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Abstract

Objective

To compare the clinical diagnostic value of ultrasonography (USG), computed tomography (CT), and magnetic resonance imaging (MRI) for nasolabial cysts.

Methods

The clinical and imaging data of 20 patients with 21 nasolabial cysts confirmed surgically and histopathologically were retrospectively analyzed.

Results

The largest cyst was 3.4 × 2.7 × 2.3 cm, and the smallest cyst was 1.1 × 0.7 × 0.5 cm. All cysts were located in the soft tissue between the nasolabial fold and maxillary bone. USG showed sensitivity of 95%, accuracy of 95%, and a missed diagnosis rate of 5%; CT showed sensitivity of 80%, accuracy of 80%, and a missed diagnosis rate of 20%; and MRI showed sensitivity of 85%, accuracy of 85%, and a missed diagnosis rate of 15%.

Conclusions

USG showed higher sensitivity and accuracy and a lower missed diagnosis rate than CT and MRI. Therefore, USG is worth popularizing on a large scale for the diagnosis of nasolabial cysts.

Keywords

Nasolabial cyst diagnosis ultrasonography computed tomography magnetic resonance imaging sensitivity accuracy

Introduction

A nasolabial cyst is a relatively rare non-odontogenic cyst, and the 2017 World Health Organization classification no longer includes it among jaw cysts. It was first reported by Emil Zuckerkandl in 1882.¹ Nasolabial cysts are usually located in the soft tissue between the nasolabial fold and maxillary bone. They have been known by many names, such as nasal vestibular cyst, nasoalveolar cyst, nasal mucoid cyst, nasal wing cyst, and nasoglobular cyst.² The estimated annual incidence of nasolabial cysts among the general population is about 1.6 per 100,000 people, and these cysts are clinically more common in women with a male:female ratio of about 1.0:3.6.^3,4 The age predilection of nasolabial cysts is 40 to 50 years. Most cases are unilateral; the incidence rate of bilateral cysts is about 10%.⁵

Nasolabial cysts usually grow slowly, and there are often no obvious symptoms or physical signs in the early stage. With the gradual enlargement of a nasolabial cyst, a soft quasi-circular bulge appears at the bottom of the nasal cavity accompanied by a sense of fluctuation and generally no tenderness.⁶ The most typical symptom is local swelling; nasal obstruction or headache may appear in some patients. If combined with infection, cysts may rapidly enlarge with an aggravated sense of pain and swelling.⁷

To diagnose a nasolabial cyst, it is necessary to comprehensively consider the patient’s symptoms, physical signs, and imaging examination findings. Computed tomography (CT) and magnetic resonance imaging (MRI) can show the location, shape, and adjacent anatomical structures of a nasolabial cyst, which is helpful for the diagnosis or differential diagnosis.^8,9 Compared with CT and MRI, ultrasonography (USG) can more clearly reveal the cystic wall and cystic contents; therefore, USG findings facilitate more accurate judgment of the nature of the lesion.¹⁰ The purpose of this study was to further explore the clinical diagnostic value of USG by comparing these three imaging modalities and to provide a new way for otorhinolaryngologists to diagnose nasolabial cysts.

Materials and methods

General information

Twenty patients with 21 nasolabial cysts confirmed surgically and histopathologically in Shandong Provincial ENT Hospital from October 2021 to March 2022 were retrospectively analyzed. All patients were examined by the same three imaging modalities within 1 week before the operation. The equations for calculating the diagnostic performance parameters were as follows: sensitivity = true positive/(true positive +false negative) × 100%; accuracy = (true positive + true negative)/(true positive +false positive + true negative + false negative) × 100%; and missed diagnosis rate =false positive/(true positive + false negative) × 100%. All patient details were de-identified. The reporting of this study conforms to the CARE Guidelines.¹¹

Ethical approval

We briefed all participants in detail on the process of sample collection, and all participants provided written informed consent. The study was performed in accordance with the Declaration of Helsinki. All procedures in this study related to human participants were performed following the ethical standards of the institutional and/or national research committees’ ethical standards. This study was approved by the Ethics Review Committee of Shandong Provincial ENT Hospital (China approval number: XYK-20210703).

USG

A LOGIQ E11 ultrasound scanner equipped with a 15-MHz high-frequency ultrasound probe (GE Healthcare, Chicago, IL, USA) was used to perform the ultrasonic scanning. We placed the probe at the nasolabial fold and scanned the area between the skin and maxillary bone. The obtained ultrasonic images were independently analyzed by two sonologists with senior professional titles. When their diagnoses conflicted, a consensus-based diagnosis was made. The two sonologists were blinded to the clinical information and other auxiliary examination results in advance. The echo intensity was subjectively graded in comparison to adjacent normal muscle tissue: hyperechoic (brighter than muscle), medium echo (equivalent to muscle), hypoechoic (darker than muscle), anechoic (no internal echo), and mixed echo (≥2 kinds of echo).

CT

Targeted scanning was performed with a Discovery 750 multi-layer spiral CT scanner (GE Healthcare). The scanning range ranged from the hard palate to the skull base. Scans were performed only in the axial direction. The coronal and sagittal images were reformations based on the axial source data. The contrast agent iomeprol (50 mL) was intravenously injected during enhanced scanning at a rate of 3.5 mL/s. The obtained CT images were independently analyzed by two CT radiologists with senior professional titles. When their diagnoses conflicted, a consensus-based diagnosis was made. The two CT radiologists were blinded to the clinical information and other auxiliary examination results in advance. The density was judged as low, medium, high, or mixed density (≥2 kinds of density) according to the normal muscle tissue (medium density) adjacent to the cysts.

MRI

The patients were examined with a MAGNETOM Prisma 3.0T superconducting MRI scanner (Siemens, Erlangen, Germany). In the plain scan, T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) were performed in the axial plane, whereas T2WI was performed only in the coronal and sagittal planes. The contrast agent gadoteridol (0.2 mL/kg) was intravenously injected during enhanced scanning at a rate of 2.5 mL/s. T1WI was performed with the turbo spin echo sequence, and the imaging parameters were as follows: repetition time (TR), 607 ms; echo time (TE), 10 ms; averages, 2; slice thickness, 3 mm; slice gap, 0.4 mm, and matrix, 256 × 256. T2WI was also performed with the turbo spin echo sequence, and the imaging parameters were as follows: TR, 6620 ms; TE, 80 ms; averages, 2; slice thickness, 3 mm; slice gap, 0.4 mm; and matrix, 384 × 384. Diffusion-weighted imaging (DWI) was performed with the RESOLVE sequence, and the imaging parameters were as follows: TR, 3260 ms; TE, 57 ms; slice thickness, 3 mm; slice gap, 0.4 mm; matrix, 192 × 192; and b = 1000 s/mm². After scanning, the images were independently analyzed by two MRI radiologists with senior professional titles. When their diagnoses conflicted, a consensus-based diagnosis was made. The two MRI radiologists were blinded to the clinical information and other auxiliary examination results in advance. The signal intensity was judged as hypointense, isointense, hyperintense, or mixed (≥2 kinds of intensity) according to the normal muscle tissue (isointense) adjacent to the cysts.

Statistical analysis

The experimental data were analyzed using SPSS 26.0 statistical software (IBM Corp., Armonk, NY, USA). The sensitivity, accuracy, specificity, missed diagnosis rate, and misdiagnosis rate were calculated by Pearson’s chi-square test. A P value of ≤0.05 was considered statistically significant for all analyses.

Results

Clinical characteristics

In total, 21 cysts in 20 patients were found by the imaging examinations. The largest cyst was 3.4 × 2.7 × 2.3 cm, and the smallest cyst was 1.1 × 0.7 × 0.5 cm. All cysts were located in the soft tissue between the nasolabial fold and maxillary bone. The most common symptom was swelling (19/20 patients, 95%). Other concomitant symptoms included pain (11/20 patients, 55%), nasal obstruction (6/20 patients, 30%), headache (1/20 patients, 5%), and hyposmia (1/20 patients, 5%). The detailed clinical characteristics are shown in Supplementary Table S1.

Diagnostic performance parameters

To compare the diagnostic value of USG, CT, and MRI, we calculated the diagnostic performance parameters for each modality (Table 1). Using USG, 19 patients were true-positive, 0 were false-positive, 0 were true-negative, and 1 was false-negative (sensitivity, 95%; accuracy, 95%; and missed diagnosis rate, 5%). Using CT, 16 patients were true-positive, 0 were false-positive, 0 were true-negative, and 4 were false-negative (sensitivity, 80%; accuracy, 80%; and missed diagnosis rate, 20%). Using MRI, 17 patients were true-positive, 0 were false-positive, 0 were true-negative, and 3 were false-negative (sensitivity, 85%; accuracy, 85%; and missed diagnosis rate, 15%).

Table 1.

Diagnostic performance parameters of USG, CT, and MRI.

Examinations		Histopathological results		Sensitivity	Accuracy	Specificity	Missed diagnosis rate	Misdiagnosis rate
Examinations		+ (n = 20)	− (n = 0)	Sensitivity	Accuracy	Specificity	Missed diagnosis rate	Misdiagnosis rate
USG	+	19	0	95%	95%	–	5%	–
USG	−	1	0	95%	95%	–	5%	–
CT	+	16	0	80%	80%	–	20%	–
CT	−	4	0	80%	80%	–	20%	–
MRI	+	17	0	85%	85%	–	15%	–
MRI	–	3	0	85%	85%	–	15%	–

n refers to number of patients.

USG, ultrasonography; CT, computed tomography; MRI, magnetic resonance imaging.

USG manifestations

A total of 71% of cysts were regular, showing a quasi-circular shape, whereas 29% were irregular. A total of 76% of cysts were well-defined, whereas the boundaries of 24% were unclear. A total of 52% of cysts were anechoic (Figure 1(a)), 43% showed mixed echo, and 5% were hypoechoic. Hyperechoic areas were sometimes detected inside the cysts, and the reason may have been the formation of local precipitation composed of red blood cells, proteins, or cholesterol crystals. The echo distribution of 43% of cysts was heterogeneous and that of 5% of cysts was homogeneous. The internal acoustic transmission of 52% of cysts was good and that of 48% of cysts was poor. The bones around 86% of cysts were compressed, whereas no obvious bone compression was found around 14% of cysts. Changes of adjacent bones with arc- or fan-shaped indentation was seen in typical cases (Figure 1(b)). Stratification was found in 14% of cysts (Figure 1(c)), and intracapsular deposits were observed in 24% of cysts (Figure 1(d)). No significant blood flow signals were detected around 76% of cysts, whereas such signals were found around 24% of cysts (Figure 1(e)). The inner wall of 62% of cysts was smooth, whereas that of 38% of cysts was non-smooth. Additionally, we observed obvious thickening of the cystic wall (≥0.3 cm) in 29% of cysts (Figure 1(f)). The USG imaging characteristics are presented in Supplementary Table S2.

Figure 1.

Ultrasonography images with Doppler blood flow signals in patients with nasolabial cysts. (a) The cyst was located in the soft tissue between the nasolabial fold (black arrow) and maxillary bone (white arrow). The cyst showed an anechoic and well-defined area (white triangle). (b) The maxillary bone showed an arc-shaped indentation (white arrow). (c) The cyst showed stratification (white arrow). (d) The cyst showed intracapsular deposits (white arrow). (e) The cyst showed blood flow signals (white arrow) and (f) The cystic wall was obviously thickened (white arrow).

CT manifestations

Fifteen cysts were regular, showing a quasi-circular shape, whereas six cysts were irregular. Sixteen cysts were well-defined, and the boundaries of five were unclear. Twelve cysts showed low density (Figure 2(a)), eight showed high density (Figure 2(b)), and one showed medium density. The density distribution of 13 cysts was homogeneous, whereas that of 8 cysts was heterogeneous. The CT value of the cysts ranged from 12 Hounsfield units (HU) to 86 HU with a mean of 38.2 HU. Contrast-enhanced scans were performed in three patients, and no obvious enhancement was found on the CT images (Figure 2(c)). The bones around 18 cysts were compressed, whereas no obvious bone compression was observed around 3 cysts. Arc-shaped or fan-shaped changes of compressed bones were seen on CT images (Figure 2(d)–(f)). The CT imaging characteristics of are shown in Supplementary Table S3.

Figure 2.

Axial, coronal, and sagittal computed tomography (CT) images in patients with nasolabial cysts. (a) A quasi-circular and low-density cyst was located in the right nasolabial fold (white arrow). (b) A well-defined and high-density cyst was located in the left nasolabial fold (white arrow). (c) An enhanced scan of the cyst showed no obvious signs of enhancement (white arrow). (d) An axial CT image showed a fan-shaped indentation (white arrow) on the maxillary bone. (e) A coronal CT image showed an arc-shaped indentation on the alveolar bone (white arrow) and (f) A sagittal CT image showed an arc-shaped indentation on the maxillary bone (white arrow).

MRI manifestations

Fifteen cysts were regular, showing a quasi-circular shape, whereas six cysts were irregular. Sixteen cysts were well-defined, whereas the boundaries of five cysts were unclear. Eleven cysts showed hypointensity on T1WI (Figure 3(a)), nine cysts showed hyperintensity (Figure 3(c)), and one cyst showed isointensity. Thirteen cysts were homogeneous on T1WI, and eight cysts were heterogeneous. Twenty cysts showed hyperintensity on T2WI (Figure 3(b) and (d)), and one cyst showed isointensity. Thirteen cysts were homogeneous on T2WI, whereas eight cysts were heterogeneous. Contrast-enhanced scans were processed in three patients, and there were no obvious enhanced signs on MRI. The bones around 18 cysts were compressed, and no obvious bone compression was found around 3 cysts. Arc-shaped or fan-shaped indentation was also observed on MRI (Figure 4(a) and (b)). Thirteen cysts showed hyperintensity on DWI, and eight cysts showed hypointensity. Fifteen cysts showed hyperintensity on apparent diffusion coefficient images, and six cysts showed hypointensity. Six cysts showed diffusion restriction (i.e., hyperintensity) on DWI and hypointensity on apparent diffusion coefficient images (Figure 4(c) and (d)). The MRI characteristics are described in Supplementary Table S4.

Figure 3.

Axial magnetic resonance images in patients with nasolabial cysts. (a) The cyst showed homogeneous hypointensity on T1-weighted imaging (T1WI) (white arrow). (b) The cyst showed homogeneous hyperintensity on T2-weighted imaging (T2WI) (white arrow). (c) The cyst showed homogeneous hyperintensity on T1WI (white arrow) and (d) The cyst compressed the left inferior turbinate on T2WI (white arrow).

Figure 4.

Coronal and sagittal magnetic resonance images: diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) images in patients with nasolabial cysts. (a) Coronal T2-weighted imaging (T2WI) showed an arc-shaped indentation on the alveolar bone (white arrow). (b) Sagittal T2WI showed an arc-shaped indentation on the maxillary bone (white arrow). (c) On DWI with limited diffusion, the cyst showed hyperintensity (white arrow) and (d) On ADC images with limited diffusion, the cyst showed hypointensity (white arrow).

Discussion

A nasolabial cyst is a rare disease in otorhinolaryngology and is associated with no obvious specific symptoms or clinical signs. The pathogenesis and pathophysiology of nasolabial cysts remain unclear. In 1898, Brown-Kelly¹² proposed that obstruction of the glandular orifice of the mucous glands in the nasal floor mucosa leads to the retention of glandular secretions. In 1913, Klestadt¹³ proposed that during the period of embryonic development, nasolabial cysts originate from the vagal epithelium at the junction of the maxillary process, medial nasal process, and lateral nasal process. In 1920, Bruggemann¹⁴ proposed that nasolabial cysts originate from the residual epithelium of the nasolacrimal duct. In addition, trauma or infection stimulate the development of dormant epithelial tissue into the cystic structure, which might be similar to the pathogenesis of a branchial cleft cyst.

Radiography, USG, CT, and MRI are commonly used in the clinical diagnosis of nasolabial cysts. According to Amaral et al.,¹⁵ the radiological technique combining two X-ray contrast agents with different imaging angles can be used for the diagnosis and treatment of nasolabial cysts. However, nasolabial cysts are soft tissue lesions and the bony structures of the maxillofacial region are complex, which results in more overlapping on X-ray images. Therefore, X-ray is rarely used in the diagnosis of nasolabial cysts. USG is a common examination method for maxillofacial diseases and clearly shows cervical lymph node metastasis, the internal vascular structure of the tumor, and salivary gland-related lesions. A nasolabial cyst is a soft tissue lesion with a superficial anatomical position, and there are no bony structures on the surface of the cyst that interfere with the transmission of ultrasonic signals, highlighting the feasibility of USG.

By analyzing the ultrasonographic images of the patients, we summarized the three typical ultrasonographic findings of nasolabial cysts as follows. First, a nasolabial cyst is a quasi-circular anechoic cystic mass with good internal acoustic transmission. Second, the cyst has a clear boundary and smooth inner wall, and there are generally no obvious blood flow signals inside or around the cyst. Third, when the cyst is larger or the disease course is longer, there may be changes in the adjacent bone, and the surrounding bone is typically compressed in an arc or fan shape. Similarly, we summarized the four main ultrasonographic findings of nasolabial cysts complicated with infection as follows. First, the shape of the cyst is irregular, the boundary is blurred, and the inner wall is non-smooth. Second, the cyst is characterized by mixed echo intensity, heterogeneous echo distribution, and poor internal acoustic transmission. Third, a blood flow signal can be detected around the cyst, but there is generally no obvious blood flow signal inside the cyst. Fourth, the wall of the cyst sometimes thickens, and stratification phenomena or intracapsular deposits can be seen inside the cyst. According to a study by Liu et al.,¹⁶ CT did not reveal small nasolabial cysts and nasal alar tumors; therefore, USG was the first choice for patients with nasolabial cysts. In addition, USG does not cause radiation damage to the human body, and the cyst can be dynamically observed from multiple sections and angles.¹⁷ Notably, some patients have metal implants such as dentures, stents, birth control devices, fixed nails, and titanium alloy plates. CT and MRI for such patients produce metal artifacts, which seriously interferes with the clinician’s judgment of the diagnosis. Therefore, compared with CT and MRI, USG has more extensive applicability for the diagnosis of nasolabial cysts.

Generally speaking, axial scanning is the best way to detect and display nasolabial cysts. However, coronal and sagittal scanning can be used to observe the extent of bone compression caused by the cyst and to better show the normal and variant anatomical structures of the nasal cavity and paranasal sinuses.¹⁸ Therefore, coronal and sagittal scanning can be used to supplement and improve axial scanning. The reason for the increased density of nasolabial cysts may be the large amounts of proteins or cholesterol crystals within the cysts.¹⁹ In a study by Chindasombatjaroen et al.,²⁰ CT showed subtle bone changes and MRI could better show the boundary and cystic contents, while the number of cysts detected by MRI was higher than that by CT. The density of a nasolabial cyst is basically close to that of soft tissue; thus, CT cannot clearly distinguish the cystic wall from the cystic contents. Therefore, it is difficult to differentiate a nasolabial cyst from other benign soft tissue tumors on CT images. Furthermore, although relevant protective measures are taken in the process of CT examination, it is inevitable that patients will still receive a certain dose of radiation.

Because the soft tissue contrast resolution of MRI is higher, MRI can facilitate better judgment of the boundary of the cyst and the nature of the cystic contents than can CT.²¹ The increased signal intensity on T1WI may be caused by red blood cells, proteins, cholesterol crystals, mucus, or pus within the cysts.²² The cysts can be observed along multiple planes and directions on MRI, and stereoscopic anatomical images provide a reliable diagnostic basis for clinicians.²³ MRI does not involve ionizing radiation. However, MRI is time-consuming and expensive, limiting its large-scale clinical promotion in the diagnosis of nasolabial cysts.

The diseases that must be differentiated from nasolabial cysts mainly include odontogenic cysts and facial cleft cysts.²⁴ Histopathologic examinations are necessary to definitively distinguish between nasolabial cysts and odontogenic cysts or facial cleft cysts. In addition, nasolabial cysts must be differentiated from structures located in the nasal vestibular region, including hemangiomas, lymph nodes, and other tumor lesions. On USG, hemangiomas exhibit internal vascularity and solid components, whereas lymph nodes are solid lesions with a linear hilum.

Among the patients included in this study, there was a very interesting case of a 49-year-old woman with bilateral nasolabial cysts. Her chief complaint was repeated swelling and pain in the left nasolabial fold and only swelling in the right nasolabial fold. Physical examination showed that the cyst on the left was hard while the right was soft. Based on the patient’s symptoms and physical signs, the preliminary diagnosis was repeated infection of the left cyst but not the right. A series of subsequent imaging examinations confirmed our initial diagnosis. USG showed mixed echo, a stratification phenomenon, and intracapsular deposits in the left cyst and an anechoic area in the right cyst (Figure 5(a)). Interestingly, both cysts showed low density on CT images with no substantial difference between the two sides (Figure 5(b)). Therefore, USG was able to detect cyst infection whereas CT could not. T1WI and T2WI of the left cyst showed hyperintensity, whereas the right cyst showed a low signal on T1WI and high signal on T2WI (Figure 5(c) and (d)). Finally, the patient underwent bilateral endoscopic uncovering of the nasal cysts and recovered well after the operation (Figure 5(e) and (f)).

Figure 5.

Imaging examinations and intraoperative nasal endoscopic images in a patient with bilateral nasolabial cysts. (a) The left cyst showed stratification and intracapsular deposits (white arrow). The right cyst showed an anechoic area (white triangle). (b) Both cysts showed homogeneous low density (white arrow). (c) On T1-weighted imaging, the left cyst showed hyperintensity (white arrow) and the right cyst showed hypointensity (white arrow). (d) On T2-weighted imaging, both cysts showed hyperintensity (white arrow). (e) Nasal endoscopy showed a smooth semicircular bulge in the right nasal vestibular area (white arrow) and (f) Images taken in the process of endoscopically uncovering the nasal cyst (white arrow).

Conclusions

Traditional diagnostic methods have obvious limitations because of the anatomical location of nasolabial cysts. This study broadens the application of USG and provides a reliable objective basis for the diagnosis, differential diagnosis, and treatment of nasolabial cysts. Compared with CT and MRI, USG has the advantages of higher sensitivity, higher accuracy, a lower missed diagnosis rate, a simple operation, a short examination time, no ionizing radiation, strong repeatability, and relatively low cost. Therefore, USG could be readily popularized on a large scale in grassroots hospitals, and there is broad clinical application value for USG-based diagnosis of nasolabial cysts.

Supplemental Material

sj-pdf-1-imr-10.1177_03000605221147201 - Supplemental material for Comparative analysis of three common imaging modalities for nasolabial cysts

Supplemental material, sj-pdf-1-imr-10.1177_03000605221147201 for Comparative analysis of three common imaging modalities for nasolabial cysts by Shengyang Liu, Dingqian Hao, Liang Yu, Hui Ma, Hui Zhao, Shujuan Sun, Peng Yu, Hongzhi Ji, Li Shi, Yuzhu Wan and Aiping Chen in Journal of International Medical Research

Footnotes

Acknowledgement

The authors are particularly grateful to Wei Zhang at the Shandong Second Provincial General Hospital for providing the imaging data.

Author contributions

All authors made a significant contribution to the work reported, whether in the study conception, design, or execution; data acquisition, analysis, or interpretation; or in all of these areas. All authors took part in drafting, revising, or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the report has been submitted; and agree to be accountable for all aspects of the work.

Data availability statement

All data generated or analyzed during this study are included in this published article and its supplementary information files.

Declaration of conflicting interests

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Funding

The authors disclose receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by a grant from the National Natural Science Foundation of China (No. 8187040823).

ORCID iDs

Shengyang Liu

Dingqian Hao

Shujuan Sun

Supplemental material

Supplemental material for this article is available online.

References

Almutairi

Alaglan

Alenezi

, et al. Nasolabial cyst: case report and review of management options. BMC Surg 2020; 20: 10. 2020/01/12. DOI: 10.1186/s12893-020-0677-3.

Dghoughi

Bilateral nasolabial cyst.

J Stomatol Oral Maxillofac Surg 2017; 118: 385–388. 2017/08/26. DOI: 10.1016/j.jormas.2017.07.007.

Sheikh

Chin

Fang

, et al. Nasolabial cysts: a systematic review of 311 cases. Laryngoscope 2016; 126: 60–66. 2015/07/15. DOI: 10.1002/lary.25433.

Bijou

Laababsi

Mennouni

, et al. An atypical presentation of a bilateral nasolabial cyst: a case report. J Surg Case Rep 2021; 2021: rjab017. 2021/03/19. DOI: 10.1093/jscr/rjab017.

Anekar

Kumar

Chirakara

, et al. Bilateral nasolabial cyst: a rare case. BMJ Case Rep 2018; 2018: bcr2018226049. 2018/09/02. DOI: 10.1136/bcr-2018-226049.

Balaji

Thavarajah

Balaji

Nasolabial cyst in buccal mucosa. Indian J Dent Res 2019; 30: 957–959. 2020/01/16. DOI: 10.4103/ijdr.IJDR_861_19.

Sato

Morita

Kabasawa

, et al. Bilateral nasolabial cysts: a case report. J Med Case Rep 2016; 10: 246. 2016/09/09. DOI: 10.1186/s13256-016-1024-2.

Han

Chang

Lee

, et al. Cystic expansile masses of the maxilla: differential diagnosis with CT and MR. AJNR Am J Neuroradiol 1995; 16: 333–338. 1995/02/01.

Curé

Osguthorpe

Van Tassel

MR of nasolabial cysts.

AJNR Am J Neuroradiol 1996; 17: 585–588. 1996/03/01.

10.

Yeh

Wang

CP.

Transcutaneous ultrasonography for diagnosis of nasolabial cyst.

J Craniofac Surg 2017; 28: e221–e222. 2017/05/05. DOI: 10.1097/scs.0000000000003403.

11.

Gagnier

Kienle

Altman

, et al. The CARE guidelines: consensus-based clinical case reporting guideline development. BMJ Case Rep 2013; 2013: bcr2013201554. 2013/10/25. DOI: 10.1136/bcr-2013-201554.

12.

Brown-Kelly

Cysts of the floor of the entrance of the nose. J Laryngol Otol 1898; 13: 272–276.

13.

Klestadt

WD.

Nasal cysts and the facial cleft cyst theory. Ann Otol Rhinol Laryngol 1953; 62: 84–92. DOI: 10.1177/000348945306200108.

14.

Bruggemann

Nasolabial cyst management. Arch Laryngol Rhinol 1920; 33: 1–5.

15.

Amaral

De Freitas

De Fátima da Conceição

, et al. Nasolabial cyst with radiographic contrast medium: report of two cases. Dentomaxillofac Radiol 2005; 34: 256–258. 2005/06/18. DOI: 10.1259/dmfr/30955495.

16.

Liu

Gao

, et al. Sonography for diagnosis of benign and malignant tumors of the nose and paranasal sinuses. J Ultrasound Med 2014; 33: 1627–1634. 2014/08/27. DOI: 10.7863/ultra.33.9.1627.

17.

Acar

Yolcu

Asutay

Is ultrasonography useful in the diagnosis of nasolabial cyst?

Case Rep Dent 2014; 2014: 678541. 2014/04/09. DOI: 10.1155/2014/678541.

18.

Sumer

Celenk

Sumer

, et al. Nasolabial cyst: case report with CT and MRI findings. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: e92–e94. 2009/12/26. DOI: 10.1016/j.tripleo.2009.09.034.

19.

Aquilino

Bazzo

Faria

, et al. Nasolabial cyst: presentation of a clinical case with CT and MR images. Braz J Otorhinolaryngol 2008; 74: 467–471. 2008/07/29. DOI: 10.1016/s1808-8694(15)30585-1.

20.

Chindasombatjaroen

Uchiyama

Kakimoto

, et al. Postoperative maxillary cysts: magnetic resonance imaging compared with computerized tomography. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 107: e38–e44. 2009/05/12. DOI: 10.1016/j.tripleo.2009.02.012.

21.

Iida

Aikawa

Kishino

, et al. Spheric mass beneath the alar base: MR images of nasolabial cyst and schwannoma. AJNR Am J Neuroradiol 2006; 27: 1826–1829. 2006/10/13.

22.

Hisatomi

Asaumi

Konouchi

, et al. MR imaging of nasopalatine duct cysts. Eur J Radiol 2001; 39: 73–76. 2001/08/28. DOI: 10.1016/s0720-048x(01)00279-0.

23.

Tanimoto

Kakimoto

Nishiyama

, et al. MRI of nasoalveolar cyst: case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2005; 99: 221–224. 2005/01/22. DOI: 10.1016/j.tripleo.2004.08.002.

24.

Ocak

Duman

Bayrakdar

, et al. Nasolabial cyst: a case report with ultrasonography and magnetic resonance imaging findings. Case Rep Dent 2017; 2017: 4687409. 2017/07/12. DOI: 10.1155/2017/4687409.

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