Lateral Bulla Osteotomy Research Articles

Comparative study on total ear canal ablation and lateral bulla osteotomy in dog

Comparative study on total ear canal ablation and lateral bulla osteotomy in dog

External auditory canal atresia affecting the horizontal canal of a 2‐year‐old Labrador Retriever dog

AbstractA 2‐year‐old, female neutered, Labrador Retriever dog was presented with left otalgia. Otoscopic examination revealed a blind ending left external ear canal. Magnetic resonance imaging confirmed an abrupt narrowing of the lateral aspect of the horizontal canal, medial to which the remaining horizontal ear canal and middle ear cavities contained well‐delineated, homogenous, T2w, fluid‐attenuated inversion recovery and T1w hyperintense, non‐contrast enhancing material. A diagnosis of external auditory canal atresia was made based on the imaging findings. Considering the patient's age and absence of preceding trauma, a congenital cause was considered most likely. Surgical treatment by way of a total ear canal ablation with lateral bulla osteotomy was performed. At the re‐check appointment, the surgical site had healed well and there were no associated complications noted; a telephone call with the owner 5 months later documented no clinical concerns.

Total ear canal ablation and lateral bulla osteotomy (TECA/LBO) for the management of ear canal tumor in an Amarican Bull dog

Total ear canal ablation and lateral bulla osteotomy (TECA/LBO) for the management of ear canal tumor in an Amarican Bull dog

Congenital aural atresia in a 4‐month‐old Dalmatian

AbstractA 4‐month‐old female entire Dalmatian was presented for persistently excessive ceruminous discharge, suspected left aural malformation and decreased hearing. Otoscopic examination of the left ear showed a normal external meatus with an abnormal ending of the ear canal in a cul‐de‐sac. Computed tomography (CT) study of the head showed a diffusely tortuous and convoluted external ear canal with saccular distension and a stenotic area with the presence of a septum. Based on the clinical presentation and imaging findings, total ear canal ablation and lateral bulla osteotomy were performed. Macroscopically, the ear canal appeared to be sigmoid, as in the CT study. Notably, in the stenotic area, there was a membrane separating the vertical and horizontal ear canals. The histopathology of the external ear canal was consistent with that of hyperplastic otitis externa. No growth was observed on bacterial culture. The dog recovered uneventfully and no abnormalities were detected on re‐examination 2 weeks post‐surgery.

Evaluation of endoscopic-assisted feline lateral bulla osteotomy: a cadaveric study.

The aims of the study were to investigate if feline middle ear anatomy can be visualized using endoscopy via a lateral bulla approach and to determine if scope-assistance increases rates of successful entry into the hypotympanum during feline total ear canal ablation and lateral bulla osteotomy (TECA-LBO). A total of 13 feline cadaver heads underwent CT to confirm the absence of pre-existing middle ear disease. For each head, an electronic coin toss was used to determine which ear would undergo endoscope-assisted TECA-LBO; a traditional TECA-LBO without the use of the scope was performed on the contralateral side. In endoscope-assisted procedures, a 1.9 mm scope was intermittently inserted into the tympanic bulla via a lateral bulla approach and used to identify middle ear structures, visualize the bony septum and confirm entry into the hypotympanum. After the bilateral TECA-LBO, the cadaver heads were imaged again and assessed for evidence of entry through the septum. Soft tissue and osseus structures of the middle ear were readily visualized with a 1.9 mm scope. Success rates for entry into the hypotympanum were high between both endoscope-assisted and traditional procedures, with entry confirmed for 12/13 ears in each group. Endoscope assistance can facilitate the identification and examination of middle ear structures but does not appear to increase the success rate of entry into the hypotympanum during feline TECA-LBO, as entry through the bony septum was consistently accomplished even without scope-assisted visualization. Alternative benefits to scope assistance may exist, and future studies to elucidate its impact on rates of intraoperative trauma to middle ear structures are indicated.

Influence of extreme brachycephalic conformation on perioperative complications associated with total ear canal ablation and lateral bulla osteotomy in 242 dogs (2010-2020).

To determine the influence of extreme brachycephalic conformation on presenting signs, imaging findings, intraoperative and perioperative complications following total ear canal ablation and lateral bulla osteotomy (TECA-LBO). Cross-sectional retrospective study. A total of 306 (n = 242 dogs) TECA-LBOs (extreme brachycephalic breeds [EBB] = 81, other breeds [OB] = 225). Medical records of patients undergoing TECA-LBO at a single referral institution (2010-2022) were evaluated. Extreme brachycephalic breeds most commonly presented acutely, at a younger age with oto-neurological signs (46/81, 56.8%). Chronic otitis externa without neurological signs (171/225, 76.0%) was most common in OBs. Extreme brachycephalic breeds preoperatively presented more frequently with facial nerve paresis (p = .001), vestibular syndrome (p = .001), and Horner's syndrome (p = .002) compared to OBs. On diagnostic imaging, bilateral changes (p = .038), aural masses (p = .045), para-aural abscesses (p = .011), otitis interna (p = .001), and brainstem changes (p = .001) were more common in EBBs. The apparent difference in intraoperative complication rate between EBBs (9/81, 11.1%) and OBs (12/225, 5.3%) did not reach statistical significance (p = .078). Perioperative complications occurred in 85/306 (27.8%) of TECA-LBOs with no difference in perioperative complication rate between EBBs (19/81, 23.5%) and OBs (66/225, 29.3%) (p = .586). Extreme brachycephalic breeds are more likely to present for TECA-LBO acutely, with neurological signs and more advanced diagnostic imaging abnormalities. Intra- and perioperative complication rates did not differ between EBBs and OBs. Despite being subjectively more technically challenging, TECA-LBO did not result in more surgical complications in EBBs. Reported data are useful for effectively informing clients of the specific risks of TECA-LBO surgery.

The Middle Ear Microbiota in Healthy Dogs Is Similar to That of the External Ear Canal.

Otitis media can be a consequence of chronic otitis externa and could represent a perpetuating factor. While the microbiota of the EEC in healthy dogs and in the presence of otitis externa has been described, only sparse information is available concerning the normal microbiota of the middle ear. The objective was to compare the tympanic bulla (TB) with the external ear canal (EEC) microbiota in healthy dogs. Six healthy experimental Beagle dogs were selected based on the absence of otitis externa, negative cytology and bacterial culture from the TB. Samples from the EEC and TB were collected directly after death using a total ear canal ablation and lateral bulla osteotomy. The hypervariable segment V1-V3 of the 16S rDNA was amplified and sequenced with a MiSeq Illumina. The sequences were analyzed by the Mothur software using the SILVA database. No significant differences between the EEC and TB microbiota for the Chao1 richness index (p = 0.6544), the Simpson evenness index (p = 0.4328) and the reciprocal Simpson alpha diversity (p = 0.4313) were noted (Kruskal-Wallis test). A significant difference (p = 0.009) for the Chao1 richness index between the right and left EEC was observed. The microbiota profile was similar in the EEC and the TB of the Beagles.

Perioperative complications and outcomes following partial ear canal ablation and lateral bulla osteotomy in pet rabbits: 20 cases (2009-2021).

To investigate the perioperative complications and outcomes of rabbits undergoing partial ear canal ablation and lateral bulla osteotomy for treatment of chronic otitis. Surgical logbooks were searched to identify rabbits that underwent partial earcanal ablation and lateral bulla osteotomy between December 2009 and September 2021. Datacollected included signalment, history, clinical signs, historical and current medical management,physical examination findings, preoperative diagnostic imaging and aural bacterial culture results, surgical procedure information, duration of hospitalisation, complications and final outcome. Twenty rabbits with chronic, medically unresponsive otitis underwent 27 partial ear canal ablation and lateral bulla osteotomies. Ten rabbits had pre-existing neurologic deficits and 17 had an ear base abscess at the time of surgery. A total of 13 (65%) rabbits developed at least one complication, either in the perioperative period or between discharge and recheck. Three of these rabbits (15%) underwent revision surgery for persistent or recurrent ear base abscess. Complete resolution of clinical signs ultimately occurred in 12 (60%) rabbits. Three (15%) rabbits showed improved but not completely resolved clinical signs (three facial asymmetry). Five (25%) rabbits died of causes potentially related to chronic otitis and/or partial ear canal ablation and lateral bulla osteotomy; two of these rabbits had undergone revision surgery. Although this study reports a high complication rate (65%), most complications resolved, with 15 (75%) rabbits having a good to excellent final outcome. Since the majority ofrabbits in this study had chronic and severe ear disease, further studies are required todetermineif surgical intervention earlier in the disease process could result in a lower complicationrate.

Clinical presentation, treatment, and outcome of 24 dogs with bacterial meningitis or meningoencephalitis without empyema (2010-2020).

Bacterial meningitis (BM) and meningoencephalitis (BMEM) are associated with high case fatality rates and neurologic sequelae in people, but limited data exists on outcome in dogs. To report the clinicopathologic features, treatment and outcome of BM/BMEM in dogs, with a focus on clinical presentation, relapse and long-term neurological deficits. Twenty-four client-owned dogs diagnosed with BM/BMEM without empyema. Retrospective case series of dogs diagnosed with BM/BMEM from 5 veterinary referral hospitals between January 2010 and August 2020. Twenty-four dogs were included. Median duration of clinical signs was 2 days (range ≤24 hours to 30 days) and signs recorded included pyrexia (3) and cervical hyperesthesia (10). Neurological deficits were present in 18 dogs including altered mentation (12), ataxia (8), nonambulatory status (8), head tilt (8), and cranial nerve deficits (13). Intracellular bacteria were visualized on cerebrospinal fluid (CSF) analysis in 15/24 dogs, with positive CSF bacteriological culture in 8/21. Otitis media/interna (OMI) was diagnosed in 15/24 dogs, of which 6/15 dogs underwent total ear canal ablation and lateral bulla osteotomy. Twenty dogs survived to hospital discharge. Median duration of antibiotic administrations was 8 weeks (range, 2-16 weeks). Glucocorticoids were administered to 15 dogs. Median follow-up time was 92 days (range, 10-2233 days). Residual neurological deficits were reported in 9 dogs, with a single case of suspected relapse. Clinical signs were variable in dogs with BM/BMEM, the nidus of bacterial infection was often OMI and the majority of dogs made a full recovery with treatment.

Effect of empirical versus definitive antimicrobial selection on postoperative complications in dogs and cats undergoing total ear canal ablation with lateral bulla osteotomy: 120 cases (2009-2019).

To evaluate dogs and cats undergoing total ear canal ablation with lateral bulla osteotomy (TECA-LBO), document antimicrobial choices, and determine relationships associated with infection-related and neurologic postoperative complications. 107 client-owned dogs and 13 client-owned cats that underwent TECA-LBO. A retrospective analysis of medicals records of dogs and cats with TECA-LBO from 2 veterinary hospitals with postoperative data for at least 6 months was performed. All information associated with the TECA-LBO surgery including follow-up was recorded. Logistic regression analyses were performed and corrected using a false discovery rate to identify significance between antimicrobial administration and other perioperative variables and the outcomes of short- and long-term neurologic and infection-related complications, need for revision surgery, and euthanasia due to recurrence of infection-related signs. Intraoperative cultures were performed in 111 animals, and 95 (85.5%) had bacterial growth, with Staphylococcus spp most commonly isolated. Revision surgeries due to infection-related signs occurred in 13 of 120 (10.8%) patients. If intraoperative bacterial cultures were positive and antimicrobials were administered within 1 month of surgery, patients were 85.8% less likely to exhibit infection-related complications, whereas patients not administered antimicrobials were 10.3 times as likely to require a revision surgery. Longer durations of postoperative antimicrobial administration were associated with revision surgery and euthanasia due to infection-related signs. Administration of systemic antimicrobials within the first postoperative month may be necessary to prevent complications when intraoperative cultures exhibit bacterial growth and plays a role in the successful outcome of TECA-LBO.

TOTAL EAR CANAL ABLATION AND LATERAL BULLA OSTEOTOMY (TECA-LBO) IN ATLANTIC HARBOR SEALS (PHOCA VITULINA CONCOLOR) FOR SUCCESSFUL SURGICAL MANAGEMENT OF OTITIS MEDIA.

Chronic, severe otitis media was diagnosed in four Atlantic harbor seals (Phoca vitulina concolor), three of which were stranded animals undergoing rehabilitation. All seals presented with unilateral purulent aural discharge that would intermittently recur despite prolonged topical and systemic antimicrobial therapy. Aerobic culture from aural discharge isolated multidrug-resistant organisms in all seals, including Pseudomonas aeruginosa, Staphylococcus pseudintermedius, Klebsiella pneumoniae, and/or Enterococcus faecalis. Computed tomography was used in three cases to confirm otitis media and positive contrast ear canalography was used in one case to confirm tympanic membrane rupture. Given the persistent nature of otitis, surgical intervention in the form of a total ear canal ablation and lateral bulla osteotomy (TECA-LBO) was indicated. Surgery was successful in achieving complete clinical resolution of otitis in all seals. Postoperative complications included temporary unilateral paralysis of the left nare (2/4) and a transient left ptosis (1/4). Partial to complete surgical site dehiscence occurred in all cases; however, complete healing was achieved by second intention in 60 d or less. One rehabilitated seal was fitted with a satellite tag that confirmed normal swimming and diving patterns post release. In harbor seals, TECA-LBO can be performed safely to treat persistent cases of otitis media and should be considered in cases of chronic otitis that are not responsive to medical management.

Experience level as a predictor of entry into the hypotympanum during feline total ear canal ablation and lateral bulla osteotomy.

The study hypotheses were as follows: (1) owing to the unique anatomy of the feline middle ear, the hypotympanum would be entered in less than 100% of cats during total ear canal ablation and lateral bulla osteotomies (TECA-LBOs); and (2) incomplete penetration of the septum and subsequent failure to enter the hypotympanum is more likely to occur in surgeries performed by a novice surgeon when compared with an experienced surgeon and may be under-recognized. Head CT was performed in 12 feline cadavers to confirm absence of gross ear disease. A novice surgeon and an experienced surgeon were randomly assigned to perform TECA-LBO on the left or right ear. Surgeons were blinded to each other's surgical technique. CT of cadavers was performed after the procedure. Successful penetration of the septum, entry into the hypotympanic cavity and amount of bone removed in bulla osteotomy, quantified via CT, were compared between the novice surgeon and experienced surgeon. The novice surgeon entered the hypotympanum in 3/12 (25%) procedures, compared with 9/12 (75%) procedures performed by the experienced surgeon. The experienced surgeon performed a larger osteotomy than the novice surgeon (3301 mm vs 1376 mm, P <0.0023). Regardless of surgeon experience, more bone was removed in surgeries in which the hypotympanum was entered. Our results underscore the need for familiarity with feline middle ear anatomy when performing TECA-LBOs. Postoperative CT is recommended for novice surgeons to confirm entry into the hypotympanum.

Otoscopic evaluation of epithelial remnants in the tympanic cavity after total ear canal ablation and lateral bulla osteotomy.

To determine the ability to detect the presence of epithelial remnants after total ear canal ablation (TECA) and lateral bulla osteotomy (LBO) with endoscopy and to identify the most common locations of epithelial remnants after tympanic curettage. Experimental study. Five fresh canine cadavers with no gross evidence of middle ear disease. Ten TECA-LBO were performed by four surgeons. After tympanic curettage, a 1.9-mm rigid 30° endoscope was inserted into the rostral, caudal, dorsal, ventral, and medial sections of the tympanic cavity. Three observers evaluated otoscopic images for epithelial remnants in each compartment. The median distribution of epithelial remnants was calculated for each section of the tympanic cavity with a three-dimensional tympanic cavity model. Epithelial remnants were identified in at least one of the five areas of the tympanic cavity after each TECA-LBO. The rostral section contained the most epithelial remnants (35.6%), while the medial section contained the least amount (1.8%). Use of a 1.9-mm rigid endoscope was an effective method to evaluate all sections of the tympanic cavity after curettage in TECA-LBO. Epithelial remnants were consistently found after TECA-LBO, especially in the rostral compartment. Intraoperative endoscopy should be considered to improve removal of epithelium after initial TECA-LBO or revision surgeries.

Effects of fentanyl–lidocaine–ketamine versus sufentanil–lidocaine–ketamine on the isoflurane requirements in dogs undergoing total ear canal ablation and lateral bulla osteotomy

ObjectiveTo compare the isoflurane-sparing effects of sufentanil–lidocaine–ketamine (SLK) and fentanyl–lidocaine–ketamine (FLK) infusions in dogs undergoing total ear canal ablation and lateral bulla osteotomy (TECA–LBO). Study designRandomized blinded clinical study. AnimalsA group of 20 client-owned dogs undergoing TECA–LBO. MethodsIntravenous (IV) administration of lidocaine (3 mg kg–1) and ketamine (0.6 mg kg–1) with fentanyl (5.4 μg kg–1; n = 10; FLK group) or sufentanil (0.72 μg kg–1; n = 10; SLK group) was immediately followed by the corresponding constant rate infusion (CRI) (lidocaine 3 mg kg–1 hour–1; ketamine 0.6 mg kg–1 hour–1; either fentanyl 5.4 μg kg–1 hour–1 or sufentanil 0.72 μg kg–1 hour–1). Anaesthesia was induced with propofol 3–5 mg kg–1 IV and was maintained with isoflurane. End-tidal isoflurane concentration (Fe′Iso) was decreased in 0.2% steps every 15 minutes until spontaneous movements were observed (treated with propofol 1 mg kg–1 IV) or an increase of > 30% in heart rate or mean arterial pressure from baseline occurred (treated with rescue fentanyl or sufentanil). Quality of recovery and pain were assessed at extubation using the short-form Glasgow Composite Pain Scale (SF-GCPS), Colorado State University Canine Acute Pain scale (CSU-CAP), and visual analogue scale (VAS). Data were analysed with analysis of variance, t tests, Fisher test and Spearman coefficient (p < 0.05). ResultsFe′Iso decreased significantly in SLK group (45%; p = 0.0006) but not in FLK (15%; p = 0.1135) (p = 0.0136). SLK group had lower scores for recovery quality (p = 0.0204), SF-GCPS (p = 0.0071) and CSU-CAP (p = 0.0273) than FLK at extubation. Intraoperative rescue analgesia and VAS were not significantly different between groups. Conclusions and clinical relevanceCompared with FLK infusion, CRI of SLK at these doses decreased isoflurane requirements, decreased pain scores and improved recovery quality at extubation in dogs undergoing TECA–LBO.

Development and validation of an endoscopic myringotomy technique to treat otitis media and interna in a case series of three guinea pigs (Cavia porcellus)

ABSTRACT Background: Medical treatment of clinical otitis media and interna in guinea pigs is often unsatisfactory. Total ear canal ablation and lateral bulla osteotomy are used successfully in dogs, cats, and rabbits to treat chronic, medically nonresponsive ear disease. However, in guinea pigs this surgery can cause death. This study aimed to evaluate and describe a standardized myringotomy technique to treat guinea pigs with otitis media and interna. Methods: Ear dissections and endoscopically assisted myringotomy were evaluated on guinea pig carcasses to choose the most suitable endoscope and optics. Three client-owned guinea pigs with chronic otitis media and interna had a myringotomy with bacteriological sampling and therapeutic irrigation of the tympanic cavity performed. Anesthesia for the procedures was 25 minutes, the patients were recovered and eating within 2–6 hours, and discharged on targeted antibiotic therapy within 24 hours. Videotoscopy was performed at 7- and 14-days follow-up to assess the ear canal, healing of the tympanic membrane, and to evaluate the tympanic cavity. Repeat lavaging of the tympanic cavity was performed until the tympanic membrane incision was healed. Further follow-up occurred at 21- and 154-days postmyringotomy. Results: Two out of three guinea pigs had complete resolution of clinical signs, and the other showed clinical improvement from a 90° head tilt to a 30° head tilt. Conclusions and case series relevance: Videotoscopy assisted myringotomy under general anesthesia was a quick and straightforward endosurgical technique in three guinea pigs with chronic otitis media and interna. It allowed the collection of fluid for bacteriological culture and provided symptomatic relief.

Complication Rates After Bilateral versus Unilateral Total Ear Canal Ablation with Lateral Bulla Osteotomy for End-Stage Inflammatory Ear Disease in Dogs: 79 Ears.

To determine whether perioperative complication rates are different between unilateral (ULS) versus single-stage bilateral (BLSS) total ear canal ablation-lateral bulla osteotomy (TECA-LBO) surgeries. Retrospective case series. Fifity-seven dogs (79 ears) undergoing TECA-LBO at a single institution over 14 years. Medical records of dogs undergoing TECA-LBO for end-stage inflammatory non-neoplastic ear disease from March 1999 to September 2013 at the Colorado State University Veterinary Teaching Hospital were evaluated for intraoperative and early postoperative complications associated with the procedure. Inclusion criteria were clinical and/or histopathologic diagnosis of chronic otitis externa, surgical treatment by TECA-LBO, and a minimum of 2 week follow-up data. Twenty dogs (40 ears) underwent BLSS and 37 dogs (39 ears) had ULS. Complications were recorded for 29 of 40 ears (72.5%) in the BLSS group (40.0% facial nerve, 15.0% ocular, and 32.5% minor incisional complications) and 25 of 39 ears (64.1%) in the ULS group (33.3% facial nerve, 12.8% ocular, and 23.1% minor incisional complications). Dogs undergoing BLSS did not have a significantly higher total complication rate, or higher neurologic, ocular, or incisional complication rates, than the ULS procedure. No major anesthetic complications affecting outcome were recorded for either group. Anesthetic and early surgical complication rates after ULS and BLSS were not significantly different in our study. Offering single-stage bilateral TECA-LBO procedures for otherwise healthy dogs with end-stage inflammatory otitis externa is a viable treatment option without additional risk for complication.

Ablação total do canal auditivo externo aliada a osteotomia lateral da bula timpânica em gatos – revisão

Total ear canal ablation and lateral bulla osteotomy is a surgical procedure indicated for the treatment of chronic otitis externa and otitis media, aural polyps and neoplasia of external auditory canal in cats. Because of its complexity, there is potential risk of various surgical complications such as persistence or recurrence of infection, facial nerve damage, Horner’s syndrome, inner ear damage, auditory function impairment and poor ear carriage. Nonetheless, excellent results can be obtained by means of precise and meticulous surgical skills. Special attention should also be given to postoperative pain management due to the deep dissection in this kind of surgery. The aim of this review is to describe these feline ear diseases and the surgical technique of total ear canal ablation and lateral bulla osteotomy.

Diagnosis and surgical treatment of a malignant trichoepithelioma of the ear canal in a pet rabbit (Oryctolagus cuniculus)

A 10-year-old spayed female Holland Lop-mix pet rabbit (Oryctolagus cuniculus) was evaluated because of purulent-hemorrhagic discharge from the right ear canal and a suspected mass within that ear canal. Results of contrast-enhanced CT, video otoscopy, and histologic examination of endoscopic tissue biopsy samples indicated severe otitis media and externa and a benign trichoepithelioma of the right ear canal. Total ear canal ablation and lateral bulla osteotomy were performed. Histologic examination of a surgical biopsy sample of the mass indicated malignant trichoepithelioma. Tumor recurrence was detected 22 weeks after surgery. The rabbit was euthanized 33 weeks after surgery because of the large size of the recurrent tumor and declining quality of life. Necropsy findings indicated a malignant trichoepithelioma with local and lymphatic invasion into the right mandibular lymph node. This was the first report of the clinical diagnosis, surgical treatment, and outcome for a domestic rabbit with a diagnosis of a malignant trichoepithelioma of the ear canal and associated otitis media and externa. Neoplasia should be included as a differential diagnosis for pet rabbits with otitis externa and media. Although such tumors are typically benign, trichoepitheliomas in rabbits can be malignant. Computed tomography and histologic examination of tissue samples were useful diagnostic techniques, but histologic examination of an endoscopic biopsy sample did not allow identification of malignant characteristics of the trichoepithelioma.

Epineurial repair of an iatrogenic facial nerve neurotmesis after total ear canal ablation and lateral bulla osteotomy in a dog with concurrent cranio-mandibular osteopathy

A 7-year-old male entire West Highland white terrier was referred to the Small Animal Hospital at the University of Glasgow for bilateral, chronic, medically unresponsive otitis media and externa. A history of cranio-mandibular osteopathy was also reported. Bilateral total ear canal ablation and lateral bulla osteotomy was performed with the aid of a pneumatic burr. Extensive bone proliferation was present bilaterally originating from the caudal mandibular ramus and tympanic bulla which incorporated the horizontal canal on each side. The right facial nerve was identified leaving the stylomastoid foramen and running in a cranial direction through a 1.5 cm diameter cuff of bone surrounding the horizontal canal and external acoustic meatus. Despite careful dissection, a facial nerve neurotmesis ensued which required microsurgical epineurial repair. Neurologic examination performed 12 h post-operatively revealed abnormalities consistent with right facial nerve paralysis. At 3 months, the facial nerve function was found to have improved significantly and was assessed to be normal four months after surgery. To the authors' knowledge, this clinical communication described the first reported clinical case where unilateral facial nerve paralysis resulting from iatrogenic facial nerve neurotmesis was successfully treated by microsurgical epineurial repair.

Partial ear canal ablation and lateral bulla osteotomy in rabbits

Six lop rabbits were presented with clinical signs of otitis media or externa. The presence of disease was confirmed by computerized tomography examination, with two rabbits suffering from bilateral disease. The rabbits were anaesthetized and underwent surgery of the affected bulla. Rabbits with bilateral disease had a minimum of 2 weeks between procedures. A single vertical incision was made over the base of the vertical canal, which was bluntly dissected free from surrounding tissue. The ventral portion of the vertical canal was removed and a lateral bulla osteotomy was performed. The mucosa at the base of the dorsal vertical canal was apposed and the aural cartilage sutured to form a blind-ending pouch open at the pretragic incisure. Histopathological samples taken from the dorsal margin of the vertical canal yielded subtle and non-specific changes in the six samples submitted. All rabbits were discharged within 48 hours of surgery. The cosmetic outcome was excellent with animals retaining visually normal aural anatomy. The partial ear canal ablation/lateral bulla osteotomy procedure is quick and has a good cosmetic result when performed in rabbits.