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Empty sella in children as a key for diagnosis
Brain & Development 23 (2001) 422–423 www.elsevier.com/locate/braindev
Original article
Empty sella in children as a key for diagnosis Jun-ichi Takanashi a,*, Hiroko Suzuki a, Kasumi Nagasawa a, Kazuhiko Kobayashi a, Naokatsu Saeki b, Yoichi Kohno a b
a Department of Pediatrics, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8677, Japan Department of Neurosurgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8677, Japan
Received 22 May 2001; received in revised form 16 July 2001; accepted 18 July 2001
Abstract We performed magnetic resonance imaging of the pituitary gland in 354 children who were under the care of our pediatric neurological outpatient department. Among them, an empty sella was recognized in 11 children, who all showed normal hormonal results. The frequency of an empty sella was significantly high in idiopathic intracranial hypertension (4/4; P , 0:0001) and nevoid basal cell carcinoma syndrome (3/5; P , 0:0001). The ratio of an empty sella in children, excluding patients with idiopathic intracranial hypertension and nevoid basal cell carcinoma syndrome, is estimated to be 4/345 (1.2%), which is markedly lower than that in adults. Magnetic resonance imaging of the pituitary gland in children could provide important clues for the diagnosis of idiopathic intracranial hypertension or nevoid basal cell carcinoma syndrome. q 2001 Elsevier Science B.V. All rights reserved. Keywords: Empty sella; Idiopathic intracranial hypertension; Nevoid basal cell carcinoma syndrome
1. Introduction
2. Patients and methods
An empty sella (ES) is an anatomical condition comprising a sella turtica that is partially or completely filled with cerebrospinal fluid (CSF). In the majority of individuals, the diaphragm that overlies the sella only allows the passage of the pituitary stalk, preventing herniation of the subarachnoid space into the sella. However, protrusion of the subarachnoid space through the opening in the sellar diaphragm occurs in more than 20% of normal adults; in about 5%, more significant herniation is associated with ES [1]. In the pediatric age group, ES has been reported to be associated with hypothalamic pituitary disorders [1,2]. Due to the fact that only a select group of patients referred for possible endocrine dysfunction have been examined, the true incidence of ES in children is uncertain. The purposes of this study are to evaluate the prevalence rate of ES on magnetic resonance (MR) imaging in children without hypothalamic pituitary disorders, and to determine whether or not the presence of ES could allow some neurological diagnosis.
We retrospectively reviewed the T1 weighted sagittal images in 354 patients under 18 years of age (140 patients under 6 years of age, 135 patients aged between 7 and 12 years, and 79 patients aged between 13 and 18 years). They were taken care of at the pediatric neurological outpatient department of Chiba University Hospital between April 1994 and December 2000. None had an established diagnosis of a brain tumor or a hypothalamic pituitary disorder. The diagnosis or chief complaint was cerebral palsy or psychomotor retardation in 112 patients, epilepsy or syncope in 95 patients, cerebrovascular disease in 26 patients, headache in 18 patients, nevoid basal cell carcinoma syndrome (NBCCS) in five patients, and idiopathic intracranial hypertension (IIH) in four patients. The clinical and neuroradiological manifestations of the patients with NBCCS and IIH were reported elsewhere [3–5]. None of these patients exhibited any clinically endocrinological abnormalities, such as a short stature, or precocious or delayed puberty. MR imaging was performed with a 1.5-T superconducting magnet (Signa Horizon, General Electric, Milwaukee, WI). Sagittal T1 weighted images were evaluated for the pituitary gland. The parameters were as follows: matrix size, 256 £ 256; field of view, 25 cm; slice thickness, 6 mm for routine or 3 mm for precise evaluation of the pituitary gland;
* Corresponding author. Tel.: 181-43-226-2144; fax: 181-43-226-2145. E-mail address: [email protected] (J.- Takanashi).
0387-7604/01/$ - see front matter q 2001 Elsevier Science B.V. All rights reserved. PII: S03 87- 7604(01)0025 4-6
J.-i. Takanashi et al. / Brain & Development 23 (2001) 422–423
and slice gap, 1 mm. A diagnosis of ES was made when the pituitary gland occupied less than 50% of the sellar area and the top of the pituitary gland was concave on midsagittal T1 weighted imaging [6]. We used Fisher’s test for statistical analysis. For patients with an established diagnosis of ES, pituitary function was examined hormonally; including somatomedin-C, thyroid-stimulating hormone and thyroxine. 3. Results ES was recognized in 11 of the 354 patients. All four children with IIH and three of the five children with NBCCS had ES, respectively. Another four patients with ES were as follows: a 4-year-old male with epilepsy; a 4year-old male with myoclonus; a 7-year-old female with epilepsy; and a 7-year-old female with retinal degeneration. The endocrine pituitary function was examined for 11 ES patients, the results being within normal limits. Accordingly, the frequency of ES in children (other than those with IIH or NBCCS) was estimated to be 4/345 (1.2%). According to Fisher’s test, the frequency of ES was significantly high in IIH (P , 0:0001) and NBCCS (P , 0:0001).
423
increased CSF pressure and a papilloedema in patients without focal neurological findings, except for occasional sixth nerve palsy. Direct transmission of the elevated CSF pressure through the diaphragma sella in IIH can result in ES [8]. MR imaging disclosed an ES in 70% of 20 patients with IIH [6]. In the present study, all four patients with IIH showed ES — this frequency is significantly high. MR imaging focusing on the pituitary gland should be performed routinely in patients with headache in order not to miss IIH. In the present study, the prevalence of ES in NBCCS was also significantly high. In NBCCS, calcification of the sellar diaphragm (bridging of the sella turcica), which is a protective barrier against the pulsating action that the CSF exerts on the sellar contents, is seen in at least 60–80% of cases, a finding noted in only about 4% of the normal population [9]. It is considered that calcification of the sellar diaphragm in NBCCS may reduce the protection against CSF pulsation, and thereafter cause primary ES. Since the calcification is hardly recognizable on routine MR imaging, the presence of ES could provide a clue for the diagnosis of NBCCS. In conclusion, the ratio of ES in children is estimated to be 4/345 (1.2%), which is markedly lower than that in adults. The presence of ES in children could provide an important clue for the diagnosis of IIH and NBCCS.
4. Discussion References ES is a condition in which the sella turcica is partially or completely filled with CSF. Primary ES arises in the absence of previous pituitary surgery or irradiation, while secondary ES arises from a reduction of the intrasellar contents following pituitary surgery, radiation or infarction, which allows herniation of the subarachnoid space into the empty space. Factors possibly playing roles in primary ES are: insufficiency or absence of a sellar diaphragm and pituitary involution related to aging [7]. In general, a progressive increase in the incidence of the signs of primary ES on MR imaging has been observed with aging, namely in 9.6% of subjects under the age of 40 years and in 39.9% of those over 40 [7]. Primary ES in children is often associated with hypothalamic–pituitary dysfunction, the frequency being 10.9% (37/339) among patients with possible hypothalamic–pituitary disorders [2]. However, the prevalence of ES in normal children is unknown to the best of our knowledge. In this study, excluding patients with IIH and NBCCS, the frequency of ES in children is estimated to be 4/345 (1.2%), which is markedly lower than in adults. IIH, also known as pseudotumor cerebri and benign intracranial hypertension, is a syndrome characterized by
[1] Shulman DI, Martinez CR, Bercu BB, Root AW. Hypothalamic–pituitary dysfunction in primary empty sella syndrome in childhood. J Pediatr 1986;108:540–544. [2] Cacciari E, Zucchini S, Ambrosetto P, Tani G, Carla G, Cinognani A, et al. Empty sella in children and adolescents with possible hypothalamic–pituitary disorders. J Clin Endocrinol Metab 1994;78:767–771. [3] Suzuki H, Takanashi J, Kobayashi K, Nagasawa K, Tashima K, Kohno Y. MR imaging in idiopathic intracranial hypertension. Am J Neuroradiol 2001;22:196–199. [4] Takanashi J, Fujii K, Takano H, Sugita K, Kohno Y. Empty sella syndrome in nevoid basal cell carcinoma syndrome. Brain Dev 2000;22:272–274. [5] Suzuki H, Takanashi J, Nagasawa K, Kobayashi K, Tomita M, Tamai K, et al. Clinical and MRI findings in childhood idiopathic intracranial hypertension In Japanese. No to Hattatsu (Tokyo) 2001;33:319–322. [6] Brodsky MC, Valhiades M. Magnetic resonance imaging in pseudotumor cerebri. Ophthalmology 1998;105:1686–1693. [7] Foresti M, Guidali A, Susanna P. Primary empty sella. Incidence in 500 asymptomatic subjects examined with magnetic resonance. Radiol Med 1991;81:803–807. [8] Geoge AE. Idiopathic intracranial hypertension: pathogenesis and the role of MR imaging. Radiology 1989;170:21–22. [9] Kimonis VE, Goldstein AM, Pastakia B, Yang ML, Kase R, DiGiovanna JJ, et al. Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome. Am J Med Genet 1997;69:299–308.
Original article
Empty sella in children as a key for diagnosis Jun-ichi Takanashi a,*, Hiroko Suzuki a, Kasumi Nagasawa a, Kazuhiko Kobayashi a, Naokatsu Saeki b, Yoichi Kohno a b
a Department of Pediatrics, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8677, Japan Department of Neurosurgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba 260-8677, Japan
Received 22 May 2001; received in revised form 16 July 2001; accepted 18 July 2001
Abstract We performed magnetic resonance imaging of the pituitary gland in 354 children who were under the care of our pediatric neurological outpatient department. Among them, an empty sella was recognized in 11 children, who all showed normal hormonal results. The frequency of an empty sella was significantly high in idiopathic intracranial hypertension (4/4; P , 0:0001) and nevoid basal cell carcinoma syndrome (3/5; P , 0:0001). The ratio of an empty sella in children, excluding patients with idiopathic intracranial hypertension and nevoid basal cell carcinoma syndrome, is estimated to be 4/345 (1.2%), which is markedly lower than that in adults. Magnetic resonance imaging of the pituitary gland in children could provide important clues for the diagnosis of idiopathic intracranial hypertension or nevoid basal cell carcinoma syndrome. q 2001 Elsevier Science B.V. All rights reserved. Keywords: Empty sella; Idiopathic intracranial hypertension; Nevoid basal cell carcinoma syndrome
1. Introduction
2. Patients and methods
An empty sella (ES) is an anatomical condition comprising a sella turtica that is partially or completely filled with cerebrospinal fluid (CSF). In the majority of individuals, the diaphragm that overlies the sella only allows the passage of the pituitary stalk, preventing herniation of the subarachnoid space into the sella. However, protrusion of the subarachnoid space through the opening in the sellar diaphragm occurs in more than 20% of normal adults; in about 5%, more significant herniation is associated with ES [1]. In the pediatric age group, ES has been reported to be associated with hypothalamic pituitary disorders [1,2]. Due to the fact that only a select group of patients referred for possible endocrine dysfunction have been examined, the true incidence of ES in children is uncertain. The purposes of this study are to evaluate the prevalence rate of ES on magnetic resonance (MR) imaging in children without hypothalamic pituitary disorders, and to determine whether or not the presence of ES could allow some neurological diagnosis.
We retrospectively reviewed the T1 weighted sagittal images in 354 patients under 18 years of age (140 patients under 6 years of age, 135 patients aged between 7 and 12 years, and 79 patients aged between 13 and 18 years). They were taken care of at the pediatric neurological outpatient department of Chiba University Hospital between April 1994 and December 2000. None had an established diagnosis of a brain tumor or a hypothalamic pituitary disorder. The diagnosis or chief complaint was cerebral palsy or psychomotor retardation in 112 patients, epilepsy or syncope in 95 patients, cerebrovascular disease in 26 patients, headache in 18 patients, nevoid basal cell carcinoma syndrome (NBCCS) in five patients, and idiopathic intracranial hypertension (IIH) in four patients. The clinical and neuroradiological manifestations of the patients with NBCCS and IIH were reported elsewhere [3–5]. None of these patients exhibited any clinically endocrinological abnormalities, such as a short stature, or precocious or delayed puberty. MR imaging was performed with a 1.5-T superconducting magnet (Signa Horizon, General Electric, Milwaukee, WI). Sagittal T1 weighted images were evaluated for the pituitary gland. The parameters were as follows: matrix size, 256 £ 256; field of view, 25 cm; slice thickness, 6 mm for routine or 3 mm for precise evaluation of the pituitary gland;
* Corresponding author. Tel.: 181-43-226-2144; fax: 181-43-226-2145. E-mail address: [email protected] (J.- Takanashi).
0387-7604/01/$ - see front matter q 2001 Elsevier Science B.V. All rights reserved. PII: S03 87- 7604(01)0025 4-6
J.-i. Takanashi et al. / Brain & Development 23 (2001) 422–423
and slice gap, 1 mm. A diagnosis of ES was made when the pituitary gland occupied less than 50% of the sellar area and the top of the pituitary gland was concave on midsagittal T1 weighted imaging [6]. We used Fisher’s test for statistical analysis. For patients with an established diagnosis of ES, pituitary function was examined hormonally; including somatomedin-C, thyroid-stimulating hormone and thyroxine. 3. Results ES was recognized in 11 of the 354 patients. All four children with IIH and three of the five children with NBCCS had ES, respectively. Another four patients with ES were as follows: a 4-year-old male with epilepsy; a 4year-old male with myoclonus; a 7-year-old female with epilepsy; and a 7-year-old female with retinal degeneration. The endocrine pituitary function was examined for 11 ES patients, the results being within normal limits. Accordingly, the frequency of ES in children (other than those with IIH or NBCCS) was estimated to be 4/345 (1.2%). According to Fisher’s test, the frequency of ES was significantly high in IIH (P , 0:0001) and NBCCS (P , 0:0001).
423
increased CSF pressure and a papilloedema in patients without focal neurological findings, except for occasional sixth nerve palsy. Direct transmission of the elevated CSF pressure through the diaphragma sella in IIH can result in ES [8]. MR imaging disclosed an ES in 70% of 20 patients with IIH [6]. In the present study, all four patients with IIH showed ES — this frequency is significantly high. MR imaging focusing on the pituitary gland should be performed routinely in patients with headache in order not to miss IIH. In the present study, the prevalence of ES in NBCCS was also significantly high. In NBCCS, calcification of the sellar diaphragm (bridging of the sella turcica), which is a protective barrier against the pulsating action that the CSF exerts on the sellar contents, is seen in at least 60–80% of cases, a finding noted in only about 4% of the normal population [9]. It is considered that calcification of the sellar diaphragm in NBCCS may reduce the protection against CSF pulsation, and thereafter cause primary ES. Since the calcification is hardly recognizable on routine MR imaging, the presence of ES could provide a clue for the diagnosis of NBCCS. In conclusion, the ratio of ES in children is estimated to be 4/345 (1.2%), which is markedly lower than that in adults. The presence of ES in children could provide an important clue for the diagnosis of IIH and NBCCS.
4. Discussion References ES is a condition in which the sella turcica is partially or completely filled with CSF. Primary ES arises in the absence of previous pituitary surgery or irradiation, while secondary ES arises from a reduction of the intrasellar contents following pituitary surgery, radiation or infarction, which allows herniation of the subarachnoid space into the empty space. Factors possibly playing roles in primary ES are: insufficiency or absence of a sellar diaphragm and pituitary involution related to aging [7]. In general, a progressive increase in the incidence of the signs of primary ES on MR imaging has been observed with aging, namely in 9.6% of subjects under the age of 40 years and in 39.9% of those over 40 [7]. Primary ES in children is often associated with hypothalamic–pituitary dysfunction, the frequency being 10.9% (37/339) among patients with possible hypothalamic–pituitary disorders [2]. However, the prevalence of ES in normal children is unknown to the best of our knowledge. In this study, excluding patients with IIH and NBCCS, the frequency of ES in children is estimated to be 4/345 (1.2%), which is markedly lower than in adults. IIH, also known as pseudotumor cerebri and benign intracranial hypertension, is a syndrome characterized by
[1] Shulman DI, Martinez CR, Bercu BB, Root AW. Hypothalamic–pituitary dysfunction in primary empty sella syndrome in childhood. J Pediatr 1986;108:540–544. [2] Cacciari E, Zucchini S, Ambrosetto P, Tani G, Carla G, Cinognani A, et al. Empty sella in children and adolescents with possible hypothalamic–pituitary disorders. J Clin Endocrinol Metab 1994;78:767–771. [3] Suzuki H, Takanashi J, Kobayashi K, Nagasawa K, Tashima K, Kohno Y. MR imaging in idiopathic intracranial hypertension. Am J Neuroradiol 2001;22:196–199. [4] Takanashi J, Fujii K, Takano H, Sugita K, Kohno Y. Empty sella syndrome in nevoid basal cell carcinoma syndrome. Brain Dev 2000;22:272–274. [5] Suzuki H, Takanashi J, Nagasawa K, Kobayashi K, Tomita M, Tamai K, et al. Clinical and MRI findings in childhood idiopathic intracranial hypertension In Japanese. No to Hattatsu (Tokyo) 2001;33:319–322. [6] Brodsky MC, Valhiades M. Magnetic resonance imaging in pseudotumor cerebri. Ophthalmology 1998;105:1686–1693. [7] Foresti M, Guidali A, Susanna P. Primary empty sella. Incidence in 500 asymptomatic subjects examined with magnetic resonance. Radiol Med 1991;81:803–807. [8] Geoge AE. Idiopathic intracranial hypertension: pathogenesis and the role of MR imaging. Radiology 1989;170:21–22. [9] Kimonis VE, Goldstein AM, Pastakia B, Yang ML, Kase R, DiGiovanna JJ, et al. Clinical manifestations in 105 persons with nevoid basal cell carcinoma syndrome. Am J Med Genet 1997;69:299–308.