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British Journal of Radiology 74 (2001),24-31 © 2001 The British Institute of Radiology

Full paper

MRI and clinical differences between optic pathway tumours in children with and without neurofibromatosis

J-F Chateil, MD, PhD1, C Soussotte, MD1, J-M Pédespan, MD2, M Brun, MD1, C Le Manh, MD1 and F Diard, MD1

1 Service de Radiologie A
2 Pédiatrie, Hôpital Pellegrin, Place A Raba Léon, 33076 Bordeaux, Cedex, France


   Abstract
Top
 Abstract
Introduction
 Material and methods
 Results
 Discussion
 References
 
The purpose of this study was to evaluate the value of MRI in studying optic pathway tumours associated with neurofibromatosis, and to look for potentially helpful criteria for the management of such lesions. This retrospective study included 14 children with neurofibromatosis type 1 (NF-1) as well as a lesion of the optic pathway. Clinical data and MRI findings were analysed with regard to location, structure and course of the tumours, and were compared with 13 optic pathway tumours in patients without NF-1. The median age of onset was 4.1 years. 11 patients with NF-1 were asymptomatic. In the NF-1 group, the optic nerves were involved in 10 cases without a cystic component at the time of diagnosis. In the non-NF-1 group, the tumour was located in the chiasma in 11 cases; 12 cases had a cystic component. 10 of the NF-1 group had no tumour progression over an average follow-up of 3.2 years without treatment. These findings suggest that optic astrocytomas in association with NF-1 are distinct lesions from isolated optic gliomas. In NF-1, most such tumours show only slight progression, and may correspond to perineural gliomatosis rather than a true pilocytic astrocytoma. Among NF-1 patients, initial MRI provides no prognostic criteria in children who subsequently show tumour progression. Nevertheless, MRI can be useful in establishing the diagnosis of NF-1 and can serve as a baseline study.


   Introduction
Top
 Abstract
 Introduction
Material and methods
 Results
 Discussion
 References
 
The relationship between optic nerve tumours and neurofibromatosis type 1 (NF-1) is well established. However, several questions remain unanswered regarding the natural history of these lesions: are the optic nerve gliomas observed in NF-1 true benign neoplasms or hamartomas? Are there differences in location and overall prognosis between lesions that occur in association with NF-1 and isolated tumours? MRI is the best means of imaging the optic pathways and is frequently performed in the initial screening of children with NF-1. To evaluate the contribution of MRI in distinguishing such lesions, we retrospectively reviewed the clinical data, MRI patterns and follow-up of children who had optic pathway tumour in the presence of NF-1. Imaging studies were compared with another group of patients without NF-1. The potential value of imaging criteria in the clinical, follow-up and therapeutic management of patients with NF-1 was analysed.


   Material and methods
Top
 Abstract
 Introduction
 Material and methods
Results
 Discussion
 References
 
Clinical charts and imaging studies of 14 children who had NF-1 and in whom a tumour of the optic pathways was discovered between 1986 and 1997 were retrospectively studied. Diagnosis of NF-1 was made according to the diagnostic criteria established by the National Institutes of Health Consensus Development Conference [1]. Visual evoked potentials were performed in nine of the children.

Imaging data were analysed in another group of 13 children with no stigmata of NF-1 on physical examination and no family history of NF-1 but who were evaluated during the same period with imaging for an optic pathway tumour.

Imaging studies
T1 weighted, proton density and T2 weighted MR images were obtained in all patients. Axial, coronal and sagittal images were studied. T1 weighted images were repeated after intravenous infusion of DTPA- or DOTA-gadolinium (0.1 mmol kg-1). Fat saturated contrast enhanced T1 weighted images were used in a few patients. The examination was conducted after sedation in children under the age of 4 years.

Imaging diagnostic criteria of an optic pathway lesion were a size or signal abnormality, or both, along the optic pathways. In cases with subtle changes in size, an abnormality was considered to be present when there was asymmetry between the two sides. The site of origin of the tumour may be difficult to determine in large suprasellar masses: the chiasma was considered to be primarily involved when it was not visible as a normal structure at the anterior margin of the tumour on sagittal and axial images.

The images were evaluated independently by two radiologists. Results were achieved by consensus when they did not fully agree. The following data were recorded: (i) location of the tumour at the time of initial diagnosis: lesion of the optic nerve (single or bilateral), in its intraorbital portion or its intracranial portion, lesion of the chiasma alone, or with forward extension into the optic nerves, involvement of thechiasma and the retrochiasmal optic pathways; (ii) maximum diameter of the tumour on axial slices; (iii) structure of the mass, especially whether or not there was a cystic component; (iv)presence and type of enhancement after gadolinium infusion; and (v) presence of other abnormalities: ventricular dilatation, abnormal parenchymal hyperintense signal on T2 weighted images, or other tumours.

Follow-up imaging studies were obtained for every child and the same parameters were assessed. The mean time of follow-up for the children with NF-1 was 3.5 years. Increases in tumour volume, modifications in enhancement and spreading of lesions along the optical tract were also studied at follow-up.

Data analysis
To determine whether there were significant differences between patients with NF-1 vs those without NF-1, continuous variables were analysed using Student's t-test, and frequency data were compared using {chi}2 analyses.


   Results
Top
 Abstract
 Introduction
 Material and methods
 Results
Discussion
 References
 
Subject age and sex
The age of onset was considered to be the age at which the lesion was discovered. Optic pathway lesions were found in seven girls and seven boys with NF-1, ranging in age from 1.5 years to 10 years (mean age 5.1 years, median age 4.2 years). The group of 13 children (8 girls and 5 boys) who did not have NF-1 ranged in age from 0.5 years to 14 years (mean age 4.3 years, median age 4.1 years).

Initial symptoms
Clinical signs are summarized in Table 1Go. These signs at the time of diagnosis are not comparable between the two groups, because in the group with NF-1 most children were explored because of this initial disease: 11 of the subjects with NF-1 did not have specific neurological symptoms and were identified by neuroimaging study at the time of diagnosis of NF-1. The other three presented with symptoms (see Table 1Go). Ophthalmological examination showed Lisch nodules in only one child. Family history of NF-1 was found in five cases. Two of the children in the NF-1 group had facial features of Noonan syndrome, including hypertelorism, proptosis, micrognathia and ear abnormalities. Visual evoked potentials were abnormal in all cases, with prolonged latencies.


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  		Table 1. Initial symptoms and signs

 
The optic pathway lesions were symptomatic in all children who did not have NF-1.

Imaging
Imaging results are presented in Table 2Go (tumour localization) and Table 3Go (other characteristics).


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  		Table 2. Tumour localization at time of diagnosis

 

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  		Table 3. MRI findings at time of diagnosis

 
NF-1 group
Isolated involvement of the optic nerves was exclusively found in the NF-1 group, affecting seven children, in two of whom the lesions were bilateral (Figure 1Go). Neither portion of the optic nerve (intraorbital or intracranial) was significantly more involved than the other. Two patients had isolated involvement of the chiasma. Two children had lesions of the chiasma and both optic nerves in their intracranial portion, and one had lesions of the chiasma and the intraorbital portion of the optic nerve. Two involvements of the chiasma and the retrochiasmal optic pathways were noted.



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  		Figure 1. 3-year-old boy with neurofibromatosis type 1. Axial T1 weighted image demonstrates a lesion of the left optic nerve, slight dilatation of the subarachnoid space surrounding the origin of the right optic nerve, and asymmetry in diameter between the intracranial portion of the right and the left optic nerves.

 
The longest axis of tumours in the chiasma varied from 10 mm to 20 mm (average 15.8 mm). In the optic nerves, tumours measured between 5 mm and 10 mm in the longest axis (average 8.9 mm). None of the tumours had a cystic component at diagnosis. Tumours were of homogeneous structure, isointense on T1 weighted sequences compared with the cerebral parenchyma, and isointense or slightly hyperintense on T2 weighted sequences. They were characterized by a tubular, tortuous widening of the nerve or a fusiform mass developed along the nerve. In the chiasma, the tumours took the form of a homogeneous nodular mass.

The tumour was enhanced by gadolinium in 4 of the 14 children. In two cases at diagnosis, enhancement was moderate and heterogeneous (Figure 2Go), and in the other two it was intense and homogeneous.



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  		Figure 2. 7-year-old boy with neurofibromatosis type 1. Axial T1 weighted image after contrast infusion. Enlargement of the intracranial portion of the left optic nerve, moderately enhanced by contrast.

 
A dysplastic buphtalmia was present in one case. Ventricular dilatation occurred in only one case, concomitant with growth of the tumour. There were intraparenchymal hyperintense signals on T2 weighted images in 12 of the children who had NF-1. Such hyperintensities were focal or multiple, exhibited no mass effect, and were generally unenhanced by gadolinium. Nine of the children with NF-1 had this finding in the globus pallidum, five in the internal capsule, seven in the cerebral peduncles and protuberance, and seven in the cerebellum. Several sites were involved in some children. These lesions were enhanced by contrast medium in two cases. Other anomalies in the NF-1 group included four cerebral tumours, three of which were supratentorial (in the thalamus, frontal cortex or tectum) and one of which involved the cerebellar vermis, three arachnoid cysts (two temporal but without sphenoid wing dysplasia, and one frontal), and one dysplastic widening of the internal auditory canals.

Non-NF-1 group
The chiasma was regularly involved (11 cases). One child presented with a lesion involving the entire right optic nerve with extension into the chiasma. Another child had involvement of the chiasma and of the retrochiasmal optic pathways. In the longest axis, the minimum tumour size was 16 mm and the maximum was 80 mm (average 42.4 mm). In this group, the tumour was typically nodular in form, well defined and contained both solid and cystic components (Figure 3Go). A cystic component was found in 7 of the 13 children at diagnosis. No intratumoral calcification or surrounding oedema was noted. Tumour enhancement was intense and homogeneous in the solid portions of the tumour in 10 of these 13 children.



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  		Figure 3. 3-year-old boy without neurofibromatosis type 1. Sagittal T1 weighted image after contrast infusion. Large tumour of the chiasma, with a cystic component and a solid portion, strongly enhanced by contrast medium. Medial herniation of the posterior part of the right dilated lateral ventrical, with compression of the aqueduct of Sylvius.

 
Ventricular dilation was present in five cases and related to tumoral obstruction of CSF flow in the third ventricle or aqueduct of Sylvius. Two children showed nodular meningeal enhancement after contrast medium, considered to be owing to metastasis.

Comparison of NF-1 and non-NF-1 groups
There were two characteristics regarding tumour location. In the NF-1 group, the optic nerves were involved more frequently than the chiasma or retrochiasmal pathways, with unilateral optic nerve involvement being most characteristic. In the non-NF-1 group, the tumour was most often located in the chiasma and no isolated optic nerve involvement was noted. There was a statistically significant difference in size between the two groups (p=0.01). Tumours occurring in patients who did not have NF-1 were approximately twice as long as tumours in NF-1 patients. Contrast enhancement and a cystic component were more frequent in the non-NF-1 group.

Treatment and outcome
In the NF-1 group, the optic pathway tumour was treated in two of the children by radiation therapy and in a third by chemotherapy. Only one biopsy was obtained, demonstrating a grade I astrocytoma. No therapy was initially given for the 11 remaining children. They were monitored by clinical examination and MRI once every 6 or 12 months. Changes were seen in five children. In one child, enhancement was first noted during a follow-up examination at 4 years; at that time, a hyperintense signal on T2 weighted images had developed in the optic tract, even though the volume of the tumour in the chiasma remained unchanged. In three cases, the tumour increased in volume (Figure 4Go) and hyperintensity developed on T2 weighted images. In a fifth patient, clinical signs of raised intracranial pressure permitted the diagnosis of a second tumour in the optic pathways (Figure 5Go). In this last case, imaging aspects were similar to those observed in the non-NF-1 group, with enhancement by contrast medium. Three deaths occurred in this group, in one case owing to rapid progression of the optic pathway tumour (Figure 5Go). The second death was caused by a thoracoabdominal neurofibrosarcoma and the third by a grade III astrocytoma of the frontal lobe.



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  		Figure 4. 3.5-year-old girl with neurofibromatosis type 1. (a) Coronal T1 weighted image shows enlargement of the right portion of the chiasma. (b) 4 years later, coronal T1 weighted image demonstrates progression in the size of the lesion. The patient remains asymptomatic.

 


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  		Figure 5. 2-year-old boy with neurofibromatosis type 1. (a) Axial T1 weighted image. Normal appearance to the intracranial optic nerves and chiasma. Enlargement of the right intraorbital optic nerve. (b) Axial CT after contrast infusion, 18 months later, demonstrates a large solid tumour of the chiasma; the left cystic component could either be tumour or an entrapment arachnoidal cyst.

 
In the non-NF-1 group, histological study (11 cases) showed grade I astrocytoma in 10 of the children (pilocytic astrocytoma in 7 cases) and grade II astrocytoma in one case. All the children in this group were treated by surgery (partial, subtotal or total resection: 11 cases), radiotherapy (isolated or after surgery: 5 cases) and/or chemotherapy (4 cases). No death occurred in this group.


   Discussion
Top
 Abstract
 Introduction
 Material and methods
 Results
 Discussion
References
 
The current study analysed tumours of the optic pathways in the presence or absence of NF-1. Both types are generally described as low grade astrocytomas but their courses may be different and the exact nature of the lesion observed in association with NF-1 remains unclear. In these cases, the natural history of such lesions can be unpredictable. In most cases nowadays, children with NF-1 undergo MRI and true optic pathway tumours are discovered in some patients even without initial clinical signs. There is a need for further knowledge about the imaging characteristics of these lesions, because it is not desirable to undertake histological studies or treatment when they are quiescent. The purpose of our study was to determine whether imaging can aid in the follow-up of these children.

These tumours occur in young children, generally before the age of 5 years. As in other comparative studies [2–5], there was no difference in the mean age of discovery between the two groups. Listernick et al [6, 7] did not find any children older than 6 years, without anomaly of the optic pathways, who developed a symptomatic tumour or in whom tumour growth was rapid. This suggests that efforts to detect such tumours in this location in children with NF-1 should be made before the age of 6 years.

It is not possible to compare the initial clinical signs in our two groups, because the circumstances of imaging are not the same. All children without NF-1 in the present study had clinical symptoms in relation to the tumour. 10 (71%) of the children among the 14 who had NF-1 were asymptomatic, in agreement with the 60–75% ofasymptomatic patients reported in other series [5, 6, 8]. This could be related to the location and size of these tumours. The commonest clinical manifestation of these tumours is decreased visual acuity. Intracranial hypertension and nystagmus are encountered with expansive chiasmatic tumours [3]. Precocious puberty in patients with NF-1 is a rare but evocative finding in optic chiasma tumours, resulting in hypothalamic dysfunction [4, 9]. In our study, we observed one case of precocious puberty in a child with a tumour of the optic chiasma. According to Listernick et al [7], precocious puberty never occurs in a child with NF-1 in the absence of a a tumour of the optic chiasma, but in another series glioma of the optic pathway was not encountered in all cases [10]. Consequently, children who have NF-1 should always be carefully examined for clinical signs of precocious puberty [11]. Although no increase in the incidence of optic glioma has previously been described when there is an association of NF-1 and Noonan syndrome, we observed two such cases.

Visual evoked potentials were abnormal in all cases within the present series who underwent this examination. This is a sensitive but non-specific test for the presence of an optic tumour. Visual evoked potentials may be of value in the decision regarding treatment and follow-up of young or asymptomatic children [12].

As in other studies [2, 7], we observed a statistically significant difference between the two groups regarding the location of these tumours. The lesion involved the optic nerves in most of the NF-1 group. Bilateral optic nerve tumours, regardless of the portion of the optic nerve involved, are a specific neuroradiological sign of NF-1 [7, 13, 14]. In the absence of NF-1, tumours were predominantly located in the chiasma. None of the children without NF-1 had an isolated optic nerve lesion. This difference in location may partly explain the difference in clinical patterns, and perhaps the difference in prognosis [15].

The morphology and structure of these tumours also differ depending on whether or not there is associated NF-1. In children with NF-1, the lesion of the optic nerves corresponds either to a tubular and tortuous widening of the nerve, or to a spindle-shaped mass. In patients who have NF-1, Stern et al [15] emphasized the particular anatomopathological architecture of these tumours, which consists of circumferential perineural infiltration extending into subarachnoid spaces and generally preserving the central optic nerve. This tumour morphology is visible on T1 weighted images, giving the nerve a spindle shape that is isointense to the cerebral parenchyma. T2 weighted sequences show a hyperintense signal corresponding to the gliomatosis, which surrounds hypointense nerve fibres [14, 16, 17]. Fat saturated contrast enhanced T1 weighted images can be useful in depicting the extent of the lesion [18]. Proliferation involves an elongation of the nerve, which develops a tortuous appearance. The fact that the lesion develops perineurally, without involvement of the neurons at the initial stage, may explain the limited effect on visual function. In the chiasma, these tumours are typically small and homogeneous, have no cystic component, and are variably enhanced by contrast media. In three of the present children with NF-1, a chiasmal lesion extended into the optic nerves, and in two others it extended into the posterior optic tract. These features suggest a tumoral process that infiltrates the entire optic tract.

In patients who do not have NF-1, tumours of the optic pathways have the same imaging features as pilocytic astrocytomas at other sites [19]. They are generally round, well delineated masses with a cystic component and a solid portion. They are intensely and homogeneously enhanced by contrast media. Histopathological examination shows intraneural growth of the tumour in most cases [15].

Other imaging anomalies were observed in children with NF-1. In 12 (86%), we noted focal hyperintensities on T2 weighted sequences. This incidence is higher than that found overall in NF-1 (50–70%) [20–22]. This increased frequency of these lesions in children who have both NF-1 and a tumour of the optic pathways has been found by others [20, 22, 23] and the question of a possible relationship between these hyperintense signals and the natural history of these tumours remains. We also noted the presence of other cerebral tumours in 3 of the 14 children with NF-1. This association between gliomas of the optic pathways and other tumours of the central nervous system has also been reported [23, 24], in particular in children younger than 10 years of age [8].

We studied the natural course of these tumours only in the NF-1 group, because all the children who did not have NF-1 were treated. MRI demonstrated changes of the optic pathway tumour in only five of our children with NF-1, with a progression in size in four children. This was found by Listernick et al [3] in the same proportion of patients. Clinical signs were associated with progression of the tumour in only one child, who died owing to this progression. In this case, imaging findings were the same as in the non-NF-1 group. The majority of these lesions are stable. However, as stressed in many publications, the course may range from spontaneous regression [5, 25–28] to aggressive development [29–31]. The period of follow-up in our study does not permit long-term assessment of survival [4]. The overall survival rate can be rather worse in NF-1, because children with NF-1 develop other tumours [2, 4, 32]. In our series, two children had another tumour, evolution of which was fatal.

The course of the optic lesions is often unpredictable [31]. We found no predictive MRI criterion of progression of these tumours in children with NF-1. Initial localization, enhancement and structure of the tumour were not correlated with course. Histologically, pilocytic astrocytomas appear to be a very mixed group of tumours. There are no macroscopic or microscopic histopathological criteria that predict the course. Assessment of proliferative activity with the MIB-1 labelling index (expression of proliferative cell nuclear antigen) does not assist in clinical decision-making, although the MIB-1 increased to 15.2% and 18% in two patients with NF-1 who developed highly malignant gliomas 6 years and 6.5 years after irradiation [33]. Flow cytometry analysis also fails to indicate subsequent tumour development [34]. After treatment, one study has shown that, in NF-1, relapse-free survival improves with increasing age, and with chemotherapy and radiotherapy [35]. Better comprehension of the genetic modifications present in these tumours, such as inactivation of the p53 gene and amplification of epidermal growth factor, may provide other clues [36].

Screening for tumours of the optic pathways in asymptomatic children who harbour NF-1 remains a subject of debate. The consensus view does not recommend the routine use of MRI in a child on whom the diagnosis of NF-1 has just been made [1], as MRI does not modify the follow-up or treatment of NF-1 [6, 7]. Nevertheless, brain MRI can provide additional arguments in favour of the diagnosis of NF-1. Some advocate the presence of specific MRI anomalies, such as focal T2 hyperintensities or widening of the space between the optic nerves, among diagnostic criteria [21, 22, 37]. Once the diagnosis has been made, this examination can be used as a reference. If the child develops clinical signs, this will permit one to judge any progression of the tumour [24]. This should not, however, overshadow the importance of clinical examination, which remains fundamental in the follow-up, supplemented by screening with visual evoked potentials [12].

The present study suggests that optic gliomas that develop in children with NF-1 differ from the optic pathway lesions found in children who do not have NF-1. In NF-1, optic pathway tumours occur predominantly anterior to the chiasma, and may correspond to perineural gliomatosis rather than true pilocytic astrocytomas. They have only a slight tendency to progress but chiasma location can occur, sometimes with a different course. In asymptomatic children with NF-1 in our study, initial imaging provided no predictive criteria of tumour progression.

Received for publication May 25, 2000. Revision received August 29, 2000. Accepted for publication September 25, 2000.


   References
Top
 Abstract
 Introduction
 Material and methods
 Results
 Discussion
 References
 

  1. Neurofibromatosis Conference statement. National Institutes of Health Consensus Development Conference. Arch Neurol 1988;45:575–8[Medline]
  2. Deliganis A, Russel Geyer J, Berger M. Prognostic significance of type 1 neurofibromatosis (von Recklinghausen disease) in childhood optic glioma. Neurosurgery 1996;38:1114–9.[Medline]
  3. Listernick R, Darling C, Greenwald M, Strauss L, Charrow J. Optic pathway tumors in children: the effect of neurofibromatosis type 1 on clinical manifestations and natural history. J Pediatr 1995;127:718–22.[Medline]
  4. Cappelli C, Grill J, Raquin M, Pierre-Kahn A, Lellouch-Tubiana A, Terrier-Lacombe MJ, et al. Long-term follow up of 69 patients treated for optic pathway tumours before the chemotherapy era. Arch Dis Child 1998;79:334–8.[Abstract/Free Full Text]
  5. Shuper A, Horev G, Kornreich L, Michowiz S, Weitz R, Zaizov R, et al. Visual pathway glioma: an erratic tumour with therapeutic dilemmas. Arch Dis Child 1997;76:259–63.[Abstract/Free Full Text]
  6. Listernick R, Charrow J, Greenwald M, Mets M. Natural history of optic pathway tumors in children with neurofibromatosis type 1: a longitudinal study. J Pediatr 1994;125:63–6.[Medline]
  7. Listernick R, Louis DN, Packer RJ, Gutmann DH. Optic pathway gliomas in children with neurofibromatosis 1: consensus statement from the NF1 Optic Pathway Glioma Task Force. Ann Neurol 1997;41:143–9.[Medline]
  8. Friedman JM, Birch P. An association between optic glioma and other tumours of the central nervous system in neurofibromatosis type 1. Neuropediatrics 1997;28:131–2.[Medline]
  9. Pomeranz SJ, Shelton JJ, Tobias J, Soila K, Altman D, Viamonte M. MR of visual pathways in patients with neurofibromatosis. Am J Neuroradiol 1987;8:831–6.[Abstract]
  10. Cnossen MH, Stam EN, Cooiman LC, Simonsz HJ, Stroink H, Oranje AP, et al. Endocrinologic disorders and optic pathway gliomas in children with neurofibromatosis type 1. Pediatrics 1997;100:667–70.[Abstract/Free Full Text]
  11. Habiby R, Silverman B, Listernick R, Charrow J. Precocious puberty in children with neurofibromatosis type 1. J Pediatr 1995;126:364–7.[Medline]
  12. Lund AM, Skovby F. Optic gliomas in children with neurofibromatosis type 1. Eur J Pediatr 1991;150:835–8.[Medline]
  13. Faerber EN, Roman NV. Central nervous system tumors of childhood. Radiol Clin North Am 1997;35:1301–28.[Medline]
  14. Imes RK, Hoyt WF. Magnetic resonance imaging signs of optic nerve gliomas in neurofibromatosis 1. Am J Ophthalmol 1991;111:729–34.[Medline]
  15. Stern J, Jakobiec FA, Housepian EM. The architecture of optic nerve gliomas with and without neurofibromatosis. Arch Ophthalmol 1980;98:505–11.[Abstract]
  16. Brodsky MC. The "pseudo-CSF" signal of orbital optic glioma on magnetic resonance imaging: a signature of neurofibromatosis. Surv Ophthalmol 1993;38:213–8.[Medline]
  17. Seiff SR, Brodsky MC, MacDonald G, Berg BO, Howes EL, Hoyt WF. Orbital optic glioma in neurofibromatosis. Magnetic resonance diagnosis of perineural arachnoidal gliomatosis. Arch Ophthalmol 1987;105:1689–92.[Abstract]
  18. Barakos JA, Dillon WP, Chew WM. Orbit, skull base, and pharynx: contrast-enhanced fat suppression MR imaging. Radiology 1991;179:191–8.[Abstract/Free Full Text]
  19. Lee YY, Van Tassel P, Bruner JM, Moser RP, Share JC. Juvenile pilocytic astrocytomas: CT and MR characteristics. AJR 1989;152:1263–70.[Abstract/Free Full Text]
  20. Braffman B, Naidich TP. The phakomatoses: part I. Neurofibromatosis and tuberous sclerosis. Neuroimaging Clin N Am 1994;4:299–324.[Medline]
  21. DiMario FJ Jr, Ramsby G, Greenstein R, Langshur S, Dunham B. Neurofibromatosis type 1: magnetic resonance imaging findings. J Child Neurol 1993;8:32–9.[Medline]
  22. Van Es SV, North KN, McHugh K, Silva MD. MRI findings in children with neurofibromatosis type 1: a prospective study. Pediatr Radiol 1996;26:478–87.[Medline]
  23. Aoki S, Barkovich AJ, Nishimura K, Kjos BO, Machida T, Cogen P, et al. Neurofibromatosis types 1 and 2: cranial MR findings. Radiology 1989;172:527–34.[Abstract/Free Full Text]
  24. Kuenzle C, Weissert M, Roulet E, Bode H, Schefer S, Huisman T, et al. Follow-up of optic pathway gliomas in children with neurofibromatosis type 1. Neuropediatrics 1994;25:295–300.[Medline]
  25. Brzowski AE, Bazan C, Mumma JV, Ryan SG. Spontaneous regression of optic glioma in a patient with neurofibromatosis. Neurology 1992;42:679–81.[Abstract/Free Full Text]
  26. Leisti EL, Pyhtinen J, Poyhonen M. Spontaneous decrease of a pilocytic astrocytoma in neurofibromatosis type 1. Am J Neuroradiol 1996;17:1961–4.
  27. Liu GT, Lessell S. Spontaneous visual improvement in chiasmal gliomas. Am J Ophthalmol 1992;114:193–201.[Medline]
  28. Parazzini C, Triulzi F, Bianchini E, Agnetti V, Conti M, Zanolini C, et al. Spontaneous involution of optic pathway lesions in neurofibromatosis type 1: serial contrast MR evaluation. Am J Neuroradiol 1995;16:1711–8.[Abstract]
  29. Adams C, Fletcher WA, Myles ST. Chiasmal glioma in neurofibromatosis type 1 with severe visual loss regained with radiation. Pediatr Neurol 1997;17:80–2.[Medline]
  30. Champion MP, Robinson RO. Screening for optic gliomas in neurofibromatosis type 1: the role of neuroimaging. J Pediatr 1995;127:507–8.[Medline]
  31. Strong JA, Hatten HP, Brown MT, Debatin JF, Friedman HS, Oakes WJ, et al. Pilocytic astrocytoma: correlation between the initial imaging features and clinical aggressiveness. AJR 1993;161:369–72.[Abstract/Free Full Text]
  32. Dunn DW, Purvin V. Optic pathway gliomas in neurofibromatosis. Dev Med Child Neurol 1990;32:820–4.[Medline]
  33. Czech T, Slavc I, Aichholzer M, Haberler C, Dietrich W, Dieckmann K, et al. Proliferative activity as measured by MIB-1 labeling index and long-term outcome of visual pathway astrocytomas in children. J Neurooncol 1999;42:143–50.[Medline]
  34. Forsyth PA, Shaw EG, Scheithauer BW, O'Fallon JR, Layton DD, Katzmann JA. Supratentorial pilocytic astrocytomas. A clinicopathologic, prognostic, and flow cytometric study of 51 patients. Cancer 1993;72:1335–42.[Medline]
  35. Chan MY, Foong AP, Heisey DM, Harkness W, Hayward R, Michalski A. Potential prognostic factors of relapse-free survival in childhood optic pathway glioma: a multivariate analysis. Pediatr Neurosurg 1998;29:23–8.[Medline]
  36. Rey JA, Pestana A, Bello MJ. Cytogenetics and molecular genetics of nervous system tumors. Oncol Res 1992;4:321–31.[Medline]
  37. North K, Joy P, Yuille D, Cocks N, Mobbs E, Hutchins P, et al. Specific learning disability in children with neurofibromatosis type 1: significance of MRI abnormalities. Neurology 1994;44:878–83.[Abstract/Free Full Text]



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E. Czyzyk, S. Jozwiak, M. Roszkowski, and R. A. Schwartz
Optic Pathway Gliomas in Children With and Without Neurofibromatosis 1
J Child Neurol, July 1, 2003; 18(7): 471 - 478.
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