Both carotid canal dehiscence (CCD) and high jugular bulb (HJB) are thought to increase the potential for disastrous consequences during middle ear surgery. Clinical co-presentation of these two great vessel variants has not yet been described. This study aims to determine the relationship between CCD and HJB based on a computed tomographic (CT) temporal bone evaluation. High-resolution CT scans of 408 temporal bones obtained from 208 adults were recruited. Carotid canal integrity, jugular bulb position, petrous apex pneumatization and the minimal thickness of the carotid canal wall (TCW) facing the tympanic cavity were examined and measured for the incidence of CCD and/or HJB. Other variables including gender, age, laterality and the presence of otitis media or mastoiditis were also collected for analysis. CCD was found in 28 ears (6.9%); 19 of these were found to also have HJB (67.9%). The presence of CCD was significantly correlated with HJB presentation. The minimal TCW in HJB ears was significantly thinner than that of normally positioned jugular bulbs. Moreover, after controlling for other candidate variables, the independent factors of age (younger or older than 50 years) and jugular bulb position (high vs. normal) were found to predict the presence of CCD. In conclusion, HJB tends to coexist with a thinner carotid canal wall. This finding emphasizes the need to be watchful for the coexistence of these two great vessel anomalies when surgeons encounter an aged patient presenting either CCD or HJB during middle ear surgery.

ObjectivesWe evaluate the long-term surgical and hearing results using a canal wall down mastoidectomy technique followed by cavities obliteration, canal wall reconstruction and ossiculoplasty without staging.MethodsA total of 44 patients between January 2002 and October 2009 were selected and 27 of them were revision cases. Preoperative and postoperative pure tone average (PTA) and air-bone gap (ABG) were assessed and compared 1 and 4 years after surgery.ResultsThe middle ear was well healed and aerated in 40 patients (90.9%) and the tympanic membrane was intact in 42 patients (95.5%). Recurrent cholesteatoma was found on postoperative follow-up in two of the revision patients (7.4%) but none in the primary patients. Seven patients were found to have partial canal bone absorption, but revision surgery was not required. Over 86.4% of all cases were water resistant. Long-lasting improvement and/or preservation of hearing, with maintenance of PTA-ABG closure in 63.7% of all cases within 20 dB, were obtained.ConclusionThe efficacy of our technique after a canal wall down mastoidectomy is satisfactory, and the rate of complication is acceptably low. We believe that our technique could be a convenient method in disease control and providing an excellent basis for hearing restoration simultaneously.