Adenoid cystic carcinoma of the external auditory canal: correlation between histological features and MRI appearances

A rare case of adenoid cystic carcinoma of the external auditory canal with magnetic resonance imaging appearances is reported. Both T1 weighted and T2 weighted MR images showed the tumour as a hypointense mass, although there was marked contrast enhancement. Microscopic examination of the resected tumour showed a preponderance of solid tumour cell nests. According to previous reports, these pathological and radiological findings indicate a poor prognosis.     

Lipomas of the internal auditory canal and cerebellopontine angle

OBJECTIVE: To evaluate lipomas of the internal auditory canal (IAC) and cerebellopontine angle (CPA). STUDY DESIGN: Retrospective review. METHODS: Review of a multi-institutional series of 17 lipomas of the IAC/CPA, combined with a Medline review of the 67 cases reported in the world literature. RESULTS: This series of 17 IAC/CPA lipomas is the largest reported series to date, bringing the total number of documented cases to 84. There appears to be a nearly 2:1 male to female predominance. Sixty percent were left-sided lesions, and three were bilateral. Hearing loss, dizziness, and tinnitus were the most common presenting symptoms. Surgical resection was performed in 52 (62%) of these lesions; however, total tumor removal was accomplished in only 17 (33%), which is most likely because of the fact that these tumors tend to have a poorly defined matrix and a dense adherence to neurovascular structures. Sixty-eight percent of patients experienced a new deficit postoperatively, 11% were unchanged, and only 19% improved with no new deficit. Only one documented case of tumor growth was identified; however, the reported follow-up was short (average, less than 3 years). CONCLUSION: With the magnetic resonance imaging techniques now available, lipomas can be reliably differentiated from other masses within the CPA and IAC, so histopathologic diagnosis is rarely necessary. Because of the potential for significant morbidity with resection of these lesions, we believe that conservative follow-up is the best treatment option for patients with these rare lesions. Surgery is indicated only when significant progressive or disabling symptoms are present.     

Cerebellopontine angle ependymoma with internal auditory canal enlargement and pineal extension--case report

A 38-year-old male presented with a posterior fossa ependymoma with unusual extension from the cerebellopontine angle to the pineal region. Magnetic resonance imaging clearly demonstrated that these two components were continuous through the right ambient cistern. Computed tomography using a bone algorithm revealed enlargement of the right internal auditory canal. This case suggests that ependymoma can extend anywhere within the subarachnoid space along the path of least resistance.     

Chondroma of the external auditory canal

Chondroma, a benign tumour which is common at many sites in the body, has not been reported in the English literature in the bony external auditory canal. The first such case at this anatomical site is described and the pathogenesis is considered.     

Paraganglioma of the external auditory canal

A rare case of paraganglioma of the external auditory canal is presented. It was treated by excision and no recurrence has been noted after 18 months of follow up.     

Colo-anal sleeve anastomosis in the treatment of diffuse cavernous haemangioma involving the rectum

An operative technique, involving a colo-anal sleeve anastomosis, is described for the treatment of cavernous haemangioma of the rectum. All the patients with this condition treated since 1930 at St Mark's Hospital are reviewed, and the presentation and results of treatment in the last 5 patients who have had a resection and colo-anal sleeve anastomosis are discussed.     

Hemorrhage in cavernous hemangioma of the adrenal gland: US, CT and MRI appearances with pathologic correlation

A total of 374 dogs, 252 from five military kennels and 122 privately owned, were tested for Ehrlichia canis antibody. Sera were tested at a 1:20 dilution by indirect fluorescent antibody with the use of E. canis cell-culture antigen slides. The overall prevalence of E. canis antibody was 33%. Antibody prevalence among military dogs (29%) was significantly lower than among privately owned dogs (41%; P < 0.05). The E. canis seroprevalence among dogs infested with ticks (Rhipicephalus sanguineus) was higher (44%) than that among uninfested dogs (31%; P = 0.08). The seroprevalence among military dogs varied from 21-46% at the five kennels; lower prevalences were observed in kennels with higher sanitary and hygienic conditions. Age- and sex-related E. canis antibody prevalences were not significantly different among military and privately owned dogs, although adult and male privately owned dogs had the highest seroprevalences (45% and 44%, respectively). Three dogs with epistaxis had E. canis antibody titres > 1:320. These data demonstrate the first laboratory evidence of E. canis infection among dogs in Egypt.     

Morphological and clinical study of acoustic tumor with respect to enlargement of internal auditory canal: mechanism of bone destruction

The mechanism of widening of the internal auditory canal (IAC) by an acoustic tumor is still unknown. Degree of IAC enlargement was expressed as "IAC ratio' calculated from the measurement of bilateral horizontal diameters from bone-imaging CT. Comparing IAC ratio to radiological findings of tumors, such as size, solidity, mode of attachment to pyramidal bone and the presence of ventricular dilatation, we found a positive correlation between the ratio and the volume of solid tumors (especially of smaller ones) and more marked destruction of IAC in association with ventricular dilatation. Preoperative degrees of hearing ability or facial nerve function didn't correlate with that of IAC enlargement. It is our hypothesis that the mechanism involved in the destruction of IAC is as follows: (1) The repeated strokes of the tumor caused by brain pulsation gradually erode the bony wall of IAC (especially, that of the posterior wall). The apparently less destruction of IAC in cases with mostly cystic large tumors might be due to the restriction of this pulsatile movement. (2) Increased CSF pressure on the site has some influence on the mechanism of bone erosion as also does solidity of the tumor.     

Fiberscope-assisted evaluation of prereconstructed and postreconstructed external auditory canal

The malignant tumors of the external auditory canal often invade the middle ear area through the narrow canal, so it is difficult to determine the surgical excisional margin. A patient undergoing external auditory canal reconstruction following excision of a squamous cell carcinoma using a chondrocutaneous flap and fiberscope-assisted preoperative and postoperative diagnoses are described. We obtained good patency of the canal postoperatively. This technique is quite simple and easy to use. We believe fiberscope-assisted surgery is useful for extracting lesions in small areas. In the future, its application will extend to the area of plastic surgery.     

Fibrous dysplasia of the temporal bone: reversal of sensorineural hearing loss after decompression of the internal auditory canal

When fibrous dysplasia affects the temporal bone, it most often presents with conductive hearing loss attributable to stenosis of the external auditory canal. Sensorineural hearing loss has usually been attributed to involvement of the otic capsule. We present a patient with bilateral fibrous dysplasia of the temporal bones who complained of unilateral hearing loss, facial tingling, and facial twitching. The audiogram showed severe sensorineural hearing loss. The hearing markedly improved and facial twitching and tingling ceased after decompression of the internal auditory canal via a middle fossa approach. This is the only case of which we are aware showing reversal of sensorineural hearing loss caused by fibrous dysplasia.     

Impression-material foreign bodies of the middle ear and external auditory canal

Twenty-nine evaluable patients with endometrial cancer were treated with amonafide 300 mg/m2 for 5 consecutive days every 3 weeks. Two partial responses (8%) were seen. Hematologic toxicity was severe or life-threatening in 13 patients occurring as follows: leukopenia in 13 patients (45%); thrombocytopenia in 10 patients (34%); granulocytopenia in 13 patients (45%); and anemia in four patients (14%). In view of the low response rate and high toxicity, this dose schedule of amonafide does not warrant further investigation in endometrial cancer.