Constrictive Myelopathy in An Old Giant Dog

In pugs, West Highland white terriers and other small breeds, congenital or acquired malformations/deviations of the spine are commonly reported, resulting, amongst other complications, in chronic meningeal compression and fibrosis, and interference with cerebrospinal fluid flow into the sub-arachnoid space. This leads to constrictive myelopathy (CM) which involves the constriction and consequent reduced diameter of the spinal cord accompanied by parenchymal damage (mostly gliosis). A11-year-old giant mixed breed male dog presented with ataxia in the hindlimbs, paresis, reduced proprioception, and normal reflexes. Neurolocalization was to the thoracolumbar spinal cord (T3-L3). Myelographic computed tomography and magnetic resonance imaging (MRI) of this tract showed spondylosis, multiple disc protrusions with mild cord compression, and reduced spinal cord diameter. Genetic test for SOD1 mutations performed to evaluate predisposition to degenerative myelopathy negative results; although poorly compressive, the symptoms were attributed to multiple disc protrusions, leading to spinal cord atrophy. The dog underwent physiotherapy and 23 months later, was more ataxic and paretic however still ambulatory; repeated MRI confirmed the previous findings, however, the onset of concomitant megacolon and a chronic kidney failure, induced the owner to euthanasia. Histopathological assessment indicated diffused remodeling of the meninges with progressive constriction of the spinal cord of concomitant megacolon and a chronic kidney failure, induced the owner to euthanasia. Histopathological assessment indicated diffused remodeling of the meninges with progressive constriction of the spinal cord. Altered distribution of the mechanical forces among the meningeal layers with stiffening of the ventral pachymeninges, probably caused by the disc protrusions, was considered the most likely trigger. To our knowledge, this is the first case reporting clinical, MRI and histological findings resembling an acquired constrictive myelopathy in a large-breed dog.

Neural Network Segmentation Algorithm-Based Magnetic Resonance Imaging to Explore the Relationship between Cerebrospinal Fluid Flow with Communicating Hydrocephalus after Decompressive Craniectomy for Craniocerebral Injury

This study aimed to explore the application value of magnetic resonance imaging optimized by neural network segmentation algorithm in analyzing the relationship between cerebrospinal fluid changes after decompressive craniectomy and the occurrence of communicating hydrocephalus. 100 patients with craniocerebral injury undergoing decompressive craniectomy in hospital were selected as research subjects. The collected MRI images were processed using the OTSU algorithm, the cerebrospinal fluid flow rate was calculated based on the observation results, and the MRI based on the neural network segmentation algorithm was used to analyze the relationship between the occurrence of communicating hydrocephalus with the cerebrospinal fluid flow after decompressive craniectomy for craniocerebral injury. Additionally, the dynamics of the flow of cerebrospinal fluid in the midbrain aqueduct was analyzed. After decompressive craniectomy for craniocerebral injury, of the 24 cases of cerebrospinal fluid accumulation, 23 cases had hydrocephalus; of the 55 cases of cerebrospinal fluid flow disorder, hydrocephalus occurred in 47 cases; and of the 21 cases of normal cerebrospinal fluid, no patients had hydrocephalus. For patients with communicating hydrocephalus, the cerebrospinal fluid flow at the aqueduct was obviously accelerated and the flow was increased. From this, the differential diagnosis of cerebrospinal fluid and communicating hydrocephalus can be further confirmed. The results showed that the third ventricle of the study group was significantly reduced, and the flow of cerebrospinal fluid was similar to that of normal people. It suggested that decompressive craniectomy can relieve communicating hydrocephalus. In patients with communicating hydrocephalus, the cerebrospinal fluid flow at the aqueduct was significantly accelerated, the flow amount was increased, and the blocked flow of cerebrospinal fluid can also lead to hydrocephalus, which further clarified the relationship between the occurrence of communicating hydrocephalus with the flow of cerebrospinal fluid. In short, the neural network segmentation algorithm-based magnetic resonance imaging demonstrated a good value in the analysis of craniocerebral injury, from which the doctor observed that the cerebrospinal fluid flow at the aqueduct was significantly accelerated. Its detection of brain complications after decompressive craniectomy was also effective.

Cerebrospinal fluid flow impairment in the patients with Chiari malformation: predictors of syringomyeliа cysts development and dynamics of postoperative regression

Background. Chiari malformation (CM) is a defect in the development of the central nervous system, manifested by the mismatch between the size of the posterior cranial fossa and the brain structures located in this area, and, as a consequence, by the descent of the cerebellar tonsils (CM type 1), usually with a caudal dislocation of the lower parts of the brainstem into the foramen magnum (CM type 1.5). As a result of cerebrospinal fluid (CSF) flow disorders, 60–90 % of patients with CM have syringomyelia. Materials and methods. A retrospective analysis was performed of clinical records of 24 patients with Chiari malformation types 1 and 1.5, who had undergone surgeries at the Uzhhorod Regional Clinical Center of Neurosurgery and Neurology from December 2006 to December 2017, during which suboccipital decompressive craniectomy, C1 laminectomy, duraplasty were performed. The average follow-up period after the surgery was 5 years. Results. In patients whose symptoms lasted for more than 3 years, the frequency of formation of the associated syrinxes was 57 %. The dynamics of the regression of CSF flow disorders in the postoperative period varies considerably depending on age. Conclusions. The risk of syrinx formation within the spinal cord is higher in patients with CM types 1 and 1.5 who have been ill for more than 3 years. Surgical treatment is an effective method used to correct CSF circulation disturbances. The cyst puncture is not obligatory during surgical interventions.

Pediatric and Adult Low-Grade Gliomas: Where Do the Differences Lie?

Two thirds of pediatric gliomas are classified as low-grade (LGG), while in adults only around 20% of gliomas are low-grade. However, these tumors do not only differ in their incidence but also in their location, behavior and, subsequently, treatment. Pediatric LGG constitute 65% of pilocytic astrocytomas, while in adults the most commonly found histology is diffuse low-grade glioma (WHO II), which mostly occurs in eloquent regions of the brain, while its pediatric counterpart is frequently found in the infratentorial compartment. The different tumor locations require different skillsets from neurosurgeons. In adult LGG, a common practice is awake surgery, which is rarely performed on children. On the other hand, pediatric neurosurgeons are more commonly confronted with infratentorial tumors causing hydrocephalus, which more often require endoscopic or shunt procedures to restore the cerebrospinal fluid flow. In adult and pediatric LGG surgery, gross total excision is the primary treatment strategy. Only tumor recurrences or progression warrant adjuvant therapy with either chemo- or radiotherapy. In pediatric LGG, MEK inhibitors have shown promising initial results in treating recurrent LGG and several ongoing trials are investigating their role and safety. Moreover, predisposition syndromes, such as neurofibromatosis or tuberous sclerosis complex, can increase the risk of developing LGG in children, while in adults, usually no tumor growth in these syndromes is observed. In this review, we discuss and compare the differences between pediatric and adult LGG, emphasizing that pediatric LGG should not be approached and managed in the same way as adult LCG.

Effect of Ventricular Elasticity Due to Congenital Hydrocephalus

Cerebrospinal fluid (CSF) is a symmetric flow transport that surrounds brain and central nervous system (CNS). Congenital hydrocephalusis is an asymmetric and unusual cerebrospinal fluid flow during fetal development. This dumping impact enhances the elasticity over the ventricle wall. Henceforth, compression change influences the force of brain tissues. This paper presents a mathematical model to establish the effects of ventricular elasticity through a porous channel. The current model is good enough for immediate use by a neurosurgeon. The mathematical model is likely to be a powerful tool for the better treatment of hydrocephalus and other brain biomechanics. The non-linear dimensionless governing equations are solved using a perturbation technique, and the outcome is portrayed graphically with the aid of MATLAB.

Progressive Myelopathy After Spine Surgery

A 69-year-old man with a progressive myelopathy for 2 years was referred for evaluation of suspected transverse myelitis. His medical history included discectomies, a severe episode of herpes simplex virus type 1 meningoencephalitis, and development of insidiously progressive numbness and weakness of his hands. Cervical spine magnetic resonance imaging showed 2 small, dural-based, gadolinium-enhancing lesions. Biopsy of these lesions showed only normal neural tissue. Subsequently, the dura was stripped away surgically from the lower cervical region, in an effort to remove these lesions. During the next year, a sensory level developed at about the level of the nipples (T4), along with a squeezing sensation on his trunk below. Imbalance and bilateral lower extremity weakness and numbness then developed. Magnetic resonance imaging showed a longitudinally extensive cord signal abnormality. The cause of the patient’s initial subjective hand numbness and weakness was indeterminate. The onset of severely progressive symptoms after surgical removal of those lesions and the reported stripping of dura made it likely that the progressive cord edema was due to chronic adhesive arachnoiditis. His prior meningoencephalitis was a potential additional risk factor for arachnoiditis. Computed tomography myelography showed a markedly abnormal spinal canal with scalloping of the cord contour, with delayed flow of contrast above C6-C7, consistent with arachnoid adhesions causing obstruction of normal cerebrospinal fluid flow. The patient was diagnosed with chronic adhesive arachnoiditis. A C4-C7 laminectomy and surgical lysis of the cord meningeal adhesions was performed, with subsequent intensive neurorehabilitation. Follow-up spinal cord magnetic resonance imaging 6 months after surgery showed improvement of the T2-signal abnormality but persistent myelomalacia and spinal cord atrophy. Adhesive arachnoiditis is an uncommon cause of progressive myelopathy resulting from an insult to the arachnoid meningeal layer, followed by inflammation and fibrosis. This process renders the arachnoid abnormally thick and adherent to the pia and dura mater. Abnormal adhesion of nerve roots or spinal cord to the dura produces neurologic impairment. Typical symptoms include back pain, paresthesias, lower limb weakness, and sensory loss. It is diagnosed clinically with supportive magnetic resonance imaging and computed tomography myelography findings.

Cerebrospinal fluid flow cytometry distinguishes psychosis spectrum disorders from differential diagnoses

Psychotic disorders are common and disabling mental conditions. The relative importance of immune-related mechanisms in psychotic disorders remains subject of debate. Here, we present a large-scale retrospective study of blood and cerebrospinal fluid (CSF) immune cell profiles of psychosis spectrum patients. We performed basic CSF analysis and multi-dimensional flow cytometry of CSF and blood cells from 59 patients with primary psychotic disorders (F20, F22, F23, and F25) in comparison to inflammatory (49 RRMS and 16 NMDARE patients) and non-inflammatory controls (52 IIH patients). We replicated the known expansion of monocytes in the blood of psychosis spectrum patients, that we identified to preferentially affect classical monocytes. In the CSF, we found a relative shift from lymphocytes to monocytes, increased protein levels, and evidence of blood–brain barrier disruption in psychosis. In fact, these CSF features confidently distinguished autoimmune encephalitis from psychosis despite similar (initial) clinical features. We then constructed machine learning models incorporating blood and CSF parameters and demonstrated their superior ability to differentiate psychosis from non-inflammatory controls compared to individual parameters. Multi-dimensional and multi-compartment immune cell signatures can thus support the diagnosis of psychosis spectrum disorders with the potential to accelerate diagnosis and initiation of therapy.

Interstitial and cerebrospinal fluid exchanging process revealed by phase alternate labeling with null recovery MRI

Purpose: To develop Phase Alternate LAbeling with Null recovery (PALAN) MRI methods for the quantification of interstitial to cerebrospinal fluid flow (ICF) and cerebrospinal to interstitial fluid flow (CIF) in the brain. Method: In both T1-PALAN and apparent diffusion coefficient (ADC)-PALAN MRI methods, the cerebrospinal fluid (CSF) signal was nulled, while the residual interstitial fluid (ISF) was labeled by alternating the phase of pulses. ICF was extracted from the difference between the recovery curves of CSF with and without labeling. Similarly, CIF was measured by the T2-PALAN MRI method by labeling CSF, which took advance of the significant T2 difference between CSF and parenchyma. Results: Both T1-PALAN and ADC-PALAN observed a rapid occurrence of ICF at 67±56 ms and 13±2 ms interstitial fluid transit times, respectively. ICF signal peaked at 1.5 s for both methods. ICF was 1153±270 ml/100ml/min with T1-PALAN in the third and lateral ventricles, which was higher than 891±60 ml/100ml/min obtained by ADC-PALAN. The results of the T2-PALAN suggested the ISF exchanging from ependymal layer to the parenchyma was extremely slow. Conclusion: The PALAN methods are suitable tools to study ISF and CSF flow kinetics in the brain.