External ear malformations and cardiac and renal anomalies: A systematic review and meta-analysis.

CONTEXT: External Ear Malformations (EEM) continue to be a common malformation seen in the pediatric patient population. This study aims to further elucidate the correlation between EEM and cardiac and renal anomalies. OBJECTIVE: A systematic review and meta-analysis to study the incidence of cardiac and renal anomalies associated with syndromic and isolated (EEM). DATA SOURCES: The literature search spanned multiple databases, including Google Scholar, PubMed, Scopus, Web of Science, and MEDLINE. STUDY SELECTION: Studies must be focused on EEM and cardiac and/or renal anomalies. Only articles written in English were included. DATA EXTRACTION: General study characteristics, number of EEM patients, number of cardiac and renal anomalies and whether cases were syndromic were extracted from the studies. RESULTS: Of 1,058 initial studies, 33 were included for meta-analyses. Mean JBI score for all included studies was 92.06%, indicating acceptable study quality. Interrater reliability was high, with a Cohen kappa score for all studies of 0.94. The resulting pooled prevalence of cardiac abnormalities was 20% [95% CI:13-28%], while renal abnormalities were 13% [95% CI: 7-20%]. The most common anomalies were VSD (3.725%) and renal agenesis (2.04%). The presence of syndrome data across studies was not a significant modifier of prevalence rates. LIMITATIONS: Primary limitation is due to heterogeneity in individual study methodology and reporting standards. CONCLUSIONS: These results highlight a higher prevalence of cardiac-related conditions than renal anomalies in patients with both syndromic and non-syndromic EEM in the included studies, underscoring the need for thorough clinical evaluations.

Blastic plasmacytoid dendritic cell neoplasm: a rare external ear lesion presenting with leukaemia.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive haematological malignancy, typically characterised by cutaneous lesions and bone marrow involvement. We present a unique case of a woman in her 70s, initially seen for a spontaneous swelling on her left external ear resembling a haematoma, which recurred after initial treatment, triggering further evaluation.Diagnostic challenges arose as the patient displayed positive markers for Myeloperoxidase (MPO) (p-ANCA), suggesting vasculitis. Dermatology considered various differential diagnoses, but imaging and tests ruled out significant pathology. Steroid treatment led to improvement, but coincided with a surge in white cell count (WCC), prompting an urgent haematological review.Subsequent investigations, including a punch biopsy of the external ear and a bone marrow biopsy revealed BPDCN concurrent with chronic myelomonocytic leukaemia. This case highlights the challenging diagnostic journey, emphasising the need for multidisciplinary collaboration and the potential for unique BPDCN presentations, expanding our understanding of this malignancy.

Mirror Ear: A Rare Case of Polyotia.

Polyotia is an anomaly of the external auricle in which the accessory auricle is large enough to closely resemble an additional pinna rather than a skin remnant and cartilage. Polyotia, also known as mirror ear or accessory ear, is a type of ear anomaly in the tragus area, but the term refers to substantial anomalies which resemble an accessory ear, unlike a pre-auricular tag. It is an extremely rare condition and to date, less than 30 cases of polyotia have been reported according to a review of the literature. A variety of theories has been proposed for development of such abnormal external auricle. We report two cases of polyotia which presented to Dhulikhel Hospital ENT OPD that was successfully corrected surgically. An 8-year-old boy and a 14-year-old boy presented with a large accessory anomalous auricle on left and right ear respectively. The accessory auricle was composed of an elastic cartilaginous component covered with skin and was positioned anteriorly to the original auricle in both the cases. The anomaly was not as large as the patient's external auricle, rather it mirrored the external auricle. On the opposite ear both the cases presented with preauricular skin tag. Surgical correction was done by dissecting the skin free from the duplicated cartilage via an incision along the free edge of the helix the duplicated cartilage was contoured to fill the pre-tragal hollow and the tragus reconstructed with a free cartilage graft.

[Auricular and periauricular pathologies in the ENT department of Sylvanus Olympio Teaching Hospital in Lome (Togo)]. / Pathologies auriculaires et périauriculaires au service d'ORL du Centre hospitalier universitaire Sylvanus Olympio de Lomé (Togo).

Objective: The aim of this study is to describe the epidemiological aspects, clinical features and principles of management of different types of auricular and peri-auricular pathologies. Patients and Methods: This is a 5-year retrospective descriptive study (from May 1, 2018 to April 30, 2023) of the records of patients who consulted for a functional or cosmetic complaint relating to the auricle or periauricular region in the ENT and cervico-facial surgery department of the Centre hospitalier universitaire Sylvanus Olympio. Results: A total of 159 cases over 5 years, i.e. an annual frequency of 31 cases, met the study criteria. The mean age of the patients was 22.2 years. Children and students accounted for 24.5% and 23.9% of cases respectively. Auricular pathologies accounted for 64.8% of cases and peri-auricular pathologies for 36.2%.Tumors and trauma accounted for 33.3% and 29.6% of cases respectively, and congenital pathologies were found in 29.9% of cases. Among traumatic lesions, intentional assault and battery was the cause in 21.3%, followed by road accidents in 17.2%. The right ear was affected in 48% and the lobule in 40.4%. Keloids accounted for 17.6% of all cases, and 53% of tumors and pseudotumors. The left ear was involved in 50% of cases. Piercing was the cause of keloids in 10.7% of cases. Conclusion: Auricular and peri-auricular pathologies were dominated by benign tumors, trauma and congenital pathologies, and involved young subjects. Management is based on the type of lesion, with functional and aesthetic considerations in mind.

[Exploration of technique for preservation of external-middle ear structure in surgery of jugular foramen paraganglioma （appended 2 case reports）].

Objective:To investigate the feasibility and effect of the modified surgery of the classic infratemporal fossa type A approach for the surgical treatment of jugular foramen paraganglioma with preservation of the external and middle ear structures. Methods:The medical data of 2 patients with jugular foraminal paraganglioma treated by sublabyrinthic-transmastoid approach were retrospectively analyzed. The clinical feature, degree of tumor resection, postoperative facial nerve function and hearing retention, and the incidence of postoperative complications were evaluated. Results:Two patients were both female, and were pathologically confirmed as paraganglioma. The tumor of case 1 was staged as C2De1, and case 2 as C1De1. Tumors were completely resected in both patients. Case 1 suffered infection after surgery, with residual tympanic membrane perforation and mixed deafness. Case 2 developed mild facial paralysis（grade Ⅱ） after surgery, and recovered after symptomatic treatment. There was no tumor residue or recurrence during half a year of follow-up. Conclusion:Surgical treatment of certain paragangliomas in the jugular foramen with a combined sublabyrinthic-transmastoid and upper neck approach might achieve both complete resection of the tumor and preserving the structure and function of the outer-middle ear. This procedure is suitable for paragangliomas restricted in the jugular foramen area, with no or limited involvement of the internal carotid artery（C1 or C2）, and with no or mild hearing loss.

Single-stage reconstruction of severe question mark ear with the absence of large portions of the lobule using affected cartilage graft and 3 flaps.

BACKGROUND: Question mark ear (QME) is a congenital abnormality characterized by a prominent curve within the helix that resembles a question mark. Several surgical reconstruction techniques have been proposed to treat this deformity. In this study, we aimed to evaluate the cosmetic outcomes of a new cartilage and postauricular flap surgical reconstruction technique for patients diagnosed with severe QME. METHOD: From 2017 to 2023, 33 patients with severe QMEs were treated with a new reconstruction surgical technique at the Plastic Surgery Hospital of Peking Union Medical College. The perimeter, width, length, and auriculocephalic angles of both ears were measured and compared to assess the symmetry. The patient's satisfaction with the surgical outcomes and incidence of post-operative complications were also evaluated. The average follow-up duration was 15.48 months. RESULTS: The auricular perimeter, width, and length changed significantly after surgery. The dimensions of the left and right ear did not vary significantly in patients with unilateral or bilateral severe QME after surgery and at the end of the 1-year follow-up. Most patients (87.88%) or carers were satisfied with the cosmetic outcomes after surgery. All patients underwent suture removal 14 days after surgery and exhibited excellent wound healing without any complications such as hematoma, infection, and flap necrosis. CONCLUSION: Our new surgical reconstruction technique for severe QME resulted in good cosmetic outcomes, high patient satisfaction, fast recovery, and no post-operative complications.

Auricular spoon-shaped crus malformation including variants: Clinical features and a novel surgical approach.

BACKGROUND: Certain auricular malformations are uncommon and lack generally accepted diagnostic names. This study investigates an uncommon complex auricular malformation known as auricular spoon-shaped crus malformation providing a detailed description of its external characteristics. Additionally, an effective surgical approach is proposed. METHODS: Between 1991 and 2023, 12 auricles in 11 patients with auricular spoon-shaped crus malformation including variants were surgically treated at our center. Patient medical records and photographic data were retrospectively reviewed. RESULTS: Each auricle exhibited 2 to 4 major structural deformities within the 5 areas of the superior crus, inferior crus, and stem of the antihelix, helical crus, and earlobe. These deformities resulted in depression between the antihelix and antitragus, vertical shortening, horizontal elongation of the auricle, and/or drooping of the ear. Three patients displayed a low positioning of the malformed ear, and 8 patients exhibited mild to moderate hemifacial microsomia. In corrections we conducted earlier, we utilized various methods with variable aesthetic outcomes. Recently, an improved corrective method we implemented yielded consistently promising aesthetic results. We have confidence that adopting the surgical approach we suggest can lead to promising aesthetic results when addressing this malformation. Furthermore, we hope that the presented malformation will be recognized as a primary auricular malformation by auricular surgeons in the future.

The pixie ear: How to prevent and correct it-a review of the literature.

As the life expectancy of the population continues to increase, more facial-rejuvenating procedures are sought. As the number of facelift procedures increases, it is mandatory to acknowledge, and most importantly prevent, any possible associated complications. One of the complications after rhytidectomy, and a sign of facelift, is the so-called "pixie ear deformity" or "bat ear." This is regarded as a telltale sign of a facelift procedure and appears to be identified in 5% of earlobe inset cases. The ear's location is a crucial hallmark of an aesthetically pleasing face, not only by itself but also in relation with other aesthetic units. When performing a facelift procedure, tension vectors of the rhytidectomy flap could cause alterations in ear's position and appearance: the ear loses its great mobility and becomes more fixed in its acquired position, resulting in a "stuck-on" appearance. The auricle is displaced following an anteroinferior direction, with the otobasion inferius (the most caudal anterior attachment of the earlobe to the cheek) being dislocated from its original more posterior and upper position to a new more anterior and caudal location. The displacement of the auricle is usually accompanied by distortion of the earlobe rotating forward and becoming more anterior than the rest of the ear. In recent decades, many techniques and procedures have been described to prevent and correct the pixie ear; in this review, we aim to analyze and describe them comprehensively.

One-Year Results of Ear Reconstruction with 3D Printed Implants.

PURPOSE: External ear reconstruction has been a challenging subject for plastic surgeons for decades. Popular methods using autologous costal cartilage or polyethylene still have their drawbacks. With the advance of three-dimensional (3D) printing technique, bioscaffold engineering using synthetic polymer draws attention as an alternative. This is a clinical trial of ear reconstruction using 3D printed scaffold, presented with clinical results after 1 year. MATERIALS AND METHODS: From 2021 to 2022, five adult patients with unilateral microtia underwent two-staged total ear reconstruction using 3D printed implants. For each patient, a patient-specific 3D printed scaffold was designed and produced with polycaprolactone (PCL) based on computed tomography images, using fused deposition modeling. Computed tomography scan was obtained preoperatively, within 2 weeks following the surgery and after 1 year, to compare the volume of the normal side and the reconstructed ear. At 1-year visit, clinical photo was taken for scoring by two surgeons and patients themselves. RESULTS: All five patients had completely healed reconstructed ear at 1-year follow-up. On average, the volume of reconstructed ear was 161.54% of that of the normal side ear. In a range of 0 to 10, objective assessors gave scores 3 to 6, whereas patients gave scores 8 to 10. CONCLUSION: External ear reconstruction using 3D printed PCL implant showed durable, safe results reflected by excellent volume restoration and patient satisfaction at 1 year postoperatively. Further clinical follow-up with more cases and refinement of scaffold with advancing bioprinting technique is anticipated. The study's plan and results have been registered with the Clinical Research Information Service (CRIS No. 3-2019-0306) and the Ministry of Food and Drug Safety (MFDS No. 1182).

Clinical and social success in epithetic ear rehabilitation - Retrospectively evaluating the long-term survival of auricular implants.

PURPOSE: The aim of this study was to evaluate existing staging recommendations for peri-implantitis and its applicability for auricular bone anchoring. MATERIALS AND METHODS: In this cross-sectional study, 44 patients treated with 47 ear epitheses and 128 implants were analyzed over 191.6 months (mean). Peri-implant sulcus depth, sulcus fluid flow rate, and peri-implant skin reaction, as well as cleaning habits and patients' quality of life, were analyzed. Mixed effect linear and mixed effect ordered logistic regression models were used. RESULTS: Two of the 128 implants were lost (1.6 %). A total of 14.5 % of all patients presented light erythemas, 19.4 % showed stage 2, 4.8 % stage 3, and 12.9 % an acute infection according to Holgers. A correlation between skin reaction and sulcus fluid flow rate was observed, when grouping patients with acute signs of inflammation. Concerning patient satisfaction, 58.1 % of the patients were highly satisfied with their epitheses, 39.5 % very satisfied, and one patient was just satisfied. Younger age correlated with lower satisfaction rates. CONCLUSION: Implant-retained auricular epitheses are a safe, highly sufficient and satisfying way of extending ear reconstruction. Sulcus depth and skin reaction are quick and valuable assessment tools in auricular implants, but skin reaction alone was clinically insufficient to predict peri-implant pocket inflammation.

Efficiency of ear molding for treating constricted ears of different severity.

PURPOSE: To investigate the treatment time and efficiency of constricted ears of different severity after correction. MATERIALS AND METHODS: We included the patients with constricted ear presented to our hospital for treatment between December 2021 and December 2023 in this retrospective analysis. The patients were divided into class I, II and III groups based on the severity of the constriction. Then we collected the data on classification of severity from each patient, together with sex, family history, age at initial correction, being informed upon diagnosis after birth, as well as utilization of auricle correction system. Logistic regression analysis was performed to identify the factors associated with the treatment time and efficiency. RESULTS: The correction system yielded a high effective rate in the constricted ears. The treatment time in class II was significantly longer compared with those of class I after adjusting these parameters. Compared with the cases of class I, those with a class III showed significant attenuation in the symptoms and conditions (95 % CI: 0.034, 0.365; P < 0.001), after adjusting the age at initial correction, being informed upon diagnosis after birth, and utilization of auricle correction system. There were no statistical differences between class II and III in the treatment efficiency after correction. CONCLUSIONS: The Amazing Ear Correction System was effective in treating constricted ear, yielding satisfactory treatment efficiency. Patients with class II constriction required longer treatment time compared with those of class I. The treatment outcome in the class I constriction was better than that of class III.

Effect of External Ear Deformity on Hearing in Wrestlers.

PURPOSE: Cauliflower ear in wrestlers can lead to hearing impairment. This study primarily aims to assess the hearing of wrestlers with bilateral cauliflower ears and determine their external ear canal (EEC) resonance frequencies. Our second aim is to evaluate their hearing quality, speech, and spatial perception. METHOD: This study included 28 male wrestlers aged 18-35 years with bilateral cauliflower ears, as well as 27 male participants in the control group with no wrestling history. The participants' hearing thresholds were determined across the frequency range of 125-16000 Hz for air-conduction and 500-4000 Hz for bone conduction. EEC resonance frequencies were measured. Additionally, all participants completed the Turkish version of the Speech, Spatial, and Qualities of Hearing Scale (SSQ) questionnaire. RESULTS: Wrestlers with cauliflower ears exhibited significantly higher hearing thresholds, particularly at frequencies above 4000 Hz (p < .05). Analysis of EEC resonance showed a shift to higher frequencies in the second resonance peak of the right ear (p < .001) and the first resonance peak of the left ear (p = .045). SSQ scores revealed that wrestlers had higher spatial perception (p = .046), hearing quality (p = .004), and general scores (p = .042) in comparison to the control group. CONCLUSIONS: Blunt traumas in wrestlers, leading to cauliflower ear, can result in hearing loss. Moreover, deformities in the external ear affect the resonance frequencies of the EEC. Therefore, it is crucial to advocate for the use of ear protection equipment among wrestlers. When fitting hearing aids, attention should be given to changes in the EEC resonance frequency.

[Management of patients with complex ear deformities]. / Prise en charge des patients présentant des déformations complexes du pavillon de l'oreille.

Complex ear reconstruction requires specialized multidisciplinary care. Most patients present with microtia, often associated with hearing disorders. The management of these disorders is a priority, and reconstruction of the external ear remains optional. Nowadays, auricular reconstruction is based on the subcutaneous implantation of either autologous cartilage or an allogeneic implant. Autologous reconstruction requires highly specialized surgical expertise and involves harvesting rib cartilage but carries a lower risk of exposure compared to allogeneic implants. Both techniques yield good results with a high success rate and have a positive impact on the social functioning and daily life of patients.

La reconstruction complexe du pavillon auriculaire nécessite une prise en charge multidisciplinaire spécialisée. La majorité des patients nécessitant ce geste présentent une microtie, souvent associée à des troubles de l'audition. La prise en charge de ceux-ci est prioritaire et la reconstruction du pavillon reste facultative. Aujourd'hui, la reconstruction du pavillon se base sur l'implantation sous-cutanée d'une maquette de cartilage autologue ou d'un implant allogène. La reconstruction autologue demande une expertise chirurgicale hautement spécialisée et nécessite un prélèvement de cartilage costal mais présente un risque d'exposition inférieur par rapport à l'implant allogène. Les deux techniques permettent d'atteindre de bons résultats avec un taux de réussite élevé et un effet positif sur le fonctionnement social et le quotidien des patients.

Selecting Flap Transfer Methods to Repair Helix Soft Tissue Defect Based on the Direction of Long Axis.

BACKGROUND: The posterior auricular flap has long been favored for repairing skin defects on the ear's surface. However, achieving optimal esthetic outcomes in ear reconstruction requires a flexible approach to flap transfer methods. While bipedicle advancement flaps are commonly used for body wound coverage, they are rarely used in auricular defect repair. OBJECTIVE: To propose a modified flap transfer approach based on the orientation of the auricular defect's long axis and assess the postoperative esthetic outcomes. METHODS: The authors reported 12 patients treated using 2 distinct flap transfer techniques. Mild to moderate helix soft tissue defects remained after excision of the masses. A direct island flap was created for patients with longitudinal defects to cover the defect. For patients with transverse defects, a combination of bipedicle and island flaps was used for repair. Scar quality and esthetic outcomes were assessed at least 6 months postsurgery using the Scar Cosmesis Assessment and Rating scale. RESULTS: All patients experienced no serious complications and achieved excellent cosmetic results. Patients undergoing combined flap transfer exhibited relatively more favorable esthetic outcomes. CONCLUSION: The authors propose a novel concept for repairing helix soft tissue defects by designing local flaps based on the direction of the defect's long axis. For repairing helix soft tissue defects with a long axis parallel to the auricular edge, the combined utilization of bipedicle advancement flap and island rotation flap transfer should be consideration more.

Efficacy and Safety of Excision Combination Therapies for Earlobe Keloids: A Systematic Review and Meta-analysis.

BACKGROUND: Different combinations of excision and adjuvant therapies have been applied to improve outcomes for earlobe keloids, though evidence in this field is still lacking. OBJECTIVES: This study sought to systematically investigate efficacy and safety of these treatments. METHODS: We conducted a systematic search on PubMed, Embase, Web of Science, and Cochrane Library to find all relevant studies. Meta-analysis of recurrence rates (RRs) and adverse event rates with 95% confidence intervals, and individual participants data (IPD) were calculated for each intervention when possible. Otherwise, narrative syntheses were performed. RESULTS: A total of 85 articles, covering 23 treatments for earlobe keloids, were included, indicating a preference for multiple combination therapy. The estimated RRs for 6 interventions (i.e., excision monotherapy, combinations of excision with imiquimod, pressure therapy, radiotherapy, steroids, and steroids with pressure therapy) appeared to be comparable. Electron radiotherapy was found to have potential advantages over X-ray treatment, contributing to the observed heterogeneity. Further meta-analysis using IPD revealed that both combination therapies of excision plus steroid therapy (p=0.003) and excision plus radiotherapy (p=0.003) yielded better recurrence-free survival compared to excision alone. The median recurrence-free interval for combination therapy was 10 months. Adverse event rates were similar among different intervention groups. CONCLUSIONS: This study suggests that combining excision with radiotherapy or perioperative steroid therapy has the potential to improve prognosis of earlobe keloids without increasing the risk of adverse events. Overall evaluation of patients' conditions and further studies with sufficient follow-up are warranted for clinical practice. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Early Non-Surgical Treatment For Microtia Types 1 and 2.

Esthetic concerns and psychosocial distress often accompany auricular deformities and malformations in both children and their parents. Approximately 30% of newborns are affected by auricular anomalies, with 15% to 20% resulting in permanent defects. While surgical intervention is typically considered the gold standard for malformations, a non-surgical approach, such as splinting, molding, or other non-invasive techniques, can effectively address deformations if promptly administered by a specialist. Microtia, classified into 4 types, presents challenges ranging from fundamental structural anomalies in types 1 and 2 to severe defects in type 3 and complete absence of the external ear in type 4 (anotia). This study introduces a novel non-invasive treatment modality for microtia types 1 and 2. The cohort consisted of 5 newborns treated for microtia types 1 or 2 between 2022 and 2023. Utilizing the EarWell system, treatment was initiated before 3 weeks of age (mean age: 2 weeks), with an average treatment duration of 6.6 weeks, supplemented by molding treatment as needed. Minor adverse effects, such as simple dermatitis, were observed in 2 patients. All parents expressed high satisfaction with the esthetic outcomes, with 60% reporting extreme satisfaction. The prompt initiation of the treatment protocol for microtia types 1 and 2 led to outstanding and timely outcomes in infants, enhancing the quality of life for both parents and their children. Early intervention for subsequent treatment may improve the condition and, in certain cases, serve as a satisfactory alternative for parents hesitant about further surgical intervention for their children.

Epidemiology of congenital malformations of the external ear in Hunan Province, China, from 2016 to 2020.

To describe the epidemiology of congenital malformations of the external ear (CMEE). Data were obtained from the Birth Defects Surveillance System in Hunan Province, China, 2016 to 2020. The prevalence of CMEEs is defined as the number of cases per 1000 fetuses (births and deaths at 28 weeks of gestation and beyond) (unit: ‰). Prevalence and 95% confidence intervals (CI) were calculated by the log-binomial method. Chi-square trend tests (χ2trend) were used to determine trends in prevalence by year. P < .05 was considered statistically significant. Crude odds ratios (ORs) were calculated to examine the association of sex, residence, and maternal age with CMEEs. Our study included 847,755 fetuses, and 14,459 birth defects were identified, including 1227 CMEEs (accounted for 8.49% of birth defects). The prevalences of birth defects and CMEEs were 17.06‰ (95%CI: 16.78-17.33) and 1.45‰ (95%CI: 1.37-1.53), respectively. A total of 185 microtia-anotias were identified, accounting for 15.08% of CMEEs, with a prevalence of 0.22‰ (95%CI: 0.19-0.25). And 1042 other CMEEs were identified, accounting for 84.92% of CMEEs. From 2016 to 2020, the prevalences of birth defects were 18.20‰, 18.00‰, 16.31‰, 16.03‰, and 16.47‰, respectively, showing a downward trend (χ2trend =8.45, P < .01); the prevalences of CMEEs were 1.19‰, 1.62‰, 1.80‰, 1.21‰, and 1.35‰, respectively, with no significant trend (χ2trend =0.09, P = .77). CMEEs were more common in males than females (1.60‰ vs 1.27‰, OR = 1.26, 95%CI: 1.12-1.41), in urban areas than in rural areas (1.77‰ vs 1.23‰, OR = 1.45, 95%CI: 1.29-1.62). The prevalences of CMEEs for maternal age < 20, 20-24, 25-29, 30-34, and ≥ 35 were 1.75‰, 1.27‰, 1.44‰, 1.47‰, and 1.58‰, respectively, with no significant difference (P > .05, reference: 25-29). Most CMEEs were diagnosed by clinical examinations (92.34%), and most CMEEs were diagnosed postpartum (within 7 days) (96.25%). In summary, we have presented the epidemiology of CMEEs in Hunan Province, China. CMEEs were more common in males than females, in urban areas than rural areas, whereas there was no significant difference in prevalence of CMEEs by maternal age. We inferred that CMEEs may be mainly related to genetics, and the mechanism needs to be examined in the future.