Our Summary

This study looked at how effective a type of imaging known as a low-radiation dose CT scan is at diagnosing a condition called vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO). This condition, which causes difficulty breathing, can often be mistaken for or occur alongside severe asthma. The current standard method of diagnosing it is through laryngoscopy, which involves using a small camera to look directly at the vocal cords.

To test the effectiveness of CT scans, researchers performed both laryngoscopy and CT scans on two groups of patients: one group had the procedures done an hour apart, while the other group had them done 4-6 weeks apart. The researchers then compared the results of the two methods.

In the first group, the CT scan method correctly identified VCD/ILO in about 54% of cases (sensitivity), and correctly identified individuals without the condition in about 89% of cases (specificity). In the second group, the sensitivity was about 76% and the specificity was about 93%.

When the researchers assumed that about 30% of the people coming to their clinic had VCD/ILO, the CT scan method was able to correctly rule out the condition in more than 80% of both groups. However, the ability of the CT scan to correctly identify the condition (positive predictive value) varied between the two groups.

In short, this study found that low-radiation dose CT scans could potentially be an alternative method for diagnosing VCD/ILO. However, the performance of this method varied between the two groups, suggesting that more research is needed. The study was supported by the Monash Lung and Sleep Institute and others.

FAQs

  1. What is the current standard method for diagnosing vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO)?
  2. How effective were low-radiation dose CT scans in diagnosing VCD/ILO based on the study?
  3. Could low-radiation dose CT scans be an alternative method for diagnosing VCD/ILO?

Doctor’s Tip

A helpful tip a doctor might tell a patient about vocal cord surgery is to follow all pre-operative and post-operative instructions provided by their healthcare team. This may include avoiding smoking, resting the voice, staying hydrated, and attending follow-up appointments for monitoring recovery progress. It is important to communicate any concerns or changes in symptoms to your healthcare provider to ensure the best possible outcome after vocal cord surgery.

Suitable For

Patients who are experiencing difficulty breathing and are suspected of having vocal cord dysfunction/inducible laryngeal obstruction (VCD/ILO) are typically recommended vocal cord surgery. This condition can often be mistaken for or occur alongside severe asthma, so accurate diagnosis is crucial for determining the most appropriate treatment plan. In some cases, a low-radiation dose CT scan may be used as an alternative method for diagnosing VCD/ILO, as demonstrated in the study discussed above. However, further research is needed to fully understand the effectiveness of this imaging technique in diagnosing and treating this condition.

Timeline

Before vocal cord surgery:

  1. Patient experiences symptoms such as hoarseness, difficulty breathing, or voice changes.
  2. Patient consults with an ear, nose, and throat (ENT) specialist who may recommend laryngoscopy to diagnose the issue.
  3. If VCD/ILO is suspected, the patient may undergo a low-radiation dose CT scan to further evaluate the vocal cords.
  4. Based on the diagnosis, the ENT specialist may recommend vocal cord surgery to treat the condition.

After vocal cord surgery:

  1. Patient undergoes vocal cord surgery to correct the issue causing the symptoms.
  2. Recovery period following surgery, which may include voice rest and restrictions on certain activities.
  3. Patient may undergo speech therapy to help with vocal cord rehabilitation and improve voice quality.
  4. Follow-up appointments with the ENT specialist to monitor healing and assess the effectiveness of the surgery.

What to Ask Your Doctor

Some questions a patient should ask their doctor about vocal cord surgery include:

  1. What specific type of vocal cord surgery do you recommend for my condition?
  2. What are the potential risks and complications associated with vocal cord surgery?
  3. How long is the recovery period after vocal cord surgery?
  4. What are the expected outcomes and success rates of vocal cord surgery for my condition?
  5. Are there any alternative treatments or therapies that I should consider before opting for surgery?
  6. Will I need to undergo any additional tests or evaluations before the surgery?
  7. How experienced are you in performing vocal cord surgery, and what is your success rate?
  8. What type of anesthesia will be used during the surgery, and are there any risks associated with it?
  9. How soon after the surgery will I be able to speak normally and resume normal activities?
  10. Are there any specific post-operative care instructions or lifestyle changes that I should follow to ensure a successful recovery?

Reference

Authors: Koh JH, Ruane LE, Phyland D, Hamza K, Fukusho R, Leahy E, Avram A, Yap G, Lau KK, MacDonald MI, Leong P, Baxter M, Bardin PG. Journal: NEJM Evid. 2023 Jan;2(1):EVIDoa2200183. doi: 10.1056/EVIDoa2200183. Epub 2022 Dec 22. PMID: 38320086