Integrating vascularity into the pattern classification of pilomatricomas on ultrasound provides a more competent approach for discriminative evaluation.

BACKGROUND: Pilomatricoma has various manifestations on color Doppler ultrasound, and a differential diagnosis is challenging. The objective of this study was to investigate which characteristics of skin lesions on color Doppler ultrasound are effective in distinguishing pilomatricoma from epidermoid cyst and dermatofibrosarcoma protuberans. MATERIALS AND METHODS: Records of patients with pilomatricomas (n = 63), epidermoid cysts (n = 76), and dermatofibrosarcoma protuberans (n = 19) who underwent color Doppler ultrasound evaluation and surgical excision were reviewed. The anatomical distribution and color Doppler ultrasound characteristics of these lesions were analyzed. The 63 pilomatricomas were categorized into five types based on their color Doppler ultrasound characteristics, and the roles of these five types in the differential diagnosis of the aforementioned diseases were studied. RESULTS: Pilomatricomas, epidermoid cysts, and dermatofibrosarcoma protuberans exhibited some similar characteristics. Dominantly markedly hyperechoic or hyperechoic appearance, posterior acoustic shadowing, and the presence of vascularity were the major characteristics of pilomatricomas. The pilomatricomas could be categorized into five types, with type II having a diagnostic performance of sensitivity of 65.08%, specificity of 98.95%, area under the receiver operating characteristic curve (AUC) of 0.743, positive predictive value of 97.62%, and negative predictive value of 81.03% for the diagnosis of the aforementioned skin diseases. CONCLUSION: A combination of dominantly markedly hyperechoic or hyperechoic appearance, posterior acoustic shadowing, and the presence of vascularity exhibits higher diagnostic performance for the differential diagnosis of pilomatricomas, epidermoid cysts, and dermatofibrosarcoma protuberans.

Spontaneous regression of an epidermoid cyst in a pediatric patient-Case report and review of the literature.

Epidermoid cysts are infrequent, benign, slow-growing, space-occupying lesions that account for 0.5-1.8% of primary intracranial tumors. We report the case of a 17-month-old child who presented in 2015 for one episode of pallor associated with hypotonia. Epilepsy was excluded and MRI was recommended. The MRI was performed and there were no focal parenchymal lesions, but it showed an extra-axial ovoid lesion with imaging characteristics consistent with epidermoid cyst. Follow-up MRI at one year was performed and it showed minimal increased in dimensions of the cyst, without changes into the signal of the lesion. Another MRI was performed 7 years after and it showed complete resolution of the cyst. Six months afterwards, another MRI was performed and it confirmed the complete regression of the cyst, without any extra-axial masses reported. The patient did not present any neurological anomalies. No follow-up MRI was recommended afterwards. Spontaneous regression of epidermoid cyst in pediatric population is an extremely rare event, but it should be taken into account when the patient shows no symptoms. This is the third case of spontaneous regression of an epidermoid cyst reported in pediatric patients, and the first one in the temporal region. Careful follow-up and watchful waiting could be an option to surgical treatment in epidermoid cysts.

Atypical epidermoid cyst of the fourth ventricle with minimal diffusion-restriction.

BACKGROUND: Epidermoid cysts are benign, slow growing extra-axial lesions most commonly found in the cerebellopontine angle that have a characteristic imaging pattern of restricted diffusion on diffusion-weighted imaging (DWI). METHODS: A 10-year-old male with a history of asthma and diabetes was found to have a lesion within the fourth ventricle on a magnetic resonance imaging (MRI) brain study. MRI showed a well-circumscribed vermian lesion without contrast enhancement or restricted diffusion with mild hydrocephalus. He was referred to the neurosurgical service once he acutely developed symptoms of dizziness. He underwent a gross-total resection of the lesion on which histopathology confirmed an epidermoid cyst. RESULTS: Here, we report a case of an atypical epidermoid cysts found in the midline of the fourth ventricle without restricted diffusion on MRI. CONCLUSION: Avid restricted-diffusion on DWI is usually pathognomonic for an epidermoid cyst when evaluating an extra-axial lesion, yet we report the second case in the literature of an epidermoid cyst without this classical imaging characteristic.

Perineal Squamous Cell Carcinoma Arising in an Epidermal Cyst.

A 90-year-old Japanese woman who had been aware of a subcutaneous mass on the right perineal region for 5 years was referred to our hospital for further examination and treatment because of the rapid growth of the mass and bleeding that began 3 months earlier. A biopsy of the mass revealed a diagnosis of well-differentiated squamous cell carcinoma. On preoperative examination, the tumor was 90×40 mm in size and was suspected to have partially invaded the levator ani muscle and external sphincter. Since a preoperative cardiac evaluation indicated severe aortic stenosis, we performed transcatheter aortic valve implantation. A radical resection was then performed with general anesthesia. The skin and subcutaneous tissue defects were reconstructed with a posterior gluteal-thigh propeller flap, and a sigmoid colostomy was created. The patient had a good postoperative course and was transferred to a rehabilitation facility 28 days after the surgery. Epidermal cysts are a common benign tumor, and clinicians should keep in mind that these cysts can become malignant.

Neurobrucellosis presenting as an infected cerebellopontine cistern epidermoid cyst.

Neurobrucellosis is a rare complication of brucella infection which presents as meningitis, meningoencephalitis, subdural empyema, brain abscess, myelitis, and radiculo- neuritis. We report the first case of neurobrucellosis presenting as an infected cerebellopontine cistern epidermoid cyst in a young immunocompetent male who presented with fever and acute raised intracranial pressure. MRI brain showed an extra-axial mass in the right cerebellopontine angle cistern with peripheral rim enhancement and diffusion restriction. Emergency surgery unveiled a well-encapsulated lesion containing thick pus and keratinous material, confirming an infected epidermoid cyst. Intriguingly, the culture revealed Brucella infection, but the source of the infection remained unclear.

Clinical analysis of 23 cases of epidermoid cyst of testis in children.

OBJECTIVE: This study aims to examine the clinical characteristics and surgical management of pediatric testicular epidermoid cysts, thereby contributing to the existing body of knowledge pertinent to the diagnosis and therapeutic intervention s for this condition. METHODS: A retrospective analysis was conducted on the clinical records of 23 pediatric patients diagnosed with testicular epidermoid cysts, who were admitted to our institution between April 2013 and February 2024. Concurrently, a comprehensive review and analysis of pertinent literature were undertaken to augment the findings. RESULTS: The mean age at which the onset of epidermoid cysts was observed was 6.0 years. All cases were singular and unilateral. B-ultrasound diagnosis categorized 6 cases as epidermoid cysts, 11 as teratomas, and 6 as indeterminate, yielding a diagnostic sensitivity of 26.1%. All patients underwent testicle-sparing mass resection, and nine patients underwent rapid intraoperative frozen section analysis, revealing eight cases of testicular epidermoid cysts and one teratoma, with a diagnostic sensitivity of 88.89%. Postoperative histopathological examination confirmed the diagnosis of testicular epidermoid cyst. CONCLUSIONS: Pediatric testicular epidermoid cysts are an uncommon occurrence, primarily presenting as a painless scrotal mass, which can mimic the clinical features of malignant testicular tumors. Imaging modalities and histopathological assessment are pivotal in the diagnostic process for pediatric testicular epidermoid cysts. For cases where B-ultrasound is inconclusive, rapid intraoperative pathological examination should be considered.

Congenital Intraoral Dermoid and Epidermoid Cyst with Orocutaneous Fistula Presenting with Life-threatening Airway Obstruction in an Infant.

Dermoid cysts and epidermoid cysts in the floor of the mouth are rare in the pediatric age group. In this case report, we have discussed the presentation, management, and literature review of a 6-month-old female child presenting with both dermoid and epidermoid cysts in the floor of the mouth with an orocutaneous fistula.

Spontaneous regression of white epidermoid cyst of the pre-bulbar cistern in a 3-year-old child: a case report and literature review.

We describe the first case of regression of a white epidermoid cyst in a child. White epidermoid cysts are rare benign lesions, particularly in pediatric cases. Typically, these cysts need surgical resection. However, we report the case of a 3-year-old child with recurrent aseptic meningitis, in whom CT scan and MRI revealed a white epidermoid cyst in the pre-bulbar cistern. Surprisingly, over a 5-year follow-up period, the cyst showed dramatic regression without any symptoms. This case sheds light on the potential for spontaneous regression of white epidermoid cysts in children, challenging the need for risky surgical interventions. This report opens up new perspectives on the pathophysiology and management options for this type of lesion in children.

Fully neuroendoscopic resection of cerebellopontine angle tumors through a retrosigmoid approach: a retrospective single-center study.

The objective of this study is to preliminarily investigate the surgical safety, efficacy, techniques, and clinical value of fully neuroendoscopic surgery for the resection of cerebellopontine angle (CPA) tumors via a retrosigmoid approach. The clinical data of 47 cerebellopontine angle area (CPA) tumors that were treated by full neuroendoscopic surgery from June 2014 to June 2023 were retrospectively analyzed. The efficacy and advantages of the surgical techniques were evaluated based on indicators such as duration of the surgery, neuroendoscopic techniques, intraoperative integrity of nerves and blood vessels, extent of tumor resection, outcomes or postoperative symptoms, and incidence of complications. The 47 cases of cerebellopontine angle tumors include 34 cases of epidermoid cysts, 7 cases of vestibular schwannomas, and 6 cases of meningiomas. All patients underwent fully neuroendoscopic surgery. Twenty tumors were removed using the one-surgeon two-hands technique, and 27 tumors were removed using the two-surgeons four-hands technique. The anatomical integrity of the affected cranial nerves was preserved in all 47 cases. None of the patients suffered a postoperative hemorrhage, cerebrospinal fluid leak, and aseptic or septic meningitis, or died. The rate of total tumor resection was 72.3% (34/47), and the symptom improvement rate was 89.4% (42/47). All patients were followed up for 2 to 12 months, and none died nor showed any signs of tumor recurrence. By analyzing 47 fully neuroendoscopic resections of CPA tumors using the posterior sigmoid sinus approach in our center, we believe that such method allows complete, safe, and effective resection of CPA tumors and is thereby worthy of clinical promotion.

The Value of Ultrasound for Differentiating Trichilemmal Cysts From Epidermoid Cysts.

OBJECTIVES: This study was aimed to evaluate the diagnostic performance of ultrasound (US) in differentiating trichilemmal cysts (TCs) from epidermoid cysts (ECs). METHODS: Based on clinical and ultrasound features, a prediction model was established and validated. 164 cysts in the pilot cohort and another 69 in the validation cohort diagnosed with TCs or ECs histopathologically were evaluated. The same radiologist performed all ultrasound examinations. RESULTS: For clinic features, TCs tended to occur in females compared with ECs (66.7 vs 28.5%; P < .001). In addition, TCs were prone to occur in the hairy area compared with ECs (77.8 vs 13.1%; P < .001). For ultrasound features, the internal hyperechogenicity and cystic change were more likely to appear in TCs in comparison with ECs (92.6 vs 25.5%; P < .001; 70.4 vs 23.4%; P < .001, respectively). Upon the features mentioned above, a prediction model was established with the areas under the receiver operating characteristic curves of 0.936 and 0.864 in the pilot and validation cohorts, respectively. CONCLUSIONS: US is promising for differentiating TCs from ECs and is valuable for their clinical management.

Ultrasonographic Spectrum of Cutaneous Cysts With Stratified Squamous Epithelium in Pediatric Dermatology: Pictorial Essay.

High-resolution ultrasound (HRUS) is an important diagnostic method in dermatology, especially in pediatric population. The most common type of cutaneous cysts in children corresponds to cysts with stratified squamous epithelium (CSSE). The objective is to present the different ultrasonographic appearance of histologically proven CSSE in a retrospective review. Epidermoid, milium, trichilemmal, dermoid, and pilonidal cyst and steatocystomas are included. Utility of HRUS in diagnosis of cutaneous lesions is well established. It is important to know-and stay updated-about the wide spectrum of ultrasonographic appearance of CSSE in order to avoid misleading diagnoses.

How I do it: cerebellopontine angle epidermoid cyst removal with endoscopic assistance.

BACKGROUND: Epidermoid cyst in the cerebellopontine angle (CPA) can involve numerous critical structures. Endoscopic assistance following microscopic removal via a retrosigmoid approach can expand the surgical corridor, allowing for more complete resection. METHOD: We describe in a stepwise fashion the surgical steps for the microscopic removal of an epidermoid cyst of the CPA with endoscopic assistance. CONCLUSION: Endoscopically assisted microscopic removal for CPA epidermoid cysts provides wide access to the CPA and its adjacent structures and shows to be an effective option in selected cases.

Microsurgical anatomy and pathoanatomy of the outer arachnoid membranes in the cerebellopontine angle: cadaveric and intraoperative observations.

PURPOSE: The cerebellopontine angle (CPA) is a frequent region of skull base pathologies and therefore a target for neurosurgical operations. The outer arachnoid is the key structure to approach the here located lesions. The goal of our study was to describe the microsurgical anatomy of the outer arachnoid of the CPA and its pathoanatomy in case of space-occupying lesions. METHODS: Our examinations were performed on 35 fresh human cadaveric specimens. Macroscopic dissections and microsurgical and endoscopic examinations were performed. Retrospective analysis of the video documentations of 35 CPA operations was performed to describe the pathoanatomical behavior of the outer arachnoid. RESULTS: The outer arachnoid cover is loosely attached to the inner surface of the dura of the CPA. At the petrosal surface of the cerebellum the pia mater is strongly adhered to the outer arachnoid. At the level of the dural penetration of the cranial nerves, the outer arachnoid forms sheath-like structures around the nerves. In the midline, the outer arachnoid became detached from the pial surface and forms the base of the posterior fossa cisterns. In pathological cases, the outer arachnoid became displaced. The way of displacement depends on the origin of the lesion. The most characteristic patterns of changes of the outer arachnoid were described in case of meningiomas, vestibular schwannomas, and epidermoid cysts of the CPA. CONCLUSION: The knowledge of the anatomy of the outer arachnoid of the cerebellopontine region is essential to safely perform microsurgical approaches as well as of dissections during resection of pathological lesions.

Application of intra-operative magnetic resonance imaging for intracranial epidermoid cysts.

The effectiveness and safety of intraoperative magnetic resonance imaging (iMRI) are evident from many reports over the past decade. However, these reports have mainly concerned surgeries for glioma and other intra-axial tumours, and applications of this approach for extra-axial tumours are poorly documented. We retrospectively examined three cases in which iMRI was used to assist in the removal of epidermoid cysts. T2-weighted images and diffusion-weighted images were acquired during the surgeries. The value to surgeons of images generated by iMRI, the length of interruption of surgery, and the safety of the patients were assessed. In this study, the images obtained through iMRI provided were clear representations of remnant tumours, even with a low-field system (0.4 Tesla). These images generated enough information to help surgeons decide whether to use an assistance device, such as an endoscope, to remove remnant tumours and whether further retraction of the brain was safe for patients and useful in tumour removal. Intraoperative MRI has long been thought unnecessary for surgery for tumours that are well demarcated and clearly visible under a surgical microscope; in this study, however, intraoperative MRI proved to be useful and safe for patients undergoing epidermoid cyst resection.

Giant epidermoid cyst penetrating the skull: a case report and literature review.

Intracranial epidermoid cyst is a rare pseudotumor of the nervous system, accounting for 0.2%-1.8% of all intracranial tumors. It is usually located in the cerebellopontine Angle or parasellar area, with insipid onset, slow growth and usually less than 2 cm in diameter. Giant epidermoid cysts that invade the bone have rarely been reported in the literature. Herein, we report a case of giant ECs extradural to the parietal bone, penetrating the skull and continuing to expand outward. In addition, a systematic search of four authoritative databases was conducted to collect the relevant reports of giant epidermoid cyst with diameter > 5cm for the first time, and to discuss the clinical and radiographic features of patients with giant epidermoid cyst and the influence of treatment options.

Rare association of epidermoid cyst of ovary with mucinous cystadenoma- A Case Report.

Epidermoid cyst is a rare benign neoplasm of the ovary, lined by stratified squamous epithelium, lacking skin, adnexal structures, and other teratomatous elements. On the other hand, mucinous cystadenoma is one of the most common benign ovarian neoplasm that microscopically shows cystic areas lined by tall columnar mucinous epithelium. Although its coexistence with other tumours, such as mature cystic teratoma, squamous cell carcinoma, clear cell adenocarcinoma, Brenner's tumour, serous cystadenoma, etc., have been reported, a combination of benign epidermoid cyst and mucinous cystadenoma has rarely been documented in literature. We report a case of coexistence of epidermoid cyst and mucinous cystadenoma in an ovarian cyst.

Long-term surgical oncological and functional outcome of large petroclival and cerebellopontine angle epidermoid cysts: a multicenter study.

Cranial nerve (CN) disorders are the foremost symptoms in cerebellopontine angle (CPA) and petroclival area (PCA) epidermoid cysts (EC).The aim of this work was to  assess the long-term surgical results on CN function and tumor control in these patients. We performed a retrospective cohort study about 56 consecutive patients operated on for a CPA or PCA EC between January 2001 and July 2019 in six participating French cranial base referral centers. Sixteen patients (29%) presented a PCA EC and 40 a CPA EC (71%). The median clinical and radiological follow-up was 46 months (range 0-409). Preoperative CN disorders were present in 84% of patients (n = 47), 72% of them experienced CN deficits improvement at the last follow-up consultation (n = 34): 60% of cochlear and vestibular deficits (n = 9/15 in both groups), 67% of trigeminal neuralgia (n = 10/15), 53% of trigeminal hypoesthesia (n = 8/15), 44% of lower cranial nerve disorders (n = 4/9), 38% of facial nerve deficits (n = 5/8) and 43% of oculomotor deficits (n = 3/7) improved or were cured after surgery. New postoperative CN deficits occurred in 48% of patients (n = 27). Most of them resolved at the last follow-up, except for cochlear deficits which improved in only 14% of cases (n = 1/7). Twenty-six patients (46%) showed evidence of tumor progression after a median duration of 63 months (range 7-210). The extent of resection, tumor location, and tumor size was not associated with the occurrence of new postoperative CN deficit or tumor progression. A functional nerve-sparing resection of posterior fossa EC is an effective strategy to optimize the results on preexisting CN deficits and reduce the risk of permanent de novo deficits.

Sonological Appearance of Epidermoid Cyst of the Spleen: A Rarity.

Epidermoid cyst of the spleen is a rare, benign cystic lesion of congenital origin. Although most epidermoid cysts of the spleen are asymptomatic and detected incidentally on ultrasonography, the entity needs to be included in the differential diagnosis of cystic lesion mimics of the spleen, especially in patients with left hypochondriac pain. This case report describes the typical sonological appearance of epidermoid cyst of the spleen in a 31-year-old male.

[Endoscopic transnasal approach in surgical treatment of petrous temporal bone cholesteatoma extending towards the clivus. Three clinical observations and literature review]. / Endoskopicheskii transnazal'nyi dostup v khirurgicheskom lechenii kholesteatom piramidy visochnoi kosti, rasprostranyayushchikhsya v oblast' skata. Tri klinicheskikh nablyudeniya i obzor literatury.

Petrous temporal bone Cholesteatoma is widely described in the literature and accounts for up to 9% of all neoplasms of this localization. These cholesteatomas rarely spread towards the clivus. Isolated clival cholesteatomas are described only as single cases. There is currently no consensus on the choice of surgical approach for resection of similar neoplasms. OBJECTIVE: To demonstrate the possibilities of endoscopic transnasal approach in surgery for clival and petrous cholesteatoma. MATERIAL AND METHODS: This article presents 3 clinical cases: 2 patients with apical cholesteatoma of petrous part of temporal bone extending to the clivus and 1 patient with massive petrous temporal bone cholesteatoma extending towards the clivus according to the classification of Sanna M. All patients underwent endoscopic transnasal surgery. RESULTS AND CONCLUSION: In our opinion, endoscopic transnasal approach is optimal for resection of similar neoplasms. Total and subtotal resection was performed in 2 and 1 case, respectively. However, there are certain limitations of this approach in accessing the most lateral parts of the neoplasm. Nevertheless, endoscopic transnasal approach ensures resection of petrous temporal bone cholesteatoma extending to the clivus without the risk of damage to acoustic-facial cranial nerves. It is especially significant in patients without their baseline dysfunction.

Cecal epidermoid cyst: a neonatal case with clinicopathological consideration.

BACKGROUND: Only 10 cases of cecal epidermoid cyst (CEC) have been reported in the literature. Furthermore, its pathogenesis remains unclear. We report a rare case of congenital CEC in neonate, and discuss its clinicopathological findings. CASE PRESENTATION: A cystic lesion was incidentally identified in the retroperitoneal area of the abdominal right lower quadrant during a routine prenatal ultrasonography (US), prompting an ileocolectomy 3 days after birth. This congenital cyst was composed of mucosal lining cells and submucosal connective tissues, and the inner lining mucosa was composed of stratified squamous epithelium and focally mucin-producing ciliated epithelium. Based on the macroscopic and microscopic findings, the cystic lesion was diagnosed as a congenital cecal epidermoid cyst. CONCLUSIONS: The management of a fetal abdominal mass should be tailored individually, considering that epidermoid cysts can occur in the cecum during the perinatal period. We report the clinicopathological findings in this case, including its possible pathogenesis.