Advanced Diagnostic Techniques in Obstructive Sleep Apnea.

Optimal surgical and medical management of obstructive sleep apnea (OSA) requires clinically reliable identification of patterns and sites of upper airway obstruction. A wide variety of modalities has been used to evaluate upper airway obstruction. Drug-induced sleep endoscopy (DISE) and cine MRI are increasingly used to identify upper airway obstruction sites, to characterize airway obstruction patterns, to determine optimum medical and surgical treatment, and to plan individualized surgical management. Here, the authors provide an overview of the applications of DISE and cine MRI in assessing upper airway obstruction in children and adults with OSA.

Advanced Diagnostic Techniques in Obstructive Sleep Apnea.

Optimal surgical and medical management of obstructive sleep apnea requires clinically reliable identification of patterns and sites of upper airway obstruction. A wide variety of modalities have been used to evaluate upper airway obstruction. Drug-induced sleep endoscopy (DISE) and cine MRI are increasingly used to identify upper airway obstruction sites, to characterize airway obstruction patterns, to determine optimum medical and surgical treatment, and to plan individualized surgical management. Here, we provide an overview of the applications of DISE and cine MRI in assessing upper airway obstruction in children and adults with obstructive sleep apnea.

Outcomes of Injection Laryngoplasty for Deep Interarytenoid Groove.

Introduction Deep interarytenoid groove (DIG) may cause swallowing dysfunction in children; however, the management of DIG has not been established. Objective We evaluated the subjective and objective outcomes of interarytenoid augmentation with injection in children with DIG. Methods Consecutive children under 18 years of age who underwent injection laryngoplasty for DIG were reviewed. Data pertaining to demographics, past medical history, past surgical history, and results of pre and postoperative video fluoroscopic swallow study (VFSS) were obtained. The primary outcome measure was the presence of thin liquid aspiration or penetration on postoperative VFSS. The secondary outcome measure was caregiver-reported improvement of symptoms. Results Twenty-seven patients had VFSS before and after interarytenoid augmentation with injection (IA). Twenty (70%) had thin liquid penetration and 12 (44%) had thin liquid aspiration before the IA. Thin liquid aspiration resolved in 9 children (45%) and persisted in 11 (55%). Of the 12 children who had thin liquid aspiration prior to IA, 6 (50%) had resolution of thin liquid aspiration after IA. Conclusions Injection laryngoplasty is a safe tool to improve swallowing function in children with DIG. Further studies are needed to assess the long-term outcomes of IA and identify predictors of successful IA in children with DIG.

Spectrum of swallowing abnormalities in children with Type I laryngeal cleft.

OBJECTIVES: To describe the spectrum of swallowing abnormalities in children with Type I laryngeal cleft (LC-1) and evaluate the effect of LC-1 repair on swallowing abnormalities. METHODS: A retrospective review was performed of all consecutive children who were diagnosed with LC-1. Swallowing function was evaluated pre- and post-operatively using video fluoroscopic swallow study (VFSS). VFSS reports were used to define swallowing abnormalities and to determine penetration aspiration scale (PAS) and functional oral intake scale (FOIS). Prevalence of swallowing abnormalities, PAS, and FOIS scores were compared before and after repair of LC-1. RESULTS: Fifty-seven children with LC-1 had VFSS. The majority of children (86%) had a combination of oral phase, swallow triggering, pharyngeal phase, or esophageal phase impairment. The pharyngeal phase impairment was the most prevalent abnormality (p < 0.001). Esophageal phase impairment was the least prevalent VFSS abnormality (p < 0.001). Prevalence of impaired pharyngeal phase, laryngeal penetration on thin and thick liquids, and silent aspiration was less after repair of LC-1. Fourteen patients (41%) had developmentally appropriate diet with no restrictions after surgery. Nine patients (27%) required positioning and therapy strategies while having developmentally appropriate diet. PAS score after surgery was less than PAS score prior to surgery (p < 0.001). FOIS score after surgery was not different than FOIS score before surgery. CONCLUSIONS: Multiple phases of swallowing function were impaired in the majority of children with LC-1. Prevalence of swallowing abnormalities varied in the subgroups of gender, gestational age, race, and presence of comorbidity. Swallowing function improved after repair of LC-1.

Tinnitus Triggered by a Cerebellopontine Arachnoid Cyst in an Adolescent.

BACKGROUND Tinnitus can be a symptom of a wide range of disorders. The identification and treatment of the underlying condition is essential for management of tinnitus in children. Tinnitus can occur with medical conditions other than sensorineural hearing loss. Cerebellopontine arachnoid cysts are rare and can cause tinnitus and hearing loss in adults. Tinnitus caused by an arachnoid cyst has not been reported in an adolescent. We report clinical and radiological features of a teenager with bothersome tinnitus caused by an arachnoid cyst. CASE REPORT A 14-year-old girl with unilateral tinnitus for 10 months presented to the Pediatric Otolaryngology Clinic. The loudness and duration of tinnitus had progressed gradually. Turning the head to the right induced right otalgia and tinnitus. The patient denied hearing loss, vertigo, exposure to loud noise, feeling of fullness in ear, otorrhea, facial weakness, numbness, dysphagia, changes in smell or taste, and problems with the jaw or temporomandibular joint. The focused neurological examination and head and neck examination were within normal limits. The patient had normal hearing on audiometry. T1-weighted, T2-spin-echo, T2-FLAIR, and diffusion-weighted magnetic resonance imaging sequences were obtained, revealing a right cerebellopontine angle arachnoid cyst. After arachnoid cyst marsupialization, the patient's tinnitus and otalgia resolved. CONCLUSIONS This case highlights the importance of suspecting identifiable nonauditory system disorders as causes of tinnitus in children. Thorough analysis of clinical findings and timely use of imaging is critical to prevent delay in diagnosis and treatment of children with bothersome tinnitus caused by rare medical conditions.

Prevalence of Emergence Delirium in Children Undergoing Tonsillectomy and Adenoidectomy.

Objective: Emergence delirium (ED) is associated with behavioral disturbances and psychomotor agitation, increased risk of selfinjury, delayed discharge, and parental dissatisfaction with quality of care. Otolaryngology procedures are associated with an increased risk of ED. The aims of this study were to determine the prevalence of ED in children who had tonsillectomy and adenoidectomy (T&A), assess the characteristics of children who had ED, and ascertain the recovery times of patients with ED. Methods: Charts of patients who had tonsillectomy and adenoidectomy between Jan 1, 2018 and March 26, 2020 at a tertiary children's hospital were reviewed. Data collection included demographics, body mass index, indication for T&A, Pediatric Anesthesia Emergence Delirium (PAED) score, American Society of Anesthesiologists (ASA) physical status classification, total anesthesia time, postanesthesia care phase I time, and postanesthesia care phase II time. Results: Of the 4974 patients who underwent T&A, ED occurred in 1.3% of patients. Toddlers (2.9%) and male children (1.6%) had a significantly higher prevalence of ED. Prevalence of ED was similar amongst patients with recurrent tonsillitis, patients with obstructive sleep disordered breathing, and patients with both obstructive sleep apnea (OSA) and recurrent tonsillitis. The prevalence of ED was not different amongst ASA I, ASA II, and ASA III. Males with ED had longer total anesthesia times (41 v. 34 minutes, p=0.02) and ASA I patients with ED had longer phase I times (p=0.04) in the postanesthesia care unit (PACU). There was no significant difference in total anesthesia time, phase I time, or phase II time when compared across the subgroups of gender, age, indication for T&A, severity of obstructive sleep apnea (OSA), and ASA score. Conclusions: Males, toddlers, and preschool-age children were more likely to have ED. Males with ED had longer total anesthesia times. ED was associated with longer phase I times in ASA I patients.

Assessment of Central Sleep Apnea Events in Children with Sleep-Disordered Breathing.

Purpose: To determine the prevalence of central apnea (CA) events and central sleep apnea (CSA) in children with sleep-disordered breathing (SDB) and to assess the effect of tonsillectomy and adenoidectomy (TA) on CSA in children with obstructive sleep apnea (OSA). Material and Methods. The medical charts of children with SDB were reviewed to obtain information on past medical history, polysomnography (PSG) findings, and surgical management. Counts and indexes of obstructive apnea, obstructive hypopnea, and central apnea were evaluated before and after TA. The prevalence of CSA and the effect of age, gender, obesity, and comorbid conditions on CSA were assessed in children with SDB as well as in children with PSG proven OSA. Results: Seven hundred twelve children with SDB (age range: 1 to 18 yrs, mean: 5.8 ± 3.4) were identified. CA events occurred in 640 of 712 (89.5%) patients. Of the 712 patients, 315 (44.2%) met the criteria for the diagnosis of CSA. CSA was more prevalent in toddlers and preschoolers (p < 0.001). Obese children had a higher prevalence of CSA compared to nonobese children (p < 0.001). The prevalence of CSA in patients with OSA was 45.4%. The number of CA events, CAI, and OAHI after TA was less than that of before TA (p < 0.001). Residual CSA after TA occurred in 20 children (26%). Conclusion: Central apnea events and central sleep apnea occur in children who present to a pediatric otolaryngology clinic for evaluation of sleep disordered breathing. Central sleep apnea and obstructive sleep apnea both improve after tonsillectomy and adenoidectomy.

A Fractured Tracheostomy Tube Causing Airway Compromise.

BACKGROUND A wide variety of emergency scenarios associated with tracheostomy tubes have been reported in patients with complex airway disease. Fracture of a tracheostomy tube is a rare complication with a potential for catastrophic outcome. The aim of this case report is to present clinical features and management of airway compromise due to a fractured tracheostomy tube in a patient with subglottic and tracheal stenosis. CASE REPORT A 19-year-old woman with a history of chronic lung disease, developmental delay, subglottic stenosis, and tracheal stenosis presented to the Emergency Department after her mother noticed that the tracheostomy tube was broken at the junction of the cannula and neck plate. Upon arrival, the patient was stable and the stoma site had a pinpoint-size opening. A chest X-ray revealed a dislodged tracheostomy tube with the shaft's convexity ventrally oriented in the trachea. The stoma was dilated to allow passage of a 2.5-mm flexible laryngoscope into the trachea. The fractured tracheostomy tube lodged in the trachea distal to the stoma and proximal to the carina. The fractured tracheostomy tube migrated to the suprastomal site at the time of repeat tracheoscopy under general anesthesia. The fractured tracheostomy tube was removed transorally through the tracheal and subglottic stenosis with the use of optical forceps and rigid bronchoscope. CONCLUSIONS Prompt recognition and management of a fractured tracheostomy tube is critical to prevent morbidity and mortality. Caregivers and healthcare providers must be prudent about proper tracheostomy tube care, potential manufacturing defects, and monitoring the condition of tracheostomy tubes.

Sudden anosmia and ageusia in a child: A COVID-19 case report.

OBJECTIVE: COVID-19 in children has a spectrum of clinical presentations ranging from asymptomatic infection to severe illness and death. The recognition of COVID-19 in children has been challenging due to overlap with symptoms of common respiratory and gastrointestinal tract infections. We describe isolated sudden anosmia and ageusia as an uncommon clinical presentation of a child with COVID-19. METHODS: Chart of a 17-year-old male referred to a tertiary care pediatric hospital for assessment of anosmia and ageusia was reviewed. Data included relevant history and physical examination, diagnostic work up, and management. RESULTS: The child presented with sudden anosmia and ageusia for 3 months. The patient did not have symptoms of upper respiratory tract infection or gastrointestinal infection. There was no history of trauma. Examination of the ears, nose, and throat were all unremarkable. Magnetic resonance imaging documented the presence of both olfactory bulbs and olfactory sulci. SARS-CoV-2 IgG test was positive. Anosmia was confirmed by The University of Pennsylvania Smell Identification Test with a score of 27.5%. CONCLUSIONS: The clinical picture of our patient represents a non-classical presentation of COVID-19 in a child. Clinicians should be cognizant about uncommon presentations of COVID-19 in previously asymptomatic children.

Recurrent Epistaxis and Unilateral Intranasal Mass in A Teenager.

BACKGROUND Epistaxis in children is a common problem encountered in outpatient clinics and emergency departments. A wide variety of conditions may cause recurrent epistaxis in children. We describe clinical, radiologic, and histologic features of a lobular capillary hemangioma presenting as a rapidly growing intranasal mass in a child with recurrent epistaxis. CASE REPORT A 16-year-old male presented with a 2-month history of recurrent unilateral epistaxis requiring multiple visits to the emergency department. The child had nasal obstruction, snoring, no recurrent sinus infections, no anosmia nor hyposmia, no weight loss, no night sweats, no fever, no decreased activity, and no easy bruising. He denied any history of local trauma. On physical examination, a fleshy violaceous mass was found, protruding from and obliterating the right nasal cavity. Magnetic resonance imaging documented an avidly enhancing mass centered at the right nasal vestibule. Upon resection, histologic evaluation indicated a pyogenic granuloma. At the 2-month followup, the surgical site was healed with no evidence of recurrent lesion. CONCLUSIONS Lobular capillary hemangioma, although uncommon, should be considered in the differential diagnosis of recurrent epistaxis and intranasal mass in children.

The Effect of Tonsillectomy and Adenoidectomy on Isolated Sleep Associated Hypoventilation in Children.

OBJECTIVE: Sleep associated hypoventilation (SAH) is diagnosed when more than 25% of total sleep time (%TST) is spent with end tidal carbon dioxide (EtCO2 ) > 50 mmHg. SAH in children occurs as a single entity or combined with obstructive sleep apnea. Outcomes of surgical treatment for isolated SAH in children have not been reported. METHODS: The medical charts of children who were diagnosed with isolated SAH and did not have OSA at a tertiary children's hospital between January 2013 and December 2019 were reviewed. Data collection included information on history and physical examination, past medical history, polysomnography (PSG) findings, and surgical management. RESULTS: Seventeen children (10 male, 7 female, age range: 3-14 years) were diagnosed with isolated SAH. Comorbid conditions included asthma in four children, Down syndrome in one, and seizure in two. Eight children were normal weight, four were overweight, and five were obese. Children did not have obstructive or central sleep apnea. Three children (18%) had persistent SAH as documented by PSG. All normal weight children had resolution of SAH whereas two obese children and one overweight child had residual SAH. %TST with CO2 > 50 mmHg after upper airway surgery (3.4% ± 1.6%) was significantly less than that of before TA (59.1% ± 5.5%) (P < .001). CONCLUSIONS: The majority of children with isolated SAH had normalization of hypercapnia after TA. Further studies in larger groups of children are needed to identify the risk factors for residual isolated SAH after TA. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1380-E1382, 2021.

Comparative assessment of drug-induced sleep endoscopy scoring systems in pediatric sleep apnea.

OBJECTIVES/HYPOTHESIS: A wide variety of drug-induced sleep endoscopy (DISE) scoring systems has been used to evaluate sites of upper airway obstruction in children and adults; however, a universally accepted DISE scoring system dedicated to children has not been developed. We evaluated the utility of DISE scoring systems in the assessment of obstructive sleep apnea (OSA) using a single cohort of pediatric patients. STUDY DESIGN: Retrospective chart review. METHODS: The medical records of surgically naïve-healthy children with OSA who had undergone DISE were reviewed. Information about demographics, past medical history, and severity of OSA were obtained. A literature review was conducted to identify DISE scoring systems used in children with OSA. Recordings of DISE were analyzed without knowledge of patient information and severity of OSA. The effect of age, obesity, severity of OSA, and oxygen nadir on DISE score was assessed. RESULTS: Sixty-eight patients (46 male, 22 female, age range: 19 months-18 years) were included. Forty-three patients were obese and 25 were nonobese. The severity of OSA was mild in 12 patients, moderate in 13 patients, and severe in 43 patients. DISE scoring systems did not document differences among the groups of patients with mild OSA, moderate OSA, and severe OSA (P > .05). DISE scores were not different among the studied age and weight categories (P > .05). CONCLUSIONS: The DISE scoring systems did not show differences in DISE scores in surgically naïve-healthy children with varying age, weight, and OSA severity categories. Our findings provide preliminary evidence for the need of a universally applicable pediatric DISE scoring system for OSA. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:2195-2198, 2019.

An uncommon source for oesophageal foreign body: Fidget spinner.

Fidget spinner is a new handheld toy with potential choking and ingestion hazard. Our objectives are to describe clinical presentation of a child with fidget spinner ingestion and draw attention to danger associated with fidget spinner. A 3-year-old boy presented with painful swallowing and feeling of something stuck in the throat. A chest radiograph revealed a radiopaque foreign body with a disc-like component. Rigid oesophagoscopy revealed a foreign object with disc battery and battery holder circuit board. Clinicians should consider the fidget spinner as one of many varieties of toys that has potential for button battery ingestion or aspiration.

Subcutaneous Lobular Capillary Hemangioma Presenting as a Facial Mass.

Lobular capillary hemangioma is a benign lesion of the skin and mucous membranes. Subcutaneous lobular capillary hemangioma presents as a deeper nodule. Lack of the characteristic surface changes of this subtype of lobular capillary hemangioma makes the clinical diagnosis challenging. We describe clinical, radiologic, and histological features of a subcutaneous lobular capillary hemangioma tissue presenting as a facial mass in a 12-year-old male. The mass was a firm, nontender, immobile, subcutaneous nodule, with no color change of the overlying skin. CT imaging documented a hyperdense and nonlipomatous mass involving soft tissue of the left lateral nasal wall. An excisional biopsy was performed. Histologic evaluation showed subcutaneous lobular capillary hemangioma. Subcutaneous lobular capillary hemangioma, although uncommon, should be considered in the differential diagnosis of lateral nasal wall mass in children.

A rare cause of tonsil mass in a child: Lymphoid polyp.

OBJECTIVE: Solitary mass lesions of the palatine tonsils are rare in children. While a tonsillar mass can be concerning for a neoplasm, benign conditions may present with a mass arising from the surface of the palatine tonsils in children. We describe clinical and histopathological characteristics of a lymphoid polyp in a child with unilateral tonsillar mass. METHODS: Retrospective chart review. RESULTS: A 6-year-old girl presented for evaluation of recurrent acute tonsillitis and a mass on the left palatine tonsil. A pedunculated mass with the base attached to the left palatine tonsil was observed. The mass was completely removed by tonsillectomy. The final diagnosis was lymphoid polyp. CONCLUSION: Pediatricians, otolaryngologists, and pathologists should be aware of the occurrence of tonsillar lymphoid polyp in the pediatric age group.

The current state of pediatric drug-induced sleep endoscopy.

OBJECTIVES/HYPOTHESIS: The purpose of this investigation was to assess current drug-induced sleep endoscopy (DISE) practice patterns at centers that have published on the technique, to identify areas of agreement, and to identify areas of disagreement that may represent opportunities for improvement and standardization. STUDY DESIGN: Multi-institutional survey. METHODS: A survey was designed in two phases to evaluate preoperative assessment, intraoperative performance, and postoperative management of patients undergoing DISE. The survey was constructed iteratively in consultation with the all of the coauthors, each selected as an expert owing to their previous publication of one or more articles pertaining to pediatric DISE. In the first phase of survey creation, each expert was asked to provide narrative answers to questions pertaining to DISE. These responses served as the basis for a second survey. This second survey was then administered to all pediatric otolaryngologists at each respective institution. RESULTS: Overall, there was a low rate of agreement (33%) among the respondents; however, there was substantial agreement within institution, particularly for the use of anesthetic medications, the use of cine magnetic resonance imaging, and performance of bronchoscopy along with DISE. There was strong agreement among all respondents for performing DISE in a child with severe obstructive sleep apnea following adenotonsillectomy, regardless of comorbidities. CONCLUSION: This multi-institutional survey demonstrated a lack of consensus between experts and multiple opportunities for improvement. In general, there was agreement regarding the workup prior to DISE performance and the endoscopic protocol but disagreement regarding anesthetic protocol and management decisions. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:266-272, 2017.

Multimodality assessment of upper airway obstruction in children with persistent obstructive sleep apnea after adenotonsillectomy.

OBJECTIVES/HYPOTHESIS: Children with obstructive sleep apnea (OSA) may have multiple sites of upper airway obstruction (UAO). A wide variety of techniques has been used to evaluate UAO. Our aim was to compare findings of cine magnetic resonance imaging (MRI) and drug-induced sleep endoscopy (DISE) in identifying UAO sites in children with persistent OSA after adenotonsillectomy (AT). STUDY DESIGN: Retrospective chart review. MATERIAL AND METHODS: The medical records of children who underwent DISE and cine MRI were reviewed. Data pertaining to demographics, past medical history, body mass index, polysomnography, findings of DISE, and cine MRI were obtained. RESULTS: Fifteen children (11 boys, 4 girls; age range, 7-18 years) were identified. Comorbid conditions were Down syndrome in nine patients, cerebral palsy in one, attention deficit hyperactivity disorder in two, and asthma in three. Severity of OSA was moderate in five, and severe in 10. DISE and cine MRI showed the same UAO site in 10 patients: a single site (tongue) in nine and multiple sites (tongue and oropharynx/lateral walls) in one. DISE showed additional UAO sites undetected by cine MRI in three patients. Cine MRI showed additional UAO sites undetected by DISE in one patient. DISE and cine MRI showed different sites of obstruction in one patient. CONCLUSIONS: Cine MRI and DISE documented single and multiple sites of UAO in children with persistent OSA after AT. Cine MRI and DISE findings were similar in the majority of the children. Assessment of the sensitivity and specificity of cine MRI and DISE in detecting sites of UAO merits further investigation. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:1224-1230, 2017.

A rare nasal cavity mass in a child: Accessory middle turbinate.

OBJECTIVES: The accessory middle turbinate, a rare anatomical variation of the nasal cavity, have been systematically studied in adults. Presence of accessory middle turbinate and its clinical significance in a child has not been reported. We describe clinical appearance and radiologic features of accessory middle turbinate in a child. METHODS: Retrospective chart review. RESULTS: A 3-year-old boy presented to the otolaryngology clinic for evaluation of recurrent epistaxis. Anterior rhinoscopy revealed moist nasal mucosa without inflammation and bilateral prominent blood vessels on the anterior nasal septum. Nasal endoscopy showed turbinate like protuberances in bilateral middle meatus. CT images documented accessory middle turbinate in the bilateral nasal cavity. CONCLUSION: Otolaryngologists should be cognizant of anatomical variations of middle turbinate to achieve correct diagnosis and avoid potential complications during surgical management.

Risk factors for residual obstructive sleep apnea after adenotonsillectomy in children.

OBJECTIVES/HYPOTHESIS: To determine the prevalence of residual obstructive sleep apnea (OSA) in children who had adenotonsillectomy (AT) and to identify the risk factors for residual OSA after AT. STUDY DESIGN: Retrospective chart review. METHODS: Children with OSA who had AT at a tertiary care children's hospital were reviewed. Data pertaining to demographics, past medical history, body mass index, tonsil and adenoid size, and polysomnography were obtained. Residual OSA was defined as apnea hypopnea index (AHI) greater than 2. The rate of residual OSA and risk factors for residual OSA were assessed. RESULTS: One hundred sixty-nine children with OSA underwent polysomnography before and after AT. The prevalence of residual OSA was 38%. The prevalence of residual OSA in obese patients (49%) was higher than that of nonobese patients (27%) (P = .02). Patients with neurological/developmental/craniofacial abnormalities had higher prevalence of residual OSA (44%) than patients without comorbidities (33%) (P < .05). The prevalence of residual OSA in patients with severe OSA (42%) was higher than patients with moderate (29%) or mild OSA (0%) (P = .03). Teenage patients (67%) had a higher prevalence of residual OSA than toddlers (27%), preschooler (33%), and middle childhood groups (29%) (P = .03). CONCLUSIONS: The majority of children had improvement in OSA after AT. The choice of AHI threshold used to define residual OSA influenced the prevalence of residual OSA. Teenagers and children with obesity, comorbidities including neurological/developmental/craniofacial abnormalities alone or in combination with asthma, or severe OSA have a high risk of residual OSA. LEVEL OF EVIDENCE: 4 Laryngoscope, 126:2624-2629, 2016.

Pilomatricoma of Childhood: A Common Pathologic Diagnosis Yet a Rare Radiologic One.

OBJECTIVE: The purposes of this study were to determine the accuracy of radiology reports in the diagnosis of pediatric pilomatricoma and to describe the characteristic imaging findings in a large cohort. MATERIALS AND METHODS: Query of a pathology database between January 2009 and February 2014 yielded 623 specimens from 596 patients. Seventy-four patients (41 girls, 33 boys; mean age, 8.9 years) underwent imaging of the 80 excised lesions. Ninety imaging studies were available (58 ultrasound, 11 CT, 21 MRI). Radiology reports were reviewed. The lesions were evaluated for location, size, and imaging characteristics. RESULTS: Pilomatricoma was included as an indication for two (2.2%) imaging studies. No differential diagnosis was given in 34 (37.8%) imaging reports. In the radiology reports, pilomatricoma was suggested as a possibility for 12 (13.3%) lesions. Foreign body reaction (13.3%), dermoid cyst (10.0%), and sebaceous cyst (8.9%) were other leading suggested diagnoses. In six (6.7%) reports, lesions were described as aggressive tumors. In nine (10.0%) reports additional studies were recommended. In all examinations, the lesions involved both skin and subcutaneous tissues without infiltration of the deep tissues. Hypoechoic rim (82.8%), internal reticulations (65.5%), and flow at Doppler examination (63.2%) were the most common sonographic features. MRI characteristics were enhancement (100.0%), heterogeneous T2-weighted hyperintensity with intermixed hypointensity (76.2%), T1-weighted isointensity in relation to skeletal muscle (66.7%), and absence of restricted diffusion (100.0%). CONCLUSION: Although pilomatricoma is a common tumor of the skin and subcutaneous tissues, imaging is infrequently used in the diagnosis, and therefore, many radiologists are not aware of the lesion. The imaging features of pilomatricoma are consistent in all imaging modalities.