Ultrasound to differentiate thyroglossal duct cysts and dermoid cysts in children

Diagnostic accuracy of ultrasonography to distinguish thyroglossal duct cysts from dermoid cysts in children with a midline neck swelling

INTRODUCTION

Midline neck swellings are very common in children and mostly caused by thyroglossal duct cysts (TGDCs) or dermoid cysts (DCs). Since DCs can undergo simple excision, whilst TGDCs demand more thorough resection via Sistrunk procedure, it is important to differentiate between both pre-operatively. Previous studies have suggested an ultrasound-score (SIST) based on presence of septae, wall irregularity and solid components could do so. This study aims to evaluate the diagnostic accuracy of this score.

METHODS

All patients (≤18 years) undergoing surgery between 2006 and 2018 for a midline neck mass at our tertiary centre with a histopathological diagnosis of TGDC or DC were retrospectively included. The pre-operative ultrasound was evaluated by an experienced radiologist and the SIST as well as location, tract, echogenicity, margin and multilocularity were scored.

RESULTS

We included 97 children, of whom 67 (69 %) with TGDCs. The SIST showed a sensitivity of 37 %, specificity of 97 %, a positive predictive value of 96 % and a negative predictive value of 35 % for the SIST-score in detecting TGDCs, which resulted in an AUC of 0.67. In addition, internal echogenicity (P < 0.01) and margin definition (P < 0.01) were significantly associated to TGDC diagnosis whilst location and multilocularity were deemed insignificant following Bonferroni correction.

CONCLUSION

We conclude that the SIST-score seems very capable to rule in TGDC. However, the SIST-score is far from making a clear distinction between DC and TGDCs preoperatively. The addition of other ultrasound variables, such as margin definition and echogenicity, might increase the diagnostic accuracy and demands further research.

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.

Skin sonography in children: a review

Skin lesions are not uncommon in children, and most of them are benign. However, they can be a matter of concern. Although in most cases the diagnosis can be suspected based on clinical history and physical examination, in some cases clinical findings are nonspecific. High-frequency color Doppler US is a noninvasive technique that can play a relevant role in these cases and give important anatomical information for final clinical management. US can be helpful to avoid unnecessary surgery, plan a surgical excision and avoid advanced imaging studies such as MRI and CT, which have a lower resolution for the skin. Different lesions can look similar on US, and clinical correlation is always important. The purpose of this article is to show a variety of skin lesions that occur in children, emphasizing clinical-sonographic correlation, and to familiarize pediatric radiologists with the US technique and sonographic appearance of common skin lesions in children.

High-Resolution Laryngeal US: Imaging Technique, Normal Anatomy, and Spectrum of Disease

Although US is one of the most used modalities for head and neck imaging, its use in the diagnosis of laryngeal abnormalities is much less widespread. The standard assessment of laryngeal abnormalities currently involves direct laryngoscopy and cross-sectional imaging (either CT or MRI) but rarely US. US is readily available, noninvasive, and radiation free, and it allows real-time imaging (with video for dynamic assessment), higher resolution than that of cross-sectional imaging, and the performance of targeted fine needle aspiration cytology or biopsy. This modality, particularly with the advent of high-resolution US, has been found to be at least comparable to CT or MRI for diagnosis of malignant lesions and benign abnormalities such as vocal nodules, polyps, cysts, and Reinke edema. Furthermore, it has been found to be more sensitive for diagnosis of abnormalities such as small glottic tumors, and its dynamic capability can be used to identify functional abnormalities such as vocal cord palsy. The authors outline the technique of laryngeal US, which includes strategies to avoid calcified laryngeal cartilage by imaging through the thyrohyoid and cricothyroid membranes with a five-sweep strategy supplemented by cine film of the technique. They also provide US images of common laryngeal abnormalities such as tumors with and without extralaryngeal extension; vallecular, thyroglossal, and vocal cord cysts; laryngeal mucoceles; and vocal cord palsy. Online supplemental material is available for this article. ^©RSNA, 2020.

Proposed ultrasound algorithm to differentiate thyroglossal duct and dermoid cysts

OBJECTIVE

1) To assess reproducibility of the previously established SIST score. 2) To determine inter-observer agreement in using ultrasound (US) characteristics to differentiate thyroglossal duct cyst (TGDC) from dermoid cysts (DC) 3) Improve the method used to pre-operatively differentiate TGDC from DC.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care pediatric hospital. SUBJECTS AND METHODS: An electronic medical record was queried to identify children with midline neck masses who underwent pre-operative neck US and had a histopathologic diagnosis of either TGDC or DC. Two pediatric radiologists, blinded to the pathologic diagnosis, evaluated the US images and documented the presence of pre-determined characteristics of each mass. Potential differentiating factors were analyzed for their predictive power. The SIST (septations, irregular walls, solid components = TGDC) score was determined as well as inter-observer agreement. Using the characteristics that had significant predictive power, we used the data to develop an algorithm to improve predicting cyst type.

RESULTS

Pathologically, there were 47 TGDC and 25 DC. The inter-observer agreement about the pathologic diagnosis between the two radiologists was substantial, K = 0.66. Overall, the SIST score predicted the correct diagnosis 67% of the time. Radiologist 1 and radiologist 2 were more accurate than the SIST score alone, making the correct diagnosis 96% and 86% of the time, respectively. In our study, we found that the most important US characteristics in differentiating TGDC and DC are: internal Septations, depth relative to Strap muscles, Shape and Solid parts (4 S algorithm). The SIST score criteria were individually shown to be significant and sensitive in recognizing DC, however, they were not specific and often misclassified TGDC as DC. We developed a new sequential filtering algorithm that more accurately differentiates cysts. This new algorithm uses step-wise filtering of characteristics, first for Septations, then for depth to Straps, then Shape of the cyst and lastly Solid parts (4 S algorithm). This algorithm correctly categorized cyst type in 100% of patients in our study.

CONCLUSIONS

Pre-operatively differentiating TGDC and DC continues to be a challenge. Using our 4 S algorithm, we can more definitively differentiate TGDC from DC compared to the SIST score. All SIST score characteristics were significant and sensitive in detecting dermoid cysts, however, not very specific. The radiologists' judgment and accuracy was better than the SIST score. The 4 S algorithm uses sequential filtering of important characteristics: Septations, depth to Straps, Shape of cyst and lastly Solid parts to improve diagnostic accuracy.

Cutaneous ultrasound and its utility in Pediatric Dermatology: Part II-Developmental anomalies and vascular lesions

High-frequency ultrasonography represents a promising tool for pediatric dermatologists. It is a noninvasive and harmless diagnostic technique that is especially appealing when working with children. It can be easily performed at the patient's bedside, avoiding diagnostic delays, sedation, or multiple visits. It represents a useful adjunct to clinical examination and aids our understanding of cutaneous pathology. In this second part, we describe the ultrasonographic findings of developmental anomalies and vascular lesions.

Subcutaneous dermoid cysts on the eyebrow and neck

We report a case of dermoid cysts on the right lateral eyebrow and anterior neck. Multiple concurrent dermoid cysts, as in the present case, are very rare. The differential diagnosis of dermoid cyst includes epidermoid (epidermal inclusion) cyst, trichilemmal cyst, pilomatrixoma, lymphatic malformation, and lipoma. In particular, thyroglossal duct cyst and midline anterior neck inclusion cyst are part of the differential diagnosis when the lesion is in the anterior neck.

Differentiation of sublingual thyroglossal duct cyst from midline dermoid cyst with diffusion weighted imaging

PURPOSE

to differentiate sublingual thyroglossal duct cyst (TGDC) from midline dermoid cyst (DC) with diffusion weighted imaging (DWI).

MATERIALS AND METHODS

Retrospective analysis of 22 consecutive patients (11 male and 11 female aged 5-15 years) with midline cystic lesion at floor of mouth. They underwent DWI of floor of mouth. Apparent diffusion coefficient (ADC) of the cystic lesions was calculated and correlated with surgical findings.

RESULTS

The mean ADC value of TGDC of 1st observer was (2.20 ± 0.28 × 10^-3 mm²/s) and of 2nd observer was (2.28 ± 0.27 × 10^-3 mm²/s) was significantly higher than that of DC (P = 0.001) whose ADC of 1st observer was (1.55 ± 0.15 × 10^-3 mm²/s) and of 2nd observer was (1.53 ± 0.11 × 10^-3 mm²/s). There was excellent inter-observer agreement of both readings (r = 92%, P = 0.001). When ADC of 1.76 and 1.62 × 10^-3 mm²/s was used as a threshold value for differentiating TGDC from DC, the best results were obtained with area under the curve of 0.94 and 0.96, accuracy of 90% and 86%, sensitivity of 91% and 91%%, specificity of 90% and 80%, negative predictive value of 90% and 88% and positive predictive value of 92% and 84% of both reviewers respectively.

CONCLUSION

DWI is reliable and reproducible imaging modality for differentiation sublingual TGDC from DC.

Preoperative ultrasound for the diagnosis of thyroglossal duct cysts: A validation study

OBJECTIVES

To evaluate the use of ultrasound to distinguish between thyroglossal duct cysts (TGDC) and dermoid cysts (DC) for surgical planning. To validate the SIST (septae + irregular wall + solid components = TGDC) scoring system proposed by Oyewumi et al. [1].

METHODS

This was a retrospective chart review of pediatric patients with midline neck masses who presented between the years of 2005 and 2014 and underwent preoperative ultrasound and surgical resection. Two pediatric radiologists blinded to diagnosis reviewed each US for 14 separate characteristics. According to the SIST scoring system, one point was given for each of the following: internal septae, irregular walls, and solid components.

RESULTS

45 patients met inclusion criteria. Final pathologic diagnosis showed 29 patients had TGDC, 16 had DC. The majority of patients with both TGDC and DC earned SIST scores of 0.

CONCLUSION

While ultrasound remains a useful part of the work-up of lesions of the head and neck in children, this small retrospective study was not able to validate the previously proposed SIST scoring system None of the parameters discussed in the original paper was found to be a statistically significant determinant of TGDC.

Diagnostic Accuracy of Midline Pediatric Neck Masses

Objective

To assess clinical evaluation, ultrasound, and previously published predictive score at preoperatively diagnosing midline neck masses and demographic or clinical associations that aid in differentiation of thyroglossal duct and dermoid cysts.

Study Design

Retrospective chart review.

Setting

Tertiary care children’s hospital.

Subjects

Patients <18 years undergoing primary midline neck mass surgery with histopathologic diagnosis of thyroglossal duct or dermoid cyst who had preoperative ultrasound performed were included.

Methods

An electronic medical record query generated 142 patients whose histopathologic diagnosis was thyroglossal duct cysts (TGDCs) or dermoid cysts (DCs). Charts were reviewed for demographic and clinical features. A radiologist blindly reviewed patients’ ultrasounds for SIST (septae + irregular walls + solid components = thyroglossal) score components. Each patient received 3 preoperative diagnoses: clinical, ultrasound, and SIST. Statistical analyses were conducted to determine association of demographic, clinical, or radiographic variables with diagnoses. Specificity, sensitivity, and predictive values were evaluated for each candidate diagnosis.

Results

There were 83 TGDCs and 59 DCs. Tenderness, infection history, depth relative to strap muscles, and SIST components were more common among TGDCs. Sensitivity and positive and negative predictive values surpassed 63% for each diagnostic modality. SIST score outperformed other diagnostic modalities with sensitivity, positive predictive value, and negative predictive value of 84%, 91%, and 81%, respectively. Clinical and ultrasound assessments were largely inconclusive for dermoid cysts, but SIST correctly identified 89% of DCs.

Conclusion

SIST score was the most accurate predictor of pediatric midline neck masses. Clinical and radiographic findings may help guide preoperative diagnosis, although further evaluation is required to develop more efficacious diagnostic tools.

The Central Neck Dissection or the Modified Sistrunk Procedure in the Treatment of the Thyroglossal Duct Cysts in Children: Our Experience

Background

The aim of the study was to present the surgical techniques providing the lowest recurrence rate in treatment of the primary and recurrent thyroglossal duct cyst (TGDC) in children.

Methods

The study included 73 patients operated on because of TGDC in years 2011-2016. Ultrasound was performed in all patients preoperatively. In 8 patients with the recurrence of the disease, the CT or MR was carried out before the surgery. Children with the primary disease underwent the modified Sistrunk procedure. In the revision cases the central neck dissection was a method of choice.

Results

In 45 children, the modified Sistrunk procedure was performed and 28 underwent the central neck dissection. In 2 patients, hematoma occurred after the modified Sistrunk procedure with the need of the surgical revision in one. No complications were observed after the central neck dissection.

Conclusions

A modified Sistrunk procedure is method of choice in the treatment of the uncomplicated TGDC. In selected cases of the TGDC with a history of infected cyst or incision of an abscess or in revision cases the central neck dissection should be considered in order to avoid the risk of the further recurrences.

The Central Neck Dissection or the Modified Sistrunk Procedure in the Treatment of the Thyroglossal Duct Cysts in Children: Our Experience

Background

The aim of the study was to present the surgical techniques providing the lowest recurrence rate in treatment of the primary and recurrent thyroglossal duct cyst (TGDC) in children.

Methods

The study included 73 patients operated on because of TGDC in years 2011–2016. Ultrasound was performed in all patients preoperatively. In 8 patients with the recurrence of the disease, the CT or MR was carried out before the surgery. Children with the primary disease underwent the modified Sistrunk procedure. In the revision cases the central neck dissection was a method of choice.

Results

In 45 children, the modified Sistrunk procedure was performed and 28 underwent the central neck dissection. In 2 patients, hematoma occurred after the modified Sistrunk procedure with the need of the surgical revision in one. No complications were observed after the central neck dissection.

Conclusions

A modified Sistrunk procedure is method of choice in the treatment of the uncomplicated TGDC. In selected cases of the TGDC with a history of infected cyst or incision of an abscess or in revision cases the central neck dissection should be considered in order to avoid the risk of the further recurrences.

Applications of 3-Dimensional Ultrasonography in the Neck, Excluding the Thyroid

Ultrasonography (US) of the neck is an accepted, useful imaging modality for many applications beyond its usefulness in thyroid disease. Two-dimensional US has been effectively used for evaluation of many types of neck conditions, and now, 3-dimensional US can be added to the imaging armamentaria. Three-dimensional US is useful in the evaluation of cervical lymph nodes, recurrent/residual thyroid neoplasia, parathyroid glands, parotid and submandibular glands, as well as thyroglossal duct cysts and other assorted palpable and visible abnormalities because of its unique capabilities, including multiplanar reconstruction, accessibility of the coronal view, volume calculation, and regularly spaced incremental slice evaluation.

Ultrasonographic features differentiating thyroglossal duct cysts from dermoid cysts

PURPOSE

The purpose of this study was to identify ultrasonographic features that can be used to differentiate between thyroglossal duct cysts (TGDCs) and dermoid cysts (DCs).

METHODS

We searched surgical pathology reports completed between January 2004 and October 2015 and identified 66 patients with TGDCs or DCs who had undergone preoperative ultrasonography. The ultrasound images were reviewed by two radiologists who were blinded to the pathological diagnosis. They evaluated the following parameters: dimensions, shape, margin, location in relation to the midline, level in relation to the hyoid bone, attachment to the hyoid bone, the depth of the lesion in relation to the strap muscles, internal echogenicity, internal echogenic dots, multilocularity, the presence of a longitudinal extension into the tongue base, posterior acoustic enhancement, the presence of internal septae, and intralesional vascularity.

RESULTS

There were 50 TGDCs and 16 DCs. TGDCs were significantly more likely than DCs to have an irregular shape, an ill-defined margin, attachment to the hyoid bone, an intramuscular location, heterogeneous internal echogenicity, multilocularity, and longitudinal extension into the tongue base.

CONCLUSION

Ultrasound findings may inform the differential diagnosis between TGDCs and DCs.

Head and neck ultrasound: technical advances, novel applications and the role of elastography

High-resolution ultrasound (US) provides superb anatomical detail in the superficial anatomy of the neck and has become the first-line imaging investigation for neck lumps and a crucial component of clinical pathways. In this article, a wide range of advances in neck US are described with a focus on the emerging role of ultrasound elastography. Selected examples of clinical utility are presented across a spectrum of scenarios with discussion of newer applications, service delivery, and training issues. The changing role of the neck ultrasound practitioner and the future of the technique in the head and neck are considered.