Subjective pulsatile tinnitus associated with extensive pneumatization of temporal bone

A Message from a Narrowed Internal Auditory Canal in a Patient with a Hyperpneumatized Petrous Bone

Hyperpneumatization of the temporal bone (HPTB) is a rare finding, and its clinical impact is poorly described in literature. We report the case of a 34-year-old woman with no previous otologic condition, complaining of paroxysmal vertigo and right pulsatile tinnitus shortly after a first scuba diving session. Clinical neurotologic assessment found a right vestibular impairment. Cranial tomodensitometry showed a bilateral hyperpneumatization of the petrosal air cell system. Brain magnetic resonance imaging to rule out any retrocochlear pathology was normal, although the cochleo-vestibular nerve (CVN) appeared to be over lengthened in a narrowed internal auditory canal (IAC), especially on the right-hand side. Pain was alleviated by administration of a low-dose anti-epileptic drug. The clinical, neurological, and radiological findings evoked a right vestibulopathy generated by a limited compression of the CVN; HPTB appeared to contribute to the narrowing of the IAC, especially on the right-hand side.

A study on relationship between pulsatile tinnitus and temporal bone pneumatization grade

Pulsatile tinnitus (PT) is a common symptom in otology. In some cases, the venous flow in the sigmoid sinus (SS) is the source of PT. It is suggested that the venous sound is propagated into the tympanic cavity through the air pathway of temporal bone air cells (TBAC). The hyperpneumatization of TBAC was hypothesized as a direct pathology of PT through amplifying the venous sound, but there is no quantitative analysis. This study aims to quantify the relationship between the venous sound amplification and the pneumatization grade of TBAC. The acoustic numerical simulation and statistical analysis were performed based on the radiology data of 21 pulsatile tinnitus patients. The TBAC of these patients were classified into hypopneumatization, normal pneumatization and hyperpneumatization grades according to three standards. The in vitro acoustic experiment was done as the validation of simulation. It is indicated that the SS standard is effective for the clinical evaluation of venous sound amplification. The TBAC amplifies the venous sound due to the acoustic resonance at the first mode frequency, regardless of the pneumatization grades. The normal pneumatic TBAC exhibits the highest sound amplification effect on the venous sound amongst the three grades, contributing mostly to PT, but would not induce PT without any other causes.

Aberrant sylvian vein: A newly described cause of pulsatile tinnitus

We herein report a newly described cause of venous pulsatile tinnitus: protrusion of an aberrant sylvian vein into the tympanum. A 60-year-old woman presented with a 4-month history of objective persistent pulsatile tinnitus in the right ear with no other complaints. The pulsatile tinnitus diminished with rotation of the head to the right side or by compression of the right cervical vascular structures. The frequency and intensity of the tinnitus were 125 Hz and 20 dB HL, respectively. Audiometry and otoscopic examination findings were normal. Radiologic examination showed that the right sylvian vein protruded into the tympanum through the dehiscent anterior cortical plate of the tympanum.

CT characteristics of dehiscent sigmoid plates presenting as pulsatile tinnitus: a study of 23 patients

BACKGROUND

Although some features of dehiscent sigmoid plates as a cause of pulsatile tinnitus (PT) have been reported, detailed imaging findings have not been evaluated.

PURPOSE

To retrospectively evaluate the computed tomography (CT) features of dehiscent sigmoid plates associated with PT.

MATERIAL AND METHODS

The CT images of 23 PT patients were assessed to evaluate the features of the dehiscent sigmoid plates, lateral sinuses, and temporal bone pneumatization.

RESULTS

A total of 31 defects were found on the PT side. Twenty-five defects involved the superior curve or the descending segment, four involved above both sites, and only two involved the inferior curve. Twenty-six defects involved the anterior border or the anterolateral border, and only five involved the lateral border of the sigmoid sinus. The dehiscent sigmoid plate was on the dominant side in all 18 patients with a unilateral dominant lateral sinus, and on the right side in two patients and on the left side in three patients with co-dominant lateral sinuses. Fourteen patients had hyperpneumatization and nine had good pneumatization of temporal bone. Fifteen of the 17 patients with resolution of PT after surgery had a single defect. Four of the six patients with persistence of PT after surgery had more than one defect.

CONCLUSION

Sigmoid plate dehiscence often involves the anterior or anterolateral border of the superior curve or the descending segment of the sigmoid sinus on the side of the dominant lateral sinus, which often coexists with extensive pneumatization of the temporal bone.

Sigmoid plate dehiscence: congenital or acquired condition?

BACKGROUND AND PURPOSE

The imaging features of sigmoid plate dehiscence-induced pulsatile tinnitus have been presented. The origin of the sigmoid plate dehiscence, however, remains unclear. Our aim was to assess the prevalence and extent of sigmoid plate dehiscence on computed tomography (CT) images in multiple age groups to determine whether this condition is more likely to be congenital or acquired.

MATERIALS AND METHODS

We retrospectively reviewed contrast-enhanced CT images of sigmoid plates of temporal bones in 504 patients. Each temporal bone was characterized as normal or dehiscent. Patients were then subcategorized into four age groups, and the prevalence and extent of dehiscent sigmoid plates in each group were calculated and compared.

RESULTS

Overall, 80 patients had sigmoid plate dehiscence, nine of whom had it bilaterally. In successively older age groups, the prevalences of sigmoid plate dehiscence were 18.9%, 20.1%, 14.5%, and 12.7%, respectively. Respective average anteroposterior bony defect diameters were 3.7±1.7, 3.0±1.3, 3.1±1.5, and 3.0±1.1 mm. Respective average vertical bony defect diameters were 3.6±2.3, 2.6±1.2, 3.2±1.5, and 3.0±1.7 mm. The prevalence and extent of sigmoid plate dehiscence were not statistically different among the four age groups.

CONCLUSIONS

The similar radiologic prevalence and extent of dehiscent sigmoid plates among the age groups suggest that the dehiscence is more commonly a congenital than an acquired condition.

Temporal Bone Pneumatization and Pulsatile Tinnitus Caused by Sigmoid Sinus Diverticulum and/or Dehiscence

BACKGROUND

Although air cells within temporal bone may play an important role in the transmission of pulsatile tinnitus (PT) noise, it has not been studied systematically.

PURPOSE

To evaluate the difference in temporal bone pneumatization between PT patients with sigmoid sinus diverticulum and/or dehiscence (SSDD) and healthy people.

MATERIAL AND METHODS

A total of 199 unilateral persistent PT patients with SSDD and 302 control subjects underwent dual-phase contrast-enhanced CT (DP-CECT), to assess the grade of temporal bone pneumatization in each ear.

RESULTS

In the bilateral temporal bone of 302 controls, 16 ears were grade I, 53 were grade II, 141 were grade III, and 394 were grade IV. Among the affected ears of 199 PT cases, 1 ear was grade I, 18 were grade II, 53 were grade III, and 127 were grade IV. There was no significant difference in the pneumatization grade between the affected PT ear and either ear in the healthy subjects (p > 0.05).

CONCLUSION

Although air cells within the temporal bone are an important factor in the occurrence of PT, its severity does not differ significantly from the pneumatization of healthy people.

Petrosquamosal sinus in the temporal bone as a cause of pulsatile tinnitus: a radiological detection

We report a newly evidenced cause of venous pulsatile tinnitus--the petrosquamosal sinus in the temporal bone. We also present the case of a 45-year-old woman who presented with an incapacitating objective pulsatile tinnitus in the left ear for 10 years. The radiology evidenced a petrosquamosal sinus in the air cells of the left temporal bone. The symptoms of pulsatile tinnitus disappeared completely after surgical treatment.

Subjective pulsatile tinnitus associated with extensive pneumatization of temporal bone

Pulsatile tinnitus (PT), a rare otologic symptom, is frequently associated with identifiable and treatable causes. We report two cases of subjective PT due to extensive pneumatization of temporal bone around the internal carotid artery.