Relapsing White Matter Disease and Subclinical Optic Neuropathy: From the National Multiple Sclerosis Society Case Conference Proceedings

A 16-year-old adolescent boy presented with recurrent episodes of weakness and numbness. Brain MRI demonstrated subcortical, juxtacortical, and periventricular white matter T2 hyperintensities with gadolinium enhancement. CSF was positive for oligoclonal bands that were not present in serum. Despite treatment with steroids, IV immunoglobulins, plasmapheresis, and rituximab, he continued to have episodes of weakness and numbness and new areas of T2 hyperintensity on imaging. Neuro-ophthalmologic examination revealed a subclinical optic neuropathy with predominant involvement of the papillomacular bundle. Genetic evaluation and brain biopsy led to an unexpected diagnosis.

Rare predicted deleterious FEZF2 variants are associated with a neurodevelopmental phenotype

FEZF2 encodes a transcription factor critical to neurodevelopment that regulates other neurodevelopment genes. Rare variants in FEZF2 have previously been suggested to play a role in autism, and cases of 3p14 microdeletions that include FEZF2 share a neurodevelopmental phenotype including mild dysmorphic features and intellectual disability. We identified seven heterozygous predicted deleterious variants in FEZF2 (three frameshifts, one recurrent missense in two independent cases, one nonsense, and one complete gene deletion) in unrelated individuals with neurodevelopmental disorders including developmental delay/intellectual disability, autism, and/or attention-deficit/hyperactivity. Variants were confirmed to be de novo in five of seven cases and paternally inherited from an affected father in one. Predicted deleterious variants in FEZF2 may affect the expression of genes that are involved in fate choice pathways in developing neurons, and thus contribute to the neurodevelopmental phenotype. Future studies are needed to clarify the mechanism by which FEZF2 leads to this neurodevelopmental disorder.

CLN2 disease resulting from a novel homozygous deep intronic splice variant in TPP1 discovered using long-read sequencing

Neuronal ceroid lipofuscinosis type 2 (CLN2) is an autosomal recessive neurodegenerative disorder with enzyme replacement therapy available. We present two siblings with a clinical diagnosis of CLN2 disease, but no identifiable TPP1 variants after standard clinical testing. Long-read sequencing identified a homozygous deep intronic variant predicted to affect splicing, confirmed by clinical DNA and RNA sequencing. This case demonstrates how traditional laboratory assays can complement emerging molecular technologies to provide a precise molecular diagnosis.

Pearls & Oy-sters: CSF1R-Related Leukoencephalopathy With Spinal Cord Lesions Mimicking Multiple Sclerosis

CSF1R-related leukoencephalopathy is an autosomal dominant neurologic disorder causing microglial dysfunction with a wide range of neurologic complications, including motor dysfunction, dementia, and seizures. This case report highlights an unusual presentation of CSF1R-related leukoencephalopathy with radiographic spinal cord involvement initially diagnosed as multiple sclerosis. This case highlights the importance of considering adult-onset neurogenetic disorders in the setting of white matter disease. Genetic testing provides a confirmatory diagnosis for an expanding number of adult-onset leukoencephalopathies and informs therapeutic decision-making.

Two cases of MT-ND5-related mitochondrial disorder misdiagnosed as seronegative neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease primarily affecting the optic nerves and spinal cord, which is usually associated with anti-aquaporin-4 antibodies. Here, we present two individuals who were negative for anti-aquaporin-4 antibodies and were initially diagnosed with seronegative NMOSD. Each patient's clinical course and radiographic features raised suspicion for an alternative disease process. Both individuals were found to have pathogenic variants of MT-ND5, encoding subunit 5 of mitochondrial complex I, ultimately leading to a revised diagnosis of a primary mitochondrial disorder. These cases illustrate the importance of biochemical and genetic testing in atypical cases of NMOSD.

[Diagnostic value of color-coded Doppler sonography in neuro-otologic disorders]

PURPOSE

The successful introduction of Doppler and Color-Coded Doppler Sonography (CCDS) in the field of Otorhinolaryngology has improved the diagnostic sonographic value for several diseases of the head and neck region, e. g. in hemangiomas and vascular malformations. The diagnostic value of CCDS for examination of the extracranial brain supplying vessels in combination with neuro-otologic disorders is still under controversial discussion.

MATERIALS AND METHODS

We investigated the diagnostic CCDS findings for 215 patients suffering from different neuro-otologic disorders. All patients were classified into 4 groups according to the different disorder entity (sudden deafness, tinnitus, vestibular neuropathy, combined diagnosis). The frequency of pathologic CCDS findings was correlated with the different groups using sonographic parameters such as atherosclerosis, stenosis and intima-media thickness.

RESULTS

Classification of the disorder entities led to the following distribution: Sudden deafness group (85 patients; 40 %), Tinnitus group (44 patients; 20 %), Vestibular neuropathy group (41 patients; 19 %), Combined diagnosis group (45 patients; 21 %). Sonographic evaluation of atherosclerosis was possible in 76 cases (35 %), changes of the intima-media thickness were observed in 43 cases (20 %) while proof of stenoses was identified in 15 cases (7 %). The evaluation of plaque formation (atherosclerosis) in the sudden deafness group was significantly higher (p < 0.01) than in all other groups although the combined diagnosis group demonstrated certain tendencies (p < 0.08) without significant correlation.

CONCLUSION

Our results reinforce the hypothesis of a vascular genesis of sudden deafness and seem to offer the possibility of sonographic differentiation between neuro-otologic disorder entities by use of CCDS. In contrast, it seems that the role of CCDS is negligible for individual diagnostic purposes.

Karotisangiographie bei zentro-lateralen Schädelbasisfrakturen?

BACKGROUND

In latero-basal, central or spheno-fronto-orbital skull base fractures the internal carotid artery is more frequently involved in severe lesions than expected.

PATIENTS AND METHODS

Between 1996 and 2003 we examined 684 patients with Glasgow Coma Scales (GCS) between 2 and 15, median 7.2, using computed tomography (CT). In suspicion of a latero-basal, central or spheno-fronto-orbital fractur they got an additional high resolution skull base CT. If the bony canal of the internal carotid artery (ICA) was involved the patient underwent digital subtraction angiography (DSA). The ICA lesion was treated either interventional neuroradiologically, by surgery or only conservatively.

RESULTS

Of the 684 patients 33 (4.8 %) had fractures of the ICA bony canal and therefore underwent DSA. Among them were 25 men and 8 women (mean age 35.3 years). Lesions of the ICA were seen in 1.9 % of the patients. A traumatic cavernous-carotid fistula was found in 7 patients (1 %) and in 6 patients (0.9 %) a dissection and/or an aneurysm of the ICA was diagnosed. Six of the patients had clinical symptoms. The lesions were treated primarily interventional neuroradiologically (n = 5) as well as surgically in two cases by clipping the aneurysm and closing the sphenoid sinus, respectively.

CONCLUSIONS

Vessel lesions of the ICA in skull base fractures and involvement of the bony carotid canal are more frequent than mentioned in current literature. A solid diagnosis can only be achieved by DSA. Early diagnosis and treatment is important for improving the prognosis of these often multiply injured patients.

The role of endonasal surgery in the management of frontoethmoidal osteomas

Recently endonasal surgery has been considered to be a valuable contribution in the management of paranasal sinus osteoma. A retrospective evaluation study of 34 frontoethmoidal osteomas (23 frontal and 11 ethmoidal osteomas) treated at a tertiary care facility from 1990 to 1999 is presented. Twenty three osteomas (68%) were resected endonasally. Eleven osteomas (32%) were removed using an osteoplastic frontal sinus approach with coronal incision. In 5 cases of huge osteomas originating at the anterior frontal sinus wall, reconstruction of the resected anterior-frontal sinus wall was achieved by autologous outer table grafts harvested from the parietal region. Endoscopic and radiological follow-up ranging from 1 to 32 months showed three incomplete endonasal osteoma resections. Complete osteoma removal was achieved via endonasal revision surgery in two of these cases, while the third small residual osteoma remains under observation. There was no case of osteoplastic osteoma removal where incomplete osteoma resection became obvious during follow-up. Ethmoidal osteomas without extrasinusal extension can be resected endonasally. The endonasal approach should be considered also for frontal sinus osteomas if (1) sufficient frontal sinus access can be achieved endonasally, (2) the osteoma is placed medially to a virtual sagittal plane through the lamina papyracea, and (3) the tumour base is at the inferior part of the posterior frontal sinus wall. We favour the osteoplastic frontal sinus approach with coronal incision if an external approach is required to achieve tumour resection with the best aesthetic results.