Stereotactic Radiosurgery and Radiotherapy for Vestibular Schwannoma in NF2-Related Schwannomatosis

OBJECTIVES

To determine the long-term control rates and hearing outcomes for growing vestibular schwannoma in NF2-related schwannomatosis (NF2) treated with stereotactic radiosurgery (SRS) and fractionated radiotherapy (FRT).

METHODS

Retrospective review of all patients treated with SRS/FRT between 1986 and2021 from a tertiary NF2 unit. Overall tumor control was defined as: (1) growth control (growth failure was defined as growth in any dimension of 3 millimetres or more from baseline post-SRS/FRT), and (2) treatment control (no need for further intervention). Loss of serviceable hearing was defined as a drop in speech discrimination score below 50% after SRS/FRT.

RESULTS

There were 81 cases, with a mean duration of follow-up of 125 months. Overall control rate was 72% (58/81), with 80% (65/81) growth control and 74% (60/81) treatment control. There was a 5-year actuarial survival of 77% and 10-year survival of 71%. Forty-three percent (30/69) of cases did not have serviceable hearing at baseline. Of those remaining, 49% (19/39) preserved serviceable hearing during follow-up at a mean of 106 months. Actuarial survival for preservation of serviceable hearing at 5 and 10 years was 69% and 53%. There were poorer outcomes with increasing genetic severity, and with baseline tumor size >3 cm. No cases of SRS/FRT-related malignancy were identified at a mean follow-up of 10 years.

CONCLUSION

Stereotactic radiosurgery/fractionated radiotherapy are an effective option to treat growing vestibular schwannoma in patients with NF2 with the potential for hearing preservation in a proportion of patients.

LEVEL OF EVIDENCE

4-Case Series Laryngoscope, 134:2364-2371, 2024.

Radiation treatment of benign tumours in NF2-related-schwannomatosis: a national study of 266 irradiated patients showing a significant increase in malignancy/malignant progression

Background

Radiation treatment of benign tumours in tumour-predisposition syndromes is controversial, but short-term studies from treatment centres suggests safety despite apparent radiation associated malignancy being reported. We determined whether radiation treatment in NF2-related-schwannomatosis patients is associated with increased rates of subsequent malignancy-(M)/malignant progression-(MP).

Methods

All UK patients with NF2 were eligible if they had a clinical/molecular diagnosis. Cases were NF2 patients treated with radiation for benign tumours. Controls were matched for treatment location with surgical/medical treatments based on age and year of treatment. Prospective data collection began in 1990 with addition of retrospective cases to 1969. Kaplan-Meier analysis was performed for malignancy incidence and survival. Outcomes were CNS M/MP (2cm annualised diameter growth) and survival from index tumour treatment.

Results

1345 NF2 patients, 266 (133-Male) underwent radiation treatments between 1969-2021 with median first radiotherapy aged 32.9-(IQR=22.4-46.0). Nine subsequent CNS malignancies/malignant progressions were identified in cases with only four in 1079 untreated-(p<0.001). Lifetime and 20-year CNS M/MP was ~6% in all irradiated patients-(4.9% for VS radiotherapy) versus <1% in the non-irradiated population-(p<0.001/0.01). Controls were well-matched for age at NF2 diagnosis and treatment-(Males=133-50%) and had no M/MP in the CNS post index-tumour treatment-(p=0.0016). Thirty-year survival from index tumour treatment was 45.62%-(95%CI=34.0–56.5) for cases and 66.4%-(57.3–74.0) for controls-(p=0.02), but was non-significantly worse for VS radiotherapy.

Conclusion

-NF2 patients should not be offered radiotherapy as first line treatment of benign tumours and should be given a frank discussion of the potential 5% excess absolute risk of M/MP.

Assessing the risk of magnetic interaction between auditory implants and programmable ventriculoperitoneal shunts

PURPOSE

This study investigated whether the magnetic field of the internal magnet of cochlear implants and bone-anchored hearing aids (BAHA) would be sufficient to affect a programmable ventriculoperitoneal (VP) shunt. Current guidelines suggest against implanting these hearing devices ipsilateral to a programmable VP shunt, but the exact nature of the interaction has not been quantified.

METHODS

The magnetic field strength (mT) was measured at 0 and 10 mm from the edge of both the Cochlear Implant CI512 (Cochlear Corporation) magnet and BAHA Attract magnet. Next, the hearing devices were placed into their anatomical positions in a 3-D clay model, along with three different types of programmable VP shunts. The valve setting was measured before and after exposure.

RESULTS

At 10 mm, neither device generated a magnetic field sufficient to adjust the VP shunt valve. In the clay model, the valve settings were not affected by the presence of any device.

CONCLUSION

Neither the cochlear implant nor the BAHA subcutaneous internal magnets generated sufficient magnetic field to reprogramme the valves of commonly used programmable VP shunts. The magnetic field from each device decreases dramatically at 10 mm. Further clinical studies to help mitigate the current restrictive guidance should consider involvement of VP shunt manufacturers to inform future shunt development and design.

The relationship between pressure and volume when using Rapid Rhino(r) packs in the management of epistaxis

Despite the popularity of Rapid Rhino packs, there are no clear guidelines regarding the volume of air to be inflated when used in the management of epistaxis. The manufacturers suggest that subjective assessment by pilot cuff palpation is used to guide inflation. However, studies have clearly demonstrated that clinicians are poor at judging balloon pressure by pilot cuff palpation when used in other settings. Our objective was to investigate the relationship between the volume of air inflated and the resultant intra-nasal pressure generated by nasal balloon packing. Twelve healthy subjects were packed with 5.5 cm Rapid Rhino packs, which were connected to a manometer and 20 ml syringe via a 3-way tap in a closed circuit. Increments of 2.5 mls of air were inflated and the resultant intra-nasal pack pressure was measured. There appeared to be a linear relationship between increasing volume and pack pressure. However, between individuals, there was a large variation in the intra-nasal pack pressure produced for a given fixed volume of air inflated. This is presumably due to variations in nasal anatomy. It may be that a manometer-measured, pressure guided nasal pack inflation technique would represent best practice, especially for less experienced staff.

Pre-operative imaging for cochlear implantation: magnetic resonance imaging, computed tomography, or both?

OBJECTIVE

Previous studies of computed tomography (CT) and magnetic resonance imaging (MRI) before cochlear implantation have been of limited sample size, lacked statistical analysis, and been inconsistent in their conclusions. We aim to quantify the utility of CT, MRI, and their combination in order to rationalize their selection.

METHODS

Clinical records and radiological findings were correlated retrospectively in 158 adults and children. All underwent both CT and MRI.

RESULTS

A total of 27.9% (95% confidence interval (CI): 21.0-35.5) of patients had a significant radiological abnormality, but these were considered critical to subsequent management in only 12.7% (7.9-18.9). All these were detected by MRI. They were missed by CT in 6.3% (3.1-11.3). In all, 6.3% also had non-critical abnormalities that were reported only on CT. Cochlear dysmorphisms were more common in children but the overall frequency of abnormalities and their detection rates did not depend on age. Omitting CT and using MRI alone are estimated to miss no critical abnormalities (95% CI: 0-2.3 %).

CONCLUSIONS

While CT may be better at defining some abnormalities, MRI appears to be able to detect all abnormalities that are critical to patient management. Most candidates for cochlear implantation can therefore be assessed by MRI initially. CT is most likely to be helpful in those with a history of severe middle ear disease, meningitis, or dysmorphic syndromes, who should undergo both CT and MRI.

A rare cause of upper airway obstruction: spontaneous synchronous sublingual and laryngeal haematomas

Anticoagulation with warfarin is commonly used for prevention of thromboembolic events in patients with atrial fibrillation. Bleeding is the main side effect of anticoagulation. We report the case of a 66-year-old man who developed two spontaneous synchronous upper airway haematomas while on warfarin therapy. To our knowledge, this is the first reported case of a sublingual haematoma presenting simultaneously with supraglottic laryngeal haematomas. Upper airway haematomas are rare in the absence of a history of trauma but need to be urgently assessed due to their life-threatening potential. Clinicians should be aware of the possibility of haematomas involving the upper airway in patients on anticoagulant therapy, particularly if complaining of red flag symptoms such as acute onset dysphonia, odynophagia or airway/breathing difficulties.

Otitis externa

INTRODUCTION

Otitis externa is thought to affect 10% of people at some stage, and can present in acute, chronic, or necrotising forms. Otitis externa may be associated with eczema of the ear canal, and is more common in swimmers, humid environments, people with absence of ear wax or with narrow ear canals, hearing-aid users, and after mechanical trauma.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of empirical and prophylactic treatments for otitis externa? We searched: Medline, Embase, The Cochrane Library, and other important databases up to October 2007 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found nine systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review, we present information relating to the effectiveness and safety of the following interventions: oral antibiotics, specialist aural toilet, topical acetic acid drops or spray, topical aluminium acetate drops, topical antibacterials, topical antifungals, topical anti-infective agents, topical corticosteroids, and water exclusion.

Otitis externa

INTRODUCTION

Otitis externa is thought to affect 10% of people at some stage, and can present in acute, chronic, or necrotising forms. Otitis externa may be associated with eczema of the ear canal, and is more common in swimmers, humid environments, people with absence of ear wax or with narrow ear canals, hearing-aid users, and after mechanical trauma.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of empirical and prophylactic treatments for otitis externa? We searched: Medline, Embase, The Cochrane Library, and other important databases up to October 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found nine systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: oral antibiotics, specialist aural toilet, topical acetic acid drops or spray, topical aluminium acetate drops, topical antibacterials, topical antifungals, topical anti-infective agents, topical corticosteroids, and water exclusion.

An experimental comparison of handover methods

INTRODUCTION

With the increase in shift pattern work for junior doctors in the NHS, accurate handover of patient clinical information is of great importance. There is no published method that forms the gold standard of handover and there are large variations in practice. This study aims to compare the reliability of three different handover methods.

PATIENTS AND METHODS

We observed the handover of 12 simulated patients over five consecutive handover cycles between SHOs on a one-to-one basis. Three handover styles were used and a numerical scoring system assessed clinical information lost per handover cycle.

RESULTS

After five handover cycles, only 2.5% of patient information was retained using the verbal-only handover method, 85.5% was retained when using the using the verbal with note taking method and 99% was retained when a printed handout containing all patient information was used.

CONCLUSIONS

When patient information is handed over by the verbal only method, very few facts are retained; therefore, this method should be avoided whenever possible. Verbal handover with note taking is shown to be an effective method of handover in our study, although we accept that this is an artificial scenario and may not reflect the reality of a busy hospital. Nearly all information is retained by the printed handout method but this relies on the handout being regularly updated.

Sphenopalatine artery ligation: technical note

Epistaxis is a common problem. Most patients presenting to hospital will stop bleeding with simple first-aid measures or with nasal packing. Those who do not stop will usually require surgical management. For persistent posterior epistaxis, the sphenopalatine artery may be ligated as the artery leaves the sphenopalatine foramen to enter the nasal mucosa of the lateral wall of the nose. This may be performed endoscopically. We describe the anatomy of the area and the surgical technique. We also present a brief review of the literature on this technique.