As an integral part of the NNI, the Neuroradiology Department serves to provide a subspecialised neuroradiology service not only to the inpatients and outpatients of NNI and Tan Tock Seng Hospital (TTSH) but also to referrals from private clinics and other hospitals.

This Department is equipped with a wide range of advanced neuro-imaging equipment, all dedicated to producing high quality images of the brain and spine.

Computed Tomography (CT) Scan

CT is a specialised examination using a combination of x-rays and computer technology to produce cross-sectional images of the head and spine, allowing for better diagnosis. The Department operates a 24-hour CT service to cater to both inpatients and outpatients. Currently, there are two CT scanners, one single slice and one multi-slice scanner. Both are capable of producing detailed 3D reconstruction of complex cranial abnormalities and facial. Accurate rendering of the bony structures of the head and spine can now be achieved in minutes, with advanced processing protocols. For patients with conditions that require biopsies, CT guidance can be used to allow greater accuracy in obtaining tissue samples.

Magnetic Resonance Imaging (MRI)

The MRI is a diagnostic tool that utilises strong magnetic field and radio frequency waves to create images of the body. No X-rays or radioactivity is involved. The magnetism and radio frequency are safe as they cause no known biological harm to cells or chromosomes at the current strength. The department operates two MRI scanners. The first has a high field 1.5 Tesla superconducting and the second has a 3.0 Tesla superconducting magnet. The 3T scanner has double the magnetic strength of a 1.5T MRI system. This results in significantly higher signal-to-noise ratio which allows for more accurate imaging and clearer depiction of the blood vessels of the brain. It is especially useful in patients with stroke, brain tumours and epilepsy. In addition to fast and accurate clinical imaging, the machine is also able to perform functional MRI (fMRI) and proton spectroscopy. The fMRI studies can be done in real time, thus enabling the result to be known immediately and obviating the need for repeat studies. Cerebrospinal fluid flow (CSF) studies are regularly done in addition to the routine scanning of patients with headaches, giddiness and stroke or transient ischaemic attacks (TIA). The availability of advanced imaging techniques such as diffusion and perfusion imaging has greatly improved diagnostic workshop of complex neurological conditions. Pre surgical localisation of brain tumours and other lesions is carried out regularly. These stereotactic procedures enable the surgeon to precisely locate the lesion during the operation.

Angiography

An angiogram is a specialised x-ray examination of the blood vessels of the brain and other parts of the body. Angiography entails an injection of contrast medium to outline the blood vessels to render them "visible" in the x-ray images. This is done through a small tube inserted in the groin. The angiographic unit in the Department is a bi-plane Digital Subtraction Angiography (DSA) machine specifically designed for optimal imaging of the blood vessels in the brain and spine. It produces fast rotational angiography and is able to perform 3-D angiographic images. In addition to diagnostic cerebral and spinal angiograms, the Department has an active interventional neuroradiology service enhanced by the availability of bi-plane flouroscopy and accurate road mapping. It has a very active interventional neuroradiology service. Embolisation of brain and spine arteriovenous malformations (AVM), dural arteriovenous fistulas (DAVF), coil packing of aneurysms and pre-operative devascularisation of head and neck tumours are some of the routine procedures carried out in the unit. Further information on coil treatment of brain aneurysms is available here. The Department also offers outpatient cerebral angiography as a routine service. Compared to the previous 2-day hospital stay required for such a procedure, the patient only needs to report to the department in the morning and is discharged on the evening of the same day. Nowadays, only the elderly and those with significant medical problems require inpatient stay for diagnostic cerebral angiography.

Interventional Neuroradiology

Interventional Neuroradiology is the technique used to treat blood vessel diseases, tumours, clots, etc. in the brain and spinal canal through small tubes ("catheters") inserted into the groin artery of a patient, much like an angiography procedure but the tube is much finer (called a "microcatheter") travels further, often right to the point of the diseased artery or vein itself. After an angiogram showing the abnormality in the blood vessels, a "road map" of the blood vessels is obtained, allowing precise placement of microcatheters deep into the brain or spinal cord close to the site of the disease. Under x-ray guidance, the appropriate treatment is then carried out according to the exact nature of the disease. Types of cases performed in Neuroradiology: The following diseases in the brain, spine and head, face & neck regions can be treated by interventional neuroradiology either as the sole form of therapy or combined with other treatment methods (such as surgery or radiosurgery): Aneurysm. Arteriovenous malformation (AVM). Excessive bleeding in the head, face and neck region. Spasm of brain artery. Carotid cavernous fistula (also known as caroticocavernous fistula). Brain tumour a)  to reduce the blood supply prior to surgery.  b)  to do a balloon test blockage of brain artery to check if it can be tied off at surgery. Certain pituitary tumours - to obtain a sample of blood from veins deep inside the brain to check hormone levels prior to surgery (cavernous/inferior petrosal vein sampling). Stenosis of major brain artery (eg. Carotid angioplasty and stenting, Vertebral angioplasty and stenting). Interventional Neuroradiology Equipment in NNI: NNI is equipped with a dual plane angiographic system with road mapping facilities. When it was installed in June 1999, it was the first machine in South East Asia with dual plane angiography and 3D angiographic reconstruction capability. This allows the operator to simultaneously view the blood vessels live at two different angles during the procedure, a very important feature in the treatment of brain aneurysms, arteriovenous malformations and carotid cavernous fistulas. In the second half of 2008, the angiographic machine is scheduled to be replaced by a new dual plane, flat panel, fully digital angiographic unit with built in capability to obtain CT images. This will help NNI enhance even further the performance of these delicate procedures and ultimately improve the safety of our patients. In carrying out these types of sophisticated interventional neuroradiology procedures, it is important to have an adequate inventory of embolisation and salvage equipment in case complications arise. The department is fully equipped with microcatheters, micro guide wires, balloon catheters, microballoons, microstents, microsnares, etc., together with embolic materials such as glue (N Butyl Cyanoacrylate "NBCA" glue and Onyx glue), particles (Polyvinyl Alcohol "PVA", Gelfoam), detachable coils (Guglielmi Detachable Coils "GDC", Microventiona Hydrocoils, compass and multiplex coils), detachable balloons (Ingenor and Balt latex balloons). The procedure room has general anaesthetic equipment and patient monitoring equipment and is also stocked with life saving important medical drugs such as nimodipine, tissue plasminogen activator (tPA), tirofibran, etc., needed in the treatment of clots in the brain arteries and veins and vessel spasm. For non-Singaporean patients who require help in arranging for medical therapy at the NNI, please click here.

Nuclear Medicine Imaging

The nuclear medicine scanner completes the range of neuro-imaging equipment available at the Institute. This is a dual head gamma camera that is able to perform radioisotope brain scans as well as general nuclear medicine imaging, including bone scans, cardiac scans, lung scans and renal scans. The nuclear medicine procedures carried out in the Department are reported by visiting consultants from the Department of Nuclear Medicine, Singapore General Hospital. Cardiac perfusion (MIBI) radioisotope scans are conducted once a week and are reported by a consultant cardiologist.

Request for Services Radiological requests must be made through a doctor in the form of a memo or on a Radiological Request Form provided by the Department. Location Department of Neuroradiology (Basement 1) National Neuroscience Institute 11 Jalan Tan Tock Seng Singapore 308433 Appointment & Referrals Hotline:      (65) 6357-7022 / (65) 9686-4700 (8:30 am to 5:30 pm) Telephone: (65) 6357-7041 / (65) 6357-7042 (24-Hour) Facsimile:  (65) 6357-7039 / (65) 6357-7044 For more information about services of Neuroradiology Department, please click here

   Department of Neuroradiology
   NNI @ TTSH Campus

Staff Members	Sub-Specialty
Head & Senior Consultant
Dr Francis HUI Kim Hoong MBBS, FRCR (UK), FAMS	Interventional Neuroradiology
Senior Consultant
Dr Tchoyoson LIM Choie Cheio MBBS, FRCR (UK), M Med (Diagnostic Rad)	Diagnostic Neuroradiology
Dr SITOH Yih Yian MBBS, FRCR (UK), FAMS	Diagnostic Neuroradiology
Consultant
Dr Wickly LEE MBBS, FRCR (UK), M Med (Diagnostic Rad)	Interventional Neuroradiology