies gave a positive staining. The presence or the localization of LM chains did not display a specific pattern in the adenomas according to their secretory type, grade or extent of local invasion. In the adenomas, the anti-A, -B1, and -B2 monoclonal antibodies stained the stroma and in particular the vascular BMs as well as the sparse elements of parenchymatous BMs when they were present. The staining with anti-S antibody was localized in the stroma and around all the blood vessels. In contrast, the immunoreactive material to anti-M antibody was associated to the sparse fragments of parenchymatous BMs and it delineated the boundary of adenoma cells and stroma. Within the stroma, the anti-M antibody immunoreactivity was regularly associated with the arterial walls but rarely with the venule walls. CONCLUSIONS: The human normal and tumoral anterior pituitary express all five LM subunits and thus contain several LM isoforms with different patterns of localization. The most striking difference between the human normal and tumoral anterior pituitary concerns the peculiar expression of LM isoforms by adenomatous neovessels.

Adenoma↗
PubMed1993

Comparison of computerized tomography and magnetic resonance imaging for the examination of the pituitary gland in patients with Cushing's disease.

OBJECTIVE: The vast majority of patients with Cushing's disease have a corticotroph adenoma, the selective removal of which, through the transsphenoidal route, has the potential to offer a definitive and complete cure. This study was designed to compare the diagnostic accuracy of computerized tomography (CT) and magnetic resonance imaging (MRI) to identify the presence, evaluate the size, and assess the topographic characteristics of pituitary corticotroph adenomas. METHODS: Forty-two patients with Cushing's disease were included in this prospective study, of whom 16 were subsequently explored transsphenoidally. Computerized tomography used a CE 12,000 CGR apparatus with 1.5-mm coronal slices and a 2-mm interslice gap. Magnetic resonance imaging used an MR Max 0.5T GE apparatus; adjacent 3-mm slices were obtained with a T1-weighted gradient echo before and after gadolinium injection. RESULTS: Lesions compatible with an adenoma were identified in 29 patients by MRI and in 21 patients by CT (69 vs 50%, P < 0.02). Seven macroadenomas were identified as well by the two methods. Eight of the 22 microadenomas detected by MRI were not identified by CT. Evidence for intracavernous tumour extension was found in nine patients: it was more frequently detected by MRI (8 patients) than by CT (4 patients). Fourteen patients with positive MRI had a pituitary examination: in one case the adenoma could not be reached because of purely suprasellar location; of the other 13 all were found by the surgeon and the surgical outcome was successful in 12 cases. CONCLUSION: MRI is superior to CT for the examination of the pituitary gland in patients with Cushing's disease.

Adolescent↗
PubMed1993

[Enlarged trans-temporal crania fossa approach. Technique and indications].

The authors report their experience using an enlarged middle cranial fossa approach for the removal of 33 acoustic neurinomas and 10 cerebellopontine angle meningiomas. The Technique is defined. This approach proved suitable for stage I neurinomas, ensuring total removal in all 13 patients with stage I lesions, hearing conservation in 9 (69.2%) of these patients, grade 1 + 2 facial nerve function in 80% of patients and grade 3 function in 20% of patients. While total removal was always possible for stage II neurinomas, the functional results were poor with hearing conservation in only 3 of 15 patients (20%), grade 1 + 2 facial nerve function in 45% of patients and grade 3 function in 54% of patients. Total removal was possible in only 1 of 4 patients with stage III neurinomas. This approach proved excellent for cerebellopontine anale meningiomas, providing wide access to the tumor and protecting the acoustico-facial bundle situated behind the tumor. Among the 10 patients operated by this route, 8 had conservation of hearing and all 10 had normal facial motricity (grade I) at 3 months.

Hearing Disorders↗
PubMed1992

Sphenocavernous and infratemporal trigeminal neurinomas: surgical series of 15 cases.

A consecutive series of 15 patients with trigeminal schwannomas treated surgically at the Centre Medico-Chirurgical Foch between 1979 and 1985 is reported. This report is limited to sphenocavernous (nine cases) and infratemporal (six cases) tumors. Initial clinical symptoms of these cases are detailed, including trigeminal and abducens nerve signs. Preoperative selective angiography and embolization are important adjuncts to surgical management. The surgical approach depends on the anatomic location of the tumor. Sphenocavernous neurinomas were removed through a pterionosubtemporal approach. Occasionally, infratemporal neurinomas were approached in two stages because of the need to reconstruct the skull base and prevent postoperative cerebrospinal fluid rhinorrhea. There were no operative deaths in the series and complete extirpation was achieved in all but one case.

Journal Article↗
PubMed1992

Thalamocortical diaschisis: positron emission tomography in humans.

To investigate further the relations between cortical energy metabolism and neuropsychological impairment after unilateral thalamic lesion, 55 patients underwent positron emission tomography studies of either cortical oxygen consumption or glucose utilisation, including eight repeat studies, at times ranging from 4 days to 98 months after the onset of the lesion [stroke (n = 44) or stereotaxic VL-Vim thalamotomy performed for movement disorders (n = 11)]. Patients with thalamotomy were also studied preoperatively and the surgery induced a significant fall in cortical metabolism on both sides (more so ipsilaterally); post-operatively the magnitude of the ipsilateral cortex hypometabolism was positively correlated to the severity of global neuropsychological impairment; similar but less significant findings were obtained for the ipsilateral/contralateral cortical metabolic asymmetry. With respect to the whole patient sample, the cortical metabolic asymmetry was initially pronounced, with subsequent monoexponential recovery, in the cognitively impaired study group, but it was only mild and showed no meaningful trend for recovery in the cognitively unaffected study group; yet even soon (< 3 months) after thalamic lesion there was a noticeable overlap of individual asymmetry values among the two study groups. These results lend further support to the view that the neuropsychological impairment that frequently follows unilateral thalamic lesions is reflected in a depression of synaptic activity in both the overlying and the contralateral cerebral cortices. For individual patients, this study also illustrates the potentially misleading nature of the measured cortical metabolic asymmetry with respect to neuropsychological status, especially at late times after lesion, in part because side to side metabolic ratios do not reflect bilateral changes.

Adult↗