Microsurgical anatomy of the internal carotid artery at the skull base.

BACKGROUND: The aetiology and significance of internal carotid artery variations at the skull base remain controversial after decades, with limited available literature. Approximately 10-40 per cent of the general population has parapharyngeal internal carotid artery variations. METHOD: A prospective observational study was conducted on internal carotid artery variations in 36 cadavers, in a tertiary care hospital, between March 2019 to March 2020. RESULTS: The most common internal carotid artery variation observed in the specimens was tortuosity, in 30 per cent, followed by kinking in 18 per cent and coiling in 10 per cent. Thirty per cent of specimens had variations present bilaterally. A loop pattern of the internal carotid artery was identified. Coiling of the internal carotid artery may present as a node; hence, meticulous dissection is advocated near the skull base to avoid complications. These variations hold utmost importance for otorhinolaryngologists performing pharyngeal and nasopharyngeal surgical procedures. CONCLUSION: A detailed knowledge of anatomy, along with its variations, and surgical expertise, will help reduce the incidence of surgical complications.

Labyrinthine Fistula-Our Experience at a Tertiary Hospital.

This study has aimed to determine the anatomical site of labyrinthine fistula in patients of chronic suppurative otitis media at our centre. Labyrinthine fistulae (LF) are caused by abnormal communications between the inner ear and surrounding structures resulting in perilymph leakage and hearing loss. Labyrinthine fistula represents as erosive loss of the enchondral bone overlying the semicircular canals without loss of perilymph. The manifestations of fistula like vertigo, hearing loss vary in severity and complexity, commonly ranging from very mild to incapacitating. Cholesteatoma induced fistula most commonly involves lateral semicircular canal probably because of its close proximity to the middle ear, but can involve other semicircular canals and rarely cochlea. This is a retrospective analysis of 36 patients of chronic suppurative otitis media with history of vertigo undergoing tympanomastoid surgery in whom there was an evidence of labyrinthine fistula on HRCT scan of temporal bone. The incidence of patients with labyrinthine fistula presenting with vertigo, nystagmus, sensorineural hearing loss, history of vertigo were analysed. The anatomical location of the fistula was supported by Radiological evidence. Patients underwent either canal wall down mastoidectomy or cortical mastoidectomy. The anatomical site and length of the labyrinthine fistula were analysed. Amongst the 36 patients of chronic suppurative otitis media with labyrinthine fistula 22 (61.1%) patients had atticoantral disease, 4 (11.1%) patients had chronic otitis media with extensive granulation, 2 (5.5%) patients had Tubotympanic disease with polyps, 4 (11.1%) patients had Tuberculous otitis media, 1 (2.77%) patient had Tubotympanic disease with extensive tympanosclerosis eroding the dome of lateral semicircular canal, 1 (2.77%) patient had extensive cholesteatoma with cerebellar abscess, 1 (2.77%) patient had fistula in the promontory following trauma, 1 (2.77%) patient had extensive tympanosclerosis with erosion of promontory. It was noticed that, in 14 (38.88%) patients the fistula was at the centre, in 17 (47.22%) patients the fistula is towards the ampullary end of horizontal semicircular canal and in 5 (13.88%) patients the fistula was towards the non ampullary end of lateral semicircular canal. The maximum length of fistula noticed was 6 mm and the minimum length of the fistula noticed was 2 mm. Labyrinthine fistula are most commonly noticed in the ampullary end of the lateral semicircular canal. The average length of the fistula was found to be 4 mm. Careful elevation of the cholesteatoma matrix over the endosteal membrane and immediate placement of temporal fascia over the exposed fistula is important to avoid injury to the inner ear. Maximum number of fistula were seen in the atticoantral type of Chronic suppurative otitis media. Prior knowledge of anatomical location of the fistulous tract in HRCT temporal bone is important to address the fistula.

Comparision of Allogenic Cartilage and Autologous Cortical Bone in Ossicular Reconstruction: A Comparative Study.

Ossicular discontinuity is the most common cause of conductive hearing loss. The use of ossicular graft material in ossicular chain reconstruction significantly improves the result in hearing. This study was conducted to compare and analyze the outcome of ossicular reconstruction using allogenic septal spur cartilage and autologous cortical bone in terms of hearing results and graft uptake rates. Study design: randomized clinical trial. Study included 112 patients visiting our ENT department. Patients between 16 and 50 years of age with history of chronic ear discharge and air-bone-gap (ABG) of > 35 dB and ossicular involvement were included in the study. The patients underwent detailed ENT examination, audiological and radiological assessment of temporal bone and those patients with evidence of ossicular erosion were subjected to ossiculoplasty with allogenic septal spur cartilage (group I) and autologous cortical bone (group II) randomly. The patients were followed up to 6 months to analyze functional and anatomical results. 50 patients out of 56 patients (90%) from group I who underwent allogenic septal cartilage ossicular reconstruction showed significant improvement in hearing as assessed by pure tone audiogram after 3 months and 6 months. Remaining 10% of patients who did not show hearing improvement on PTA were reopened after 6 months. It was observed that the stapes head got necrosed in them. 40 patients (72%) out of 56 patients (50%) from group II who underwent autologous cortical bone reconstruction showed hearing improvement. Remaining 16 patients (28%) showed no hearing improvement. They were reopened and ankylosis, dislocation of ossicle and extrusion were noted. In our study, graft uptake rates, formation of retraction pockets, and hearing improvements were analyzed. Complications like ankylosis formation, dislocation of ossicle and extrusion rates were more in the group II compared to group I. Hearing results of group I are better compared to group II and the allogenic septal cartilage being readily available is a good option for ossicular reconstruction.

Extensive Cholesteatomas: Presentation, Complications and Management Strategy.

To document the clinical presentation, complications, management strategy and post-operative outcomes of extensive cholesteatomas. Cholesteatoma is a well demarcated cystic lesion derived from an abnormal growth of keratinizing squamous epithelium in the temporal bone. Cholesteatomas commonly involve the middle ear, epitympanum, mastoid antrum and air cells and can remain within these confines for a considerable period. Bony erosion is present confined to ossicular chain and scutum initially, but as the cholesteatoma expands, erosion of the otic capsule, fallopian canal and tegmen can occur. Erosion of the tegmen tymapani or tegmen mastoideum may lead to development of a brain hernia or cerebrospinal fluid leakage. Invasion of jugular bulb, sigmoid sinus, internal carotid artery are noticed in extensive cholesteatoma and are quite challenging and requires expertise. Neurosurgical intervention should be considered along with the otological management in the same sitting in all possible cases. A retrospective review of 12 patients were carried out to assess the clinical presentation, complications, surgical management and postoperative outcomes of extensive cholesteatomas presenting at our centre between January 2017 and December 2019. CT or MRI findings, extent of cholesteatoma intra-operatively along with the status of major neurovascular structures and disease clearance, and the post-operative outcomes including morbidity and mortality were noted. All patients underwent canal wall down mastoidectomy with or without ossiculoplasty. Post operatively all patients were treated with intravenous antibiotics and if required intravenous steroids. Amongst the 12 patients of extensive cholesteatoma (EC), all of them (100%) presented with foul smelling, purulent ear discharge. 9 (75%) patients presented with otalgia. 4 (33.33%) patients had temporal headache. 10 (83.33%) patients complained of hard of hearing. 7 (58.33%) patients gives history of vertigo at the time of presentation. In 8 (66.66%) patients there was tegmen plate erosion noticed in CT scan. In 3 (25%) patients, the disease was invading the sigmoid sinus and in 1 (8.33%) patient jugular bulb was involved. In 3 (25%) cases of EC, blind sac closure was performed. In two patients who developed cerebellar abscess, drainage procedure was performed. 2 (16.66%) patients developed sigmoid sinus thrombosis, 1 (8.33%) patient had petrositis.

Outcome of Submucosal Inferior Turbinoplasty in Perennial Allergic Rhinitis.

Pharmacotherapy forms mainstay of treatment for allergic rhinitis, and has adverse effects associated with it. Topical steroid therapy is the preferred medication and considered best for long term prophylaxis but with limited compliance. Submucosal turbinoplasty reduces the duration of treatment in comparison to topical steroid which has to be taken daily for a long time. The aim was to evaluate the outcome of submucosal inferior turbinoplasty in patients with perennial allergic rhinitis. A prospective interventional study was performed on 35 patients diagnosed with perennial allergic rhinitis, diagnosed as per ARIA criteria from July 2016 to July 2018. The severity of the disease was assessed using mini RQLQ scoring system. The patients were then subjected to bilateral submucosal inferior turbinoplasty under endoscopic guidance under local anesthesia. 50% significant improvement (p value < 0.05) seen in symptoms were need to blow nose, sneezing, nasal obstruction, nasal discharge, watery eyes, need to rub eye, regular house work, recreational activities, sore eyes, tiredness, irritability and thirst. 100% improvement (p value < 0.05) seen in symptoms were sleep, need to blow nose, sneezing, nasal discharge, watery eyes, need to rub eye, recreational activities and irritability. Nasal obstruction was not severe in 17 (48.5%) patients giving a very good symptom relief and improving quality of life. This is due to reduction in the erectile tissue and roominess in the nasal cavity. All patients with allergic rhinitis with associated hypertrophied turbinates should invariably be given option of inferior turbinoplasty along with proper counselling regarding its advantages and disadvantages.

Fronto Ethmoidal Mucocele Associated with Type 4 Kuhn Cells.

A mucocele is an epithelial lined mucous containing sac completely filling the sinus and capable of expansion. We report a case with unilateral frontoethmoidal mucocele in relation with type IV Kuhn cell. A 26 year old man came to the ENT department at SDUMC, Tamaka, Kolar, presenting complaints of proptosis of left eye since 3 years. After detailed examination and investigations patient was Diagnosed to have mucocele of left frontoethmoidal region. Intraoperatively we found a rare picture of type IV kuhn cells completely seated in the frontal sinus. After externally assisted modified Lothrop's approach, marsupialization of mucocele was done in the nasal cavity and symptoms of the patient relieved. We state that, in cases of frontoethmoidal mucocele, externally assisted modified Lothrop procedure offers an alternative for endoscopic management of frontoethmoidal mucocele for the complete clearance of disease.

Microsurgical Anatomy of Stapedius Muscle: Anatomy Revisited, Redefined with Potential Impact in Surgeries.

Stapedius muscle even though being the smallest skeletal muscle in human body, it has a major role in otology. As many of the distinguished books in otology missed to explain much about stapedius muscle, and also considering the need for the anatomy based visit to this small muscle we felt it was important to have a exercise like this. In the dissection hall of our institution we dissected 32 cadaveric temporal bones and delineated stapedius muscle as a part of PG teaching programme to have a clear idea of the anatomy of stapedius muscle, its origin, attachment, extension, size (all dimensions). Length of the stapedius muscle varied between 9 and 11 mm. Stapedial tendon measured about 2 mm. The muscle had a classical sickle shape with tendon looking like the handle of the sickle. It has a bulky belly with a maximum breadth of 2-3 mm. It was found to be medial to midportion of vertical limb of facial nerve. All of our temporal bones measured size varied from 9 to 11 mm in length excluding stapedial tendon. Stapedial tendon measured almost 2 mm. Muscle is classical sickle shaped with tendon acting like the handle of the sickle. It has a bulky tummy which forms the maximum breadth of 1-3 mm. Why to have a clear idea about the anatomy of stapedius muscle is that, unless the anatomy is clear there is chance of confusing the muscle with that of facial nerve while doing facial nerve grafting and also while drilling for facial nerve decompression in experienced hands may get confused and decompress the muscle. Stapedius muscle said to be the smallest muscle in the body, but its not as small as its been described. Detailed awareness of the anatomy of stapedius muscle is needed so as to avoid confusion while facial nerve grafting and while drilling.

Stapes Surgery Teaching Tool: A Simple and Stable Technique.

Stapedotomy followed by placement of a piston prosthesis is the mainstay for surgical management of otosclerosis primarily undertaken to improve hearing in patients. Although a simple and elegant procedure, prosthesis placement in stapes surgery is difficult to master. Improper surgical technique or improper placement of prosthesis may result in complications which may require revision surgery. We here describe a training technique that is simple, inexpensive, improves the skills and can be done using easily available materials such as a disposable syringe, stapler pin and micro-forceps. Regular practice with this training module minimizes surgical time and can even be done just prior to the surgery, however, this is not a substitute for temporal bone dissections.