- Visual loss (HP:0000572): Loss of visual acuity (implying that vision was better at a certain time point in life). Otherwise the term reduced visual acuity should be used (or a subclass of that). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2086)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2086)
- Optic atrophy (HP:0000648): Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2086)
- Neurofibroma (HP:0001067): A benign peripheral nerve sheath tumor that generally appears as a soft, skin-colored papule or small subcutaneous nodule. Individuals with neurofibromatosis can have numerous neurofibromas. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2086)
- Reduced visual acuity (HP:0007663). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2086)
- Hydrocephalus (HP:0000238): Hydrocephalus is an active distension of the ventricular system of the brain resulting from inadequate passage of CSF from its point of production within the cerebral ventricles to its point of absorption into the systemic circulation. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Strabismus (HP:0000486): A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Proptosis (HP:0000520): An eye that is protruding anterior to the plane of the face to a greater extent than is typical. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Ophthalmoplegia (HP:0000602): Paralysis of one or more extraocular muscles that are responsible for eye movements. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Blindness (HP:0000618): Blindness is the condition of lacking visual perception defined as a profound reduction in visual perception. On the 6m visual acuity scale, blindness is defined as less than 3/60. On the 20ft visual acuity scale, blindness is defined as less than 20/400. On the decimal visual acuity scale, blindness is defined as less than 0.05. Blindness is typically characterized by a visual field of no greater than 10 degrees in radius around central fixation. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Abnormality of the nervous system (HP:0000707): An abnormality of the nervous system. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Precocious puberty (HP:0000826): The onset of secondary sexual characteristics before a normal age. Although it is difficult to define normal age ranges because of the marked variation with which puberty begins in normal children, precocious puberty can be defined as the onset of puberty before the age of 8 years in girls or 9 years in boys. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Papilledema (HP:0001085): Papilledema refers to edema (swelling) of the optic disc secondary to any factor which increases cerebral spinal fluid pressure. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Visual field defect (HP:0001123). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Seizure (HP:0001250): A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Global developmental delay (HP:0001263): A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Growth delay (HP:0001510): A deficiency or slowing down of growth pre- and postnatally. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Vomiting (HP:0002013): Forceful ejection of the contents of the stomach through the mouth by means of a series of involuntary spasmic contractions. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Nausea (HP:0002018): A sensation of unease in the stomach together with an urge to vomit. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Headache (HP:0002315): Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Vertigo (HP:0002321): An abnormal sensation of spinning while the body is actually stationary. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Developmental regression (HP:0002376): Loss of developmental skills, as manifested by loss of developmental milestones. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
- Fatigable weakness (HP:0003473): A type of weakness that occurs after a muscle group is used and lessens if the muscle group has some rest. That is, there is diminution of strength with repetitive muscle actions. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2086)
These phenotypes are associated with the disease Optic pathway glioma (ORPHA:2086).