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Ingrid E Scheffer - One of the best experts on this subject based on the ideXlab platform.
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Ectopic Posterior Pituitary Lobe and Periventricular Heterotopia: Cerebral Malformations with the Same Underlying Mechanism?
2015Co-Authors: Anne L Mitchell, Paul Q. Thomas, Margaret Zacharin, Ingrid E SchefferAbstract:with growth hormone deficiency and is part of the spectrum associated with septo-optic dysplasia. Some cases of septo-optic dysplasia are caused by homozygous mutations in the homeobox gene HESX1, whereas heterozygous mutations are associated with milder pheno-types. To date, HESX1 is the only gene associated with ectopic Posterior Pituitary lobe. We describe an association between ectopic Posterior Pituitary lobe and periventricular heterotopia in four children without classic features of septo-optic dysplasia and suggest possible mecha-nisms on the basis of a review of Pituitary embryology and recent molecular genetic advances. METHODS: Among 20 children with ectopic Posterior Pituitary lobe, four had associated periventricular heterotopia. We herein review the clinical and MR imaging findings of these four children. Mutation screening of HESX1 was performed in two. RESULTS: All four children had growth hormone deficiency. None had visual or neurologic disturbances. MR images showed a range of Pituitary appearances, with scattered discrete periventricular heterotopia in each case. Other abnormalities were limited to small suprasellar lipomas and callosal dysgenesis. A heterozygous HESX1 mutation was present in one case. CONCLUSION: The coexistence of ectopic Posterior Pituitary lobe and periventricular hete
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ectopic Posterior Pituitary lobe and periventricular heterotopia cerebral malformations with the same underlying mechanism
American Journal of Neuroradiology, 2002Co-Authors: Anne L Mitchell, Paul Q. Thomas, Margaret Zacharin, Ingrid E SchefferAbstract:BACKGROUND AND PURPOSE: Ectopic Posterior Pituitary lobe often occurs in children with growth hormone deficiency and is part of the spectrum associated with septo-optic dysplasia. Some cases of septo-optic dysplasia are caused by homozygous mutations in the homeobox gene HESX1, whereas heterozygous mutations are associated with milder phenotypes. To date, HESX1 is the only gene associated with ectopic Posterior Pituitary lobe. We describe an association between ectopic Posterior Pituitary lobe and periventricular heterotopia in four children without classic features of septo-optic dysplasia and suggest possible mechanisms on the basis of a review of Pituitary embryology and recent molecular genetic advances. METHODS: Among 20 children with ectopic Posterior Pituitary lobe, four had associated periventricular heterotopia. We herein review the clinical and MR imaging findings of these four children. Mutation screening of HESX1 was performed in two. RESULTS: All four children had growth hormone deficiency. None had visual or neurologic disturbances. MR images showed a range of Pituitary appearances, with scattered discrete periventricular heterotopia in each case. Other abnormalities were limited to small suprasellar lipomas and callosal dysgenesis. A heterozygous HESX1 mutation was present in one case. CONCLUSION: The coexistence of ectopic Posterior Pituitary lobe and periventricular heterotopia suggests they have a common underlying genetic basis that is due to gene expression at different locations and stages of development. The presence of a heterozygous HESX1 mutation in one case suggests this gene is important in the development of both ectopic Posterior Pituitary lobe and periventricular heterotopia and supports their place in the spectrum of septo-optic dysplasia. Further analysis of HESX1 and other genes in related developmental pathways will elucidate their roles in the development of both malformations.
Christopher J Thompson - One of the best experts on this subject based on the ideXlab platform.
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Posterior Pituitary dysfunction after traumatic brain injury
The Journal of Clinical Endocrinology and Metabolism, 2004Co-Authors: Amar Agha, Evan Thornton, Patrick Okelly, William Tormey, J Phillips, Christopher J ThompsonAbstract:Disorders of water balance are well recognized after traumatic brain injury (TBI), but there are no reliable data on their true prevalence in post-TBI patients. We aimed to evaluate the prevalence of Posterior Pituitary dysfunction in a large cohort of survivors of TBI. One hundred two consecutive patients (85 males) who suffered severe or moderate TBI were evaluated for diabetes insipidus (DI) at a median of 17 months (range 6–36 months) after the event, using the 8-h water deprivation test (WDT). Their results were compared against normative data obtained from 27 matched, healthy controls. Patients’ medical records were retrospectively reviewed for the presence of abnormalities of salt and water balance in the immediate post-TBI period. Twenty-two patients (21.6%) developed DI in the immediate post-TBI period (acute DI group), of whom five had abnormal WDT on later testing. In total, seven patients (6.9%) had abnormal WDT (permanent DI group), five of whom had partial DI. Patients in the acute and perma...
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Posterior Pituitary dysfunction after traumatic brain injury
The Journal of Clinical Endocrinology and Metabolism, 2004Co-Authors: Amar Agha, Evan Thornton, Patrick Okelly, William Tormey, John P Phillips, Christopher J ThompsonAbstract:Disorders of water balance are well recognized after traumatic brain injury (TBI), but there are no reliable data on their true prevalence in post-TBI patients. We aimed to evaluate the prevalence of Posterior Pituitary dysfunction in a large cohort of survivors of TBI. One hundred two consecutive patients (85 males) who suffered severe or moderate TBI were evaluated for diabetes insipidus (DI) at a median of 17 months (range 6-36 months) after the event, using the 8-h water deprivation test (WDT). Their results were compared against normative data obtained from 27 matched, healthy controls. Patients' medical records were retrospectively reviewed for the presence of abnormalities of salt and water balance in the immediate post-TBI period. Twenty-two patients (21.6%) developed DI in the immediate post-TBI period (acute DI group), of whom five had abnormal WDT on later testing. In total, seven patients (6.9%) had abnormal WDT (permanent DI group), five of whom had partial DI. Patients in the acute and permanent DI groups were more likely to have more severe TBI, compared with the rest of the cohort (P < 0.05). In the immediate post-TBI period, 13 patients (12.9%) had syndrome of inappropriate secretion of antidiuretic hormone, which persisted in one patient, and one other patient developed cerebral salt wasting. Diabetes insipidus and syndrome of inappropriate secretion of antidiuretic hormone were common in the immediate post-TBI period. Permanent DI was present in 6.9% of patients who survived severe or moderate TBI, which is higher than traditionally thought. Identification of patients with partial posttraumatic DI is important because appropriate treatment may reduce morbidity and optimize the potential for recovery.
Anne L Mitchell - One of the best experts on this subject based on the ideXlab platform.
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Ectopic Posterior Pituitary Lobe and Periventricular Heterotopia: Cerebral Malformations with the Same Underlying Mechanism?
2015Co-Authors: Anne L Mitchell, Paul Q. Thomas, Margaret Zacharin, Ingrid E SchefferAbstract:with growth hormone deficiency and is part of the spectrum associated with septo-optic dysplasia. Some cases of septo-optic dysplasia are caused by homozygous mutations in the homeobox gene HESX1, whereas heterozygous mutations are associated with milder pheno-types. To date, HESX1 is the only gene associated with ectopic Posterior Pituitary lobe. We describe an association between ectopic Posterior Pituitary lobe and periventricular heterotopia in four children without classic features of septo-optic dysplasia and suggest possible mecha-nisms on the basis of a review of Pituitary embryology and recent molecular genetic advances. METHODS: Among 20 children with ectopic Posterior Pituitary lobe, four had associated periventricular heterotopia. We herein review the clinical and MR imaging findings of these four children. Mutation screening of HESX1 was performed in two. RESULTS: All four children had growth hormone deficiency. None had visual or neurologic disturbances. MR images showed a range of Pituitary appearances, with scattered discrete periventricular heterotopia in each case. Other abnormalities were limited to small suprasellar lipomas and callosal dysgenesis. A heterozygous HESX1 mutation was present in one case. CONCLUSION: The coexistence of ectopic Posterior Pituitary lobe and periventricular hete
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ectopic Posterior Pituitary lobe and periventricular heterotopia cerebral malformations with the same underlying mechanism
American Journal of Neuroradiology, 2002Co-Authors: Anne L Mitchell, Paul Q. Thomas, Margaret Zacharin, Ingrid E SchefferAbstract:BACKGROUND AND PURPOSE: Ectopic Posterior Pituitary lobe often occurs in children with growth hormone deficiency and is part of the spectrum associated with septo-optic dysplasia. Some cases of septo-optic dysplasia are caused by homozygous mutations in the homeobox gene HESX1, whereas heterozygous mutations are associated with milder phenotypes. To date, HESX1 is the only gene associated with ectopic Posterior Pituitary lobe. We describe an association between ectopic Posterior Pituitary lobe and periventricular heterotopia in four children without classic features of septo-optic dysplasia and suggest possible mechanisms on the basis of a review of Pituitary embryology and recent molecular genetic advances. METHODS: Among 20 children with ectopic Posterior Pituitary lobe, four had associated periventricular heterotopia. We herein review the clinical and MR imaging findings of these four children. Mutation screening of HESX1 was performed in two. RESULTS: All four children had growth hormone deficiency. None had visual or neurologic disturbances. MR images showed a range of Pituitary appearances, with scattered discrete periventricular heterotopia in each case. Other abnormalities were limited to small suprasellar lipomas and callosal dysgenesis. A heterozygous HESX1 mutation was present in one case. CONCLUSION: The coexistence of ectopic Posterior Pituitary lobe and periventricular heterotopia suggests they have a common underlying genetic basis that is due to gene expression at different locations and stages of development. The presence of a heterozygous HESX1 mutation in one case suggests this gene is important in the development of both ectopic Posterior Pituitary lobe and periventricular heterotopia and supports their place in the spectrum of septo-optic dysplasia. Further analysis of HESX1 and other genes in related developmental pathways will elucidate their roles in the development of both malformations.
Mohamad Maghnie - One of the best experts on this subject based on the ideXlab platform.
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novel hesx1 mutations associated with a life threatening neonatal phenotype Pituitary aplasia but normally located Posterior Pituitary and no optic nerve abnormalities
The Journal of Clinical Endocrinology and Metabolism, 2006Co-Authors: Marie Laure Sobrie, Mohamad Maghnie, Marie Pierre Vieluto, Andrea Secco, Natascia Di Iorgi, R Lorini, Serge AmselemAbstract:Objective:The objectives of the study were to describe the complex phenotype associated with the panhypopituitarism of two unrelated Italian patients who, at birth, presented with hypoglycemic seizures and respiratory distress complicated by shock, in a familial context of neonatal death in one family and spontaneous miscarriage in both families and to identify the molecular basis of this unusual syndrome. Main Outcome Measures: Magnetic resonance imaging of the Pituitary region, study of HESX1 gene and transcripts, and assessment of the ability of mutated HESX1 proteins to repress transcription were measured. Results: Magnetic resonance imaging examination showed an anterior Pituitary aplasia in a flat sella turcica and a normally located Posterior Pituitary in both patients. A constellation of extraPituitary developmentaldefectswerefoundinthetwopatients,butwithoutany optic nerve abnormalities. Sequencing of HESX1 exons and their flanking intronic regions revealed two different homozygous mutations. A frameshift (c.449_450delAC) was identified in one case, whereas the other patient carried a splice defect (c.357 2TC) confirmed by the study of HESX1 transcripts. If translated, these mutations would lead to the synthesis of truncated proteins partly or entirely lacking the homeodomain, with no transcriptional repression, as shown by their inability to inhibit PROP1 activity. Conclusions: These observations reveal two novel HESX1 mutations in a so-far-undescribed disease phenotype characterized by a life-threatening neonatal condition associated with anterior Pituitary aplasia, in the absence of ectopic Posterior Pituitary and optic nerve abnormalities, two features classically associated with HESX1 defects. (J Clin Endocrinol Metab 91: 4528–4536, 2006)
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idiopathic central diabetes insipidus is associated with abnormal blood supply to the Posterior Pituitary gland caused by vascular impairment of the inferior hypophyseal artery system
The Journal of Clinical Endocrinology and Metabolism, 2004Co-Authors: Mohamad Maghnie, Natascia Di Iorgi, Eugenio Annibale Genovese, Monica Altobelli, Giulia Meloni, Maria Luisa Mancabitti, Amnon Cohen, S BernasconiAbstract:Central diabetes insipidus (CDI) has been linked to vascular central nervous system damage, although the pathophysiology of the mechanism has never been perfectly understood. Indeed, the vascular system of human Pituitary gland has rarely been the subject of rigorous investigation except at postmortem. Recently, studies of Pituitary gland blood supply have been carried out by means of a time evaluation of Pituitary gland enhancement with noninvasive dynamic magnetic resonance (MR) imaging after contrast medium injection. In the present study, we decided to investigate the status of Posterior Pituitary blood supply by evaluating vascular Pituitary patterns in a group of 19 patients with idiopathic CDI in whom previous standard MR imaging had failed to identify causal specific lesions. The control group was composed of 55 subjects with a median age of 12 yr (range, 4.2-17 yr) who had idiopathic isolated GH deficiency and normal Pituitary morphology and 15 young adults (18-25 yr) who had normal Pituitary gland and no endocrine dysfunction. Nineteen patients (12 females and seven males), ranging in age at the time of diagnosis of CDI from 0.5-14.9 yr (median, 5 yr), were examined with dynamic MR imaging between 1990 and 1997 at a median age of 14.1 yr (range, 5.0-26.3 yr). CDI was diagnosed according to clinical findings of polyuria and polydipsia, water deprivation test, and desmopressin acetate therapeutic trial. All of the patients had permanent CDI and were being treated with satisfactory results with desmopressin, two to three times daily, either intranasally or orally. The previous MR imaging findings of the 19 CDI patients had shown the absence of Posterior Pituitary hyperintensity, normal Pituitary stalk, and normal anterior Pituitary size. Enhancement of the straight sinus, representing a temporal reference point and occurring in normal subjects simultaneously to that of the Posterior Pituitary gland, was observed in all subjects after iv gadopentetate dimeglumine administration, with no substantial differences between patients and controls. However, the enhancement of the Posterior Pituitary lobe occurred simultaneously with the enhancement of the straight sinus in all of the controls but in only 14 of the 19 patients with CDI. In the remaining five patients, the enhancement of the straight sinus was not associated with the expected contrast enhancement of the Posterior Pituitary gland, suggesting abnormal blood supply to the Posterior Pituitary lobe. This is in keeping with vascular impairment of the inferior hypophyseal artery system and suggests that abnormal blood supply to the Posterior Pituitary gland is associated with what, until now, has been considered idiopathic CDI.
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persistent high mr signal of the Posterior Pituitary gland in central diabetes insipidus
American Journal of Neuroradiology, 1997Co-Authors: Mohamad Maghnie, Eugenio Annibale Genovese, S Bernasconi, Silvana Binda, M. AricoAbstract:We describe three cases of central diabetes insipidus, each with a different pathogenesis, in which unexpected hyperintensity of the Posterior Pituitary gland was seen on T1-weighted MR images obtained at the time of presentation. In the first case (idiopathic), the Posterior Pituitary signal persisted more than 10 years; in the second case (Langerhans cell histiocytosis), the signal disappeared within 3 months, despite early specific chemotherapy with etoposide; and in the third case (transient), the Posterior signal disappeared within 1 year, but it was documented at the time of spontaneous reversal of polyuria and polydipsia.
Amar Agha - One of the best experts on this subject based on the ideXlab platform.
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Posterior Pituitary dysfunction after traumatic brain injury
The Journal of Clinical Endocrinology and Metabolism, 2004Co-Authors: Amar Agha, Evan Thornton, Patrick Okelly, William Tormey, J Phillips, Christopher J ThompsonAbstract:Disorders of water balance are well recognized after traumatic brain injury (TBI), but there are no reliable data on their true prevalence in post-TBI patients. We aimed to evaluate the prevalence of Posterior Pituitary dysfunction in a large cohort of survivors of TBI. One hundred two consecutive patients (85 males) who suffered severe or moderate TBI were evaluated for diabetes insipidus (DI) at a median of 17 months (range 6–36 months) after the event, using the 8-h water deprivation test (WDT). Their results were compared against normative data obtained from 27 matched, healthy controls. Patients’ medical records were retrospectively reviewed for the presence of abnormalities of salt and water balance in the immediate post-TBI period. Twenty-two patients (21.6%) developed DI in the immediate post-TBI period (acute DI group), of whom five had abnormal WDT on later testing. In total, seven patients (6.9%) had abnormal WDT (permanent DI group), five of whom had partial DI. Patients in the acute and perma...
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Posterior Pituitary dysfunction after traumatic brain injury
The Journal of Clinical Endocrinology and Metabolism, 2004Co-Authors: Amar Agha, Evan Thornton, Patrick Okelly, William Tormey, John P Phillips, Christopher J ThompsonAbstract:Disorders of water balance are well recognized after traumatic brain injury (TBI), but there are no reliable data on their true prevalence in post-TBI patients. We aimed to evaluate the prevalence of Posterior Pituitary dysfunction in a large cohort of survivors of TBI. One hundred two consecutive patients (85 males) who suffered severe or moderate TBI were evaluated for diabetes insipidus (DI) at a median of 17 months (range 6-36 months) after the event, using the 8-h water deprivation test (WDT). Their results were compared against normative data obtained from 27 matched, healthy controls. Patients' medical records were retrospectively reviewed for the presence of abnormalities of salt and water balance in the immediate post-TBI period. Twenty-two patients (21.6%) developed DI in the immediate post-TBI period (acute DI group), of whom five had abnormal WDT on later testing. In total, seven patients (6.9%) had abnormal WDT (permanent DI group), five of whom had partial DI. Patients in the acute and permanent DI groups were more likely to have more severe TBI, compared with the rest of the cohort (P < 0.05). In the immediate post-TBI period, 13 patients (12.9%) had syndrome of inappropriate secretion of antidiuretic hormone, which persisted in one patient, and one other patient developed cerebral salt wasting. Diabetes insipidus and syndrome of inappropriate secretion of antidiuretic hormone were common in the immediate post-TBI period. Permanent DI was present in 6.9% of patients who survived severe or moderate TBI, which is higher than traditionally thought. Identification of patients with partial posttraumatic DI is important because appropriate treatment may reduce morbidity and optimize the potential for recovery.
