Optic pathway tumor in children: Toward a new classification for neurosurgical use.

OBJECT: Optic pathway tumors (OPT) represent a challenge for pediatric neurosurgeons. Role of surgery is debated due to the high risk of iatrogenic damage, and in lasts decades it lost its importance in favor of chemotherapy. However, in some cases surgery is necessary to make biomolecular and histological diagnosis, to manage intracranial hypertension (IH) and to cooperate with medical therapies in controlling tumor relapse. With the aim to standardize selection of surgical OPT cases, we propose a simple, practical and reproducible classification. METHODS: We retrospectively analyzed data of 38 patients with OPT treated at our institution (1990-2018). After careful analysis of MRI images, we describe a new classification system. Group 1: lesion limited to one or both optic nerve(s). Group 2: chiasmatic lesions extending minimally to hypothalamus. Group 3: hypothalamo-chiasmatic exophitic lesions invading the third ventricle; they can be further divided on the base of concomitant hydrocephalus. Group 4: hypothalamo-chiasmatic lesions extending widely in lateral direction, toward the temporal or the frontal lobes. Patients' data and adopted treatment are reported and analyzed, also depending on this classification. RESULTS: Twenty children were operated on for treatment of OPT during the study period. Permanent clinical impairment was noted in 5 (25%) of operated patients, while visual improvement was noted in 1 patient. OS rate was 100% at 5 years, with a median follow up of 9 years (ranging from 2 to 23). Prevalence of intracranial hypertension and proportion of first-line surgical treatment decision were significantly higher in groups 3-4 compared to groups 1-2 (P<0.001 for both tests). CONCLUSION: Surgery can offer a valuable therapeutic complement for OPT without major risk of iatrogenic damage. Surgery is indispensable in cases presenting with IH, as in groups 3 and 4 lesions. Eligibility of patients to surgery can be based on this new classification system.

Optic pathway gliomas: neoplasms, not hamartomas.

IMPORTANCE: Optic pathway gliomas are an important neuro-ophthalmic cause of vision loss in children. Their management depends on whether they are considered neoplasms or hamartomas. OBJECTIVE: To outline the evidence that optic pathway gliomas are slowly growing neoplasms and not hamartomas. DESIGN: Review of relevant studies in the literature. SETTING: The authors are from a pediatric tertiary referral center. RESULTS: The growth patterns and histopathology of optic pathway gliomas are more consistent with those of neoplasms. Spontaneous regression, thought to be a characteristic of hamartomas, can be seen in neoplasms of other types as well as in optic pathway gliomas. Chemotherapy used in low-grade gliomas has been shown to halt or improve vision loss in optic pathway gliomas in many cases. CONCLUSIONS AND RELEVANCE: Optic pathway gliomas are not hamartomas but truly are neoplasms. Thus, patients should be followed up closely, and chemotherapies should be used when clinical progression occurs. Other more directed therapies will certainly be used in the future.

The adverse influence of attention-deficit disorder with or without hyperactivity on cognition in neurofibromatosis type 1.

AIM: A substantial proportion of patients with neurofibromatosis type 1 (NF1) have attention-deficit disorder with or without hyperactivity (AD[H]D). This study explored the influence of AD(H)D symptoms on the intellectual profile of patients with NF1. METHOD: We retrospectively analysed neuropsychological data from 114 children (66 males, 48 females; age range 6-16y; mean age 9y 3mo [SE 3mo]) with NF1 from an NF1 outpatients department. Assessment included psychiatric diagnosis of AD(H)D (DSM-IV-TR criteria) and intelligence testing (Wechsler Intelligence Scale for Children, German version). Magnetic resonance images were available for all patients, intracranial findings being an exclusion criterion. The effects of AD(H)D symptoms on intelligence and on the cognitive profile were tested by analyses of variance. RESULTS: Patients with AD(H)D symptoms performed significantly worse than those without AD(H)D symptoms on all intelligence measures (main effects for Full-scale, Verbal, and Performance IQ; p<0.005). Subtests typically impaired in patients with NF1 (visuospatial skills and arithmetic) were not specifically influenced by AD(H)D symptoms. There were no differences between AD(H)D subtypes. INTERPRETATION: AD(H)D symptoms have a negative impact on the intellectual development of children with NF1. This impact seems to be of an unspecific nature, with a general attenuation of the cognitive profile.

Radiological classification of optic pathway gliomas: experience of a modified functional classification system.

Optic pathway gliomas (OPGs) in childhood are associated with neurofibromatosis type 1 (NF1) and since 1958 have been classified anatomically using the Dodge classification (DC). MR scanning permits a more detailed anatomical description than can be classified by this historical system. A modified Dodge classification (MDC) has been applied to MRI scans from a cohort of 72 patients (36.1% NF1-positive) from 4 centres participating in an international clinical trial. The MDC was feasible, applicable and more detailed than the original DC. NF1-positive cases more commonly involved both optic nerves (p = 0.021) and other multiple locations (p = 0.001). NF1-negative tumours more commonly involved the central chiasm (p = 0.005) and hypothalamus (p = 0.003). Fewer hypothalamus-positive tumours were associated with optic nerve involvement (p = 0.009), whereas more were associated with central chiasm involvement (p<0.001). From diagnosis to follow-up, there was concordance between DC and MDC in 51/72 cases (70.8%). The MDC is therefore proposed for use in clinical trials of new treatments for OPGs.

[A follow-up of patients with anterior optic tract glioma concurrent with type 1 neurofibromatosis].

Fifty-nine patients with anterior optic tract (AOT) lesion concurrent with type neurofibromatosis (NF-1) were followed up for 1 to 36 years (median 5 years). Based on the study, the authors identified several grades of the disease: - stabilization without intervention; - stabilization after treatment; - insignificant negative changes as a slight tumor growth and a further stabilization of the process; - occasionally negative changes irrespective of treatment. The behavior of a tumor is unpredictable. The onset of progression in infancy is a poor predictor. Ophthalmological symptoms are not the criterion that can be used to make a prognosis. The prognosis is largely determined by neurovisualization techniques and primarily magnetic resonance imaging. A uniform slight thickening of AOT structures irrespective of the extent of the process along the AOT should be referred to as a good prognosis. There was no spontaneous tumor regression in any case. By taking into account the beneficial effect of radiotherapy, the authors consider it expedient to use it as monotherapy and in combination with surgery. Bypass surgery on the spinal fluid system frequently fails to entirely solve the problem intracranial hypertension.