Heidenhain Variant of Creutzfeldtjakob Disease: Diffusion-Weighted MRI and PET Characteristics

How common are seizures in the heidenhain variant of creutzfeldt-jakob disease? A case report and systematic review

The Heidenhain variant of Creutzfeld-Jakob disease (HvCJD) is a relentlessly progressive and fatal neurodegenerative disorder characterised by prominent visual features early in its clinical course. However, seizures are uncommonly reported in HvCJD. The case history of a patient admitted to our institution with HvCJD and seizures is described followed by a systematic review of the association between HvCJD and seizures. A systematic search of the databases Medline, PubMed, and PsycInfo was conducted, from inception to November 2019, using keywords relating to 'Creutzfeldt-Jakob disease' and 'Heidenhain variant', to ascertain the frequency of seizures in HvCJD, as well as, seizure semiology and electrographic features. The Preferred Items Reporting for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed in the construction of this systematic review. All studies, including case reports of patients who met the diagnostic criteria for HvCJD where details pertaining to clinical presentation, imaging, biochemical and EEG findings were available were included. There were 46 articles reporting on a total of 73 patients. Seizures occurred in only four out of 73 cases (5.5%). The semiology of these seizures were focal motor seizures with or without secondary generalisation and occipital lobe seizures. Imaging and electrographic findings were most commonly abnormal in the posterior cerebral cortices (in particular the occipital and occipito-parietal regions). This systematic review suggests that seizures are uncommon in HvCJD despite the frequency of imaging and electrographic abnormalities in the posterior cerebral regions. A key limitation of this systematic review is the variability of publications in terms of incomplete reporting of clinical data, in particular potential under-reporting of seizures, as well as follow up, which may have contributed to the lower frequency of seizures reported in patients with HvCJD.

Multimodal MRI staging for tracking progression and clinical-imaging correlation in sporadic Creutzfeldt-Jakob disease

Diffusion imaging is very useful for the diagnosis of sporadic Creutzfeldt-Jakob disease, but it has limitations in tracking disease progression as mean diffusivity changes non-linearly across the disease course. We previously showed that mean diffusivity changes across the disease course follow a quasi J-shaped curve, characterized by decreased values in earlier phases and increasing values later in the disease course. Understanding how MRI metrics change over-time, as well as their correlations with clinical deficits are crucial steps in developing radiological biomarkers for trials. Specifically, as mean diffusivity does not change linearly and atrophy mainly occurs in later stages, neither alone is likely to be a sufficient biomarker throughout the disease course. We therefore developed a model combining mean diffusivity and Volume loss (MRI Disease-Staging) to take into account mean diffusivity's non-linearity. We then assessed the associations between clinical outcomes and mean diffusivity alone, Volume alone and finally MRI Disease-Staging. In 37 sporadic Creutzfeldt-Jakob disease subjects and 30 age- and sex-matched healthy controls, high angular resolution diffusion and high-resolution T1 imaging was performed cross-sectionally to compute z-scores for mean diffusivity (MD) and Volume. Average MD and Volume were extracted from 41 GM volume of interest (VOI) per hemisphere, within the images registered to the Montreal Neurological Institute (MNI) space. Each subject's volume of interest was classified as either "involved" or "not involved" using a statistical threshold of ± 2 standard deviation (SD) for mean diffusivity changes and/or -2 SD for Volume. Volumes of interest were MRI Disease-Staged as: 0 = no abnormalities; 1 = decreased mean diffusivity only; 2 = decreased mean diffusivity and Volume; 3 = normal ("pseudo-normalized") mean diffusivity, reduced Volume; 4 = increased mean diffusivity, reduced Volume. We correlated Volume, MD and MRI Disease-Staging with several clinical outcomes (scales, score and symptoms) using 4 major regions of interest (Total, Cortical, Subcortical and Cerebellar gray matter) or smaller regions pre-specified based on known neuroanatomical correlates. Volume and MD z-scores correlated inversely with each other in all four major ROIs (cortical, subcortical, cerebellar and total) highlighting that ROIs with lower Volumes had higher MD and vice-versa. Regarding correlations with symptoms and scores, higher MD correlated with worse Mini-Mental State Examination and Barthel scores in cortical and cerebellar gray matter, but subjects with cortical sensory deficits showed lower MD in the primary sensory cortex. Volume loss correlated with lower Mini-Mental State Examination, Barthel scores and pyramidal signs. Interestingly, for both Volume and MD, changes within the cerebellar ROI showed strong correlations with both MMSE and Barthel. Supporting using a combination of MD and Volume to track sCJD progression, MRI Disease-Staging showed correlations with more clinical outcomes than Volume or MD alone, specifically with Mini-Mental State Examination, Barthel score, pyramidal signs, higher cortical sensory deficits, as well as executive and visual-spatial deficits. Additionally, when subjects in the cohort were subdivided into tertiles based on their Barthel scores and their percentile of disease duration/course ("Time-Ratio"), subjects in the lowest (most impaired) Barthel tertile showed a much greater proportion of more advanced MRI Disease-Stages than the those in the highest tertile. Similarly, subjects in the last Time-Ratio tertile (last tertile of disease) showed a much greater proportion of more advanced MRI Disease-Stages than the earliest tertile. Therefore, in later disease stages, as measured by time or Barthel, there is overall more Volume loss and increasing MD. A combined multiparametric quantitative MRI Disease-Staging is a useful tool to track sporadic Creutzfeldt-Jakob- disease progression radiologically.

Bornavirus Encephalitis Shows a Characteristic Magnetic Resonance Phenotype in Humans

OBJECTIVE

The number of diagnosed fatal encephalitis cases in humans caused by the classical Borna disease virus (BoDV-1) has been increasing, ever since it was proved that BoDV-1 can cause human infections. However, awareness of this entity is low, and a specific imaging pattern has not yet been identified. We therefore provide the first comprehensive description of the morphology of human BoDV-1 encephalitis, with histopathological verification of imaging abnormalities.

METHODS

In an institutional review board-approved multicenter study, we carried out a retrospective analysis of 55 magnetic resonance imaging (MRI) examinations of 19 patients with confirmed BoDV-1 encephalitis. Fifty brain regions were analyzed systematically (T1w, T2w, T2*w, T1w + Gd, and DWI), in order to discern a specific pattern of inflammation. Histopathological analysis of 25 locations in one patient served as correlation for MRI abnormalities.

RESULTS

Baseline imaging, acquired at a mean of 11 ± 10 days after symptom onset, in addition to follow-up scans of 16 patients, revealed characteristic T2 hyperintensities with a predilection for the head of the caudate nucleus, insula, and cortical spread to the limbic system, whereas the occipital lobes and cerebellar hemispheres were unaffected. This gradient was confirmed by histology. Nine patients (47.4%) developed T1 hyperintensities of the basal ganglia, corresponding to accumulated lipid phagocytes on histology and typical for late-stage necrosis.

INTERPRETATION

BoDV-1 encephalitis shows a distinct pattern of inflammation in both the early and late stages of the disease. Its appearance can mimic sporadic Creutzfeldt-Jakob disease on MRI and should be considered a differential diagnosis in the case of atypical clinical presentation. ANN NEUROL 2020;88:723-735.

Unusual Clinical Presentations Challenging the Early Clinical Diagnosis of Creutzfeldt-Jakob Disease

The introduction of prion RT-QuIC, an ultrasensitive specific assay for the in vivo detection of the abnormal prion protein, has significantly increased the potential for an early and accurate clinical diagnosis of Creutzfeldt-Jakob disease (CJD). However, in the clinical setting, the early identification of patients with possible CJD is often challenging. Indeed, CJD patients may present with isolated symptoms that remain the only clinical manifestation for some time, or with neurological syndromes atypical for CJD. To enhance awareness of unusual disease presentations and promote earlier diagnosis, we reviewed the entire spectrum of atypical early manifestations of CJD, mainly reported to date as case descriptions or small case series. They included sensory either visual or auditory disturbances, seizures, isolated psychiatric manifestations, atypical parkinsonian syndromes (corticobasal syndrome, progressive supranuclear palsy-like), pseudobulbar syndrome, isolated involuntary movements (dystonia, myoclonus, chorea, blepharospasm), acute or subacute onsets mimicking a stroke, isolated aphasia, and neuropathy. Since CJD is a rare disease and its clinical course rapidly progressive, an in-depth understanding and awareness of early clinical features are mandatory to enhance the overall diagnostic accuracy in its very early stages and to recruit optimal candidates for future therapeutic trials.

Sporadic Creutzfeldt-Jakob disease

Sporadic Creutzfeldt-Jakob disease (CJD), the most common human prion disease, is generally regarded as a spontaneous neurodegenerative illness, arising either from a spontaneous PRNP somatic mutation or a stochastic PrP structural change. Alternatively, the possibility of an infection from animals or other source remains to be completely ruled out. Sporadic CJD is clinically characterized by rapidly progressive dementia with ataxia, myoclonus, or other neurologic signs and, neuropathologically, by the presence of aggregates of abnormal prion protein, spongiform change, neuronal loss, and gliosis. Despite these common features the disease shows a wide phenotypic variability which was recognized since its early descriptions. In the late 1990s the identification of key molecular determinants of phenotypic expression and the availability of a large series of neuropathologically verified cases led to the characterization of definite clinicopathologic and molecular disease subtypes and to an internationally recognized disease classification. By showing that these disease subtypes correspond to specific agent strain-host genotype combinations, recent transmission studies have confirmed the biologic basis of this classification. The introduction of brain magnetic resonance imaging techniques such as fluid-attenuated inversion recovery and diffusion-weighted imaging sequences and cerebrospinal fluid biomarker assays for the detection of brain-derived proteins as well as real-time quaking-induced conversion assay, allowing the specific detection of prions in accessible biologic fluids and tissues, has significantly contributed to the improved accuracy of the clinical diagnosis of sporadic CJD in recent years.

Revisiting the Heidenhain Variant of Creutzfeldt-Jakob Disease: Evidence for Prion Type Variability Influencing Clinical Course and Laboratory Findings

The Heidenhain variant defines a peculiar clinical presentation of sporadic Creutzfeldt-Jakob disease (sCJD) characterized by isolated visual disturbances at disease onset and reflecting the early targeting of prions to the occipital cortex. Molecular and histopathological typing, thus far performed in 23 cases, has linked the Heidenhain variant to the MM1 sCJD type. To contribute a comprehensive characterization of cases with the Heidenhain variant, we reviewed a series of 370 definite sCJD cases. Eighteen patients (4.9%) fulfilled the selection criteria. Fourteen of them belonging to sCJD types MM1 or MM1+2C had a short duration of isolated visual symptoms and overall clinical disease, a high prevalence of periodic sharp-wave complexes in EEG, and a marked increase of cerebrospinal fluid proteins t-tau and 14-3-3 levels. In contrast, three cases of the MM 2C or MM 2+1C types showed a longer duration of isolated visual symptoms and overall clinical disease, non-specific EEG findings, and cerebrospinal fluid concentration below threshold for the diagnosis of "probable" CJD of both 14-3-3 and t-tau. However, a brain DWI-MRI disclosed an occipital cortical hyperintensity in the majority of examined cases of both groups. While confirming the strong linkage with the methionine genotype at the polymorphic codon 129 of the prion protein gene, our results definitely establish that the Heidenhain variant can also be associated with the MM 2C sCJD type in addition to the more common MM1 type. Likewise, our results highlight the significant differences in clinical evolution and laboratory findings between cases according to the dominant PrPSc type (type 1 versus type 2).

Neuroimaging of dementia

Dementia, whether secondary to Alzheimer disease or another process, is a significant cause of morbidity and mortality worldwide. Although dementia remains a clinical diagnosis, for many years imaging has served as a key component in the assessment of patients with cognitive impairment. There have been tremendous advancements in the neuroimaging of dementia over the past decade, moving the field past the rule-out dogma toward ruling in specific pathophysiologic processes. This article is written for the practicing clinician, to provide a review of neuroimaging findings associated with selected degenerative and nondegenerative forms of dementia.

A case of Creutzfeldt-Jakob disease mimicking corticobasal degeneration: FDG PET, SPECT, and MRI findings

A 58-year-old woman was admitted with left-sided decreased sensation, ataxia, and left "alien" hand and leg. Brain SPECT and PET showed hypoperfusion and hypometabolism in the right frontoparietal cortices, including the primary sensorimotor cortex, and temporal cortex. MRI demonstrated matching-restricted diffusion and fluid-attenuated inversion recovery hyperintensity. Corticobasal degeneration was suspected initially. The patient declined rapidly, and the diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) was made based on cerebrospinal fluid biomarkers. CJD can present with symptoms similar to other disorders. This case illustrates that CJD can mimic a rare neurodegenerative disorder, cortico-basal degeneration, both clinically and by neuroimaging.

Glucose metabolism in sporadic Creutzfeldt-Jakob disease: a statistical parametric mapping analysis of (18) F-FDG PET

BACKGROUND AND PURPOSE

Reports describing functional neuroimaging techniques, such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT), in sporadic Creutzfeldt-Jakob disease (sCJD) have consistently suggested that these tools are sensitive for the identification of areas of hypoperfusion or hypometabolism, even in the early stages of sCJD. However, there are few reports on the use of [18F]fluoro-2-deoxy-D-glucose (FDG) PET in sCJD, and most of them are single case reports. Only two small cohort studies based on visual inspection or a region of interest method have been published to date. Using a statistical parametric mapping (SPM) analysis of (18) F-FDG PET, we investigated whether there are brain regions preferentially affected in sCJD.

METHODS

After controlling for age and gender, using SPM 2, we compared the glucose metabolism between (i) 11 patients with sCJD and 35 controls and (ii) the subset of five patients with the Heidenhain variant of sCJD and 35 controls.

RESULTS

The patients with sCJD showed decreased glucose metabolism in bilateral parietal, frontal and occipital cortices. The Heidenhain variant of sCJD showed glucose hypometabolism mainly in bilateral occipital areas.

CONCLUSIONS

Glucose hypometabolism in sCJD was detected in extensive cortical regions; however, it was not found in the basal ganglia or thalamus, which are frequently reported to be affected on diffusion-weighted images. The medial temporal area, which is possibly resistant to the prion deposits, was also less involved in sCJD.

Photo essay. MRI and positron emission tomography findings in Heidenhain variant Creutzfeldt-Jakob disease

The typical presentation of Heidenhain variant Creutzfeldt-Jakob disease (CJD) is a rapidly progressive visual loss in the setting of a relatively normal ophthalmologic examination. At presentation, patients with this uniformly fatal illness frequently demonstrate only minor cortical abnormalities on MRI. Here, we document the clinical presentation and imaging results of a patient with Heidenhain variant CJD in whom abnormalities on positron emission tomographic imaging were more evident than changes on MRI. These changes were present in striate cortex and visual association areas, providing clinical-anatomical correlation with our patient's visual deficits. Nuclear imaging provides a considerably more sensitive measure of neural dysfunction early in the course of this disease.

MRI and FDG PET/CT findings in a case of probable Heidenhain variant Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) is a neurodegenerative disease caused by the accumulation of a pathogenic isoform of a prion protein in neurons that is responsible for subacute dementia. The Heidenhain variant is an atypical form of CJD in which visual signs are predominant. This is a report of the case of a 65-year-old man with probable CJD of the Heidenhain variant, with topographical concordance between findings on magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (FDG) photopenic areas on positron emission tomography (PET)/computed tomography (CT) for cortical parietooccipital lesions.

Alexia without agraphia in Creutzfeldt–Jakob disease

Progressive dementia uncommonly presents with focal deficits referable to posterior cortical dysfunction. We describe a 62 year-old man who presented with progressive visual disturbance in whom detailed cognitive testing documented alexia without agraphia. The only finding from diagnostic investigations was hypoperfusion of the posterior left temporoparietal region on brain SPECT scan. He rapidly progressed and Creutzfeldt-Jakob disease (CJD) was confirmed at autopsy. Although reading disorders may develop in association with posterior cortical atrophy due to CJD, this is the first reported autopsy-confirmed case presenting as alexia without agraphia.

The imaging appearance of Creutzfeldt-Jakob disease caused by the E200K mutation

The E200K mutation on chromosome 20 can cause familial Creutzfeldt-Jakob disease (CJD). Patients with this mutation are clinically similar to those with sporadic CJD, but their imaging features are not well documented. We report here the quantitative and qualitative evaluation of the magnetic resonance (MR) imaging characteristics of this unique group of patients using three-dimensional spoiled gradient recalled (SPGR) echo images, diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) measurements, MR spectroscopy and a fluid-attenuated inversion recovery (FLAIR) sequence. The SPGR and ADC data were analyzed with SPM99. ANCOVA and regression models were used for a region-of-interest (ROI) analysis of ADC and metabolic ratios. CJD patients had a decreased fraction of gray matter and an increased fraction of cerebrospinal fluid (P=.001) in the cortex and cerebellum and increased ADC values in the cortex (P<.001). Focal decreases of ADC were found in the putamen via ROI analysis (548+/-83 vs. 709+/-9 microm(2)/s, P=.02). N-acetyl aspartate (NAA) was generally reduced, with the NAA/Cho ratio lowest in the cingulate gyrus. Qualitative assessment revealed hyperintensities on FLAIR, DWI or both in the putamen (three out of four patients), caudate (three out of four patients) and thalamus. These results provide a framework for future study of patients with genetically defined familial CJD.

Asymmetric cortical high signal on diffusion weighted-MRI in a case of Creutzfeldt-Jakob disease

High signal in the cerebral cortex and/or basal ganglia on diffusion-weighted magnetic resonance imaging (DW-MRI) has been described as a good diagnostic marker for sporadic Creutzfeldt-Jakob disease (sCJD). We report a case of sCJD with atypical clinical evolution and unusual DW-MRI findings. A 53-year-old man was seen with a 2-year history of a rapidly progressive dementia and cerebellar ataxia. Cerebrospinal fluid analysis, including the test for 14-3-3 protein, was normal. EEG did not show periodic activity. However, DW-MRI showed gyriform hyperintensity involving practically the entire cortical ribbon of the left hemisphere, whilst being limited to the posterior cingulate gyrus in the right hemisphere. DNA analysis showed no mutations or insertions in the prion protein gene, and homozigozity for methionine in codon 129. A subsequent brain biopsy confirmed the diagnosis of CJD. Thus, high signal on DW-MRI may be limited to the cerebral cortex and may present a very asymmetric distribution in sCJD.

Forme de Heidenhain de la maladie de Creutzfeldt-Jakob

INTRODUCTION

Creutzfeldt-Jakob's disease has various anatomoclinical presentations including a rare form with preponderant visual signs described by Heidenhain. In this form, the visual symptoms may be isolated for a few weeks, leading to multiple ophthalmological examinations.

OBSERVATION

We report the case of a 75-year-old woman who developed isolated visual disorders which rapidly increased over a period of two months. Addition of neurological symptoms, abnormalities of EEG and positivity of 14-3-3 protein led to the diagnosis of Creutzfeldt-Jakob's disease. The patient died 14 months after the first neuroophthalmologic signs. The diagnosis was established by post-mortem examination and immuno-electrophoretic demonstration of type 1 prion protein.

CONCLUSION

Heidenhain's form of Creutzfeldt-Jakob's disease highlights the importance of general rules for prevention of iatrogenic hazard during ophthalmological examinations.

Subacute spongiform encephalopathies

Subacute spongiform encephalopathies are rare fatal diseases that affect the central nervous system, which is thought to be caused by prions, characterized clinically by a rapid progressive dementing course, along with generalized myoclonus. The prototype of these conditions in humans is Creutzfeldt-Jakob Disease (CJD). Although the final diagnosis depends on neuropathological examination, the presence of periodic sharp wave complexes on EEG and of the neuron-specific enolase, tau protein, S-100, and of the 14-3-3 protein in the cerebrospinal fluid, make the diagnosis of probable CJD. However, as these criteria are not completely accurate and the early diagnosis is extremely difficult, much interest has been focused recently on imaging methods. With the advent of diffusion-weighted imaging, MRI has shown high sensitivity and specificity, therefore being considered a useful method for the early diagnosis of this entity.