Retrospective Study Of Imaging Features Of Infantile Spasms And Its Effect On Outcomes

BackgroundInfantile spasms(IS),first reported by West in the 18th century,have a special form of spasms seizures,with electroencephalograms(EEG)characterized by hypsarrhythmia,accompanied by severe cognitive and motor retardation.IS is a common epileptic encephalopathy with a peak age of 3 to 7 months,and the incidence is about 2.0/10000-4.2/10000.IS can be caused by a variety of etiology,and the pathogenesis is unknown.After the onset,it can lead to mental motor stunting or even retrogression.At present,adrenocorticotropic hormone(ACTH),glucocorticoid,various types of anti-epileptic drugs,vitamin B6,ketogenic diet and surgical treatment are commonly used to treat IS.After various treatment regimens are applied in many patients,spasms are still difficult to control,and the optimization of treatment regimens has always been the focus of researchers.The etiology of IS are complex and diverse,and the International League Against Epilepsy(ILAE)classifies the etiology of epilepsy as structural,genetic,infectious,metabolic,immune and unknown.The U.S.Infantile Spasms Working Group classes the etiology of IS into symptomatic and cryptogenic.At present,ACTH,glucocorticoid and Vigabatrin are usually used as first-line therapeutic drugs for the treatment of different etiologies,although the dosage and course of medication may still be controversial.However,the selection of treatment regimens according to different etiologies has a profound impact on the therapeutic effect and prognosis.Imaging examination play an important role in the diagnosis of the etiology of IS.Imaging examination,such as MRI,can identify the majority of patients whether there are structural abnormalities in the brain,and combined with electro-clinical evaluation,clinicians can well judge the correlation between structural abnormalities and epilepsy.There are many types of structural abnormalities that can lead to IS,and studies have found that different structural abnormalities have different responses and prognosis to medication in IS patients.However,is there a structural abnormality that is highly related to IS incidence,except for tuberous sclerosis?By observing the imaging characteristics of IS patients and analyzing the effect of structural etiology on the effect of drug treatment,this study is of great significance for the clarity of high-risk pathogenic factors,the optimization of treatment plan and the evaluation of long-term prognosis.objectiveIn this study,the imaging characteristics of patients with IS were statistically analyzed to determine which structural abnormalities of the brain were the high-risk factors for IS,to analyze the influence of structural etiology on the treatment effect of IS,and to statistic the antiepileptic drugs used for patients whose seizure control time was longer than 24 weeks.Materials and MethodsCollected information on patients with IS who were first diagnosed at the Third Affiliated Hospital of Zhengzhou University from January 2014 to June 2019 and were not treated with the relevant medication,and initially obtained 278 patients with medical records.Collect medical records about the patients,including sex,age,past medical history,personal history and family history and focus on reviewing the perinatal period for preterm birth,low birth weight,asphyxia,hypoglycemia,hyperbilirubinemia and subsequent symptoms of encephalopathy(e.g.,coma,convulsions,etc.).The onset and development of IS were recorded,including the age of seizures observed by parents,the duration and frequency of seizures before treatment,the type of seizures and electroencephalogram,the type of antiepileptic drugs used,the genetic and metabolic examination,chromosome,genetic testing and imaging examination results.After telephone follow-up or outpatient follow-up,the patients’conditions were recorded from 2 to 24 weeks after methylprednisolone treatment and the antiepileptic drugs used for patients whose seizure control time was longer than 24 weeks.Later,36 patients who did not meet the criteria were excluded according to the inclusion and exclusion criteria,and 26 patients lost to follow-up and7 patients died were excluded.Finally,209 patients were included in the study.According to the characteristics of imaging examination,the patients with obvious abnormality in head MRI and/or CT,which were considered to be related to the occurrence and development of IS,were classified into the observation group(102cases),and the patients without structural abnormality were included into the control group(107 cases).SPSS 26.0 was used for statistical analysis.Enumeration data were expressed as the number of cases(%),andχ~2 test was used for comparison between the two groups.Logistic regression model was used to analyze the effect of brain structural abnormality on the short-term control rate of spastic seizure and the remission rate of EEG.P>0.05 indicates that the difference is statistically significant.ResultsImaging abnormalities in the observation group mainly included encephalomalacia(90.2%)and congenital brain malformation(9.8%),and encephalomalacia in parieto-occipital lobe was more common(49.0%),and 24.5%of them could be traced back to definite perinatal hypoglycemia.There was no significant difference in short-term control rate(χ~2=0.562,P=0.453)and recurrence rate(χ~2=1.834,P=0.176)of spasms between the observation group and the control group.The difference in EEG improvement rate(χ~2=3.957,P=0.047)was statistically significant.Logistic regression analysis indicated that the structural abnormality in the observation group was the high-risk factor for the failure of EEG improvement[P=0.048,OR(95%CI)=0.566(0.322,0.994)].The main antiepileptic drugs used in the two groups of patients with seizure control over 24 weeks were sodium valproate,topiramate,and levetiracetam.Conclusions(1)Encephalomalacia and congenital brain malformation were the main imaging features of IS,and parieto-occipital encephalomalacia was a high risk factor for IS.(2)The EEG improvement rate of patients with structural etiology in the observation group was lower.(3)The main antiepileptic drugs used in the two groups of patients with seizure control over 24 weeks were sodium valproate,topiramate,and levetiracetam.