Allergy, Nose & Sinus

Headaches in the forehead region after sinus surgery – What could be the cause? (WARNING – GRAPHIC SURGICAL IMAGES & VIDEOS)

February 10, 2020

I recently saw a patient, Madam A, who had sinus surgery done by another surgeon for frequent sinus infections (recurrent sinusitis). She used to suffer from 4-5 episodes of sinus infections a year over the last few years. About a month after her sinus surgery, she started getting headaches in her left forehead region, just above her left eyebrow. She never had this pain prior to her sinus surgery. A review of the CT scan of her sinuses (special X-rays of her sinuses) before she underwent surgery showed that her sinus drainage pathways in both her cheek regions (maxillary sinuses) may be congested, predisposing her to frequent sinus infection. However, her forehead sinus (frontal sinus) was not affected.



Clear Left Frontal Sinus

A front view of the CT scan of Madam A’s sinuses showing a clear (black part indicating the sinus is filled with air) frontal sinus before her first sinus surgery



On examination, a nasoendoscopy (scope through the nose) showed that her cheek sinuses (maxillary sinuses) were open and clean. However, there was some scarring close to the drainage pathway of her left frontal sinus region. A repeat CT scan of her sinuses showed a complete blockage of her left frontal sinus, causing her to have constant left frontal headaches. A course of oral antibiotics, nasal wash and nasal steroid sprays did not alleviate her symptoms.



CT scan

A repeat CT scan of Madam A’s sinuses showing a blocked left frontal sinus (grey part) after her sinus surgery



Blocked Left Frontal Sinus

A CT scan showing the side view of Madam A’s sinuses. The left frontal sinus is completely filled with mucous (grey part)



Madam A underwent revision functional endoscopic sinus surgery (re-do sinus surgery) to unblock her left frontal sinus. The surgery was performed with Image Guidance System (IGS). IGS allows the surgeon to determine the exact position of the surgical instrument during sinus surgery.  The position of the surgical instrument is indicated by a green cross and superimposed on the CT scan images (refer to images below). This is especially useful in revision sinus surgery where by scarring or loss of surgical landmarks caused by previous surgery may make it difficult for the operating surgeon. Another good use of IGS is in patients with complex sinus anatomy (especially in the frontal recess). During Madan A’s sinus surgery, there was thick mucous encountered in the left frontal sinus. The frontal sinus pathway was widened and flushed with normal saline.  Post surgery, Madam A is glad that the headaches in the forehead region has resolved.





Revision Sinus Surgery

IGS images showing the position of the surgical instrument (suction tube) in the frontal recess where the mucous is suctioned out



IGS images showing the tip of the surgical instrument in the left frontal sinus



The extent of sinus surgery is often determined by a combination of patient’s symptoms and the severity of the sinus disease on a CT scan. One of the potential complication of sinus surgery is scarring, which can block off previously unaffected sinuses. Although uncommon, it is a potentially serious and debilitating complication like in Madam A’s case. Hence, it is important for the sinus surgeon to be meticulous during sinus surgery to avoid such a complication.



Best wishes,


Dr Gan Eng Cern
ENT Specialist Singapore

When Should You See An ENT Specialist In Singapore?

  • Any Ear, Nose or Throat symptoms that you are troubled with or concerned of
  • Persistent blocked nose with mouth breathing or snoring

Dr Gan Eng Cern

Dr Gan Eng Cern is a fellowship trained Consultant Ear, Nose & Throat (ENT) Surgeon. He completed his ENT training in Singapore and obtained his subspecialty training in Rhinology and Endoscopic Skull Base Surgery at the world renowned St Paul’s Sinus Centre, University of British Columbia, Vancouver, Canada. He was also a Senior Clinical Lecturer at Yong Loo Lin School of Medicine at the National University of Singapore. Dr Gan was an avid researcher with numerous publications in reputable international ENT journals. He was also an invited speaker and surgical dissection teacher in many ENT conferences and courses.


  • 2020 – Reader’s Choice Gold Award for Best ENT Specialist
    (Expat Living Singapore)
  • 2016 – Best Educator Award (Eastern Health Alliance)
  • 2016 – “Wow” Award (Patient Compliment)
  • 2014 – Eastern Health Alliance Caring Award – Silver
  • 2014 – 19th Yahya Cohen Memorial Lectureship (awarded by the College
    of Surgeons, Academy of Medicine Singapore for best scientific surgical
  • 2012 – Human Manpower Development Award (Ministry of Health,
  • 2007 – Singhealth Best Doctor Award


  • MBBS - Bachelor of Science, Bachelor of Medicine, Bachelor of Surgery (University of New South Wales, Sydney, Australia)
  • MRCS (Edin) - Member of the Royal College of Surgeons Edinburgh, United Kingdom
  • MMed (ORL) - Master of Medicine in ENT (National University of Singapore)
  • FAMS - Fellow of the Academy of Medicine Singapore

Why Choose Dr Gan Eng Cern


Reliable & Reputable ENT Expert

Experienced and patient ENT Specialist who has your best interests at heart. We aim to provide you with accessible and specialized care for any ENT condition in a comfortable setting.


Friendly & Helpful Clinic Staff

Our friendly staff will assist you to the best of our ability and we are happy to accept most insurance providers and assist with E-filing with relevant insurance providers or Medisave.


Advanced ENT Equipment & Fully Equipped Facility

Our ENT Specialist, Dr Gan Eng Cern, will be able to diagnose and offer personalised treatments for your specific ENT condition. You can expect a high level of ENT care in a spacious setting with in-house minor surgical, endoscopy, allergy testing and microscopy services.


Financial Options

There are various financial options available for you to ensure that you are able to receive the most optimal treatment and care. Our ENT clinic staff will be able to assist you with your medical insurance claims and work with your chosen healthcare organization to minimize the hassle and paperwork required. In some cases, you may be able to utilise the funds in your Medisave account to defray part of the costs of your treatment. As our clinic is accredited by the Medisave board, we are able to process your claims from your Medisave for certain clinic procedures.

Our ENT Clinic

  • clinic_img
  • clinic_img
  • clinic_img
  • clinic_img
  • clinic_img
  • clinic_img
  • clinic_img
  • clinic_img

Our Location

Make An Enquiry

Fill up the form and our clinic staff will get back to you within a few hours!

Prefer Whatsapp? Message us directly to book an appointment with our Dr Gan.

Dr Gan’s Blog

Read some of our latest articles about Ear, Nose and Throat ( ENT ) Health.