Genotypic and phenotypic analysis of Korean patients with tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is a rare autosomal dominant disorder caused by mutations in the TSC1 or TSC2 gene. The aim of this study was to analyze the genotypes and phenotypes of Korean patients diagnosed with TSC and expand our understanding of this disorder. This retrospective observational study included 331 patients clinically diagnosed with TSC between November 1990 and April 2023 at Severance Children's Hospital, Seoul, South Korea. The demographic and clinical characteristics of the patients were investigated. Thirty novel variants were identified. Of the 331 patients, 188 underwent genetic testing, and genotype-phenotype variation was analyzed according to the type of gene mutation and functional domain. Fourty-nine patients (49/188, 26%) were had TSC1 mutations, 103 (55%) had TSC2 mutations, and 36 (19%) had no mutation identified (NMI). Hotspots were identified in exons 8 of TSC1 and exons 35 and 41 of TSC2. Patients with TSC2 mutations exhibited a significantly younger age at the time of seizure onset and had refractory epilepsy. Infantile epileptic spasms syndrome (IESS) was more common in the middle mutation domain of TSC2 than in the hamartin domain. Additionally, retinal hamartoma, cardiac rhabdomyoma, and renal abnormalities were significantly associated with TSC2 compared with other gene types. This study contributes to our understanding of TSC by expanding the genotypic spectrum with novel variants and providing insights into the clinical spectrum of patients with TSC in Korea.

Threshold of somatic mosaicism leading to brain dysfunction with focal epilepsy.

Somatic mosaicism in a fraction of brain cells causes neurodevelopmental disorders, including childhood intractable epilepsy. However, the threshold for somatic mosaicism leading to brain dysfunction is unknown. In this study, we induced various mosaic burdens in focal cortical dysplasia type II (FCD II) mice, featuring mTOR somatic mosaicism and spontaneous behavioural seizures. The mosaic burdens ranged from approximately 1000 to 40 000 neurons expressing the mTOR mutant in the somatosensory or medial prefrontal cortex. Surprisingly, approximately 8000-9000 neurons expressing the MTOR mutant, extrapolated to constitute 0.08%-0.09% of total cells or roughly 0.04% of variant allele frequency in the mouse hemicortex, were sufficient to trigger epileptic seizures. The mutational burden was correlated with seizure frequency and onset, with a higher tendency for electrographic inter-ictal spikes and beta- and gamma-frequency oscillations in FCD II mice exceeding the threshold. Moreover, mutation-negative FCD II patients in deep sequencing of their bulky brain tissues revealed somatic mosaicism of the mTOR pathway genes as low as 0.07% in resected brain tissues through ultra-deep targeted sequencing (up to 20 million reads). Thus, our study suggests that extremely low levels of somatic mosaicism can contribute to brain dysfunction.

Management of Uncomplicated Appendicitis in Adults: A Nationwide Analysis From 2018 to 2019.

INTRODUCTION: Nonoperative management (NOM) of uncomplicated appendicitis (UA) has been increasingly utilized in recent years. The aim of this study was to describe nationwide trends of sociodemographic characteristics, outcomes, and costs of patients undergoing medical versus surgical management for UA. METHODS: The 2018-2019 National (Nationwide) Inpatient Sample was queried for adults (age ≥18 y) with UA; diagnosis, as well as laparoscopic and open appendectomy, were defined by the International Classification of Diseases, 10th Revision, Clinical Modification codes. We examined several characteristics, including cost of care and length of hospital stay. RESULTS: Among the 167,125 patients with UA, 137,644 (82.4%) underwent operative management and 29,481 (17.6%) underwent NOM. In bivariate analysis, we found that patients who had NOM were older (53 versus 43 y, P < 0.001) and more likely to have Medicare (33.6% versus 16.1%, P < 0.001), with higher prevalence of comorbidities such as diabetes (7.8% versus 5.5%, P < 0.001). The majority of NOM patients were treated at urban teaching hospitals (74.5% versus 66.3%, P < 0.001). They had longer LOS's (5.4 versus 2.3 d, P < 0.001) with higher inpatient costs ($15,584 versus $11,559, P < 0.001) than those who had an appendectomy. Through logistic regression we found that older patients had up to 4.03-times greater odds of undergoing NOM (95% CI: 3.22-5.05, P < 0.001). CONCLUSIONS: NOM of UA is more commonly utilized in patients with comorbidities, older age, and those treated in teaching hospitals. This may, however, come at the price of longer length of stay and higher costs. Further guidelines need to be developed to clearly delineate which patients could benefit from NOM.

Long-term exposure to high perceived temperature and risk of mortality among patients with chronic kidney disease.

Health risks due to climate change are emerging, particularly from high-temperature exposure. The perceived temperature is an equivalent temperature based on the complete heat budget model of the human body. Therefore, we aimed to analyze the effect of perceived temperature on overall mortality among patients with chronic kidney disease. In total, 32,870 patients with chronic kidney disease in Seoul participated in this retrospective study (2001-2018) at three medical centers. The perceived temperature during the summer season was calculated using meteorological factors, including the air temperature near the automated weather station, dew point temperature, wind velocity, and total cloud amount. We assessed the association between perceived temperature using Kriging spatial interpolation and mortality in patients with CKD in the time-varying Cox proportional hazards model that was adjusted for sex, age, body mass index, hypertension, diabetes mellitus, estimated glomerular filtration rate, smoking, alcohol consumption, and educational level. During the 6.14 ± 3.96 years of follow-up, 3863 deaths were recorded. In multivariable analysis, the average level of perceived temperature and maximum level of perceived temperature demonstrated an increased risk of overall mortality among patients with chronic kidney disease. The concordance index for mortality of perceived temperature was higher than temperature, discomfort index, and heat index. When stratified by age, diabetes mellitus, and estimated glomerular filtration rate, patients with chronic kidney disease with young age (age <65 years) showed higher hazard ratio for mortality (interaction P = 0.049). Moreover, the risk of death in the winter and spring seasons was more significant compared to that of the summer and autumn seasons. Therefore, long-term exposure to high perceived temperature during summer increases the risk of mortality among patients with chronic kidney disease.

A pseudo-dilemma: Are we over-diagnosing and over-treating traumatic splenic intraparenchymal pseudoaneurysms?

BACKGROUND: Splenic embolization for traumatic vascular abnormalities in stable patients is a common practice. We hypothesize that modern contrast-enhanced computed tomography (CT) over diagnoses posttraumatic splenic vascular lesions, such as intraparenchymal pseudoaneurysms (PSA) that may not require embolization. METHODS: We reviewed the experience at our high-volume center with endovascular management of blunt splenic injuries from January 2016 to December 2021. Multidisciplinary review was used to compared initial CT findings with subsequent angiography, analyzing management and outcomes of identified vascular lesions. RESULTS: Of 853 splenic injuries managed overall during the study period, 255 (29.9%) underwent angiography of the spleen at any point during hospitalization. Vascular lesions were identified on 58% of initial CTs; extravasation (12.2%) and PSA (51.0%). Angiography was performed a mean of 22 hours after admission, with 38% done within 6 hours. Embolization was performed for 90.5% (231) of patients. Among the 130 patients with PSA on initial CT, 36 (27.7%) had no visible lesion on subsequent angiogram. From the 125 individuals who did not have a PSA identified on their initial CT, 67 (54%) had a PSA seen on subsequent angiography. On postembolization CT at 48 hours to 72 hours, persistently perfused splenic PSAs were seen in 41.0% (48/117) of those with and 22.2% (2/9) without embolization. Only one of 24 (4.1%) patients with PSA on angiography observed without embolization required delayed splenectomy, whereas 6.9% (16/231) in the embolized group had splenectomy at a mean of 5.5 ± 4 days after admission. CONCLUSION: There is a high rate of discordance between CT and angiographic identification of splenic PSAs. Even when identified at angiogram and embolized, close to half will remain perfused on follow-up imaging. These findings question the use of routine angioembolization for all splenic PSAs. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Rates and risk factors for anastomotic leak following blunt trauma-associated bucket handle intestinal injuries: a multicenter study.

Objectives: The risk factors for anastomotic leak (AL) after resection and primary anastomosis for traumatic bucket handle injury (BHI) have not been previously defined. This multicenter study was conducted to address this knowledge gap. Methods: This is a multicenter retrospective study on small intestine and colonic BHIs from blunt trauma between 2010 and 2021. Baseline patient characteristics, risk factors, presence of shock and transfusion, operative details, and clinical outcomes were compared using R. Results: Data on 395 subjects were submitted by 12 trauma centers, of whom 33 (8.1%) patients developed AL. Baseline details were similar, except for a higher proportion of patients in the AL group who had medical comorbidities such as diabetes, hypertension, and obesity (60.6% vs. 37.3%, p=0.015). AL had higher rates of surgical site infections (13.4% vs. 5.3%, p=0.004) and organ space infections (65.2% vs. 11.7%, p<0.001), along with higher readmission and reoperation rates (48.4% vs. 9.1%, p<0.001, and 39.4% vs. 11.6%, p<0.001, respectively). There was no difference in intensive care unit length of stay or mortality (p>0.05). More patients with AL were discharged with an ostomy (69.7% vs. 7.3%, p<0.001), and the mean duration until ostomy reversal was 5.85±3 months (range 2-12.4 months). The risk of AL significantly increased when the initial operation was a damage control procedure, after adjusting for age, sex, injury severity, presence of one or more comorbidities, shock, transfusion of >6 units of packed red blood cells, and site of injury (adjusted RR=2.32 (1.13, 5.17)), none of which were independent risk factors in themselves. Conclusion: Damage control surgery performed as the initial operation appears to double the risk of AL after intestinal BHI, even after controlling for other markers of injury severity. Level of evidence: III.

The safety and efficacy of laparoscopic retrograde appendicectomy, base-to-tip approach.

Background: Laparoscopic appendicectomy is one of the most frequently performed surgical procedures worldwide. There is limited evidence evaluating the role and safety of laparoscopic retrograde appendicectomy (LRA), base to tip approach, compared to standard laparoscopic antegrade appendicectomy (LAA), tip to base approach. This study aims to assess the safety of LRA compared to LAA in terms of intra-abdominal collection (IAC) rate and using Sunshine Appendicitis Grading System (SAGS). Methods: Records of two-hundred and seventy-three patients undergoing laparoscopic appendicectomy by LAA and LRA approaches were analysed. The severity of appendicitis was rated using a standardised Sunshine Appendicitis Grading System (SAGS) score intra-operatively. The primary outcome measure was the occurrence of an intra-abdominal collection, and secondary measures were procedure time, post-operative length of stay and other complications. Results: Of the two-hundred and seventy-three patients, there were two patients who developed an intra-abdominal collection. Both patients were in the LAA group with SAGS IV scores. Between SAGS IV patients, Chi-squared p value of 0.6691. Therefore, there was no statically significant difference in the intra-abdominal collection (IAC) rate between LAA and LRA groups from this study. Conclusions: The current study has shown that laparoscopic retrograde appendicectomy (LRA) does not increase risk of intra-abdominal collection compared to laparoscopic antegrade appendicectomy (LAA) within the limit of this study.

Anastomotic leak rates after repair of mesenteric bucket-handle injuries: A multi-center retrospective cohort study.

BACKGROUND: Primary aim was to assess the relative risk (RR) of anastomotic leak (AL) in intestinal bucket-handle (BH) compared to non-BH injury. METHODS: Multi-center study comparing AL in BH from blunt trauma 2010-2021 compared to non-BH intestinal injuries. RR was calculated for small bowel and colonic injury using R. RESULTS: AL occurred in 20/385 (5.2%) of BH vs. 4/225 (1.8%) of non-BH small intestine injury. AL was diagnosed 11.6 ± 5.6 days from index operation in small intestine BH and 9.7 ± 4.3 days in colonic BH. Adjusted RR for AL was 2.32 [0.77-6.95] for small intestinal and 4.83 [1.47-15.89] for colonic injuries. AL increased infections, ventilator days, ICU & total length of stay, reoperation, and readmission rates, although mortality was unchanged. CONCLUSION: BH carries a significantly higher risk of AL, particularly in the colon, than other blunt intestinal injuries.

Clinical Features, Neuropathology, and Surgical Outcome in Patients With Refractory Epilepsy and Brain Somatic Variants in the SLC35A2 Gene.

BACKGROUND AND OBJECTIVES: The SLC35A2 gene, located at chromosome Xp11.23, encodes for a uridine diphosphate-galactose transporter. We describe clinical, genetic, neuroimaging, EEG, and histopathologic findings and assess possible predictors of postoperative seizure and cognitive outcome in 47 patients with refractory epilepsy and brain somatic SLC35A2 gene variants. METHODS: This is a retrospective multicenter study where we performed a descriptive analysis and classical hypothesis testing. We included the variables of interest significantly associated with the outcomes in the generalized linear models. RESULTS: Two main phenotypes were associated with brain somatic SLC35A2 variants: (1) early epileptic encephalopathy (EE, 39 patients) with epileptic spasms as the predominant seizure type and moderate to severe intellectual disability and (2) drug-resistant focal epilepsy (DR-FE, 8 patients) associated with normal/borderline cognitive function and specific neuropsychological deficits. Brain MRI was abnormal in all patients with EE and in 50% of those with DR-FE. Histopathology review identified mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy in 44/47 patients and was inconclusive in 3. The 47 patients harbored 42 distinct mosaic SLC35A2 variants, including 14 (33.3%) missense, 13 (30.9%) frameshift, 10 (23.8%) nonsense, 4 (9.5%) in-frame deletions/duplications, and 1 (2.4%) splicing variant. Variant allele frequencies (VAFs) ranged from 1.4% to 52.6% (mean VAF: 17.3 ± 13.5). At last follow-up (35.5 ± 21.5 months), 30 patients (63.8%) were in Engel Class I, of which 26 (55.3%) were in Class IA. Cognitive performances remained unchanged in most patients after surgery. Regression analyses showed that the probability of achieving both Engel Class IA and Class I outcomes, adjusted by age at seizure onset, was lower when the duration of epilepsy increased and higher when postoperative EEG was normal or improved. Lower brain VAF was associated with improved postoperative cognitive outcome in the analysis of associations, but this finding was not confirmed in regression analyses. DISCUSSION: Brain somatic SLC35A2 gene variants are associated with 2 main clinical phenotypes, EE and DR-FE, and a histopathologic diagnosis of MOGHE. Additional studies will be needed to delineate any possible correlation between specific genetic variants, mutational load in the epileptogenic tissue, and surgical outcomes.

Efficacy of the Ketogenic Diet for Pediatric Epilepsy According to the Presence of Detectable Somatic mTOR Pathway Mutations in the Brain.

BACKGROUND AND PURPOSE: A multifactorial antiepileptic mechanism underlies the ketogenic diet (KD), and one of the proposed mechanisms of action is that the KD inhibits the mammalian target of rapamycin (mTOR) pathway. To test this clinically, this study aimed to determine the efficacy of the KD in patients with pathologically confirmed focal cortical dysplasia (FCD) due to genetically identifiable mTOR pathway dysregulation. METHODS: A cohort of patients with pathologically confirmed FCD after epilepsy surgery and who were screened for the presence of germline and somatic mutations related to the mTOR pathway in peripheral blood and resected brain tissue was constructed prospectively. A retrospective review of the efficacy of the prior KD in these patients was performed. RESULTS: Twenty-five patients with pathologically confirmed FCD and who were screened for the presence of detectable somatic mTOR pathway mutations had received a sufficient KD. Twelve of these patients (48.0%) had germline or somatic detectable mTOR pathway mutations. A response was defined as a ≥50% reduction in seizure frequency. The efficacy of the KD after 3 months of dietary therapy was superior in patients with detectable mTOR pathway mutations than in patients without detectable mTOR pathway mutations, although the difference was not statistically significant (responder rates of 58.3% vs. 38.5%, p=0.434). CONCLUSIONS: A greater proportion of patients with mTOR pathway responded to the KD, but there was no statistically significant difference in efficacy of the KD between patients with and without detectable mTOR pathway mutations. Further study is warranted due to the smallness of the sample and the limited number of mTOR pathway genes tested in this study.

Zinner Syndrome with Ectopic Ureter Remnant.

INTRODUCTION: Zinner syndrome is a rare congenital abnormality defined by a clinical triad of unilateral renal agenesis, ipsilateral seminal vesicle cyst, and ipsilateral ejaculatory duct obstruction. CASE PRESENTATION: Most patients are asymptomatic, but if the cystic dilatation of the seminal vesicle becomes significant, it can result in urinary symptoms such as dysuria and urinary retention. This rare developmental anomaly related to mesonephric duct can also present with other abnormalities. CONCLUSION: Here, we report our experience of Zinner syndrome with bladder outlet obstruction and an ectopic ureter remnant.

Near Disappearance of Splenorrhaphy as an Operative Strategy for Splenic Preservation After Trauma.

BACKGROUND: Splenorrhaphy was once used to achieve splenic preservation in up to 40% of splenic injuries. With increasing use of nonoperative management and angioembolization, operative therapy is less common and splenic injuries treated operatively are usually high grade. Patients are often unstable, making splenic salvage unwise. Modern surgeons may no longer possess the knowledge to perform splenorrhaphy. METHODS: The records of adult trauma patients with splenic injuries from September 2014 to November 2018 at an urban level I trauma center were reviewed retrospectively. Data including American Association for the Surgery of Trauma splenic organ injury scale, type of intervention, splenorrhaphy technique, and need for delayed splenectomy were collected. This contemporary cohort (CC) was compared to a historical cohort (HC) of splenic injuries at a single center from 1980 to 1989 (Ann Surg 1990; 211: 369). RESULTS: From 2014 to 2018, 717 adult patients had splenic injuries. Initial management included 157 (21.9%) emergent splenectomy, 158 (22.0%) angiogram ± embolization, 371 (51.7%) observation, and only 10 (1.4%) splenorrhaphy. The HC included a total of 553 splenic injuries, of which 313 (56.6%) underwent splenectomy, while splenorrhaphy was performed in 240 (43.4%). Those who underwent splenorrhaphy in each cohort (CC vs HC) were compared. CONCLUSION: The success rate of splenorrhaphy has not changed. However, splenorrhaphy now involves only electrocautery with topical hemostatic agents and is used primarily in low-grade injuries. Suture repair and partial splenectomy seem to be "lost arts" in modern trauma care.

Conventional-Dose CT Versus 2-mSv CT for Right Colonic Diverticulitis as an Alternate Diagnosis of Appendicitis: Secondary Analysis of Large Pragmatic Randomized Trial Data.

BACKGROUND. Adoption of low-dose CT for the diagnosis of appendicitis has been slow in children and in adults, partly because of concern about missing alternative diagnoses including right colonic diverticulitis. OBJECTIVE. The purpose of our study was to retrospectively compare the diagnostic performance of IV contrast-enhanced 2-mSv and conventional-dose CT (CDCT) for the diagnosis of right colonic diverticulitis in adolescents and young adults with suspected appendicitis. METHODS. This post hoc analysis of a prospective randomized controlled trial included 3074 patients (1672 female patients and 1402 male patients) ranging in age from 15 to 44 years old (mean ± SD, 28 ± 9 years) from 20 hospitals. From December 2013 to August 2016, patients were randomized to either the 2-mSv CT group (n = 1535 patients) or the CDCT (median, 7 mSv) group (n = 1539 patients). A total of 161 radiologists prospectively issued CT reports in which they suggested alternative diagnoses for 976 (2-mSv CT) and 924 (CDCT) patients. Seven independent assessors adjudicated final diagnoses on the basis of clinical and CT findings. Endpoints of test-positives, test-negatives, sensitivity, and specificity for right colonic diverticulitis were compared using chi-square and Mann-Whitney U tests. Characteristics and disposition of patients with test-positive results were assessed. Four readers retrospectively reviewed CT images of 400 patients selected from the trial (113 and 108 patients with diverticulitis from 2-mSv CT and CDCT groups, respectively) to evaluate interobserver agreement for right colonic diverticulitis in terms of Gwet coefficients. RESULTS. Between-group differences were minute for most endpoints related to right colonic diverticulitis: test-positives (difference, 0.2% [95% CI, -1.8% to 2.1%]; 7.8% [119/1535 patients] vs 7.6% [117/1539 patients]; p = .93), test-negatives (0.5% [95% CI, -1.5% to 2.5%]; 91.7% [1407/1535] vs 91.2% [1403/1539]; p = .67), sensitivity (0% [95% CI, -6% to 6%]; 95% [110/116] vs 95% [105/111]; p > .99), and specificity (0.3% [95% CI, -0.5% to 0.9%]; 99.4% [1401/1410] vs 99.1% [1397/1409]; p = .66). The characteristics and disposition of test-positive patients were similar between the two groups. Gwet coefficients were high and comparable between the two groups (2-mSv CT vs CDCT, 0.849 vs 0.889; p = .20). CONCLUSION. Two-millisievert CT is comparable to conventional-dose CT for the diagnosis of right colonic diverticulitis. CLINICAL IMPACT. By mitigating concern about a missed diagnosis of right colonic diverticulitis, the results further support the use of low-dose CT in patients with suspected appendicitis. TRIAL REGISTRATION. ClinicalTrials.gov NCT01925014.

A Fibroma of Tendon Sheath Causing Carpal Tunnel Syndrome: A Case Report of an Atypical Clinical Presentation.

Fibroma of the tendon sheath is a benign slow-growing fibrous tumor. Although rare, cases occurring in the upper extremities usually involve the fingers. It appears as a well-defined, roundor oval-shaped mass originating from the flexor tendon. Abundant fibrous stroma makes fibromas appear as a low intensity mass in all MRI sequences. Most of the fibromas manifest as painless soft tissue masses. Herein, we report a case of fibroma of the tendon sheath with an unusual clinical presentation, triggering carpal tunnel syndrome during wrist movement.

Factors associated with seizure and cognitive outcomes after epilepsy surgery for low-grade epilepsy-associated neuroepithelial tumors in children.

Low-grade epilepsy-associated neuroepithelial tumors (LEATs) are responsible for drug-resistant chronic focal epilepsy, and are the second-most common reason for epilepsy surgery in children. LEATs are extremely responsive to surgical treatment, and therefore epilepsy surgery should be considered as a treatment option for LEATs. However, the optimal time for surgery remains controversial, and surgeries are often delayed. In this review, we reviewed published article on the factors associated with seizure and cognitive outcomes after epilepsy surgery for LEATs in children to help clinicians in their decision whether to pursue epilepsy surgery for LEATs. The achievement of gross total resection may be the most important prognostic factor for seizure freedom. A shorter duration of epilepsy, a younger age at surgery, and extended resection of temporal lobe tumors have also been suggested as favorable prognostic factors in terms of seizure control. Poor cognitive function in children with LEATs is associated with a longer duration of epilepsy and a younger age at seizure onset.

Radiologic and Pathologic Findings of Atypical Ductal Hyperplasia in the Male Breast: Case Report and Literature Review.

In this case report, we present the radiologic and pathologic findings of atypical ductal hyperplasia (ADH) in the male breast. It is well known that a high-risk lesion such as ADH is a precursor of breast cancer in females. However, the clinical significance of these lesions in the male breast is still uncertain because male breasts mainly consist of ducts without lobule formation, unlike the female breast. To our knowledge, imaging findings of ADH in the male breast have not been reported previously, except for a few studies on the pathologic findings of these lesions. Through this paper, we would like to present the possible imaging features of this high-risk lesion in the male breast and review the related literature.

Precise detection of low-level somatic mutation in resected epilepsy brain tissue.

Low-level somatic mutations have been shown to be the major genetic etiology of intractable epilepsy. The extents thereof, however, have yet to be systematically and accurately explored in a large cohort of resected epilepsy brain tissues. Moreover, clinically useful and precise analysis tools for detecting low-level somatic mutations from unmatched formalin-fixed paraffin-embedded (FFPE) brain samples, the most clinically relevant samples, are still lacking. In total, 446 tissues samples from 232 intractable epilepsy patients with various brain pathologies were analyzed using deep sequencing (average read depth, 1112x) of known epilepsy-related genes (up to 28 genes) followed by confirmatory site-specific amplicon sequencing. Pathogenic mutations were discovered in 31.9% (74 of 232) of the resected epilepsy brain tissues and were recurrently found in only eight major focal epilepsy genes, including AKT3, DEPDC5, MTOR, PIK3CA, TSC1, TSC2, SCL35A2, and BRAF. Somatic mutations, two-hit mutations, and germline mutations accounted for 22.0% (51), 0.9% (2), and 9.1% (21) of the patients with intractable epilepsy, respectively. The majority of pathogenic somatic mutations (62.3%, 33 of 53) had a low variant allelic frequency of less than 5%. The use of deep sequencing replicates in the eight major focal epilepsy genes robustly increased PPVs to 50-100% and sensitivities to 71-100%. In an independent FCDII cohort of only unmatched FFPE brain tissues, deep sequencing replicates in the eight major focal epilepsy genes identified pathogenic somatic mutations in 33.3% (5 of 15) of FCDII individuals (similar to the genetic detecting rate in the entire FCDII cohort) without any false-positive calls. Deep sequencing replicates of major focal epilepsy genes in unmatched FFPE brain tissues can be used to accurately and efficiently detect low-level somatic mutations, thereby improving overall patient care by enriching genetic counseling and informing treatment decisions.