Audiological findings in glomus tumours

Surgical management of tympanojugular paragangliomas using the flexible CO2 laser

PURPOSE

Surgery is a standard therapy for tympanojugular paragangliomas (TJP). Maintaining the quality of life (QoL) requires functional preservation. The flexible CO₂ laser allows contact-free tumor removal. This retrospective study compares the postoperative functional outcomes of TJP surgery with and without the flexible CO₂ laser.

METHODS

Between 2005 and 2019, 51 patients with TJP were surgically treated at a tertiary hospital. Until 2012, 17 patients received conventional surgery. Thereafter, the flexible laser was used in 34 patients. Tumor extend, pre- and postoperative cranial nerve function, and complications were compared between the groups.

RESULTS

The cohort consisted of 33 class A and B tumors and 18 class C and D tumors. Preoperative embolization was performed in 17 cases. Class C/D TJP were usually removed via an infratemporal fossa type A approach. Gross total tumor removal was achieved in 14/18 class C/D tumors. 3/51 patients suffered from long-term partial or complete facial palsy. No differences in post-therapeutic cranial nerve function or complications were noted between the conventional and laser group. One recurrence was observed after complete tumor resection.

CONCLUSION

The flexible CO₂ laser was shown to be a safe and effective alternative to conventional bipolar cauterization, which is appreciated by the surgeon in these highly vascularized tumors. Both techniques allowed a high tumor control rate and good long-term results also from a functional point of view.

Stereotactic radiosurgery for head and neck paragangliomas: a systematic review and meta-analysis

Head and neck paragangliomas (HNPs) are rare, usually benign hyper vascularized neuroendocrine tumors that traditionally have been treated by surgery, with or without endovascular embolization, or, more recently stereotactic radiosurgery (SRS). The aim of our study is to determine the clinical and radiographic effectiveness of SRS for treatment of HNPs. A systematic search of electronic databases was performed, and 37 articles reporting 11,174 patients (1144 tumors) with glomus jugulare (GJT: 993, 86.9%), glomus tympanicum (GTT: 94, 8.2%), carotid body tumors (CBTs: 28, 2.4%), and glomus vagale (GVT: 16, 1.4%) treated with SRS definitively or adjuvantly were included. The local control (LC) was estimated from the pooled analysis of the series, and its association with SRS technique as well as demographic and clinical factors was analyzed. The median age was 56 years (44-69 years). With a median clinical and radiological follow-up of 44 months (9-161 months), LC was 94.2%. Majority of the patients (61.0%) underwent Gamma Knife Radiosurgery (GKS), but there was no statistically significant difference in LC depending upon the SRS technique (p = 0.9). Spearmen's correlation showed that LC was strongly and negatively correlated with multiple parameters, which included female gender (r = - 0.4, p = 0.001), right-sided tumor (r = - 0.3, p = 0.03), primary SRS (r = - 0.5, p ≤ 0.001), and initial clinical presentation of hearing loss (r = - 0.4, p = 0.001). To achieve a LC ≥ 90%, a median marginal dose (Gy) of 15 (range, 12-30 Gy) was required. The results corroborate that SRS in HNPs is associated with good clinical and radiological outcome.

Pulsatile Tinnitus and the Intrameatal Vascular Loop: Why Do We Not Hear Our Carotids?

OBJECTIVE:

Pulsatile tinnitus is characterized by hearing the heart beat or respiration in one or both ears. In 15% of patients with pulsatile tinnitus, no cause can be found. Other investigators have suggested that a vascular loop entering the internal auditory meatus can be another cause of arterial, pulse synchronous tinnitus. If so, we should constantly hear the arterial pulsations of the carotid arteries passing through the petrous bone.

METHODS:

Using magnetic resonance imaging, 17 patients with unilateral pulsatile tinnitus and 46 with non-pulsatile tinnitus were analyzed for the presence of a vascular loop entering into the internal acoustic meatus. Four temporal bones were sectioned to find structural differences between the internal acoustic meatus and the pericarotid area. Four patients with intrameatal vascular loops and ipsilateral pulsatile tinnitus underwent surgery by Teflon interpositioning between the loop and the cochlea.

RESULTS:

In unilateral pulsatile tinnitus, a statistically highly significant amount of intrameatal vascular loops was noted in comparison to non-pulsatile tinnitus. A well-developed pericarotid venous plexus was found histologically. Three of the four patients who underwent surgery were initially tinnitus free, but pulsations recurred after 3 months in one patient.

CONCLUSION:

Vascular loops in the internal auditory canal may generate pulsatile tinnitus. It may be treated by placing Teflon between the cochlea and the intrameatal vascular loop. One then does not hear the pulsation of the carotids due to a dampening effect of a pericarotid venous plexus.

[Tympanic paragangliomas: analysis of a nine cases]

OBJECTIVE

The purpose of this work was to evaluate the diagnostic strategy and outcome of patients treated for tympanic paraganglioma.

PATIENTS AND METHODS

Nine patients presented with tympanic paraganglioma were treated in our unit from 1996 to 2003. There were eight women and one man, mean age 65 years. Surgery was performed in all nine patients. This retrospective analysis focused on revealing signs, diagnostic tools, surgical procedure for tumor resection, and short-, mid-, and long-term functional outcome.

RESULTS

The surgical procedure was well tolerated by all patients. There were no cases of postoperative mastoiditis. None of the patients experienced postoperative dizziness. Total tumor removal was achieved in seven patients. In one patient, incomplete tumor resection was decided in order to preserve facial motion. All patients but one were relieved from their tinnitus in the early postoperative period. In four patients, preoperative hearing levels were worsened by the surgical procedure, essentially through an alteration of preoperative conductive hearing loss.

CONCLUSION

MRI is highly contributive to the diagnosis of tympanic paraganglioma, which should be evoked in patients with pulsatile tinnitus. Diagnosis should be established as early as possible to lower the postoperative morbidity. While surgery can provide cure and relieve tinnitus, there is a high risk of auditory deterioration.

Laser excision of glomus tympanicum tumours: long-term results

The purpose of this study was to evaluate the long-term results of laser excision of glomus tympanicum tumours in a series of patients who had been referred to the senior author (DAM) in a retrospective case review. Nine patients underwent complete excision of their glomus tympanicum tumours using a Diode or KTP laser. There were no cases of tumour recurrence. There were no complications during the peri- or postoperative period. Follow-up time was 31.8 months. In our experience, laser excision can be performed with minimal bleeding and morbidity, and it provides excellent tumour control in glomus tympanicum surgery.

The effect of lidocaine on chronic tinnitus: a quantitative cerebral perfusion study

The cerebral perfusion of a 55-year-old female patient with chronic tinnitus was investigated quantitatively by single photon emission computed tomography (SPECT) with the xenon133 inhalation method. The first investigation was performed under standard conditions, the second during suppression of tinnitus with intravenous injection of lidocaine. As a reference a healthy volunteer was included under the same conditions. The global cortical perfusion was identical on both sides except for increased perfusion in the auditory cortex, especially on the right side when tinnitus lasted during the first measurement. The second investigation under treatment with lidocaine and during the tinnitus-free interval showed a decrease of the global cortical perfusion with a slightly higher value at the temporal cortex bilaterally. In comparison to the first investigation, a difference between right and left auditory cortex could no longer be demonstrated, and also the difference between regional and global perfusion decreased. A cerebral effect under treatment of tinnitus with lidocaine was shown by the quantitative measurement of brain perfusion. It is debatable whether this effect on cerebral activity results from the medication or as a reaction to the tinnitus-free interval.