DOI: 10.18410/jebmh/2015/652
CASE REPORT
AN UNCOMMON PRESENTATION OF PRE-AURICULAR SINUS
Anoop M1, Asra Tamkanath2, Tasneem Fatima3, Omer Bin Jabri4, Gurbeer Kaur5
HOW TO CITE THIS ARTICLE:
Anoop M, Asra Tamkanath, Tasneem Fatima, Omer Bin Jabri, Gurbeer Kaur. ”An Uncommon Presentation
of Pre-Auricular Sinus”. Journal of Evidence based Medicine and Healthcare; Volume 2, Issue 31,
August 03, 2015; Page: 4645-4649, DOI: 10.18410/jebmh/2015/652
ABSTRACT: Many times pre-auricular sinus may present as ‘variant type’ in the post-auricular
region. Here we present 19 year old female who used to get recurrent swelling associated with
discharge in the post-auricular region since childhood. We identified a small discharging pit in the
right post-auricular region just at the lower aspect of retro-auricular groove. X-ray sinogram
confirmed the tract to be of 1.9cm and communicate with external auditory canal. The entire
sinus tract was excised under microscopic guidance via post-auricular approach. The patient was
followed regularly for one year and there was no further recurrence in the form of either
discharge or swelling. Awareness regarding the ‘variant type’ of pre-auricular is essential to avoid
unnecessary investigations and surgical procedures which may subsequently impact the outcome
of surgical excision and reduce the risk of complications.
KEYWORDS: Sinus, Excision, Sinogram.
INTRODUCTION: Pre-Auricular sinus is a common clinical entity in the ENT Surgeons practice
all across the globe. Mostly it present in front of the auricle without any diagnostic confusion. But
variance does occur in its presentation. It gets significance when present as an abscess either in
normal or its variant sites. If we do incision and drainage as for a conventional abscess, the
patient may not be benefitted. The tract of sinus may get obliterated and recurrence of the
condition is the net result. Add to it, treatment of recurrent condition is more demanding and
difficult. So awareness regarding pre auricular sinus and its variable presentations is useful for
any practicing ENT surgeon
CASE REPORT: We present a case of a 19 years old female who presented with discharge
behind the right ear associated with post-auricular swelling since childhood. When she took
antibiotics and supportive medicines, the discharge and swelling subsided but to recur when she
gets upper respiratory tract infections. There was no otorrhoea or hearing loss. On careful
examination, a sinus was noted at the right post-auricular region, just at the lower aspect of retro
auricular groove. Examination of external auditory canal (EAC) and Tympanic Membrane were
normal. No other pits were found around the auricular region of the opposite ear.
The patient was treated with a course of Antibiotics. X-Ray sinogram was done and sinus
tract seen to extend for a length of 1.9 cm and seen to communicate with extend auditory
meatus (Fig. 1). The sinus tract was completely excised under general anaesthesia by Post
auricular approach. The entire sinus tract was excised from the inferior aspect of retro auricular
groove up to floor of external auricular canal, were the interior opening of sinus was seen. The
excised specimen was sent for histopathological Examination (Fig. 2 and 3). After 3 weeks the
meatal pack was removed and there was no narrowing of EAC or granulation at the operated site.
J of Evidence Based Med & Hlthcare, pISSN- 2349-2562, eISSN- 2349-2570/ Vol. 2/Issue 31/Aug. 03, 2015 Page 4645
DOI: 10.18410/jebmh/2015/652
CASE REPORT
The patient was followed up regularly for 1 year and there was no further swelling or discharge at
the operated site.
DISCUSSION: The condition was first described by Van Heusinger in 1864. In most preauricular sinuses, the sac is located anterior to the external auditory canal and is rarely posterior
to it. This rare type of Pre-auricular sinus with its sac posterior to the EAC has previously has
been described as a ‘variant type’(2) of pre-auricular sinus (Post-auricular Sinus) as compared to
the classical type which has its sac anterior. A retrospective study with 101 Patients who
underwent pre-auricular sinus excision found that about 10% of the pre-auricular sinus was of
the ‘variant type’. All ‘Variant Type’ of pre-auricular sinus also showed auricular pits located
posterior to the imaginary line that connects the tragus with the posterior margin of ascending
limb (Fig. 4). This finding was consistent with auricular pit found in our patient. This highlights
the importance of careful examination of the external ear in patients who present with an
infected post auricular cyst as these patients are often misdiagnosed as infected dermoid or
sebaceous cyst. A sub-periosteal abscess complicating as acute mastoiditis may also present with
a post auricular infected swelling although there will usually be other accompanying auditory
symptoms such decreased hearing or otorrhoea on the affected side.
An accurate and correct diagnosis will also aid in the appropriate management of these
patients. The most problematic complication after surgical excision is the recurrence due to
incomplete excision of sinus tract. Incision and drainage of an infected post auricular cyst(1) often
results in anatomical disruption of the sinus tracts complicating future surgical excision, resulting
in increased risk of recurrence.
Synonyms for pre-auricular sinus are pre-auricular pit, pre-auricular fistula, pre-auricular
tract, helical fistula, pre-auricular cyst.
Incidence rate as per US study is 0.1 – 0.9%. Studies in Africa Put a slightly higher figure
of 4-5%.
Mode of inheritance is either sporadically or may be inherited. In about half the number of
patients it occurs in a sporadic manner and commonly on the right side. Bilateral cases are
commonly genetically inherited. Studies have shown that inheritance is autosomal dominant with
varying degree of penetration (about 85% penetration).Studies in China has shown chromosome
8q11 to be the site of abnormal gene which transmits pre-auricular sinus pre-auricular sinus has
been described as a part of number of syndromes. These include BOR syndrome,
Branchiootourethral syndrome, Branchiootic syndrome, Branchiootocostal syndrome, Cat eye
syndrome, Trisomy22. Clinical feature wise pre-auricular Sinus is seen as a small pit usually in the
anterior margin of the ascending limb of the helix. In some patients this opening may also see
along the posterosuperior margin of helix. The Sinus Tract may follow a tortuous course. The
sinus tract is usually superior and lateral to the facial nerve and parotid gland. This feature
differentiates it from branchial cleft anomalies. Sometimes the pre-auricular sinus may lead to the
formation of subcutaneous cyst that is intimately related to tragal cartilage and the crus of helix.
Patients usually present with discharge from the pre auricular sinus pit. Discharge could be due to
desquamating epithelial debris or infection. Common pathogens causing infection in the
preauricular sinus include staphylococcus, proteus, streptococus and peptococus. It is always
J of Evidence Based Med & Hlthcare, pISSN- 2349-2562, eISSN- 2349-2570/ Vol. 2/Issue 31/Aug. 03, 2015 Page 4646
DOI: 10.18410/jebmh/2015/652
CASE REPORT
better to rule out syndromes associated with pre-auricular sinus. Almost majority of these
syndromes involve kidney.
Wang et al, of California came out with a set of indications, when ultrasound abdomen
should be performed in these patients with Pre-auricular sinus.
1. Presence of another malformation/dysmorphic feature.
2. Family history of deafness.
3. Malformation involving pinna.
4. Maternal history of gestational diabetes.
Common sites of pre-auricular sinus involvement are:
1. Anterior margin of ascending limb of helix (most common).
2. Superior to auricle.
3. Along the posterior surface Cymba Concha.
4. Lobule.
- Posterior to auricle.
While surgically excising the sinus tract care should be taken to completely remove it.
Incomplete removal of sinus tract is the commonest cause for recurrence. The recurrence rate
ranges between 1 to 45% depending on the procedure followed.
Causes of Recurrence:
a. Major cause of recurrence is inadequate removal of the mass.
b. Performing the surgery without magnification Aids.
c. Skill of the operating surgeon. This is rather important because surgeons.
Consider this case to be a minor procedure and hence pass it on either to novice or junior
surgeon who may not be experienced enough in performing this type of surgery.
Supra Auricular Approach is a radical approach. Major advantage of this approach is that it
gives excellent exposure and hence removal of the sinus tract is nearly complete. This procedure
has the lowest recurrence rate among all other surgical procedures for pre auricular sinus
removal.
This procedure involves a post auricular extension of the elliptical incision around the
Preauricular sinus opening.(3) The incision is deepened till the temporalis fascia comes into view.
This is supposedly the medial limit for resection in this procedure. All the tissue superficial to the
temporalis fascia is removed together with the preauricular sinus. A portion of the cartilage along
the base of the preauricular sinus should also be excised. The dead space should be closed in
layers and compression dressing should be applied. A drain need not be placed here.
CONCLUSION: Preauricular Sinus may present as its “variant” in post auricular region. So when
a patient present with swelling and discharge in the post auricular region the diagnostic possibility
of “variant” type of Preauricular Sinus should be considered. This helps to avoid unwanted
investigations and interventions which may only serve to complicate future management of these
patients.
J of Evidence Based Med & Hlthcare, pISSN- 2349-2562, eISSN- 2349-2570/ Vol. 2/Issue 31/Aug. 03, 2015 Page 4647
DOI: 10.18410/jebmh/2015/652
CASE REPORT
REFERENCES:
1. Chang PH, Wu CM. An insidious Preauricular Sinus presenting as an infected post auricular
cyst.Int J Clin Pract.2005; 59(3): 370-2.
2. Choi SJ, Choung YH, Park K, et al. The variant type of Preauricular Sinus: postauricular
sinus.Laryngoscope.2007; 117(10): 1798-802.
3. Coatesworth AP, Patmore H, Jose J. Management of an infected Preauricular Sinus, using a
lacrimal probe. J Laryngol Otol. 2003; 117(12): 983-4.
Fig. 1: Sinogram of pre
auricular sinus
Fig. 3: Excision of pre
auricular sinus
Fig. 2: Sinus pit
Fig. 4: Common sites
of pre auricular sinus
J of Evidence Based Med & Hlthcare, pISSN- 2349-2562, eISSN- 2349-2570/ Vol. 2/Issue 31/Aug. 03, 2015 Page 4648
DOI: 10.18410/jebmh/2015/652
CASE REPORT
AUTHORS:
1. Anoop M.
2. Asra Tamkanath
3. Tasneem Fatima
4. Omer Bin Jabri
5. Gurbeer Kaur
PARTICULARS OF CONTRIBUTORS:
1. Assistant Professor, Department of ENT,
Shadan Institute of Medical Sciences,
Teaching Hospital & Research Centre.
2. Assistant Professor, Department of ENT,
Shadan Institute of Medical Sciences,
Teaching Hospital & Research Centre.
3. Senior Resident, Department of ENT,
Shadan Institute of Medical Sciences,
Teaching Hospital & Research Centre.
4. Junior Resident, Department of ENT,
Shadan Institute of Medical Sciences,
Teaching Hospital & Research Centre.
5. Junior Resident, Department of ENT,
Shadan Institute of Medical Sciences,
Teaching Hospital & Research Centre.
NAME ADDRESS EMAIL ID OF THE
CORRESPONDING AUTHOR:
Dr. Anoop M,
Assistant Professor,
Department of ENT,
Shadan Institute of Medical Sciences,
Teaching Hospital & Research Centre,
Himayathsagar Road,
Hyderabad-500008, Telangana.
E-mail: dranoopavittom@gmail.com
Date
Date
Date
Date
of
of
of
of
Submission: 13/07/2015.
Peer Review: 14/07/2015.
Acceptance: 27/07/2015.
Publishing: 01/08/2015.
J of Evidence Based Med & Hlthcare, pISSN- 2349-2562, eISSN- 2349-2570/ Vol. 2/Issue 31/Aug. 03, 2015 Page 4649