Polymicrogyria refers to the abnormal development of the ridges and folds of the brain (gyri) during gestation. It is characterized by an excessive number (poly-) and small size (micro-) of the gyri in the cerebral cortex. Signs and symptoms of polymicrogyria depend on the extent of brain tissue affected, the regions of the brain affected, and whether it is unilateral or bilateral.
The signs and symptoms of polymicrogyria are variable; they depend on the degree and location of polymicrogyria. Infants with bilateral polymicrogyria have more severe symptoms compared to those that have unilateral involvement. Patients with generalized bilateral polymicrogyria present with various neurologic findings such as cognitive impairment, motor delay, refractory seizures, and/or quadriparesis    . Polymicrogyria has been associated with malformations such as schizencephaly, cerebellar hypoplasia , subcortical heterotopia , and periventricular nodular heterotopia .
While the symptoms of polymicrogyria vary, there are common clinical presentations based on the region of the brain affected. For example, patients with bilateral polymicrogyria of the frontal cortex often present with cognitive impairment, motor delay, epilepsy, and/or quadriparesis. Bilateral polymicrogyria of frontoparietal cortex results in significant cognitive impairment and motor delay, seizures, cerebellar problems, and/or dysconjugate gaze. Patients with bilateral perisylvian polymicrogyria present with cognitive impairment, epilepsy, pseudobulbar signs, arthrogryposis, and/or lower motor neuron disease. Bilateral polymicrogyria of the parasagittal parieto-occiptal region is associated with mental retardation and/or partial seizures.
Entire Body System
- Cerebral Palsy
Lyla was born with a rare brain disorder and has cerebral palsy. We all like marshmallows, dancing round the kitchen and hanging out at the park. [lylasangels.co.uk]
Cerebral palsy was seen in three (43%) of the patients, and all of them had left hemiparesis. Microcephaly, MMR, and speech delay were detected in one (14%) of the patients. [ncbi.nlm.nih.gov]
Secondary Diagnosis: Spastic Quadraplegic Cererbal Palsy Global Developmental Delay USEFUL RESOURCES AND LINKS Cerebral Palsy Organisations Therapy Tests and medical procedures [chiarasjourney.com]
About Cerebral Palsy Polymicrogyria is the condition which results in the diagnosis of cerebral palsy (CP). Ben has mixed tone CP. This means his trunk is loose (hypotonic) and his limbs are tight (hypertonic). [blessingsforbenjamin.com]
We compared various risk factors in cerebral palsy with and without perisylvian syndrome as shown in [Table 2]. [pediatricneurosciences.com]
- Developmental Disorder
Our results indicate that the presence of perisylvian polymicrogyria may not always result in the development of oropharyngoglossal dysfunction or dysarthria, although most patients tend to gradually show the onset of developmental disorders. [ncbi.nlm.nih.gov]
During the condition patients presented with epilepsy (61.7%), infantile cerebral palsy (47%), psychomotor/mental retardation (94.1%), pervasive developmental disorder (26.4%), behavioural disturbances (38.2%), neurosensory deficit (35.2%) and microcephaly [dialnet.unirioja.es]
His school performance was normal, and he has not shown any developmental abnormalities and pseudobulbar disorders. [intechopen.com]
Developmental language disorder associated with polymicrogyria. Neurology 2002 ; 59 : 245 –50. ↵ Miller SP, Shevell M, Rosenblatt B, Silver K, O’Gorman A, Andermann F. [doi.org]
Necrosis, calcification and meningeal inflammation associated with damage to the glia limitans are described [ 60 ]. [doi.org]
[…] autoimmune glomerulonephritis 慢性自己免疫性糸球体腎炎 3 Chronic cutaneous lupus erythematosus 慢性皮膚エリテマトーデス 3 Chronic fatigue syndrome 慢性疲労 症候群 3 Chronic gastritis 慢性胃炎 3 Chronic inflammatory demyelinating polyradiculoneuropathy 慢性炎症性脱髄性多発神経炎 3 Chronic lymphocytic inflammation [ikenori.com]
壊死性血管炎 9 Vena cava embolism 大静脈塞栓症 9 Vena cava thrombosis 大静脈血栓症 9 Venous intravasation 静脈内侵襲 9 Venous recanalisation 静脈の再疎通 9 Venous thrombosis 静脈血栓症 9 Venous thrombosis in pregnancy 妊娠中の静脈血栓症 9 Venous thrombosis limb 四肢静脈血栓症 9 Venous thrombosis neonatal [ikenori.com]
A 60-90 diopter esotropia was present and tracking was saccadic. Postnatal improvements in acuity and VEPs were seen in infants tested longitudinally. [iovs.arvojournals.org]
The main clinical features of BFPP include global developmental delay, dysconjugate gaze (esotropia), pyramidal and cerebellar signs, and seizures, which occur in 94% of patients and are mostly generalised. 26– 28 Although dysconjugate gaze is common [doi.org]
Nonconvulsive status epilepticus in epileptic encephalopathy with unilateral multilobar polymicrogyria has not been reported previously. [ncbi.nlm.nih.gov]
Depending on the extent, subtype, and underlying etiology of PMG, clinical manifestations may range from selective impairment of cognitive function to severe encephalopathy with intractable epilepsy. [dnatesting.uchicago.edu]
There is a wide spectrum of clinical manifestation in patients with PMG, varying from severe encephalopathy, mental retardation and refractory epilepsy to selective cognitive impairment. [moh-it.pure.elsevier.com]
Polymicrogyria is characterized by stable neurologic deficits, i.e., a “static encephalopathy.” The mildest form, unilateral focal polymicrogyria, may have minimal neurologic manifestations. [pediatricfocus.wordpress.com]
- Slurred Speech
CBPS patients have weakness of the face, throat, tongue and the chewing process, with lack of speech or slurred speech and drooling. Most have learning impairments (see entry Learning Disability), behaviour problems and epilepsy. [contact.org.uk]
Work up for polymicrogyria consists of a physical exam, a thorough medical history (including maternal pregnancy history and family history), and imaging tests. Congenital infections have been associated with polymicrogyria; the toxoplasmosis, rubella, cytomegalovirus, herpes simplex, and a TORCH screen may be performed for detection of human immunodeficiency virus (HIV) if clinically indicated.
Genetic testing for mutations can be performed. For example, BICD2 has been associated with perisylvian polymicrogyria . Screening for syndromes commonly associated with polymicrogyria, can be useful for determining etiology. Polymicrogyria is often an isolated condition, however, it can occur as a part of genetic syndromes such as 22q11.2 deletion syndrome, Aicardi syndrome, Adams-Oliver syndrome, Chudley-McCullough syndrome, Zellweger spectrum disorder, Galloway-Mowat syndrome, and Joubert syndrome .
Magnetic resonance imaging (MRI) is used to diagnose polymicrogyria . MRI images will show abnormalities of the surface of the cortex and the gray-white matter junction . In patients with polymicrogyria, the cortical surface will show a thickened appearance due to the fused and infolded gyri. Other imaging modalities such as computed tomography (CT) do not have sufficient resolution or contrast to show the small gyri characteristic of polymicrogyria.
Brain tissue can be examined at the time of autopsy or during neurosurgery. Gross examination of the cerebral cortex shows an abnormal brain surface consisting of complex convolutions with miniature, fused, superimposed folds and the pia meningeal layer extending across multiple folds . Microscopic examination reveals an unusually thin cerebral cortex with abnormal lamination.
OBJECTIVE: The role of resective surgery in the treatment of polymicrogyria (PMG)-related focal epilepsy is uncertain. [ncbi.nlm.nih.gov]
There are two main types of clinical studies: Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments. [rarediseases.info.nih.gov]
Treatment Medical management of seizures and supportive care. Reference: Diagnostic Imaging Osborn. [neuroradiologycases.com]
What is the treatment? There is no cure for Microcephaly. [chiarasjourney.com]
Treatment and prognosis No specific treatment of polymicrogyria per se is available. Treatment is symptomatic and particularly aimed at controlling epilepsy, a common sequela. Related Radiopaedia articles Promoted articles (advertising) [radiopaedia.org]
CONCLUSIONS: Late presenting epilepsy may be a predictor of aunilateral polymicrogyria and is associated with relatively good prognosis. CMV infection and the presence of asphyxia are predictors of worse prognosis. [ncbi.nlm.nih.gov]
CONCLUSION--Similar brain malformations occasionally reported in older patients confirm the clinical picture, sporadic occurrence, and prognosis found, allowing the validation of a unilateral perisylvian syndrome. [jnnp.bmj.com]
Congenital bilateral perisylvian syndrome (CBPS): Do concomitant oesophageal malformations indicate a poor prognosis? Neuropediatrics 2000; 31: 310–3. Yekeler E, Ozmen M, Genchellac H, Dursun M, Acunas G. [cmj.cumhuriyet.edu.tr]
Classification: Several types with various manifestations and etiologies have been noted. [medlink.com]
It is a highly heterogeneous malformation with variable clinical and imaging features, pathological findings, and etiologies. [ncbi.nlm.nih.gov]
It may be associated with a genetic etiology, or may be due to exogenic causes such as infection, or impaired hemodynamic disturbances. [dnatesting.uchicago.edu]
Intrauterine infection, ischemia, toxins or gene mutations are known etiology. [neuroradiologycases.com]
López Pino Localización: Anales de Pediatría: Publicación Oficial de la Asociación Española de Pediatría ( AEP ), ISSN 1695-4033, ISSN-e 1696-4608, Vol. 75, Nº. 6, 2011, págs. 358-364 Idioma: español Títulos paralelos: Polymicrogyria: epidemiology, neurological [dialnet.unirioja.es]
Epidemiology Currently the prevalence is unknown. Researchers believe that, although polymicrogyria in all its forms is a fairly common brain malformation, each individual disorder is rare in the population. [lifepersona.com]
View Article PubMed Google Scholar Kenneson A, Cannon MJ: Review and meta-analysis of the epidemiology of congenital cytomegalovirus (CMV) infection. Rev Med Virol 2007, 17: 253–276. [doi.org]
The pathophysiological bases are heterogeneous and include extrinsic factors and genetic causes. [ncbi.nlm.nih.gov]
It appears that intrauterine infection by cigomegalovirus (CMV) could be the basis of a significant percentage of them; In addition, in the last years, a great number of genes that could be involved in the pathophysiology of this type of cerebral malformations [lifepersona.com]
View Article PubMed PubMed Central Google Scholar Comi AM: Pathophysiology of Sturge-Weber syndrome. J Child Neurol 2003, 18: 509–516. [doi.org]
This situation suggests a need for more education regarding CMV modes of transmission and prevention on early prenatal visits. [ashg.org]
The ankle-foot orthotic can also be used to prevent further deformity of the joint. [medigoo.com]
Prevention Prevention is paramount and for this it is appropriate that parents be educated about common seizure presentations. [lifepersona.com]
Treatment with anticonvulsant drugs may help prevent, reduce, or control various types of epilepsy associated with CBPS. [rarediseases.org]
Mutations in the AKT3, CCND2, or PIK3R2 gene increase the activity of their respective proteins or prevent the proteins from being broken down when they should. [medlineplus.gov]
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