- Email: [email protected]
Congenital abnormalities of the submandibular duct
lntrrnational Journal of Pediatric Otorhinolaryngol~~~l, 24 (19Y2) lhl- 169 K’ 1992 Elsevier Science Publishers B.V. All rights reserved 0165-587h/92/$OS.O0
PEDOT
Ihl
00800
Congenital abnormalities of the submandibular duct * Patrick
H. Pownell
‘, Orval E. Brown ‘, Seth M. Pransky and Scott C. Manning ’
’
’ Department qf Otorhinolaryngology, UniL’ersityof Te.ras Southwestern Medical Center ut Dullus. Dalltrs. TX CUSA) und ’ Pediatric Otolaryngology Associates, Inc., 3030 Children’s Way, No. 402. San Dicgo, CA (USA) (Received 21 August 1991) (Revised version received 1 Novemher (Accepted 9 November 190 I)
Kr\, words: Congenital duct
imperforate
submandibular
duct:
Ranula;
1991)
Duplication
anomaly
of Wharton’\
Abstract
Five newborns presented with cystic lesions of the floor of mouth. Four of these patients proved to have congenitally imperforate submandibular salivary gland ducts and the other newborn proved to have a duplication anomaly of the submandibular gland duct and gland. The patients with imperforate Wharton’s ducts underwent marsupialization with or without ductoplasty and have been without evidence of recurrence for up to three years. The duplication anomaly of the submandibular gland duct responded to simple excision. The diagnosis of congenital anomalies of the submandibular gland and duct can be made on physical examination. Magnetic resonance imaging can be helpful in differentiating congenital imperforate submandibular duct and duplication anomalies of the ductal system. Treatment of the former consists of duct marsupialization in the floor of mouth with or without ductoplasty. Treatment of the duplicated ductal system may best be treated with excision. A failure in diagnosis and treatment may result in ranula formation or sialoadenitis requiring more extensive therapy.
Correspondence to: O.E. Brown, Department of Otorhinolatyngology, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd.. Dallas. TX 75235-9035, USA. * Presented, in part, at the Annual Meeting of the Society of Ear. Nose. and Throat Advances in Children, Washington, DC, December 1990.
162
Introduction Congenital abnormalities of the submandibular glomus duct are rarely reported. An early reported case of congenital imperforate submandibular gland ducts was in 1955 by Scher and Scher [12] who noted a newborn with bilateral cystic lesions in the floor of mouth consistent with bilateral Wharton’s duct obstruction. Simple incision of the fluid filled sacs was curative. In 1968, Dore [3] reported a series of four cases of infants with unilateral congenital dilation of the submandibular ducts: excision of the terminal portion of the duct with ductoplasty was curative in all cases. Redpath [lo] in 1969 reported a newborn with congenital atresia of the right submandibular duct with ranula formation. Marsupialization again was curative. Foretich [5] reported another case in 1973 in which a lo-week-old infant presented with bilateral floor of mouth ranulas associated with ankyloglossia. Decompression with ductoplasty and stenting for 5 days was effective therapy for both ducts. In 1984, Addante [ll reported another case of congenital cystic dilation of the submandibular duct associated with ankyloglossia. This was treated with excision of the anterior aspect of the duct and ductoplasty (Table I). The first reported case of a duplication anomaly of the submandibular duct was in 1932 by Rose [ll] who reported an accessory duct just beyond the normal puncta with accompanying sialoadenitis tissue in a 34-year-old female. Since that
TABLE
I
Imperforate submandibular gland ducts Date
Author
Cases
Treatment
1955 1968 1969 1973 1984 1991
Scher [12] Dore [3] Redpath [lo] Foretich [5] Addante [l] Pownell
1 Bilateral 4 Unilateral 1 Unilateral 1 Bilateral 1 Unilateral 3 Unilateral 1 Bilateral
Marsupialization Excision of terminal duct and ductoplasty Marsupialization Excision of terminal duct and ductoplasty Marsupialization Marsupialization Marsupialization and ductoplasty
TABLE
II
Duplication anomalies of the submandibular gland duct Date
Author
1932 1966 1973 1973
Rose [ll] Myerson [8] Rahmathulla Jafek [6]
1977 1986 1991
Towers [13] Mori [7] Pownell
[91
34 22 14 68 65 50 73 NB
Presentation
Treatment
Sialoadenitis Sialogram Sialogram Sialogram Sialogram Sialogram Sialogram Ranula
Excision None None None None None None Excision
Fig. I. Case 1: bilateral
cystic lesions
in the anterior floor of mouth ducts.
due to imperforate
submandibula
time, six other cases of duplications of the submandibular gland duct have been reported [6-131 (Table II). All of these remaining cases have been in asymptomatic adults or adolescents noted as incidental findings on submandibular sialograms. We report three cases of unilateral imperforate submandibular gland ducts and another case of congenital bilateral imperforate submandibular gland ducts. Also, we report a not previously described case of a newborn infant presenting with a unilateral floor of mouth fluid-filled cyst due to a duplication anomaly of the submandibular gland duct.
Case 1
A healthy newborn white female with an uneventful prenatal history was noted in the first few days of life to have bilateral cystic dilations located in the anterior floor of mouth (Fig. 1). These fluid filled sacs were non-tender and had no evidence of inflammation. No palpable calculi could be found. No history of birth trauma or previous injury to this area could be elicited. Additionally, no fluid could be detected arising from the submandibular gland with palpation. The patient underwent examination under anesthesia and neither orifice of the submandibular duct could be identified in the anterior floor of mouth and a diagnosis of bilateral imperforate submandibular ducts was made. Each terminal duct was then incised
164
Fig.
2. Case
1: postoperative
view
of marsupialization and submandibular ducts.
ductoplasty
of bilatel ral
:rfo1 .ate
and the terminal submandibular duct marsupialized (Fig. 2). The marsupialization of each duct was completed by a ductoplasty with plication of the anterior and posterior free edges to the floor of mouth with absorbable suture. Adequate and brisk flow of saliva was achieved from both glands. The postoperative course has been uneventful without evidence of recurrence or duct stenosis at one year.
Case 2
A two-month-old term white female born of an uneventful prenatal history was referred for evaluation of a draining sinus tract along the anterior right sternoclei-
Fig. 3. Case 2: right-sided
cystic dilation
in the floor of mouth duct.
of unilateral
imperforate
submandibular
domastoid muscle consistent with a second branchial cleft sinus. Additionally, the mother reported a slowly enlarging fluid-filled cystic mass in the right floor of mouth which was now causing some feeding problems (Fig. 3). No known previous trauma was reported in this area. Examination of the floor of mouth revealed a fluid-filled cystic mass and no identifiable Wharton’s ducts on this side. Simple incision was performed in the office with an 18-gauge needle to accomplish adequate marsupialization and complete resolution of the cyst. Brisk salivary flow was easily detected after this procedure. The office procedure has been without evidence of recurrence for 4 months. Excision of the branchial cleft sinus will be planned at about 12 months of age.
Case 3 A healthy term newborn with an uneventful prenatal history was seen with a left sided cystic mass in the floor of mouth. No patent terminal submandibular duct orifice was identified, and a diagnosis of left imperforate submandibular duct was made. Marsupialization was performed as an office outpatient procedure with resultant brisk flow of saliva. Ductoplasty or stenting was not performed. Short-term follow up reveals patient salivary flow into the floor of mouth and no evidence of recurrence.
166
Case 4
A one-month-old was referred with a history of a cyst under her tongue, which had been present at birth. The patient was otherwise healthy. Examination revealed an enlarged and dilated left submandibular duct with an imperforate terminal end. There were no other abnormalities. The patient underwent marsupialization of the left imperforate submandibular duct with a ductoplasty consisting of tacking the everted edges of the duct to the floor of mouth with small absorbable sutures. Free flow of saliva was obtained. The patient has done well with no evidence of restenosis or obstruction of her left submandibular duct in several months of follow-up.
Case 5
A one-week-old white male was noted to have a slowly enlarging cyst-like lesion in the left floor of mouth. Needle decompression was initially performed with removal of 3 ml of seromucinous fluid. One week later, the cyst had recurred and was impairing the infant’s ability to feed. A magnetic resonance imaging scan was obtained which revealed increased signal intensity extending from the left submandibular gland to the floor of mouth (Fig. 4). One week later, this lesion was
Fig. 4. Case 5: magnetic
resonance
imaging revealing fluid filled accessory gland located anteriorly.
duct with displaced
normal
I67
excised and the surgical findings revealed a cyst extending to the submandibular gland which was separate from the true submandibular duct. Pathologic diagnosis was a benign epithelial cyst lined with non-ciliated stratified columnar epithelium, consistent with a ductal structure. The postoperative course has been uneventful without evidence of recurrence in over one year.
Discussion
The submandibular gland arises from proliferation and ingrowth of ectodermal cells in the oral cavity beginning at about the 10th to the 12th gestational week [41. Further differentiation takes place with development of the acinar complexes and the ductal system until full term. One of the last processes to occur in development is the hollowing of the epithelial tissue to allow for a patent ductal system. If this hollowing fails to occur at the terminal aspect of the duct, imperforation of Wharton’s duct occurs allowing for the development of these described floor of mouth lesions. Also, if the developing duct were to invaginate in two places, or if premature ventral branching of the duct were to occur, duplication anomalies of the duct and gland would be seen [6]. This is believed to be the etiologic factor in our last reported case. A ranula is broadly defined as a cystic tumor of the tongue or floor of mouth. It can be a fluid-filled mass associated with the obstruction of a minor salivary gland, or due to obstruction of the submandibular duct [2]. In the minor salivary gland associated lesion, the wall of the cyst consists of fibrous connective tissue and granulation tissue due to the escape of saliva into the surrounding tissue. With this lesion, simple incision leads to a high degree recurrence and the lesion must be excised. Conversely, the floor of mouth lesion that arises from obstruction of the duct is not connective tissue lined, but is lined by the epithelium of the ductal system. In this setting, simple marsupialization usually is satisfactory treatment and excision is not required. Patients with congenital submandibular duct obstruction must be treated in a timely fashion to prevent progressive dilation of the duct with ranula formation. Potential exists for infection of static saliva in the duct with sialoadenitis requiring incision and drainage and antibiotic therapy. Early marsupialization and ductoplasty can prevent these complications. To date, eight cases of imperforate submandibular ducts have reported. All of the cases have responded with a form of marsupialization with or without ductoplasty. This lesion may be more common than reported, as simple marsupialization seems adequate treatment. Additionally, some of these imperforate ducts may resolve spontaneously if rupture takes place with the trauma associated with sucking. Stenting of the ducts as done by Foretich [5] probably is not necessary if effective ductoplasty is performed to prevent stenosis. Also, stenting may be detrimental if stenosis results from the use of stents in the proximal ductal system. Although, these lesions may respond well to simple incision alone, we recommend marsupialization as adequate treatment. Ductoplasty may be beneficial in maintaining long-term patency.
168
Our last case represents a duplication anomaly of the submandibular duct with obstruction of the accessory duct and gland with ranula formation. A displaced, but present, submandibular gland was noted on the magnetic resonance imaging scan and the patency of the normal duct was confirmed in the operating room. MRI scanning clearly visualized the abnormal duplicated duct, and seems valuable in the diagnosis of these lesions. We have no experience with CT scanning in these lesions. As MRI scanning is done without radiation, it seems a safe and cost-effective radiologic diagnostic procedure when a physician is faced with floor of mouth lesions such as this. The lining of this cystic structure was ductal tissue confirming that this lesion was in fact an obstructed accessory duct. In our case, excision of the duplicated duct and gland was curative. Since most previously reported cases of duplication anomalies of the submandibular duct system have been in asymptomatic patients, treatment must be individualized to the pathologic process to which the duct is involved.
Conclusion This report describes one bilateral case and three unilateral cases of imperforate submandibular ducts. The bilateral case and one unilateral case were successfully treated with marsupialization and ductoplasty. Two of the unilateral cases responded to simple incision of the fluid-filled duct. This lesion is presumed due to incomplete cannulization of the terminal end of the duct. Only eight cases of this lesion have previously been reported and each responded with some form of marsupialization. This lesion may actually be more common than suggested by review of the literature, as simple incision to establish patency can be curative. Patients with imperforate submandibular ducts should be treated with early marsupialization to assure patency of the duct and prevent further complications such as ranula formation or sialoadenitis. Ductoplasty may be helpful in assuring long-term patency, but it is not clear if this procedure is helpful because of the small number of cases reported and short-term follow up. Ductoplasty would seem to add little morbidity to the procedure, and should be considered on an individual case basis. The last case is a previously unreported lesion in a newborn consisting of a duplication anomaly of the submandibular duct with cystic dilation and ranula formation. These lesions are best treated with complete excision of the cystic duplication lesion and careful preservation of the submandibular duct.
References 1 Addante, R.R., Congenital cystic dilation of the submandibular duct, Oral Surg., 59 (1984) 656-658. 2 Cummmings, C.W. et al., Otolaryngology-Head and Neck Surgery, C.V. Mosby, St. Louis, 1986, p. 1440. 3 Dore, P. and Dozin, A., False ranula of the newborn or imperforation of Wharton’s duct, Rev. Stomatol. (Paris), 69 (1968) 219-226.
IhY
4 El-Mohandes, E.A. et al., Prenatal development of the human submandibular gland. Acta Anat. I30 (1987) 213-218. 5 Foretich. E.A. et al., Bilateral congenital absence of the submandibular duct orifices.. J. Oral Surp.. 31 (1973) 556-557. 6 Jafek, B.W. and Strifo, J.L., Accessory lobe of the submandibular glands. Radiology, 109 tIY7il 75-77. 7 Mori. S. et al., Accessory duct in the submandibular gland. Oral Surg. Oral Med. Oral Pathol. 62 (19%) 607-608. X Myenson. M. et al., Bilateral duplication of the suhmandihular ducts. Arch. Otolaryngol.. 83 ( IYhh) 488-490. Y Rahmothulla, M., A rare case of accessory duct in submandibular sialography. J. Ind. Dental Assoc.. 4s (1973) 563-564. 10 Redpath. T.H., Congenital ranula, Oral Surg., 31 (lY73) 446-557. 11 Rose, Ben-Henry, Bifunction of the submaxillary duct, Am. J. Surg. I7 (1932) 257-258. 12 Scher, L.B. and Scher. I., Case of imperforate submandibular ducts in an infant. Br. Dent. _I.. YX (1955) 324. 13 Towers. J.F., Duplication of the submandibular salivary duct. Oral Surg. Oral Med. Oral Pathol.. 44 (1977) 320.
PEDOT
Ihl
00800
Congenital abnormalities of the submandibular duct * Patrick
H. Pownell
‘, Orval E. Brown ‘, Seth M. Pransky and Scott C. Manning ’
’
’ Department qf Otorhinolaryngology, UniL’ersityof Te.ras Southwestern Medical Center ut Dullus. Dalltrs. TX CUSA) und ’ Pediatric Otolaryngology Associates, Inc., 3030 Children’s Way, No. 402. San Dicgo, CA (USA) (Received 21 August 1991) (Revised version received 1 Novemher (Accepted 9 November 190 I)
Kr\, words: Congenital duct
imperforate
submandibular
duct:
Ranula;
1991)
Duplication
anomaly
of Wharton’\
Abstract
Five newborns presented with cystic lesions of the floor of mouth. Four of these patients proved to have congenitally imperforate submandibular salivary gland ducts and the other newborn proved to have a duplication anomaly of the submandibular gland duct and gland. The patients with imperforate Wharton’s ducts underwent marsupialization with or without ductoplasty and have been without evidence of recurrence for up to three years. The duplication anomaly of the submandibular gland duct responded to simple excision. The diagnosis of congenital anomalies of the submandibular gland and duct can be made on physical examination. Magnetic resonance imaging can be helpful in differentiating congenital imperforate submandibular duct and duplication anomalies of the ductal system. Treatment of the former consists of duct marsupialization in the floor of mouth with or without ductoplasty. Treatment of the duplicated ductal system may best be treated with excision. A failure in diagnosis and treatment may result in ranula formation or sialoadenitis requiring more extensive therapy.
Correspondence to: O.E. Brown, Department of Otorhinolatyngology, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd.. Dallas. TX 75235-9035, USA. * Presented, in part, at the Annual Meeting of the Society of Ear. Nose. and Throat Advances in Children, Washington, DC, December 1990.
162
Introduction Congenital abnormalities of the submandibular glomus duct are rarely reported. An early reported case of congenital imperforate submandibular gland ducts was in 1955 by Scher and Scher [12] who noted a newborn with bilateral cystic lesions in the floor of mouth consistent with bilateral Wharton’s duct obstruction. Simple incision of the fluid filled sacs was curative. In 1968, Dore [3] reported a series of four cases of infants with unilateral congenital dilation of the submandibular ducts: excision of the terminal portion of the duct with ductoplasty was curative in all cases. Redpath [lo] in 1969 reported a newborn with congenital atresia of the right submandibular duct with ranula formation. Marsupialization again was curative. Foretich [5] reported another case in 1973 in which a lo-week-old infant presented with bilateral floor of mouth ranulas associated with ankyloglossia. Decompression with ductoplasty and stenting for 5 days was effective therapy for both ducts. In 1984, Addante [ll reported another case of congenital cystic dilation of the submandibular duct associated with ankyloglossia. This was treated with excision of the anterior aspect of the duct and ductoplasty (Table I). The first reported case of a duplication anomaly of the submandibular duct was in 1932 by Rose [ll] who reported an accessory duct just beyond the normal puncta with accompanying sialoadenitis tissue in a 34-year-old female. Since that
TABLE
I
Imperforate submandibular gland ducts Date
Author
Cases
Treatment
1955 1968 1969 1973 1984 1991
Scher [12] Dore [3] Redpath [lo] Foretich [5] Addante [l] Pownell
1 Bilateral 4 Unilateral 1 Unilateral 1 Bilateral 1 Unilateral 3 Unilateral 1 Bilateral
Marsupialization Excision of terminal duct and ductoplasty Marsupialization Excision of terminal duct and ductoplasty Marsupialization Marsupialization Marsupialization and ductoplasty
TABLE
II
Duplication anomalies of the submandibular gland duct Date
Author
1932 1966 1973 1973
Rose [ll] Myerson [8] Rahmathulla Jafek [6]
1977 1986 1991
Towers [13] Mori [7] Pownell
[91
34 22 14 68 65 50 73 NB
Presentation
Treatment
Sialoadenitis Sialogram Sialogram Sialogram Sialogram Sialogram Sialogram Ranula
Excision None None None None None None Excision
Fig. I. Case 1: bilateral
cystic lesions
in the anterior floor of mouth ducts.
due to imperforate
submandibula
time, six other cases of duplications of the submandibular gland duct have been reported [6-131 (Table II). All of these remaining cases have been in asymptomatic adults or adolescents noted as incidental findings on submandibular sialograms. We report three cases of unilateral imperforate submandibular gland ducts and another case of congenital bilateral imperforate submandibular gland ducts. Also, we report a not previously described case of a newborn infant presenting with a unilateral floor of mouth fluid-filled cyst due to a duplication anomaly of the submandibular gland duct.
Case 1
A healthy newborn white female with an uneventful prenatal history was noted in the first few days of life to have bilateral cystic dilations located in the anterior floor of mouth (Fig. 1). These fluid filled sacs were non-tender and had no evidence of inflammation. No palpable calculi could be found. No history of birth trauma or previous injury to this area could be elicited. Additionally, no fluid could be detected arising from the submandibular gland with palpation. The patient underwent examination under anesthesia and neither orifice of the submandibular duct could be identified in the anterior floor of mouth and a diagnosis of bilateral imperforate submandibular ducts was made. Each terminal duct was then incised
164
Fig.
2. Case
1: postoperative
view
of marsupialization and submandibular ducts.
ductoplasty
of bilatel ral
:rfo1 .ate
and the terminal submandibular duct marsupialized (Fig. 2). The marsupialization of each duct was completed by a ductoplasty with plication of the anterior and posterior free edges to the floor of mouth with absorbable suture. Adequate and brisk flow of saliva was achieved from both glands. The postoperative course has been uneventful without evidence of recurrence or duct stenosis at one year.
Case 2
A two-month-old term white female born of an uneventful prenatal history was referred for evaluation of a draining sinus tract along the anterior right sternoclei-
Fig. 3. Case 2: right-sided
cystic dilation
in the floor of mouth duct.
of unilateral
imperforate
submandibular
domastoid muscle consistent with a second branchial cleft sinus. Additionally, the mother reported a slowly enlarging fluid-filled cystic mass in the right floor of mouth which was now causing some feeding problems (Fig. 3). No known previous trauma was reported in this area. Examination of the floor of mouth revealed a fluid-filled cystic mass and no identifiable Wharton’s ducts on this side. Simple incision was performed in the office with an 18-gauge needle to accomplish adequate marsupialization and complete resolution of the cyst. Brisk salivary flow was easily detected after this procedure. The office procedure has been without evidence of recurrence for 4 months. Excision of the branchial cleft sinus will be planned at about 12 months of age.
Case 3 A healthy term newborn with an uneventful prenatal history was seen with a left sided cystic mass in the floor of mouth. No patent terminal submandibular duct orifice was identified, and a diagnosis of left imperforate submandibular duct was made. Marsupialization was performed as an office outpatient procedure with resultant brisk flow of saliva. Ductoplasty or stenting was not performed. Short-term follow up reveals patient salivary flow into the floor of mouth and no evidence of recurrence.
166
Case 4
A one-month-old was referred with a history of a cyst under her tongue, which had been present at birth. The patient was otherwise healthy. Examination revealed an enlarged and dilated left submandibular duct with an imperforate terminal end. There were no other abnormalities. The patient underwent marsupialization of the left imperforate submandibular duct with a ductoplasty consisting of tacking the everted edges of the duct to the floor of mouth with small absorbable sutures. Free flow of saliva was obtained. The patient has done well with no evidence of restenosis or obstruction of her left submandibular duct in several months of follow-up.
Case 5
A one-week-old white male was noted to have a slowly enlarging cyst-like lesion in the left floor of mouth. Needle decompression was initially performed with removal of 3 ml of seromucinous fluid. One week later, the cyst had recurred and was impairing the infant’s ability to feed. A magnetic resonance imaging scan was obtained which revealed increased signal intensity extending from the left submandibular gland to the floor of mouth (Fig. 4). One week later, this lesion was
Fig. 4. Case 5: magnetic
resonance
imaging revealing fluid filled accessory gland located anteriorly.
duct with displaced
normal
I67
excised and the surgical findings revealed a cyst extending to the submandibular gland which was separate from the true submandibular duct. Pathologic diagnosis was a benign epithelial cyst lined with non-ciliated stratified columnar epithelium, consistent with a ductal structure. The postoperative course has been uneventful without evidence of recurrence in over one year.
Discussion
The submandibular gland arises from proliferation and ingrowth of ectodermal cells in the oral cavity beginning at about the 10th to the 12th gestational week [41. Further differentiation takes place with development of the acinar complexes and the ductal system until full term. One of the last processes to occur in development is the hollowing of the epithelial tissue to allow for a patent ductal system. If this hollowing fails to occur at the terminal aspect of the duct, imperforation of Wharton’s duct occurs allowing for the development of these described floor of mouth lesions. Also, if the developing duct were to invaginate in two places, or if premature ventral branching of the duct were to occur, duplication anomalies of the duct and gland would be seen [6]. This is believed to be the etiologic factor in our last reported case. A ranula is broadly defined as a cystic tumor of the tongue or floor of mouth. It can be a fluid-filled mass associated with the obstruction of a minor salivary gland, or due to obstruction of the submandibular duct [2]. In the minor salivary gland associated lesion, the wall of the cyst consists of fibrous connective tissue and granulation tissue due to the escape of saliva into the surrounding tissue. With this lesion, simple incision leads to a high degree recurrence and the lesion must be excised. Conversely, the floor of mouth lesion that arises from obstruction of the duct is not connective tissue lined, but is lined by the epithelium of the ductal system. In this setting, simple marsupialization usually is satisfactory treatment and excision is not required. Patients with congenital submandibular duct obstruction must be treated in a timely fashion to prevent progressive dilation of the duct with ranula formation. Potential exists for infection of static saliva in the duct with sialoadenitis requiring incision and drainage and antibiotic therapy. Early marsupialization and ductoplasty can prevent these complications. To date, eight cases of imperforate submandibular ducts have reported. All of the cases have responded with a form of marsupialization with or without ductoplasty. This lesion may be more common than reported, as simple marsupialization seems adequate treatment. Additionally, some of these imperforate ducts may resolve spontaneously if rupture takes place with the trauma associated with sucking. Stenting of the ducts as done by Foretich [5] probably is not necessary if effective ductoplasty is performed to prevent stenosis. Also, stenting may be detrimental if stenosis results from the use of stents in the proximal ductal system. Although, these lesions may respond well to simple incision alone, we recommend marsupialization as adequate treatment. Ductoplasty may be beneficial in maintaining long-term patency.
168
Our last case represents a duplication anomaly of the submandibular duct with obstruction of the accessory duct and gland with ranula formation. A displaced, but present, submandibular gland was noted on the magnetic resonance imaging scan and the patency of the normal duct was confirmed in the operating room. MRI scanning clearly visualized the abnormal duplicated duct, and seems valuable in the diagnosis of these lesions. We have no experience with CT scanning in these lesions. As MRI scanning is done without radiation, it seems a safe and cost-effective radiologic diagnostic procedure when a physician is faced with floor of mouth lesions such as this. The lining of this cystic structure was ductal tissue confirming that this lesion was in fact an obstructed accessory duct. In our case, excision of the duplicated duct and gland was curative. Since most previously reported cases of duplication anomalies of the submandibular duct system have been in asymptomatic patients, treatment must be individualized to the pathologic process to which the duct is involved.
Conclusion This report describes one bilateral case and three unilateral cases of imperforate submandibular ducts. The bilateral case and one unilateral case were successfully treated with marsupialization and ductoplasty. Two of the unilateral cases responded to simple incision of the fluid-filled duct. This lesion is presumed due to incomplete cannulization of the terminal end of the duct. Only eight cases of this lesion have previously been reported and each responded with some form of marsupialization. This lesion may actually be more common than suggested by review of the literature, as simple incision to establish patency can be curative. Patients with imperforate submandibular ducts should be treated with early marsupialization to assure patency of the duct and prevent further complications such as ranula formation or sialoadenitis. Ductoplasty may be helpful in assuring long-term patency, but it is not clear if this procedure is helpful because of the small number of cases reported and short-term follow up. Ductoplasty would seem to add little morbidity to the procedure, and should be considered on an individual case basis. The last case is a previously unreported lesion in a newborn consisting of a duplication anomaly of the submandibular duct with cystic dilation and ranula formation. These lesions are best treated with complete excision of the cystic duplication lesion and careful preservation of the submandibular duct.
References 1 Addante, R.R., Congenital cystic dilation of the submandibular duct, Oral Surg., 59 (1984) 656-658. 2 Cummmings, C.W. et al., Otolaryngology-Head and Neck Surgery, C.V. Mosby, St. Louis, 1986, p. 1440. 3 Dore, P. and Dozin, A., False ranula of the newborn or imperforation of Wharton’s duct, Rev. Stomatol. (Paris), 69 (1968) 219-226.
IhY
4 El-Mohandes, E.A. et al., Prenatal development of the human submandibular gland. Acta Anat. I30 (1987) 213-218. 5 Foretich. E.A. et al., Bilateral congenital absence of the submandibular duct orifices.. J. Oral Surp.. 31 (1973) 556-557. 6 Jafek, B.W. and Strifo, J.L., Accessory lobe of the submandibular glands. Radiology, 109 tIY7il 75-77. 7 Mori. S. et al., Accessory duct in the submandibular gland. Oral Surg. Oral Med. Oral Pathol. 62 (19%) 607-608. X Myenson. M. et al., Bilateral duplication of the suhmandihular ducts. Arch. Otolaryngol.. 83 ( IYhh) 488-490. Y Rahmothulla, M., A rare case of accessory duct in submandibular sialography. J. Ind. Dental Assoc.. 4s (1973) 563-564. 10 Redpath. T.H., Congenital ranula, Oral Surg., 31 (lY73) 446-557. 11 Rose, Ben-Henry, Bifunction of the submaxillary duct, Am. J. Surg. I7 (1932) 257-258. 12 Scher, L.B. and Scher. I., Case of imperforate submandibular ducts in an infant. Br. Dent. _I.. YX (1955) 324. 13 Towers. J.F., Duplication of the submandibular salivary duct. Oral Surg. Oral Med. Oral Pathol.. 44 (1977) 320.