A Study on the Assessment of Haller Cells in Panoramic Radiograph.

CONTEXT: Haller cells are extensions of ethmoid cells which can be seen in several imaging modalities. Literature search has shown that idiopathic orofacial pain is associated with the presence of Haller cells. Hence, a simple cost-effective imaging modality for displaying the presence of Haller cells is desirable. AIMS: This study aims to determine the prevalence of Haller cells in panoramic radiography. SUBJECTS AND METHODS: The retrospective study comprised of 403 individuals of both genders. Panoramic radiograph was taken for every individual and interpreted for the presence of Haller cells. Factors incorporated in the interpretation were prevalence of Haller cells, distribution of Haller cells among genders, site predilection, unilocular or multilocular variant, and most common shape prevalent among the individuals. STATISTICAL ANALYSIS USED: Chi-square test with SPSS software.
RESULTS: Among 403 individuals, the Haller cells were present in 92 (22.8%) individuals. Of 92 (22.8%) individuals with Haller cells, 40 (18.5%) were males and 52 (27.8%) were females. Seventy-four individuals (80.4%) were unilocular and 18 (19.6%) were multilocular. Forty-five individuals had (48.9%) tear-shaped Haller cells, 27 (29.3%) had round-shaped Haller cells, and 20 (21.8%) had oval-shaped Haller cells. Forty (43.5%) were on the right side, 29 (31.5%) were on the left side, and 23 (25%) were on both sides.
CONCLUSIONS: The present study assessed the prevalence of Haller cells as 22.8%, and this was done in a cost-effective way using panoramic radiographs.

INTRODUCTION

Anatomical variations are common and different from one patient to another.1 To make a proper diagnosis of anatomical variations such as Haller cells, it should be noted and totally understood.1 Variations associated with ethmoidal cells during development are usually associated with inflammation and paranasal sinus surgeries.2 One such anatomic variation of concern in undiagnosed orofacial pain includes the presence of Haller cells. These cells are known as orbitomaxillary cells and first described by Albert Von Haller in 1743.2 As Haller cells arise from anterior ethmoidal cells and located medial to orbital floor, these are also called as infraorbital ethmoidal cells.3 In addition to undiagnosed orofacial pain, the cells are found to be associated with other disorders such as sinusitis, nasal obstruction, headache, cough, and mucoceles.4 An infection of these cells could result in headache, and it may further block ethmoidal infundibulum to cause maxillary sinusitis.5 This study was conducted to assess the prevalence of Haller cells and its possible significant role in etiology of orofacial pain disorders and lack of notable literature in terms of gender, age, shape, number, and distribution correlating the presence of Haller cells, especially in our environment.

SUBJECTS AND METHODS

The retrospective study consists of 403 individuals of both genders between the age group of 18 and 80 years. The study was conducted in the Department of Oral Medicine and Radiology, Best Dental Science College, Madurai. Institutional review board evaluated the study before the commencement, and approval was obtained. Panoramic views were taken using X-Mind Pano D+ with DIGORA® for Windows, the SOREDEX dental imaging software (Acteon., United Kingdom). Panoramic radiographs chosen in our study were taken for several orofacial disorders in our hospital between the periods of February 2016 and April 2016. Each radiograph was carefully interpreted for the presence of Haller cells. The interpretation and the criteria for choosing the Haller cells in a panoramic radiograph was obtained from the study conducted by Ahmad et al.6 The criteria for selection are listed below:

Well-defined round, oval, or tear drop-shaped radiolucency, single or multiple, unilocular or multilocular, with a smooth border, which might not appear corticated

Located medial to the infraorbital foramen

All or most of the borders of the entity in the panoramic section is visible

The inferior border of the orbit lacks cortication or remains indistinguishable in areas superimposed by this entity.

Factors incorporated in the interpretation of our study were prevalence of Haller cells, distribution of Haller cells among genders, site predilection, unilocular or multilocular variant, and the most common shape prevalent among the individuals. The data were scrutinized using IBM SPSS Software, IL, CH, USA with descriptive statistical methods.

RESULTS

The total sample size of the study was 403 individuals, of which Haller cells were present in 92 individuals (22.8%) [Table 1]. Among 92 (22.8%) individuals diagnosed with Haller cells, 40 (18.5%) were males and 52 (27.8%) were females [Table 2]. Among 92 individuals with Haller cells, 30 (37.0%) were between 20 and 30 years, 13 (15.9%) were between 31 and 40 years, 17 (21.2%) were between 41 and 50 years, 21 (26.2%) were between 51 and 60 years, and 11 (13.8%) were between 61 and 80 years [Table 3]. Among the total number of individuals available with Haller cells, 74 (80.4%) were unilocular and 18 (19.6%) were multilocular [Table 4]. On analyzing the shape of Haller cells, 45 (48.9%) were tear shaped [Figure 1], 20 (21.8%) were oval shaped [Figure 2], and 27 (29.3%) were round in shape [Figure 3 and Table 5]. Among the 92 individuals assessed in the present study, the Haller cells were found on the right side in 40 individuals, left side in 29 individuals, and on both sides in 23 individuals [Table 6].

Table 1

Prevalence of Haller cells in the orbital floor region

	Frequency (%)
Absent	311 (77.2)
Present	92 (22.8)
Total	403 (100.0)

Table 2

Distribution of Haller cells with respect to gender

Gender	Number of patients (%)	Total (%)
Male	40 (18.5)	216 (100)
Female	52 (27.8)	187 (100)

χ2=4.9, degree of freedom=1, P=0.02 (<0.05)

Table 3

Distribution of Haller cells with respect to age

Age group	Number of patients (%)	Total (%)
20-30	30 (37.0)	81 (100.0)
31-40	13 (15.9)	82 (100.0)
41-50	17 (21.2)	80 (100.0)
51-60	21 (26.2)	80 (100.0)
61-80	11 (13.8)	80 (100)

χ2=15.93, degree of freedom=4, P=0.003 (<0.05)

Table 4

Distribution of Haller cells with respect to pattern

Pattern	n (%)
Unilocular	74 (80.4)
Multilocular	18 (19.6)

Figure 1

Tear drop-shaped Haller cells in the right lower border of the orbital floor

Figure 2

Oval-shaped Haller cells in the right side lower border of the orbital floor

Figure 3

Round-shaped Haller cells in the right side lower border of the orbital floor

Table 5

Distribution of Haller cells with respect to shape

Shape	n (%)
Round	27 (29.3)
Tear	45 (48.9)
Oval	20 (21.8)

Table 6

Distribution of Haller cells with respect to side

Side	n (%)
Right	40 (43.5)
Left	29 (31.5)
Both	23 (25)

DISCUSSION

The prevalence of Haller cells varies with imaging techniques. A prevalence of 4.7%–45.1% has been reported in computed tomographic images, and in panoramic radiograph, the prevalence ranges between 16% and 38.9%.678 A study conducted by Valizadeh et al. in 310 panoramic radiographs showed the prevalence of Haller cells to be 37%.9 In our study, the prevalence of Haller cells in panoramic radiograph was 22.8%. Such variation happens as a result of variation within the sample size and observer variability in detecting the Haller cells.7 Gender variability of Haller cells in previously reported studies by Raina et al.7 and Khayam et al.8 were on the higher side compared to our study.

Out of 92 cases, majority of Haller cells (37%) was diagnosed between the age group of 20 and 30 years followed by 51 and 60 years (26.2%). The results were similar to the study conducted by Solanki et al. in which the majority of Haller cells were diagnosed between 18 and 28 years of age (33.3%).10 Of 92 cases, 74 (80.4%) were unilateral in our cases, and similar finding was found in the study conducted by Ghaffari et al. in which 90.9% cases had unilocular Haller cells.11 Of 92 cases, 45 (48.9%) cases had tear-shaped Haller cells followed by round 27 (29.3%) and oval 20 (21.8%) cases [Figures 1–3]. However, according to the [Figure 3] study conducted by Ramaswamy et al.,12 the most common shape in their study was round (60.3%), and Solanki et al.10 also found similar kind of results in their study with most common shape being round or oval with few tear-shaped Haller cells.

Of 92 cases in our study, 40 cases had Haller cells on the right side, 29 cases on the left side, and 23 cases on both sides. However, in other studies, there were no significant difference found between the presence of Haller cells and sides.36

CONCLUSIONS

The present study assessed the prevalence of Haller cells as 22.8%, and this was done in a cost-effective way using panoramic radiographs. This would aid in determining Haller cells as an etiological factor for the chronic orofacial pain with undiagnosed etiology. Further validation of the study may require a voxel three-dimensional (3D) interpretation rather than a pixel 2D imaging techniques at specific clinical scenarios to aid in proper diagnosis and formulating treatment protocol for the patients with orofacial pain.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.