An autopsied case report of spastic paraplegia with thin corpus callosum carrying a novel mutation in the SPG11 gene: widespread degeneration with eosinophilic inclusions

Background The detailed neuropathological features of patients with autosomal recessive hereditary spastic paraplegia with a thin corpus callosum (TCC) and SPG11 mutations are poorly understood, as only a few autopsies have been reported. Herein, we describe the clinicopathological findings of a patient with this disease who received long-term care at our medical facility. Case presentation A Japanese man exhibited a mild developmental delay in early childhood and intellectual disability, followed by the appearance of a spastic gait by age 13. At the age of 25 years, he became bedridden and needed a ventilator. Genetic analysis revealed a homozygous splice site variant in the SPG11 gene (c. 4162–2A > G) after the provision of genetic counselling and acquisition of informed consent from his parents. He died of pneumonia at the age of 44. His brain weighed 967 g and was characterized by a TCC, and his spinal cord was flattened. Microscopically, degeneration was observed in the posterior spinocerebellar tract, the gracile fasciculus, and the posterior column in addition to the corticospinal tract. Marked neuronal loss and gliosis were observed in the anterior horn, Clarke’s column, and hypoglossal and facial nuclei. Various types of neurons, in addition to motor neurons, showed coarse eosinophilic granules that were immunoreactive for p62. The loss of pigmented neurons with gliosis was apparent in both the substantia nigra and locus coeruleus. Lateral geniculate body degeneration was a characteristic feature of this patient. Furthermore, peripheral Lewy body-related α-synucleinopathy and scattered α-synuclein–immunoreactive neurites in the locus coeruleus and reticular formation of the brainstem were observed. Conclusions In patients with hereditary spastic paraplegia with SPG11 mutations, a variety of clinical phenotypes develop due to widespread lesions containing p62-immunoreactive neuronal cytoplasmic inclusions. We herein report the lateral geniculate body as another degenerative site related to SPG11-related pathologies that should be studied in future investigations.

Diffusion Restriction in the Optic Radiation of Term Neonates With Hypoxic-Ischemic Encephalopathy Demonstrated by Magnetic Resonance Imaging (MRI)

Objective: There has been no previous report of diffusion restriction in the optic radiation of term neonates with hypoxic-ischemic encephalopathy. Here, using diffusion-weighted magnetic resonance imaging (MRI), we assessed diffusion restriction in the optic radiation within the first 2 weeks of life and estimated signal changes and the apparent diffusion coefficient in the optic radiation and lateral geniculate body using T1-weighted MRI. Materials and Methods: Forty-five term neonates with hypoxic-ischemic encephalopathy underwent MRI twice during the first 2 weeks of life. Diffusion-weighted imaging and apparent diffusion coefficient were used to evaluate the presence of diffusion restriction in the optic radiation and lateral geniculate body. Apparent diffusion coefficient and T1 signal changes in the optic radiation and lateral geniculate body were also compared with those in 11 control neonates showing a normal pattern on MRI. Results: Diffusion restriction in the optic radiation was observed in 29% (13/45) of the hypoxic-ischemic encephalopathy neonates at a median age of 3.5 days (range: 1-9 days). The apparent diffusion coefficient in the optic radiation of affected neonates was significantly reduced in comparison with the controls. In all neonates with optic radiation involvement, increased T1 signal intensity was observed in the optic radiation in the second week, and was also evident in in lateral geniculate body in 8 of those neonates. Conclusion: Diffusion restriction in the optic radiation is not rare among term neonates with hypoxic-ischemic encephalopathy, being visualized by diffusion-weighted imaging in the first week of life and also high-intensity T1 signal changes in the second week. This diffusion restriction in the optic radiation might be due to transsynaptic neuronal degeneration.

Loss of Vision Due to Bilateral Lateral Geniculate Body Infarction after Traumatic Brain Injury

In TBI patients, LPG infarction as a consequence of descending transtentorial herniation should be considered as a possible etiology of bilateral blindness.

Dyslexia & the Pons

Introduction Dyslexia is a learning disorder. It is centered on the Pons. It affects between 5 to 17% of the population. The Pons is where the balance takes place. People with Dyslexia have trouble with balance. The Pons is also central to the sub consciousness, which is tied in with REM sleep. The sleep equation therefore applies. The Pons is involved in communication by facial expression. People with Dyslexia is a communication disorder since those with it have trouble linking visual and hearing senses. The Cranial Nerve VIII, Vestibular Nerve, responsible for hearing comes out of the Pons. The tracts for sight and hearing pass through the Lateral Geniculate Body (LGB) and the Medical Geniculate Body. (MGB) which are located on the anterior of the Thalamus. Reading and wringing, which is a problem with Dyslexia, involves both seeing and hearing. We translate visual signal to vocal words and writing. Dyslexia also have trouble with writing letters. They do letter backwards. The is an orientation problem. It may have to do with the left hemisphere which usually is responsible for language (Broca’s and Wernicke’s Areas). The Pons too is responsible for communication, especially the nonverbal facial recognition.

Deep Learning-Supported Cytoarchitectonic Mapping of the Human Lateral Geniculate Body in the BigBrain

The human lateral geniculate body (LGB) with its six sickle shaped layers (lam) represents the principal thalamic relay nucleus for the visual system. Cytoarchitectonic analysis serves as the groundtruth for multimodal approaches and studies exploring its function. This technique, however, requires experienced knowledge about human neuroanatomy and is costly in terms of time. Here we mapped the six layers of the LGB manually in serial, histological sections of the BigBrain, a high-resolution model of the human brain, whereby their extent was manually labeled in every 30th section in both hemispheres. These maps were then used to train a deep learning algorithm in order to predict the borders on sections in-between these sections. These delineations needed to be performed in 1 µm scans of the tissue sections, for which no exact cross-section alignment is available. Due to the size and number of analyzed sections, this requires to employ high-performance computing. Based on the serial section delineations, high-resolution 3D reconstruction was performed at 20 µm isotropic resolution of the BigBrain model. The 3D reconstruction shows the shape of the human LGB and its sublayers for the first time at cellular precision. It represents a use case to study other complex structures, to visualize their shape and relationship to neighboring structures. Finally, our results could provide reference data of the LGB for modeling and simulation to investigate the dynamics of signal transduction in the visual system.

Expression of brain-derived neurotrophic factor in the lateral geniculate body of monocular form deprivation amblyopic kittens

Purpose: The present study compared the expression of brain-derived neurotrophic factor (BDNF) in the lateral geniculate body between form deprivation amblyopia kittens and normal kittens to examine the significance of BDNF in the lateral geniculate body in the pathogenesis of amblyopia. Methods: Twenty kittens were divided into control group ( n = 10) and deprivation group ( n = 10). A black opaque eye mask was placed to cover the right eye of the deprivation group. Pattern visual-evoked potentials (PVEPs) were detected weekly in all kittens .After the kittens in the deprivation group developed monocular amblyopia, the lateral geniculate bodies of all kittens were removed. The expression of BDNF in the lateral geniculate body of the two groups was compared by immunohistochemistry and Western blotting. Results: The latency of the P100 wave in the right eye of the deprivation group was longer than that of the left eye and that of the right eye of the control group ( p < 0.05), and the amplitude decreased ( p < 0.05). The number and average optical density of BDNF-positive cells in the deprivation group were lower than those in the control group ( p < 0.05), and the expression of BDNF in the deprivation group was lower than that in the control group ( p < 0.05). Conclusions: The expression of BDNF in the lateral geniculate body of the amblyopic kittens decreased, and the decrease in BDNF promoted the development of amblyopia. These results demonstrate that BDNF in the lateral geniculate body plays an important role in visual development.

Diffusion Tensor Imaging Studies on Recovery of Injured Optic Radiation: A Minireview

The optic radiation (OR) is a visual neural fiber pathway for the transfer of visual information from the lateral geniculate body of the thalamus to the primary visual cortex. To demonstrate the recovery of an OR injury, quantification and visualization of changes to the injured OR are necessary. Diffusion tensor imaging (DTI) allows determination of the state of an OR by assessing the obtained DTI parameters. In particular, diffusion tensor tractography (DTT), which is derived from DTI data, allows three-dimensional visualization of the OR. Thus, recovery of an injured OR can be demonstrated by examining changes in DTI parameters and/or configuration on follow-up DTI scans or via DTT of the injured OR. Herein, we review nine DTI-based studies that demonstrated recovery of OR injuries. The results reported in these studies suggest that an OR injury has a potential for recovery. Moreover, the results of these studies can form a basis for elucidating the recovery mechanisms of injured OR. These studies have suggested two recovery mechanisms for OR injury: recovery via the original OR pathway or via the transcallosal fibers of the corpus callosum. However, only nine studies on this topic have been conducted to date and six of those nine studies were case reports. Therefore, further studies involving larger numbers of subjects and reporting precise evaluations of changes in OR injury during recovery are warranted.

Histochemical assessment of Moringa – oleifera oil and walnut oil on cadmium induced lateral geniculate body damage in developing male Wistar rats (Rattus novergiccus)

The brain is vulnerable to oxidative damage due to its high oxygen consumption. This Study investigate the effects of cadmium on the lateral geniculate body of developing male wistar rats and ameliorative potential of Moringa oleifera seed oil and walnut oil extracts. Seven groups of five animals each were used in this experiment. Group A received 3ml of 0.9% normal saline; group B received 2.5mg/kg bw of 3CdSO4.8H2O, group C received 5mg/kg bw vitamin C & 6mg/kg bw vitamin E, group D received 5mg/kg bw vitamin C & 6mg/kg bw vitamin E + 2.5mg/kg bw Cd, group E received 2.5mg/kg bw Cd + 4mg/kg bw Moringa oleifera oil, group F received 2.5mg/kg bw Cd + 4mg/kg bw walnut oil, while group G received 2.5mg/kg bw Cd + 2mg/kg bw walnut + 2mg/kg bw Moringa oleifera oil concomitantly for 3weeks. Parameter tested includes LDH, G6PD in brain tissues, SOD and GPx enzymes in brain homogenates and serum and cresyl fast violet stain in the brain tissues. Cd administration significantly increased SOD, GPx, LDH and decreased G6PD level in brain tissue and decreased their activity in serum when compared with Group A control rats. There was marked reduction and lost in the distribution of nissl substances of the studied tissues of Cd administered animals. However, administration of vitamin C & E, walnut and Moringa oleifera oil restored damaged tissues. Walnut and Moringa oleifera seed oil therefore attenuated the oxidative damage and morphological changes induced by cadmium in the lateral geniculate body of the brain of the young male wistar rats.Key Words: Lateral geniculate body, Antioxidant, Histochemical, Cadmium, Oxidative Damage