J Vet Clin 26(4) : 371-375 (2009)

Sialocele with in a Beagle Dog

Young-Hang Kwon, Soo-Ji Lim, Jin-Hwa Chang, Ji-Young An, Se-Joon Ahn, Seong-Mok Jeong, Seong-Jun Park, Sung-Whan Cho, Ho-Jung Choi and Young-Won Lee1 College of Veterinary Medicine · Research Institute of Veterinary Medicine, Chungnam National University, Daejeon 305-764, Korea

(Accepted : August 19, 2009)

Abstract : A three-year-old Beagle dog was presented with the neck mass. Mass was located at ventral part of the . The dog showed excessive . with calculi was evaluated based on physical exam, radiographs, ultrasonography, and computed tomography. resection was performed. Histopathological examination confirmed sialoadenitis concurred with sialocele. Key words : Sialocele, radiograph, ultrasonography, sialolithiasis, sialoadenitis.

Introduction Hyperechoic materials accompanying acoustic shadow also were detected on the dependent portion of cavitary lesion Sialocele, or salivary mucocele is an accumulation of (Fig 2-B). The hyperechoic objects were suspected as intrag- in subcutaneous tissue due to tear in a salivary gland or duct landular sialoliths, which were shown on the radiographs. No and often occurs in dogs (7). Sialolithiasis is defined as the evidence of vascularization was detected. FNA was per- formation of calcified secretions in a salivary gland or duct, formed guided by ultrasound. Aspirated samples of the and is infrequent as compared with salivary mucocele (23). swelling lesion showed viscous, lucent, and hazy contents. Painless swelling of the neck and oral cavity is the most RBCs and inflammatory cells were detected on the micro- common clinical signs associated with salivary gland abnor- scopic study. Additionally amorphous mucoid materials which malities in the dog and cat (7). Diagnosis of salivary gland stained in pinkish are detected throughout the slide, sugges- lesions are based on physical examination, , ultra- tive of saliva. Computed tomography (CT) was performed sonography, and fine needle aspiration (FNA) (14). with a third generation scanner (5 mm contiguous slices) in This report describes clinical signs, imaging diagnoses and sternal position. On the CT examination, septated fluid-filled treatment of sialocele concurred with sialolith and inflamma- mass which has a little contrast-enhancement was detected tion. right side of ventral part at tympanic cavity level (Fig 3). They were contiguous with a tubular structure of a fluid den- Case sity that became increasingly dilated, bifurcated, and contin- ued on to the mandibular salivary gland. Hyperintense objects A 3-year-old male Beagle dog was presented with hyper- suspected sialolith which were located in ventral part of the salivation and cervical mass on the ventral part of mandible. mandibular gland were shown (Fig 3). Considering these imag- On clinical examination, a freely mobile, soft, fluctuant, and ing findings, the stones are freely movable materials which nonpainful mass, measuring 8 × 6 × 3 cm was palpable. The are dependent to gravity due to variable locations on different mass located right-sided when the patient was in dorsal positions. Sialoadenectomy of mandibular gland was per- recumbent position. Blood examinations results showed unre- formed with drainage placement. Two white and firm calculi markable findings. Soft tissue swelling on ventral side of the were detected in the intraluminal surface of resected gland neck was detected on the lateral skull radiography. Small (Fig 4). The resected mandibular gland appeared as inflamed radiopaque materials were identified within the mass (Fig 1). sialocele on the histopathological examination. Infiltrated There were no remarkable findings on the thoracic radio- inflammation cells were detected on the interstitial tissue. In graphs. Enlarged, septated cavitary lesion containing echogenic addition, fibrous tissue and RBCs were shown on the micro- fluid contents were shown on the ultrasonography (Fig 2-A). scopic examination (Fig 5). The patient was discharged after 5th day of hospitalization according to no specific findings on 1Corresponding author. blood examination results and sparse drainage on the lesion. E-mail : [email protected] No recurrence was detected after surgery.

371 372 Young-Hang Kwon et al.

Fig 1. Right lateral radiograph (A) of the skull part. Magnified image of Figure 1-A (B). Soft tissue swelling ventral to the cervical part is noted containing radiopaque materials (white circle) inside the mass.

Fig 2. Septated masses with echogenic contents were shown on the ultrasonographic examination (A). Note the hyperechoic foci (arrows) dorsal to the lesion which accompanied with weak acoustic shadowing (B).

Fig 3. Transverse CT scans at the level of (A) and 10 mm cranial to Figure 3-A (B) using a soft tissue win- dow. Hypodense septated mass was shown on the ventral side. The hyperdense material (arrow) was observed on the ventral part of mass lesion. Sialocele with Sialolithiasis in a Beagle Dog 373

ally painless, fluctuant swellings (7). If the animal is examined during the initial inflammatory phase, the patient will show pain on the physical examination (14). There are four paired major salivary glands in dogs (8). These are the parotid, mandibular, sublingual, and zygomatic glands (8). Sialolith has only been reported in 8 cases in vet- erinary medicine (4,12,13,17,19,23). To the authors knowl- edge, 6 cases occurred in (4,12,13,23), 1 case was in (19), and 1 case in cervical region suspecting as mandibular mucocele (1). Poodles, German shepherds, dachshund, and Australian silky terriers are more commonly affected (11). Additionally, Beagle, Maltese, English Bulldog, and English Springer Spaniel were also been reported (1,4,14). There is a slight predisposition for males to be affected (11). This case was occurred in mandibular sali- vary gland in a male Beagle dog. Diagnoses of are based on radiogra- Fig 4. The was shown on the intraluminal surface of the phy, ultrasonography, CT, FNA and finally by histopatholog- gland. The calculus was white, chalky, and rough in appearance. ical examination (14). has been used to identify affected glands and ducts, however, difficult to perform and Discussion is usually unnecessary (7). Ultrasonography and FNA are good modalities for diagnosing salivary gland lesions. Otherwise The incidence of canine sialoceles is less than one in 200 some authors suggest CT could provide more information than dogs (21). Trauma is believed to be the inciting cause of a ultrasonography (4). tear in salivary gland or duct which leads to the formation of Ultrasonography of the salivary gland provides informa- a sialocele (7). This trauma may be due to any blunt trauma, tion on the site, nature and extent of pathology, and also for a foreign body, or a sialolith (11,23). guidance of FNA or core biopsy (2). Normal mandibular sal- Canine sialolithiasis is an infrequently diagnosed clinical ivary gland has a fine and moderate echogenicity surrounded condition, although on histopathological study of salivary by a thin echogenic capsule, otherwise parotid gland appears gland disease in 245 dogs and cats reported an incidence of as a poorly margined structure of moderately low echogenicity 0.4 percent (19,22). The etiology of salivary stones has not and with more heterogeneous parenchyma (24). Cystic lesions, been clearly understood, however several theories have been such as sialoceles or salivary cysts appear as hypoechoic or proposed, including the excretion of microcalculi by the aci- anechoic regions within the salivary gland (24). Sialoliths nar cells and the presence of intraluminal mucous plugs or appear as hyperechoic foci casting far-field acoustic shadow- inflammatory debris possibly from bacterial migration and ing (2). Although those smaller than 2 mm may not cause secondary inflammation that may act as an organic nidus for acoustic shadowing (2). Only about 20% of sialoliths are deposition of inorganic components (4,5,16). Sialolith forma- radiopaque in human medicine (3,18). In human, the ultra- tion may both be a cause for and result of salivary retention sound has a high degree of accuracy (96%) in their diagnosis (4,9,18). (2, 10). Chronic inflammatory lesions are seen as small cystic Presenting complaint of the patient depends on the loca- areas or an inhomogeneous echo pattern owing to inflamma- tion of the sialocele (14). Usually cervical sialoceles are usu- tion and reactive hyperplasia of intraglandular lymphatic tis-

Fig 5. Histopathological examination of the resected glands. Infiltration of the inflammatory cells, such as lymphocytes is shown. Fibrosis (arrow) and granulation tissues are detected. 374 Young-Hang Kwon et al. sue (24). major salivary glands: anatomy and spatial relationships, Aspiration may verify the salivary nature of these cystic pathologic conditions, and pitfalls. Radiographics 2006; 26: lesions (15,24). Cytologic evaluation of sialocele aspirates usu- 745-63. ally reveals diffuse or irregular clumps of homogenous pink 4. Brian JT, Kyleigh G, Kyle GM. sialolithiasis in to violet staining mucin (20). Additionally, CT provides more a dog. J Am Anim Hosp Assoc 2007; 43: 45-51. 5. Bsoul SA, Flint DJ, Terezhalmy GT, et al. Sialolithiasis. informations than plain radiographs regarding status of the Quintessence Int 2003; 34: 316-7. duct and glands, and the exact location of the radiographic 6. Chastain CB, Grier RL. What is your diagnosis? J Am Vet opacity of sialoliths (4). Sialolithiasis was easily evaluated by Med Assoc 1974; 164: 415-416. various imaging modalities in this case. Furthermore, appear- 7. Dianne D. Oral cavity. In: Slatter D. Textbook of Small ance and nature of the lesion and its distribution were also Animal Surgery. 3rd ed. Saunders. 2001; 553-72. simply identified by the diagnostic examinations. 8. Evans HE. The digestive apparatus and abdomen. In: Evans Differential diagnosis lists of sialoceles would be consid- HE. Miller's Anatomy of the Dog. 3rd ed. WB Saunders. 1993; ered as sialoladenitis, salivary neoplasia, sialolith, foreign 385-462. body, granuloma, hematoma, cystic or neoplastic lymph nodes, 9. Grases F, Santiago C, Simonet BM, et al. Sialolithiasis: cystic Rathke's pouch, and branchial cyst (11). These differ- mechanism of calculi formation and etiologic factors. Clin ential lists would be ruled out through physical examination Chim Acta 2003; 334: 131-6. 10. Gritzmann N. Sonography of the salivary glands. Am J and other diagnostic modalities. However, histopathological Roentgenol 1989; 53: 161-6. examination is necessary to diagnose salivary gland tumors 11. Hedlund CS. Fossum TW. Surgery of the digestive system. and to differentiate a congenital cyst from a sialocele (11). In: Fossum TW, Hedlund CS, et al. Small Animal Surgery. Treatment of salivary gland lesion is indicated as removal 2nd ed. Mosby. 2002; 274-449. of the affected glands (7). After resection of the glands and 12. Hunt GB, Youmans KR, et al. Retropharyngeal pain and ducts, the mucocele should be drained (7). Recurrence of any swelling in a dog. Aust Vet J 1997; 75: 476,491. mucocele is uncommon (< 5%) after salivary gland resection 13. Jeffreys DA, Stasiw A, Dennis R. Parotid sialolithiasis in a unless the affected gland has not been completely resected dog. J Small Anim Pract 1996; 37: 296-7. (7). Likewise no recurrence was observed in this patient. 14. Mackey P, Hart R. Canine sialoceles. Cornell Univ College This report describes sialocele with sialolithiasis and sia- of Vet Med Senior Seminar Paper 2003. loadenitis. Radiography was efficient to detect salivary calculi 15. Mandel L, Hatzis G. The role of computerized tomography in the diagnosis and therapy of parotid stones: a case report. in this case. Extent of the lesion and its pathologic condi- J Am Dent Assoc 2000; 131: 479-82. tions of the gland could be determined by ultrasonographic 16. Marchal F, Kurt AM, Dulguerov P, et al. Retrograde theory examination. Paracentesis of the mass helped to differentiate in sialilithiasis formation. Arch Otolaryngol Head Neck Surg between differential diagnoses. CT was a useful tool for eval- 2001; 127: 66-8. uating the exact location of sialolithiasis. Also its advantages 17. Mulkey OC, Knecht CD. Parotid salivary gland cyst and were the ability of scan to assess the secondary status of the calculus in a dog. J Am Vet Med Assoc 1971; 159: 1774. gland, such as sialoadenitis and abscess (15), and to determine 18. Rausch S, Gorlin RJ. Diseases of the salivary glands. In: lesion distribution. Gorlin RJ, Golman HM, eds. Thoma's Oral Pathology. St. Louis: CV Mosby, 1970: 962-1003. Conclusion 19. Ryan T, Welsh E, McGorum I, and Yool D. Sublingual salivary gland sialolithiasis in a dog. J Small Anim Pract 2008; 49: 254-6. This case reports about the diagnosis and treatment of sal- 20. Shull RM, Maddux JM. Subcutaneous glandular tissue. In: ivary gland disease, especially, sialocele, sialolithiasis, and Rick LC, Ronald DT, James HM. Diagnostic Cytology and sialoadenitis. Diagnoses were carried out by radiography, Hematology of the Dog and Cat. 2nd ed. Mosby. 1999; 88-96. ultrasonography, FNA, and CT. Sialoadenectomy of mandib- 21. Smith MM. Oral and salivary gland disorders. In: Ettinger ular gland was performed for treating surgically. Prognosis SJ, Feldman EC. Textbook of Veterinary Internal Medicine. was good. Ultrasonography and FNA would be the appropri- 6th ed. Elsevier Saunders. 2000; 1290-7. ate choice for the diagnosis of salivary gland diseases. 22. S pangler WL, Culbertson MR. Salivary gland disease in dogs and cats: 245 cases (1985-1988). J Am Vet Med Assoc 1991; References 198: 465-9. 23. Termote S. Parotid salivary duct mucocele and sialolithiasis 1. Aita N, Sakawa Y, Hideo I. Sialocele with sialolithiasis in following parotid duct transpostion. J Small Anim Pract 2003; a dog. J Jap Vet Med Assoc 2006; 59(10): 687-9 44: 21-3. et al 24. Wisner ER, Mattoon JS, Nyland TG. Neck. In: Nyland GN, 2. Alyas F, Lewis K, Williams M, . Disease of the nd as demonstrated using high resolution Mattoon JS. Small Animal Diagnostic Ultrasound. 2 ed. WB ultrasound. Br J Radiol 2005; 78: 362-9. Saunders. 2002; 285-304. 3. Bialak EF, Fakubowski W, Zajkowski P, et al. US of the Sialocele with Sialolithiasis in a Beagle Dog 375

비글견에서 발생한 타액선 결석과 타액선류 증례

권영항·임수지·장진화·안지영·안세준·정성목·박성준·조성환·최호정·이영원1 충남대학교 수의과대학·동물의과학연구소

요약:3년령의 비글견이 경부 종괴로 내원하였다. 종괴는 하악의 배쪽 부분에 위치하였다. 환자는 심한 유연 증상을 보였다. 신체 검사, 방사선 검사, 초음파 검사와 컴퓨터단층촬영 결과 타액선 결석과 함께 타액선류로 진단되었다. 타 액선 제거술이 수행되었다. 조직병리학적 검사로 타액선 염증과 타액선류로 진단되었다. 주요어 : 타액선류, 방사선 검사, 초음파 검사, 타액선 결석, 타액선염.