Isolated Sixth Nerve Palsies in a Child With Familial Hemophagocytic Lymphohistiocytosis Type 2.

ABSTRACT: A previously healthy 2-year-old boy presented with a left sixth cranial nerve palsy. There was a family history of multiple sclerosis and optic neuritis. Neuroimaging showed multiple foci of T2/FLAIR hyperintense signal abnormality in both cerebral hemispheres and in the brainstem. The initial diagnosis was suspicious for demyelinating disease. However, there was no clinical improvement after a course of corticosteroids, and there was no change in his follow-up MRI. He later developed bilateral sixth nerve palsies, with esotropia addressed with bilateral medial rectus botulinum toxin injections. A brain biopsy was planned. However, his 3-month-old sister was separately admitted for fever and pancytopenia. She had markedly elevated ferritin, D-dimer, triglycerides, sIL-2R, CXCL9, and IL-18 and low fibrinogen. Her bone marrow biopsy showed hemophagocytosis. Genetic testing of both siblings revealed biallelic mutations in the PRF1 locus. The final diagnosis of familial hemophagocytic lymphohistiocytosis Type 2 was made. Both siblings underwent chemotherapy. The boy's sixth nerve palsies and MRI abnormalities resolved. Both siblings then went on to undergo bone marrow transplant.

High Altitude as a Risk Factor for the Development of Nonarteritic Anterior Ischemic Optic Neuropathy.

BACKGROUND: Episodic high-altitude exposure leads to optic disc edema and retinopathy. It is uncertain whether high-altitude exposure is a risk factor for nonarteritic anterior ischemic optic neuropathy (NAION). METHODS: We performed a single-center, retrospective, cross-sectional case study of 5 patients with high-altitude-associated NAION (HA-NAION) from April 2014 to April 2019. Main study parameters included known vascular risk factors for NAION, evolution of visual acuity, visual field, optic disc, and macula measurements. RESULTS: We studied 5 eyes of 5 patients with HA-NAION that occurred at 7,000-9,000 ft above sea level, 28 patients with classic NAION that developed at sea level (normal altitude NAION or NA-NAION), and 40 controls. All 5 patients with HA-NAION had clinically confirmed NAION by a neuro-ophthalmologist within 3-21 days of onset and comprehensive follow-up evaluations (average follow-up of 23 months). Other than high-altitude exposure, 4 of 5 patients had undiagnosed obstructive sleep apnea (OSA, apnea-hypopnea index 5.4-22.2) and 1 had systemic vascular risk factors. All patients had disc-at-risk in the contralateral eye. The best-corrected distance visual acuity was 20/20 to 20/70 (median logMAR 0) at presentation and 20/70 to counting finger (median logMAR 0) at ≥6 months. Automated static perimetry revealed average mean deviation of -18.6 dB at presentation and -22.1 dB at ≥6 months. The average retinal nerve fiber layer was 244 µm (80-348 µm) at onset and 59 µm (55-80 µm) at ≥6 months. The average ganglion cell complex thickness was 50 µm (43-54 µm) at onset and 52 µm (50-55 µm) at ≥6 months. The patients with OSA were started on home continuous positive airway pressure treatment. Visual outcomes were similar in patients with HA-NAION and NA-NAION. - After addressing all NAION risk factors, no new events occurred in the HA-NAION group within 2-8 years with or without repeat high-altitude exposure. CONCLUSIONS: NAION can occur under high-altitude conditions. HA-NAION is associated with relatively younger age at onset, disc-at-risk, and OSA. These patients exhibit a relatively progressive course of vision loss after initial onset and severe thinning of optic nerves on optical coherence tomography. Treatment for OSA is recommended, especially with repeated high-altitude exposure.

Multicolor Imaging of Optic Disc Drusen.

ABSTRACT: Optic disc drusen (ODD) are calcified deposits at the anterior optic nerve that are often detectable by ophthalmic imaging, including optical coherence tomography and fundus autofluorescence imaging. Multicolor (MC) imaging is a novel modality that captures reflectance of blue, green, and near-infrared laser lights with confocal scanning laser ophthalmoscopy to rapidly acquire high-resolution reflectance images of the optic disc and retina. Here, we show an eye with 3 MC imaging features of ODD, including prominent green hyperreflectance of the optic disc, green sheathing of the papillary and peripapillary vasculature (arterioles > venules), and presence of orange superficial ODD. MC imaging can provide rapid high-resolution assessment of eyes with optic nerve head elevation to help distinguish pseudopapilledema vs papilledema in children and adults without dilation, and future large studies incorporating MC imaging will help determine its contribution in the diagnosis and monitoring of ODD and assessment of other causes of optic nerve head elevation.

Update in Pediatric Pseudotumor Cerebri Syndrome.

Pseudotumor cerebri syndrome (PTCS) is a rare condition in children presenting with headache and papilledema from increased intracranial pressure that can cause significant morbidity. This can be idiopathic, also known as idiopathic intracranial hypertension or primary intracranial hypertension, or can be secondary to medications and associated medical conditions. Given the threat to vision, early detection and treatment is needed in all age groups. However, identifying papilledema or pseudopapilledema in children presents unique challenges sometimes as a result of differences between prepubertal and postpubertal children, further elucidating the complex pathophysiology. Management requires brain imaging, lumbar puncture, and frequent eye exams with medical and rarely surgical treatment. Visual outcomes in children are favorable if caught early and management can be prolonged over years. Pediatric PTCS is different from adult PTCS in many ways, and this review will focus on the most updated definitions of the disease, theories of pathophysiology, management, and treatment in the pediatric population.

CRB1-associated retinal dystrophy presenting as self-resolving opsoclonus and posterior uveitis.

PURPOSE: To describe the unusual case of inflammatory CRB1-associated retinal dystrophy that initially presented with self-resolving opsoclonus. OBSERVATIONS: We report the case of a now 2-year-old female who developed opsoclonus without myoclonus at the age of 4 months. An extensive workup for neuroblastoma and other systemic diseases was unremarkable, and all unusual eye movements self-resolved at age 10 months. Twenty-one months after initial presentation, she began having reduced visual behaviors, and comprehensive ophthalmic exam at that time revealed recurrent saccadic intrusions as well as severe, chronic retinal inflammation and dystrophic changes. An extensive infectious and inflammatory workup was negative. Genetic sequencing revealed two variants in CRB1: a heterozygous missense mutation and a heterozygous novel deletion involving exon 12. The patient was treated with monthly infliximab and methylprednisolone infusions with improvement in her optic disc and macular capillary leakage. The patient's 8-month-old sister also harbored the same variants in CRB1 and had early signs of retinal dystrophy and peripheral vascular leakage on exam. CONCLUSION: Saccadic intrusions may be the first sign of a retinal dystrophy, and infants and children with this presentation should undergo a complete eye exam. We further highlight the link between CRB1-associated retinal dystrophy and inflammation, and how systemic steroids and tumor necrosis factor alpha (TNF-α) inhibitors may be effective therapies. Finally, we report a novel deletion in CRB1 that is likely highly penetrant.

Anatomic and Thermometric Analysis of Cranial Nerve Palsy after Laser Amygdalohippocampotomy for Mesial Temporal Lobe Epilepsy.

BACKGROUND: Laser interstitial thermal therapy (LITT) is a minimally invasive therapy for treating medication-resistant mesial temporal lobe epilepsy. Cranial nerve (CN) palsy has been reported as a procedural complication, but the mechanism of this complication is not understood. OBJECTIVE: To identify the cause of postoperative CN palsy after LITT. METHODS: Four medial temporal lobe epilepsy patients with CN palsy after LITT were identified for comparison with 22 consecutive patients with no palsy. We evaluated individual variation in the distance between CN III and the uncus, and CN IV and the parahippocampal gyrus using preoperative T1- and T2-weighted magnetic resonance (MR) images. Intraoperative MR thermometry was used to estimate temperature changes. RESULTS: CN III (n = 2) and CN IV palsies (n = 2) were reported. On preoperative imaging, the majority of identified CN III (54%) and CN IV (43%) were located within 1 to 2 mm of the uncus and parahippocampal gyrus tissue border, respectively. Affected CN III and CN IV were more likely to be found < 1 mm of the tissue border (PCNIII = .03, PCNIV < .01; chi-squared test). Retrospective assessment of thermal profile during ablation showed higher temperature rise along the mesial temporal lobe tissue border in affected CNs than unaffected CNs after controlling for distance (12.9°C vs 5.8°C; P = .03; 2-sample t-test). CONCLUSION: CN palsy after LITT likely results from direct heating of the respective CN running at extreme proximity to the mesial temporal lobe. Low-temperature thresholds set at the border of the mesial temporal lobe in patients whose CNs are at close proximity may reduce this risk.

Characteristics and Long-term Follow-up of Isolated Vertical Nystagmus in Infancy.

PURPOSE: To determine the clinical characteristics and long-term outcomes of infants who presented with isolated vertical nystagmus. METHODS: The medical records of 114 infants who were diagnosed as having nystagmus from 1996 to 2016 were screened. Patients with vertical nystagmus within the first year of life who had unremarkable magnetic resonance imaging of the brain and demonstrated age-appropriate visual behavior were included. The parents of patients in the final study cohort were contacted by telephone to obtain long-term follow-up information. RESULTS: Eight patients comprised the final cohort. Vertical nystagmus was first observed at a mean age of 1.4 months (range: 1 to 2.5 months) and resolved in 87.5% of patients at a mean age of 3.8 months (range: 2 to 10 months). Vertical nystagmus was intermittent in 62.5%, upbeat in 62.5%, and pendular in 37.5% of patients. One patient's nystagmus did not resolve. Seventy-five percent of patient guardians participated in the telephone questionnaire. The mean age of patients at follow-up was 3.5 years (range: 0.5 to 8.1 years). Isolated iris transillumination was discovered in one patient without other features of albinism. Fifty percent of patients had speech delay requiring intervention. No other developmental delays or general medical conditions were identified. CONCLUSIONS: Nystagmus resolved in 87.5% of patients, all before the first year of life, and speech delay was later identified in half of the patients. [J Pediatr Ophthalmol Strabismus. 2018;55(3):159-163.].

Clinical and Prognostic Significance of Cerebrospinal Fluid Opening and Closing Pressures in Pediatric Pseudotumor Cerebri Syndrome.

BACKGROUND: The purpose of this study was to determine the prognostic utility of closing pressure and volume of cerebrospinal fluid removed with respect to papilledema resolution and headache improvement in pediatric pseudotumor cerebri syndrome. METHODS: This is a retrospective observational study of 93 children with definite pseudotumor cerebri syndrome. The primary outcome measure was time to resolution of papilledema, and the secondary outcome measure was time to resolution of headache. RESULTS: There were no significant differences in gender, age, or body mass index z score observed between subjects with (N = 35) and without (N = 58) documented closing pressure. The median time to resolution of papilledema was not statistically different between children above or equal to and those below the median closing pressure (170 mm of cerebrospinal fluid, n = 31, P = 0.391) or the volume of median cerebrospinal fluid removed (16 mL, n = 19, P = 0.155). There was no statistically significant difference detected in days of headache between the children with opening pressure above and equal to the median (400 mm of cerebrospinal fluid) and the children with opening pressure below the median (n = 44, P = 0.634). CONCLUSIONS: No significant association between closing pressure, amount of cerebrospinal fluid removed, and time to resolution of papilledema due to pseudotumor cerebri syndrome was detected. The diagnostic and therapeutic purposes of either measuring the closing pressure or maximizing the volume of cerebrospinal fluid removed were not evident in these analyses.

Pediatric Pseudotumor Cerebri Syndrome: Diagnosis, Classification, and Underlying Pathophysiology.

Pseudotumor cerebri syndrome (PTCS) is defined by the presence of elevated intracranial pressure in the setting of normal brain parenchyma and cerebrospinal fluid. PTCS can occur in the pediatric and adult populations and, if untreated, may lead to permanent visual loss. In this review, discussion will focus on PTCS in the pediatric population and will outline its distinct epidemiology and key elements of diagnosis, evaluation and management. Finally, although the precise mechanisms are unclear, the underlying pathophysiology will be considered.

Rituximab use in pediatric central demyelinating disease.

BACKGROUND: Rituximab is a B-cell therapy used off-label to reduce relapses in adult demyelinating diseases. There is limited knowledge of its clinical use in pediatric neuromyelitis optica and multiple sclerosis. Demyelinating diseases in children can have high morbidity, and B-cell therapies hold promise for those with a severe course. Our study investigates the clinical experience of safety and efficacy with rituximab in children with demyelinating diseases of the central nervous system. METHODS: This is a retrospective case series of 11 patients with pediatric neuromyelitis optica and multiple sclerosis who received at least one rituximab infusion at the Pediatric Multiple Sclerosis Clinic, University of California, San Francisco. Each patient was infused up to 1000 mg twice 2 weeks apart. Patients were monitored prospectively, and relapse events, laboratories, and adverse reactions were recorded. RESULTS: Eight children with neuromyelitis optica, two with relapsing-remitting multiple sclerosis and one with secondary-progressive multiple sclerosis received rituximab treatment. The median number of cycles was 3. Most patients (82%, n = 9) experienced reduction of relapses after initiating rituximab. There were no serious infections. Infusion reactions were reported in three patients and managed successfully in subsequent infusions with increased pretreatment (dexamethasone and diphenhydramine) and use of slower infusion rates. Rituximab was not discontinued in any child because of side effects; two switched treatment therapy after 4.5 and 11 months because of relapses. CONCLUSIONS: The use of rituximab in our pediatric neuromyelitis optica and multiple sclerosis cohort was overall safe and effective. Larger studies should confirm our observations.