Double Maddox rods are used in dissimilar image test that is used to assess ocular alignment. It can indicate the amount of torsion (twisting of the images) the patient has. It is composed of cylindrical rods that create a perpendicular line to the axes of the Maddox rods by using a light source.

Disposable microkeratome blades are typically used to cut corneal tissue. It is typically used to make a corneal flap during laser assisted in-situ keratomileusis (LASIK). These blades are driven across the cornea either in a straight line or arcuate fashion either manually or via a motor.

Diagnostic penlight is easy to use and affordable. The pre-focused pinpoint lens directly illuminates eyes, ears, and throat. Activation is made simple by depressing the pocket clip. These penlights are available with a convienient pupil gauge on the side.

Digital ophthalmoscope is act as an illuminated microscope for the eye. It is used to examine the eye. Its use is crucial in determining the health of the retina and the vitreous humor. It uses a combination of specialist lens digital imaging and lighting technology, which allows capturing and recording a high quality digital image. It may also provide eyecare practitioners with a hand-held eye disease diagnostic device equal to that of hospital-based eye diagnosis cameras and provide them with the ability to e-mail detailed patient eye maps for consultations.

Direct gonioscope is a transparent device placed directly on the cornea along with lubricating fluid, to avoid damaging its surface. It is made of clear plastic and is dome shaped. It has a steeper external curvature than the cornea, such that the critical angle is not exceeded. Therefore, light rays originating from the angle are allowed to escape and can be observed from the side.

Dural substitute is designed for the repair of the dura mater. It is a collagen-based material that is treated with the proprietary no-react process. The no-react process reduces the body's inflammatory response to the implant, prolongs its durability and eliminates the need for rinsing prior to implantation.

Demineralized bone matrix is a composite of collagenous and noncollagenous proteins that contain bone growth factors. It may serve as both a bone graft enhancer and expander in spinal fusions. The osteoinductive potential of demineralized bone matrix is related to the presence of several osteoinductive proteins and growth factors, such as bone morphogenetic protein and transforming growth factor.

Deep brain stimulators consist of three components: the implanted pulse generator, the lead, and the extension. The implanted pulse generator is a battery powered neurostimulator encased in a titanium housing, which sends electrical pulses to the brain to interfere with neural activity at the target site. The lead is a coiled wire insulated in polyurethane with four platinum iridium electrodes and is placed in one of three areas of the brain. The lead is connected to the IPG by the extension, an insulated wire that runs from the head, down the side of the neck, behind the ear to the IPG, which is placed subcutaneously below the clavicle or in some cases, the abdomen. The IPG can be calibrated by a neurologist, nurse or trained technician to optimize symptom suppression and control side effects.

Disc replacement is an artificial disc that is implanted into the spine to imitate the functions of a normal disc. It is the soft cushioning structure located between the individual bones of the spine, called vertebra. It is made of cartilage-like tissue and consists of an outer portion, called the annulus, and an inner portion, called the nucleus. In most cases, the disc is flexible enough to allow the spine to bend.

DHEA-S is the sulfated version of DHEA. It is the most abundent steroid product of the adrenal glands. DHEA is rapidly converted to DHEAS by an enzyme present in the adrenals, liver and small intestine. It is present at concentrations greater than 200 times that of DHEA and has a longer half-life, which largely removes the diurnal variation.

Diagnostic angiography is an X-ray exam of the arteries, which is used to diagnose blockages or other abnormalities of the blood vessels. The objective of the exam is to define the site and extent of the arterial abnormality, allowing the physician to determine the best treatment options, and often allowing the treatment to be performed by the interventional radiologist at the same time.

Directional atherectomy is useful in the treatment of peripheral vascular occlusive disease. It can be used to treat many types of blockages in large arteries. It may be useful in treating eccentric blockages that are located on one side of the artery or blockages at a branch point in the artery.

Dual chamber (Biventricular) ICD is an electronic device that constantly monitors the heart rate and rhythm. When it detects a very fast, abnormal heart rhythm, it delivers energy to the heart muscle. This causes the heart to beat in a normal rhythm again. It has two leads that monitor the right atrium and the right ventricle. It can defibrillate the ventricle, and pace both the atrium and the ventricle in atrio-ventricular synchrony.

Digital imaging system is a sensitive and cost-effective means for detecting retinopathy. Its software and connectivity allows users to capture and manipulate images from a range of clincial instruments, and then integrate images and results into their practice management systems. It can capture and store images as single exam, sequence of exams or a video sequence.

Dynamic external fixator is a device used for dynamic external fixation of a distal fracture of the radius having a proximal leg fixed to the radius and a distal leg fixed to the metacarpal using fixation pins. The proximal and distal legs of the external fixator are connected by a hinge mechanism, which defines a range of flexion and extension of the wrist, and a track-track housing mechanism, which defines a range of radial and ulnar deviation of the wrist.

Digoxin is a cardiac glycoside that helps a weakened heart to function properly. Digoxin increases the strength of the heart muscle, helps to maintain a normal heart rhythm and helps to remove excess water from the body. Digoxin relieves symptoms of congestive heart failure, a condition that reduces the ability of the heart to pump enough blood through the body. Digoxin is used in atrial flutter and fibrillation because it reduces conduction through the AV node.

Dot & Slot Blotters features simple construction, four sample configurations and alphanumeric sample identification. These are used for DNA or RNA hybridizations and for protein immunological studies. Its application include clone screening with DNA/RNA probes and immunological screening with antibodies.

Dispensing Systems consist of a dispensing unit and a separate pump/controller with keypad. Dispensers are operated by remote computer using the controller's RS 232 port.