Plunging Ranulas and Prevalence of the "Tail Sign" in 126 Consecutive Cases

An unusual clinical presentation of a plunging ranula-The plunging ranula with extension to the vallecula

Key Clinical Message

A plunging ranula may present initially as an extensive vallecular cyst and correct diagnosis may be reached with the use of ultrasound, fluid aspiration for amylase detection, and MRI imaging.

Abstract

The ranula is a pseudocyst of the sublingual salivary gland and can be divided into two known subtypes. The simple ranula and plunging ranula. While the simple type can be found in the floor of the mouth, the plunging ranula usually pervades the mylohoid muscle and presents as a cervical swelling. The presented case should outline the difficulties in diagnostic and treatment of an uncommon expression of a mucocele above the mylohoid muscle without presenting either a cervical or an intraoral swelling, only extending towards the vallecula. We present a previously unreported clinical manifestation of a ranula of an 18-year old male, which extends posteriorly, remaining confined in the supramylohyoid muscle space. The cystic lesion protrudes in the oropharynx, and clinically appears as an extensive vallecular cyst. On magnetic resonance imaging the initial suspected diagnosis of a vallecular cyst was changed to the final diagnosis of a plunging ranula. The marsupialization of the cyst sac was performed. Outpatient follow-up revealed a persisting ostium, indicating a continuous extravasation of the sublingual gland. The present case report describes an unusual clinical presentation of a plunging ranula, remaining above the mylohyoid muscle and protruding into the oropharynx, misdirecting to the first suspected diagnosis of a vallecular cyst. The case highlights the useful contribution of the MRI imaging for differential diagnoses and the need for criteria to indicate further investigations.

Diagnostic Difficulties of Plunging Ranula: A Review of 18 Cases

OBJECTIVE(S)

Despite advancements in imaging techniques and cytological analysis, plunging ranula remains a challenging surgical, radiologic, and pathologic phenomenon. Of the 18 patients we evaluated at our institution, we highlight three cases that illustrate the high rate of misleading imaging and cytological results when assessing plunging ranula.

METHODS

Imaging results, biopsy findings, operative techniques, and pathological reports were reviewed from patients who had either a preoperative or postoperative diagnosis of ranula and underwent surgery by a single head and neck surgeon at a tertiary care center.

RESULTS

Of the 18 identified patients, computed tomography was correct on preoperative imaging 73% of the time and magnetic resonance imaging was correct on preoperative imaging 71% of the time. Two patients underwent preoperative ultrasound and their ultrasound reports did not accurately diagnose the presence of a ranula. Two patients underwent preoperative fine needle aspiration biopsy due to inconclusive preoperative imaging, in which results suggested either a ranula or epidermal cyst. Both ultimately did not match the final pathology. Three of eighteen patients (17%) underwent an inappropriate initial surgery due to incorrect imaging diagnoses and/or biopsy findings.

CONCLUSION

Despite use of preoperative modalities to distinguish plunging ranula from other cystic floor of mouth lesions, surgeons must be aware that no workup modality is fully precise. The potential for revision surgery must be included in all preoperative discussions for presumed plunging ranula.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:2689-2696, 2024.

Malignant and Nonmalignant Lesions of the Oral Cavity

There is a broad spectrum of pathology that occurs in the oral cavity. Knowledge of the different anatomic subsites and contents of each is important for accurate diagnosis and treatment. Oral cavity tumors are predominantly malignant in nature, but there are many nonmalignant lesions of which the practicing clinician should be aware. This article will discuss the anatomy, imaging approaches, and imaging characteristics of nonmalignant and malignant pathology in the oral cavity.

Amylase as a Diagnostic Tool for Plunging Ranula: Clinical Series and Description of the Technique

OBJECTIVES

This study describes a technique of measurement for neck cyst amylase content and reviews the experience of a tertiary referral center for cases of suspected plunging ranula.

METHODS

A retrospective study was performed at the Manukau Surgical Center in Auckland, New Zealand. Patients with a possible diagnosis of plunging ranula based on clinical presentation and diagnostic aspiration of the cyst contents were included. Demographic data, imaging and laboratory findings were collected, along with findings from surgery and histology. The technique for measuring the amylase of the aspirated cyst contents was also carefully recorded.

RESULTS

The 37 cases of confirmed plunging ranula included in this study had a submandibular cystic swelling that was aspirated. Imaging features consistent with a plunging ranula were seen in 89% of the study group. All cases had detectable levels of amylase of ≥3 U/L in the ranula contents. There was large variability (range: 5-560 U/L) in the concentration of amylase, with 70% of the cases demonstrating an amylase concentration below 200 U/L. Aspirates were typically described as viscous (87.5%) and yellow or straw-colored.

CONCLUSION

The combination of clinical presentation, imaging and the presence of amylase in the cyst contents is diagnostic for plunging ranula.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:535-538, 2023.

Salivary gland tumours: an epidemiological review of non-neoplastic and neoplastic pathology

Salivary gland tumours (SGT) demonstrate geographical variation. The primary objective of this study was to determine the types, frequency, distribution, and demographics of non-neoplastic and neoplastic salivary gland pathology at Waikato Hospital, New Zealand (NZ) over a 10-year period. Following this we conducted a 10-year retrospective review of SGT epidemiology from international literature. In total 825 patients were identified, 31% (256/825) with non-neoplastic salivary gland pathology, 34% (284/825) with benign neoplastic pathology, 14% (118/825) with primary malignant lesions, 18% (146/825) with metastatic SGTs, and 3% (21/825) with lymphoma. Patients had a mean (range) age of 58 (3-102) years, were predominantly male (58%, 476/825), and NZ European (65%, 536/825). Tumours were most prevalent in the parotid gland (85%, 484/569), of which 44% (211/484) were malignant. Pleomorphic adenoma was the most common benign (71%, 203/284) and overall (36%, 203/569) tumour, while mucoepidermoid carcinoma (25%, 29/118) and squamous cell carcinoma (SCC) (73%, 106/146) were the most common primary malignant and metastatic SGTs, respectively. Our literature review identified 18 studies consisting of 33,933 patients, of whom 71% (24,013/33,933) had benign SGTs. Pleomorphic adenoma (68%, 16404/24013) and mucoepidermoid carcinoma (29%, 2826/9621) were the most common benign and malignant SGTs, respectively. Low numbers of non-neoplastic and metastatic SGTs were reported in the literature. This research provides a greater understanding of differences in their global distribution. Consistent with previous literature, pleomorphic adenoma and mucoepidermoid carcinoma were the most common benign and malignant SGTs. In NZ, we found high rates of malignant SCC to the parotid gland, consistent with the epidemiology of non-melanoma skin cancer in the country.

Ultrasound in the diagnosis and differential diagnosis of enoral and plunging ranula: a detailed and comparative analysis

Purpose

To develop sonographic criteria for ranula that to allow rapid and precise diagnosis, differentiation between enoral (ER) and plunging ranula (PR), and differential diagnosis from other competing pathologies in this region.

Methods

Patients who presented with or were referred with ranula between 2002 and 2022 were assessed in a retrospective study. After clinical investigation, ultrasound examinations were performed in all cases. Several sonographic parameters describing the echotexture, shape and size of ranulas, their relationship to important surrounding anatomical landmarks and the characteristic spreading pattern of ERs and PRs were elaborated and evaluated.

Results

207 ranulas were included (82.12% ERs and 17.87% PRs). The ranulas were all in close anatomical relationship to the sublingual gland (SLG) and mylohyoid muscle (MM). The echo texture was hypoechoic to anechoic in 97.6% of the lesions. In comparison with ERs, PRs were larger and irregular in shape significantly more often (P = 0.0001). There were significant differences between ERs and PRs in their exact location relative to the SLG (superficial, deep, anterior, each P = 0.0001; posterior, P = 0.03) and level of the MM (above, below, above and below, P = 0.0001 each). The exact extent and plunging pattern were depicted in all PRs, but naturally in none of the ERs.

Conclusions

The ultrasound criteria developed in this study, confirming previously published results, indicate that ultrasound is an excellent diagnostic tool for diagnosing ranula and differentiating between ERs and PRs.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: The Neck and Lymph Nodes, Metastasis, and Melanocytic Tumors

The changes made in the fifth edition of the WHO Classification of Head and Neck Tumors demonstrate the recent diagnostic, histopathological, and molecular advances in the field, and this updated information will hopefully lead to improved and standardized tumor subtyping. This review summarizes the changes related tumors and tumor-like lesions of the neck and lymph nodes (Chapter 11), metastasis to the head and neck region (Chapter 15), and melanocytic tumors (Chapter 10).

Bilateral Plunging Ranulas in South Auckland: Evidence for a Genetic Basis

OBJECTIVES

We present a series of bilateral plunging ranula patients to examine the etiology, diagnosis, treatment, and prognosis of this condition.

METHODS

A retrospective chart review was performed on all cases of plunging ranula treated at the Department of Otolaryngology-Head and Neck Surgery, Counties Manukau District Health Board, New Zealand, between 2001 and 2019.

RESULTS

There were 17 patients with bilateral plunging ranulas from a total of 187 plunging ranula patients. Eight patients were of Pacific Island descent; six were Maori; and three were Asian. There were no European patients with bilateral plunging ranulas. There were three types of bilateral plunging ranula patients: 1) Metachronous plunging ranulas-Five patients presented with a unilateral plunging ranula with no evidence of a contralateral plunging ranula on initial imaging. Despite negative contralateral imaging findings, these patients developed a clinically evident contralateral plunging ranula 21 to 61 months later. 2) Synchronous plunging ranulas detected on imaging-Eight patients presented with a clinically evident unilateral plunging ranula but also had a contralateral plunging ranula detected on imaging. 3) Clinically evident synchronous plunging ranulas-Four patients presented with bilateral clinically evident plunging ranulas, which were also evident on imaging. Twelve patients underwent bilateral transoral sublingual gland excision and plunging ranula evacuation.

CONCLUSION

All patients with a unilateral plunging ranula should be advised of the potential for developing contralateral disease, and this should be emphasized in patients of Pacific Island, Maori, and Asian descent.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:73-77, 2021.