CARE MEDICINE SURGERY
Guided Procedure as Day Care
The value of interventional
procedures for expeditious and cost effective management of patient is widely
accepted. The use of CT guided procedures is wide spread along with fluoroscopic
and USG guided procedure.
A variety of instrument and approaches are used in different organs. The ability
to localise the needle tip consistently and accurately in an axial plane is
a distinct advantage of CT over fluoroscopy or USG.
It is possible to choose appropriate path to avoid structure including blood
vessels or bowel. A large variety of instrument ranging in size from 23 gauge
Chiba needle to 14 gauge trucut needles can be used.
Disadvantages are quite minimal compared to the advantages. These include cost,
radiation and availability of equipment.
Indications for CT guided procedure vary from institution to institution. Important
factors to consider are the visibility of the lesion on CT compared to other
modalities, the type of pathological sample required and location of the lesions.
Generally, anatomical areas such as lung, retro-peritoneum and pelvis are in
most instances best suited for CT guidance. When lesions are small, varying
and located in critical area, CT is the preferred method.
Critical areas that are best suited to CT puncture include abnormalities adjacent
to major vessels, hilum of spleen and mediastinum.
When a large cutting needle biopsy is indicated, CT is the modality of choice.
CT guidance makes it possible to biopsy more difficult lung lesion, to biopsy
mediastinum and use cutting needle safely in selected cases. CT is indicated
for a variety of lung lesions including those not well suited for fluoroscopy
or USG because of their location and additional factors. Lesion in the apices,
the costophrenic angle, pleural, hilar and mediastinum are best suited for CT.
Peripheral nodule and parenchymal lesions, associated with atelectasis and pleural
effusion, are well suited for CT.
Liver biopsy is a common CT procedure especially for focal mass lesions (with
the advent of dynamic bolus injection for liver lesion). Cutting needles have
become a routine procedure under CT guidance.
Percutaneous procedureas of the pancreas is widely accepted as the method of
choice for diagnosis of pancreatic masses. Aspiration of pseudocyst is easily
performed. Retroperitoneal masses, including neoplasm and nodal masses are approached
typically posteriorly, adjusted to the location of the kidney, major vessels
and bowel organ. CT biopsies of the kidneys are performed for either evaluation
of masses or sampling of diffuse parenchymal disease. In a patient, with malignant
or infectious process in an adrenal mass, aspiration should be performed, if
confirmation of the process will change management of the patient. Small aspiration
needle are used to avoid possibility of penetrating a loop of bowel while attempting
biopsy for mesenteric masses.
Pelvis is a frequent candidate for biopsy by CT guidance including metastatic
tumour from colon, bladder and prostate and other organs.
CT can be used readily for performing a number of aspirations and drainage in
different portions of the body, mostly abscesses, but, occasional cysts, lymphocoeles,
pseudocyst biloma, etc.; bone biopsies and CT guided biopsy for soft tissue
musculature are also performed routinely.
Sinogram and drainage catheter placement and percutaneous nephrostomy placement,
stereotaxic biopsy for brain tumour, can be performed under CT guidance. Newer
exciting areas of interventional radiology include, CT guided nerve blocks (pain
management) and alcohol ablations.
Most of the procedures under CT guidance are being performed as Day Care. Therefore,
Day Care CT guided procedures are possible, economical and convenient to the
patient and medical care providers.
( Dept. of Radiology, Bombay Hospital Institute of Medical Sciences, Mumbai)