scholarly journals Correlation of a new hydrodynamic index with other effective indexes in Chiari I malformation patients with different associations

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Seifollah Gholampour ◽  
Hanie Gholampour
Keyword(s):  
Cfd Simulation ◽  
Clinical Symptoms ◽  
Fluid Dynamic ◽  
Chiari I Malformation ◽  
The Other ◽  
Type I ◽  
Csf Pressure ◽  
Chiari Type I Malformation ◽  
Headache Symptom ◽  
Relationship Of

Abstract This study aimed to find a new CSF hydrodynamic index to assess Chiari type I malformation (CM-I) patients’ conditions and examine the relationship of this new index with morphometric and volumetric changes in these patients and their clinical symptoms. To this end, 58 CM-I patients in four groups and 20 healthy subjects underwent PC-MRI. Ten morphometric and three volumetric parameters were calculated. The CSF hydrodynamic parameters were also analyzed through computational fluid dynamic (CFD) simulation. The maximum CSF pressure was identified as a new hydrodynamic parameter to assess the CM-I patients’ conditions. This parameter was similar in patients with the same symptoms regardless of the group to which they belonged. The result showed a weak correlation between the maximum CSF pressure and the morphometric parameters in the patients. Among the volumetric parameters, PCF volume had the highest correlation with the maximum CSF pressure, which its value being higher in patients with CM-I/SM/scoliosis (R2 = 65.6%, P = 0.0022) than in the other patients. PCF volume was the more relevant volumetric parameter to assess the patients’ symptoms. The values of PCF volume were greater in patients that headache symptom was more obvious than other symptoms, as compared to the other patients.

Chiari Type I Malformation Presenting as Hemifacial Spasm: Case Report

Neurosurgery ◽  
2005 ◽  
Vol 57 (2) ◽  
pp. E371-E371 ◽  
Author(s):  
Mustafa Efkan Colpan ◽  
Zeki Sekerci
Keyword(s):  
Facial Nerve ◽  
Posterior Fossa ◽  
Hemifacial Spasm ◽  
Chiari I Malformation ◽  
Posterior Fossa Decompression ◽  
Type I ◽  
Chiari Type I Malformation ◽  
Downward Displacement ◽  
Facial Spasm ◽  
Chiari I

ABSTRACT OBJECTIVE AND IMPORTANCE: We report on a patient with a Chiari I malformation presenting with right hemifacial spasm. Clinicians should consider the downward displacement of the hindbrain as a rare cause of hemifacial spasm in Chiari I malformation. CLINICAL PRESENTATION: An 18-year-old man was admitted with right hemifacial spasm. The results of the neurological examination were normal except for the facial spasm. Magnetic resonance imaging demonstrated a Chiari I malformation without syringomyelia. After surgery, the hemifacial spasm completely resolved. INTERVENTION: Posterior fossa decompression, C1 laminectomy, and duraplasty were performed. CONCLUSION: The hemifacial spasm could be attributed to compression and/or traction of the facial nerve because of downward displacement of the hindbrain in Chiari I malformation. Compression and/or traction might create irritation of the facial nerve that causes hemifacial spasm. Resolution of the hemifacial spasm after posterior fossa decompression could explain the facial nerve irritation in Chiari I malformation. Clinicians should consider Chiari malformation as a cause of hemifacial spasm and posterior fossa decompression as a potential treatment.

scholarly journals The Capacity of Periodontal Gel to Occupy the Spaces Inside the Periodontal Pockets Using Computational Fluid Dynamic

2019 ◽  
Vol 8 (1) ◽  
pp. 1
Author(s):  
Luca Levrini ◽  
Luigi Paracchini ◽  
Maria Giulia Nosotti
Keyword(s):  
Rheological Properties ◽  
Computational Fluid Dynamic ◽  
Type I Collagen ◽  
Saline Solution ◽  
Fluid Dynamic ◽  
The Other ◽  
Periodontal Pocket ◽  
Type I ◽  
Cat Scan ◽  
Different Types

The aim of the current work is to demonstrate the capacity of a new periodontal gel to occupy the spaces inside the periodontal pockets through Computational Fluid Dynamic (CFD). The test gel consists of two resorbable medical grade polymers (PEO, Poly Ethylen Oxide and HPMC, Hydroxy Propyl Metyl Cellulose), Type I Collagen, SAP (Vitamin C), and PBS (Saline Solution), while the control gel is 14% doxyclin controlled release gel, which is used for treating periodontal pockets with probing ≥5 mm after scaling and root plaining. The study examined the fluid dynamic analysis (Computational Fluid Dynamic—CFD) of two different gels, used in dentistry to treat periodontitis, in relation to both the geometry of the periodontal pocket and the function of two different types of needles that are used to distribute the preparation. The periodontal pocket was determined by reading DICOM images taken from the patient’s CAT scan. The results show that the H42® gel comes out uniformly compared to the other gel. Moreover, it is possible to observe how the rheological properties of the gel allow the fluid to spread evenly within the periodontal pocket in relation to the geometry of the needle. In particular, H42® gel exits in a constant way both from the first and the second exit. In fact, it was observed that by changing the geometry of the needle or the type of periodontal gel, the distribution of the gel inside the pocket was no longer homogeneous. Thus, having the correct rheological properties and correct needle geometries both speeds up the gel and optimizes the pressure distribution. Currently, the literature is still lacking, therefore further studies will be needed to confirm these results.

Sleep Apnea and the Chiari I Malformation: Case Report

Neurosurgery ◽  
1988 ◽  
Vol 23 (4) ◽  
pp. 508-510 ◽  
Author(s):  
Philip Levitt ◽  
Martin A. Cohn
Keyword(s):  
Case Report ◽  
Sleep Apnea ◽  
Chiari I Malformation ◽  
Type I ◽  
Ambulatory Patient ◽  
Chiari Type ◽  
Chiari Type I Malformation ◽  
Chiari I ◽  
Chiari Type I

Abstract The authors report the case of an ambulatory patient who presented with sleep apnea episodes of the central and obstructive types and an associated Chiari Type I malformation. The central episodes stopped and the obstructive episodes decreased markedly after decompression. The improvement in the so-called obstructive episodes was unexpected and indicates that they may have been on a central basis.

scholarly journals Syringomyelia intermittens: highlighting the complex pathophysiology of syringomyelia. Illustrative case

2021 ◽  
Vol 2 (11) ◽  
Author(s):  
Jorn Van Der Veken ◽  
Marguerite Harding ◽  
Saba Hatami ◽  
Marc Agzarian ◽  
Nick Vrodos
Keyword(s):  
Clinical Symptoms ◽  
Incidental Finding ◽  
Foramen Magnum ◽  
Illustrative Case ◽  
Cervical Canal ◽  
Type I ◽  
Natural Evolution ◽  
Chiari Type I Malformation ◽  
Asymptomatic Patients ◽  
History Of

BACKGROUND Chiari Type I malformation (CM1) is a disorder recognized by caudal displacement of the cerebellar tonsils through the foramen magnum and into the cervical canal. Syringomyelia is frequently found in patients with CM1, but the pathophysiology of syringomyelia remains an enigma. As a general consensus, symptomatic patients should be treated and asymptomatic patients without a syrinx should not be treated. Mildly symptomatic patients or asymptomatic patients with a syrinx, on the other hand, pose a more challenging dilemma, as the natural evolution is uncertain. For many surgeons, the presence of a syrinx is an indication to offer surgery even if the patient is asymptomatic or mildly symptomatic. OBSERVATIONS The authors describe an illustrative case of a 31-year-old female with an incidental finding of a CM1 malformation and cervical syrinx in 2013. Conservative management was advocated as the patient was asymptomatic. Monitoring of the syrinx over a course of 8 years showed resolution, followed by reappearance and finally a complete resolution in 2021. A review of the literature and the possible pathophysiology is discussed. LESSONS The unusual course of this patient highlights the importance of guiding treatment by clinical symptoms, not radiological findings. Furthermore it reflects the complexity of the pathophysiology and the uncertain natural history of syringomyelia.

scholarly journals Chiari Type I malformation yielded to the diagnosis of Crouzon syndrome

2014 ◽  
Vol 5 (01) ◽  
pp. 81-83 ◽  
Author(s):  
Aydin Canpolat ◽  
Mehmet Osman Akçakaya ◽  
Emre Altunrende ◽  
Harun Mehmet Özlü ◽  
Hakan Duman ◽  
...  
Keyword(s):  
Posterior Fossa ◽  
Clinical Symptoms ◽  
Careful Examination ◽  
Posterior Fossa Decompression ◽  
Type I ◽  
Crouzon Syndrome ◽  
Late Adolescent ◽  
Chiari Malformation Type I ◽  
Chiari Type I Malformation ◽  
Syndromic Craniosynostosis

ABSTRACTChiari malformation Type I (CM-I) related to syndromic craniosynostosis in pediatric patients has been well-studied. The surgical management consists of cranial vault remodeling with or without posterior fossa decompression. There were also cases, in whom CM-I was diagnosed prior to the craniosynostosis in early childhood. We present a 16-year-old boy who admitted with symptoms related to CM-I. With careful examination and further genetic investigations, a diagnosis of Crouzon syndrome was made, of which the patient and his family was unaware before. The patient underwent surgery for posterior fossa decompression and followed-up for Crouzon’s syndrome. To our knowledge, this is the only case report indicating a late adolescent diagnosis of Crouzon syndrome through clinical symptoms of an associated CM-I.

scholarly journals Outcome of Posterior Fossa Decompression for Chiari Type I Malformation with Syringomyelia

2019 ◽  
Vol 16 (1) ◽  
pp. 35-38
Author(s):  
Sagar Koirala ◽  
Suresh Bishokarma ◽  
Dinesh Nath Gongal ◽  
Henry Thomas Marsh
Keyword(s):  
Posterior Fossa ◽  
Chiari I Malformation ◽  
Posterior Fossa Decompression ◽  
Type I ◽  
Chiari Type ◽  
Chiari Type I Malformation ◽  
Tertiary Center ◽  
Clinical And Radiological Outcome ◽  
Chiari I ◽  
Chiari Type I

There are various treatment approaches for treating Chiari type I malformation with syringomyelia. Despite various choices, consensus for one particular approach is lacking. The objective of this study is to find out the clinical and radiological outcome of standard posterior fossa decompression incorporating removal of C1 arch with lax duroplasty in such cases. A retrospective study based on data acquired from a single tertiary center were analyzed. All cases who underwent posterior fossa decompression incorporating removal of C1 arch with lax duroplasty over a period of five years were included and their clinical and radiological progress were recorded during OPD follow up at 6 months. Out of 21 cases, occipital headache with nape of neck pain was the predominant complaint accounting to 71% followed by sensory symptoms and motor weakness, 61% and 33% respectively. Pain resolved in 93%, weakness in 71% and sensory symptoms in 69% of the cases. Only one patient developed hydrocephalus requiring shunting. Radiological improvement of syringomyelia were documented in 76.1% of the patients. There was no mortality. Posterior fossa decompression incorporating removal of C1 arch and lax duroplasty is a safe approach with good outcome in patients with Chiari I malformation with syringomyelia.

scholarly journals Severe Cerebellar Degeneration and Chiari I Malformation - Speculative pathophysiology based on a systematic review

2020 ◽  
Vol 66 (3) ◽  
pp. 375-379
Author(s):  
Andrei Fernandes Joaquim
Keyword(s):  
Cerebellar Atrophy ◽  
Chiari I Malformation ◽  
Venous Hypertension ◽  
Cerebellar Degeneration ◽  
Posterior Fossa Decompression ◽  
Type I ◽  
Small Vessels ◽  
Chiari Type I Malformation ◽  
Pubmed Database ◽  
Key Terms

SUMMARY BACKGROUND Symptomatic Chiari Type I Malformation (CM) is treated with posterior fossa decompression with or without duroplasty. We have noticed some cases with concomitant severe cerebellar ataxia due to cerebellar atrophy. The aim of this study is to review the literature of CM associated with severe cerebellar atrophy and discuss its potential physiopathology. METHODS A systematic literature review in the Pubmed Database was performed using the following key-terms: “cerebellar atrophy Chiari”, and “cerebellar degeneration Chiari”. Articles reporting the presence of cerebellar degeneration/atrophy associated with CM were included. RESULTS We found only six studies directly discussing the association of cerebellar atrophy with CM, with a total of seven cases. We added one case of our own practice for additional discussion. Only speculative causes were described to justify cerebellar atrophy. The potential causes of cerebellar atrophy were diffuse cerebellar ischemia from chronic compression of small vessels (the most mentioned speculative cause), chronic raised intracranial pressure due to CSF block, chronic venous hypertension, and association with platybasia with ventral compression of the brainstem resulting in injury of the inferior olivary nuclei leading to mutual trophic effects in the cerebellum. Additionally, it is not impossible to rule out a degenerative cause for cerebellar atrophy without a causative reason. CONCLUSIONS Severe cerebellar atrophy is found in some patients with CM. Although chronic ischemia due to compression is the most presumed cause, other etiologies were proposed. The real reasons for cerebellar degeneration are not known. Further studies are necessary.

scholarly journals Syringomyelia with Chiari I Malformation Presenting as Hip Charcot Arthropathy: A Case Report and Literature Review

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Roya Memarpour ◽  
Basheer Tashtoush ◽  
Lydia Issac ◽  
Fernando Gonzalez-Ibarra
Keyword(s):  
Articular Surface ◽  
Imaging Study ◽  
Chiari I Malformation ◽  
Type I ◽  
Charcot Arthropathy ◽  
Charcot Neuroarthropathy ◽  
Chiari Type I Malformation ◽  
Upper And Lower Extremities ◽  
Surface Destruction ◽  
The Right

Neuroarthropathy (neuropathic osteoarthropathy), also known as Charcot joint, is a condition characterized by a progressive articular surface destruction in the setting of impaired nociceptive and proprioceptive innervation of the involved joint. It is seen most commonly in the foot and ankle secondary to peripheral neuropathy associated with diabetes mellitus. Cases of hip (Charcot) neuroarthropathy are rare and almost exclusively reported in patients with neurosyphilis (tabes dorsalis). We report a case of a 36-year-old man who presented to the emergency department complaining of right hip pain. On physical examination, pain and thermal sensory deficits were noted in the upper torso with a cape-like distribution, as well as signs of an upper motor neuron lesion in the left upper and lower extremities. A magnetic resonance imaging study (MRI) of the right hip showed evidence of early articular surface destruction and periarticular edema consistent with hip Charcot arthropathy. An MRI of the spine revealed an Arnold-Chiari type I malformation with extensive syringohydromyelia of the cervical and thoracic spine.

scholarly journals Headache precipitated by Valsalva maneuvers in patients with congenital Chiari I malformation

2010 ◽  
Vol 68 (3) ◽  
pp. 406-409 ◽  
Author(s):  
Hugo André de Lima Martins ◽  
Valdenilson Ribeiro Ribas ◽  
Murilo Duarte Costa Lima ◽  
Daniella Araújo de Oliveira ◽  
Marcelo Tavares Viana ◽  
...  
Keyword(s):  
Sexual Activity ◽  
Chiari I Malformation ◽  
Frontal Region ◽  
Type I ◽  
Precipitating Factors ◽  
Chiari Type ◽  
Chiari Type I Malformation ◽  
Chiari I ◽  
Headache Pain ◽  
Chiari Type I

The objective of this study was to characterize the headache precipitated by Valsalva maneuvers associated with Chiari type I malformation (CM-1). Nineteen patients were evaluated, with ages ranging from 30 to 75 years. Ten of them presented headache. Pain was more prevalent in the occipital (80%) and frontal region (60%). The headaches were of significantly shorter duration in the women compared with the men. The frequency of headache crises was relatively high. All patients with Valsalva-related headache suffered from at least one episode per month. The most prevalent precipitating factors were coughing, which is well described in the literature, and sexual activity, which only now is recognized as an event associated with CM-1.

scholarly journals Impeller Optimization in Crossflow Hydraulic Turbines

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 313
Author(s):  
Marco Sinagra ◽  
Calogero Picone ◽  
Costanza Aricò ◽  
Antonio Pantano ◽  
Tullio Tucciarelli ◽  
...  
Keyword(s):  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Structural Safety ◽  
3D Fem ◽  
Good Efficiency ◽  
Standard Material ◽  
Variable Head ◽  
Hydraulic Turbines ◽  
Constructive Simplicity ◽  
Mechanical Optimization

Crossflow turbines represent a valuable choice for energy recovery in aqueducts, due to their constructive simplicity and good efficiency under variable head jump conditions. Several experimental and numerical studies concerning the optimal design of crossflow hydraulic turbines have already been proposed, but all of them assume that structural safety is fully compatible with the sought after geometry. We show first, with reference to a specific study case, that the geometry of the most efficient impeller would lead shortly, using blades with a traditional circular profile made with standard material, to their mechanical failure. A methodology for fully coupled fluid dynamic and mechanical optimization of the blade cross-section is then proposed. The methodology assumes a linear variation of the curvature of the blade external surface, along with an iterative use of two-dimensional (2D) computational fluid dynamic (CFD) and 3D structural finite element method (FEM) simulations. The proposed methodology was applied to the design of a power recovery system (PRS) turbine already installed in an operating water transport network and was finally validated with a fully 3D CFD simulation coupled with a 3D FEM structural analysis of the entire impeller.

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