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In this study, we aimed to assess anatomical relationship between the anterior inferior cerebellar artery (AICA) and cochleovestibular nerve (CNV) in patients with non-specific cochleovestibular symptoms using magnetic resonance imaging (MRI). One-hundred and forty patients with non-specific neuro-otologic symptoms were assessed using cranial and temporal MRI. Classification was performed according to four different types of anatomical relationship observed between the AICA and CVN. In type 1 (point compression), the AICA compresses only a limited portion of the CVN. In type 2 (longitudinal compression), the AICA approaches the CVN as both traverse parallel to each other. In type 3 (loop compression), the vascular loop of the AICA encircles the CVN. In type 4 (indentation), the AICA compresses the CVN so as to make an indentation in the nerve. The anatomical relationship between the CVN and AICA was encountered in 19 out of 140 (13.6%) patients (20 ears). The VCC was unilateral in 18 patients (94.7%) and bilateral in one patient (5.3%). There was no other vascular structure causing VCC to the CVN except for vertebral artery that was seen in 2 out of 140 patients (1.4%). These were unilateral cases. There were tinnitus, vertigo or dizziness, hearing loss, and both hearing loss and vertigo in 5 (25%), 13 (65%), 1 (5%) and 1 (5%) ears of 20 patients, respectively. There was no relationship between the cochleovestibular symptoms and type of compression (p > 0.05). Neurovascular relationship between the CVN and AICA can be imaged properly using MR and MR based classification may help reporting this relationship in a standard way. Although, MR images can show the anatomical relationship accurately, diagnosis of vascular conflict should not be based on imaging findings alone.

We assessed the mastoid air cell size and variables of the sigmoid sinus in healthy ears and ears with chronic otitis media (COM). Thirty-eight patients with unilateral COM [15 with cholesteatoma (COM/+) and 23 without cholesteatoma (COM/-)], and 20 subjects with healthy ears, were included in the study. Assessment was performed using a quantitative digital image processing computed tomography (CT) program, and the volume of the mastoid bone was measured using the morphometric method of Cavalieri. In both COM/+ and COM/- patients the sigmoid to suprameatal spine distance and mastoid size were greater on the healthy side than on the diseased side ( p0.05). The distance and area were significantly greater in the healthy control subjects than in either the healthy or the diseased ears of the patients with COM ( p0.05). In the healthy ears of COM patients, there was significant correlation between the sigmoid to suprameatal spine distance and air cell size and mastoid volume ( p0.05). In the diseased ears of COM patients, this correlation was absent ( p0.05). The sigmoid sinus shape was of the half-moon type (62%), protrusive type (22%) and saucer type (16%). The digital image processing CT program allowed us to estimate the individual area of the air and soft tissue filled mastoid air cells. The mastoid size in both intact and disease ears of COM patients was smaller than in the healthy controls. The mastoid size may be determined genetically. However, environmental factors such as infection may also affect the mastoid size. Therefore, both genetic and environmental factors may be related to COM as far as the size of the mastoid air cells is concerned.

To determine the standard width and shape of the nasolacrimal canal (NLC) in the coronal plane, a retrospective review of 950 coronal paranasal CT sections was undertaken. The coronal diameter of NLC was measured at its upper and lower ends and anomalies in its configuration noted. The mean diameters of the NLC were 4.8 +/- 1.2 mm and 4.7 +/- 1.1 mm on the right and left sides, respectively. There was no difference in the mean NLC diameter between the right and left sides, upper and lower portions or males and females. In two cases, an abnormal dilation of the NLC at its inferior portion was encountered. A marked enlargement of the NLC can occur in the absence of a neoplastic or obstructive process and may be detected as an isolated finding representing idiopathic or congenital enlargement. Segmental NLC dilatation is not always an indicator of pathology, particularly in asymptomatic cases, and should be considered a rare anatomic variation.

The aim of this study was to determine whether a relationship exists between mastoid size and auditory tube angle (ATA) and chronic ear disease. A radiological and clinical study was undertaken of the temporal bones of 36 subjects. There were 24 patients with unilateral chronic otitis media (COM) and 12 healthy controls (HC): the contralateral healthy ears of the COM patients were also used as control (CLHC). From each CT scan the distance between Henle spine and the sigmoid sinus (H-SS) and the ATA was assessed. The angle between a longitudinal line bisecting the transverse length of the external auditory canal and the longitudinal axis of the AT was calculated. A direct correlation between H-SS and ATA, both in COM and HC (p < 0.01), was observed, but not in CLHC (p > 0.05). There was no significant difference in the ATA results between COM and CLHC, or between COM and HC (p > 0.05), however there was a significant difference between CLHC and HC (p = 0.02). H-SS distances were not significantly different between COM and CLHC, or COM and HC, or CLHC and HC (p > 0.05). An association between ATA and mastoid size in both healthy and diseased ears was observed. The anatomical relationships of the AT, mastoid and middle ear, which form a functional unit, are not significantly important in chronic ear disease.

The purpose of this study was to discover the prevalence of maxillary sinus hypoplasia (MSH) and associated malformations. A total of 490 consecutive axial and coronal computerized tomographic (CT) scans of the paranasal sinuses were obtained from patients with chronic sinusitis. CT scans were assessed for the presence of MSH and associated anatomic variations. A new classification of MSH was made, and the diagnostic criteria listed. The frequency of anatomic variations coexisting with MSH was also estimated. MSH was encountered in 21 (4.2%) of the 490 patients. Unilateral types I, II and III MSH were seen in 7 (1.4%), 6 (1.2%) and 8 (1.6%) respectively. MSH was bilateral only in 3 (0.6%) patients, one of which was a bilateral type II. In the remaining two bilateral MSH cases, there was a type II MSH on one side and type III MSH on the other in each patient. Middle conchal pneumatization was the most common coexisting anatomic anomaly in MSH, followed by agger nasi cell, secondary middle concha, paradoxical middle concha and superior conchal pneumatization. A patient with MSH should be carefully evaluated prior to any sinus surgery in order to avoid surgical complications. With precise CT assessments, an MSH can be diagnosed and distinguished from other maxillary sinus anomalies. With the additional criterion of orbital enlargement, and the help of reproducible measurement techniques explained in this study, an objective diagnosis and classification can be made in further investigations of MSH.