A Case Report on Thornwaldt Cyst: An Uncommon Nasopharyngeal Anomaly in an 18‐Year‐Old Male

ABSTRACT

Thornwaldt cysts are rare, benign nasopharyngeal remnants that often remain asymptomatic but can cause significant discomfort when symptomatic. This case report discusses an 18‐year‐old male who experienced a persistent foreign body sensation in his nose for 4 months. Initial investigations, including MRI, revealed a Thornwaldt cyst occupying 70% of the nasopharyngeal space. Diagnostic confirmation was obtained through nasal endoscopy and histopathological examination. The patient underwent successful endoscopic surgical excision of the cyst, resulting in complete symptom resolution. At a one‐year follow‐up, the patient remained symptom‐free with no signs of recurrence. This case underscores the importance of recognizing Thornwaldt cysts in patients with nonspecific symptoms and highlights the efficacy of endoscopic surgical intervention for both symptom relief and prevention of recurrence. Accurate diagnosis using advanced imaging techniques and histopathological confirmation is crucial for appropriate management and favorable patient outcomes.

Summary.

• Even unusual diagnoses such as Thornwaldt cyst must be considered for chronic unexplained nasopharyngeal symptoms.

• MRI is used to provide a proper diagnosis; endoscopic excision can be used to fulfill the medical requirement of providing safe, minimally invasive intervention with full resolution of the symptoms and less possible recurrence.

1. Introduction

Thornwaldt cyst, a rare and benign condition stemming from a nasopharynx cystic remnant, typically manifests without symptoms, yet it may gradually present specific nasal, otological, cervical, or oral indications [1, 2, 3]. Due to its often asymptomatic nature, this condition can persist undetected for an extended duration, evading diagnosis [1]. When the cyst remains asymptomatic, a treatment course might not be necessary, allowing for observation. However, in cases where symptoms develop or the cyst becomes problematic, an endoscopic surgical procedure stands out as a beneficial treatment, addressing the condition effectively [4]. Here, we present a case of an 18‐year‐old male with complaints of foreign body sensation that later on revealed to be a Thornwaldt cyst.

2. Case History

18 years old male presented with complaints of foreign body sensation in the nose for 4 months. According to the patient, he was apparently well 4 months back when he developed a foreign body sensation in the nose, which was insidious in onset, intermittent, and had no any aggravating or relieving factors associated with the discomfort.

No history of nasal obstruction, nasal discharge, nasal bleeding, any mass coming out of the nose, fever, voice change, anosmia, hyposmia, pain, headache, difficulty in breathing, difficulty in swallowing.

3. Methods

The investigation report revealed a total white blood cell count of 4700/mm³, neutrophil 65%, lymphocyte 27%, eosinophil 3%, monocyte 4%, hemoglobin 14.6 g%. Anterior rhinoscopy showed no mass or crust in the bilateral nasal cavity. Bilateral nasal walls appear normal with no turbinate hypertrophy. The inferior and middle meatus appeared normal. The floor and roof appeared normal. The nasal mucosa appeared normal in the bilateral nasal cavity.

On posterior rhinoscopy, a pinkish round smooth‐surfaced cystic mass was present extending into the nasopharynx, occupying approximately half of the cavity.

Examination of the ears and oral cavity yielded normal findings.

Magnetic Resonance Imaging (MRI) was planned, which showed a small T2 hyperintense signal and T1 isointense signal lobulated mass measuring 3.2 × 2.7 cm noted in the midline of the nasopharynx, considering a small Thornwaldt cyst in the midline of the nasopharynx. An MRI image is shown in Figure 1. Diagnostic nasal endoscopy with a 0° fiberoptic Karl Storz endoscope was performed, revealing significant blockage of the nasopharynx by the cystic swelling, prompting multiple biopsies from different sites within the nasopharynx. These samples were sent for histopathological examination (HPE) to ascertain the nature of the cyst and its implications. Endoscopic imaging view is shown in Figure 2. As a result, a complete surgical excision of the cyst was performed endoscopically.

FIGURE 1.

MRI scans (sagittal section) of the nasopharynx showing the nasopharyngeal cyst in the midline of the nasopharynx.

FIGURE 2.

Nasopharyngeal endoscopic view showing a smooth cystic mass arising from the roof of the nasopharynx.

4. Outcome and Follow‐Up

Following the biopsy, the histopathologic examination confirmed the nature of the cystic mass, indicating cylindrical ciliated epithelium with inflammatory cells, granulated tissues, and proliferation of mucus glands on the cyst wall, thereby suggesting Thornwaldt Cyst. There was no evidence of malignancy found within the sample.

Fortunately, the procedure was successful, removing the entirety of the cyst. At the one‐year follow‐up, the patient remained free from symptoms related to the previous foreign body sensation, and there were no signs of recurrence, indicating a positive outcome from the surgery.

5. Discussion

Tornwaldt cyst, also known as Thornwaldt cyst or nasopharyngeal cyst, is the remnant of the notochord, forming a midline bursa in the nasopharynx situated above the upper border of the superior constrictor muscle. The interaction between these remnants and pharyngeal ectoderm creates conditions for the ingrowth of respiratory epithelium, leading to the formation of Tornwaldt's bursa, which drains into the nasopharyngeal cavity [4, 5]. The cyst typically develops congenitally, with its embryological origin occurring between days 16 and 22 of development [3]. It emerges in the pharyngeal bursa region due to communication between the notochord and nasopharyngeal endoderm [2]. The cyst evolves when the orifice is obstructed either partially or completely [5].

There is an ongoing debate regarding the cyst's etiology, commonly described as a notochord remnant, but alternative views suggest iatrogenic occlusion following adenoidectomy or chronic inflammation [5]. Development occurs when the potential space of the epithelial lining secretes mucus following obstruction or recurrent infection [6]. Although Thornwaldt cysts are usually asymptomatic, symptomatic presentations may include nasal obstruction, foreign body sensation, hearing loss, halitosis, and nasopharyngeal discharge [7]. Infection can lead to abscess formation, with associated symptoms such as dull occipital headache worsened by head movement, postnasal discharge, halitosis, sore throat, or neck stiffness [8].

Diagnostic modalities for Thornwaldt cyst include radiological findings, with Computed Tomography (CT) scan or MRI being commonly used. On CT scan, the cyst appears as a midline mass in the nasopharynx, situated high between the longus capitis muscles, containing fluid resembling cerebrospinal fluid, and not enhancing even after contrast [8]. MRI is considered the preferred investigation, as high‐intensity T1 and T2 weighted images indicate the presence of proteins or hemorrhages within the cyst [9]. The reported incidence of Thornwaldt cyst in routine brain and cervical MRI scans is approximately 0.2%–0.5%, while postmortem autopsies report an incidence of about 5% [1, 10].

In a study by Moody et al., it was noted that the size of the cyst on MRI tends to be smaller than on CT scan [11]. Differential diagnoses for Thornwaldt cyst include branchial cleft cyst, Rathke's cyst, adenoid retention cyst, meningocele, encephalocele, and meningomyelocele [9].

The lesion was present in the midline and posterior roof of the nasopharynx. Whereas branchial cleft cysts are usually found in the lateral site of the nasopharyngeal space [12]. Rathke's cysts are located in the craniopharyngeal canal, between the anterior and posterior pituitary glands. Moreover, histopathologic examination showed cylindrical ciliated epithelium which is consistent with Thornwaldt's cyst. While Rathke's cyst has an internal stratified squamous lined epithelium [13]. Adenoid retention cyst has abundant lymphoid tissue, germinal centers, and many inflammatory cells [14]. Meningocele and encephalocele occur along the spine (often in the lower back or neck) and head (occipital region) or between the eyes (frontoethmoidal region) respectively. Moreover, the patient did not have symptoms that are commonly seen in meningocele and encephalocele like weakness in limbs, paraplegia, hemiplegia, seizure, bowel/bladder dysfunction, and developmental delays [15]. MRI did not show any irregular borders, bone erosion, or intracranial extension. Clinically, no neck masses and lymph nodes were palpable. There was also no evidence of squamous cell or malignant cells found in HPE. Therefore, nasopharyngeal carcinoma was ruled out [16].

The definitive surgical interventions for Thornwaldt cyst involve excision or marsupialization, aided by nasal endoscopes and microdebriders [9]. For smaller cysts, transnasal endoscopic access is recommended, while larger cysts may require retropalatal access using a 70° endoscope. Aspiration alone is discouraged due to the risk of recurrence [4].

The use of endoscopic procedures and computer‐assisted devices has significantly improved surgical clarity and ease, leading to reduced surgical durations [4]. The unavailability of GRASE (Gradient and Spin Echo) T2 MRI could be considered a limitation of the study. GRASE T2 MRI sequences provide enhanced imaging capabilities by combining the advantages of both gradient echo and spin echo sequences, allowing for better visualization of fluid‐filled structures like Thornwaldt cysts [17].

Author Contributions

Dhiraj Chaurasia: conceptualization, data curation, writing – original draft, writing – review and editing. Abdus Samad Ansari: conceptualization, investigation, methodology, writing – original draft, writing – review and editing. Rishita Dallakoti: data curation, investigation, methodology, writing – review and editing. Season Shrestha: conceptualization, supervision, writing – original draft, writing – review and editing. Inku Shrestha Basnet: conceptualization, formal analysis, supervision, validation.

Consent

Written informed consent was obtained from the patient before the study for the publication of this Case Report.

Conflicts of Interest

The authors declare no conflicts of interest.

Chaurasia D., Ansari A. S., Dallakoti R., Shrestha S., and Basnet I. S., “A Case Report on Thornwaldt Cyst: An Uncommon Nasopharyngeal Anomaly in an 18‐Year‐Old Male,” Clinical Case Reports 13, no. 9 (2025): e70936, 10.1002/ccr3.70936.

Data Availability Statement

The authors have nothing to report.