What Is a RetCam and How Is the Exam Performed?

A RetCam is a wide-field digital fundus camera designed to photograph the inside of an infant’s eye, capturing up to 130 degrees of the retina in a single image. It is the most widely used device for screening premature babies for retinopathy of prematurity (ROP), a potentially blinding condition, and it also plays a role in documenting retinoblastoma, retinal hemorrhages from suspected abuse, and other pediatric eye diseases. The exam itself is brief but involves several specific steps, from dilating the pupil to placing a small camera probe directly on the eye’s surface, and it understandably raises questions for parents who have never seen anything like it.

What the Device Actually Looks Like and Does

The RetCam is a cart-mounted system with a monitor, a computer for storing images, and a hand-held camera probe. The probe is roughly the size of a large pen and has a small lens at its tip. Unlike the standard eye cameras adults sit in front of at an optometrist’s office, the RetCam is a contact camera: the lens physically touches the surface of the eye through a layer of clear coupling gel. This contact approach is what allows it to capture such a wide view of the retina, far more than a traditional desktop camera could manage.

The wide-angle view matters because many pediatric eye diseases do not confine themselves to the center of the retina. ROP, for instance, often begins in the far periphery where the retinal blood vessels are still developing. A conventional camera that only photographs the central 30 or 45 degrees would miss exactly the areas that matter most. The RetCam’s ability to image the retina out toward its edges in a single shot is a major reason it became the standard tool for neonatal eye screening. Handheld pediatric fundus cameras like the RetCam, along with newer devices such as the Phoenix ICON, have been especially valuable in countries where there are not enough trained specialists to examine every at-risk baby in person.¹

Step by Step Through the Exam

If your baby is scheduled for a RetCam exam, here is what typically happens. The process can look alarming if you are not prepared for it, but each step has a clear purpose and the whole session usually takes only a few minutes of active imaging.

First, the baby’s pupils are dilated with eye drops, the same kind of drops used when adults have a dilated eye exam but in lower concentrations appropriate for infants. This takes about 30 to 45 minutes to take full effect. While waiting, staff may swaddle the baby snugly and offer a pacifier dipped in a sucrose solution. These comfort measures are not just nice gestures: a randomized trial found that combining oral sucrose with a pacifier and swaddling significantly reduced pain scores during ROP screening, both at the point when the eyelid speculum was inserted and during scleral indentation.²

Once the pupils are fully dilated, a topical anesthetic drop is placed on each eye to numb the surface. The examiner then inserts a small eyelid speculum, a tiny spring-loaded clip that holds the lids open so the baby cannot blink during imaging. This is usually the step that looks most distressing to parents, though the anesthetic means the baby feels pressure rather than sharp pain.

With the lids held open, the examiner applies a clear coupling gel to the tip of the RetCam probe and gently places it against the eye’s surface. The probe is oriented in different directions to capture images of the central retina, the optic nerve, and each quadrant of the peripheral retina. In a typical screening session, five to seven images per eye are taken, covering the major zones where disease is most likely to appear. The examiner may gently rotate the baby’s head or reposition the probe to reach the far periphery. In some cases, a scleral depressor (a small, smooth instrument pressed against the outside of the eye through the lid) is used to bring the most distant retinal tissue into view.

After imaging, the speculum is removed, the coupling gel is wiped away, and the baby is re-swaddled and comforted. The entire hands-on portion, from speculum in to speculum out, often takes less than five minutes per eye, though it can feel longer to a watching parent.

Why the Exam Is Done

ROP screening is by far the most common reason a RetCam is used. Premature babies, particularly those born before 31 weeks of gestation or weighing less than about 1,500 grams at birth, are at risk for abnormal blood vessel growth in the retina. If caught early, the severe forms of ROP can be treated with laser therapy or anti-VEGF injections. If missed, the disease can progress to retinal detachment and permanent vision loss. Because the window for treatment is narrow and the stakes are high, screening programs have been built around the RetCam in neonatal intensive care units worldwide.

The device is also used to monitor children being treated for retinoblastoma, the most common eye cancer in children. After treatment with chemotherapy, laser, or cryotherapy, doctors use RetCam photographs and fluorescein angiography (injecting a fluorescent dye and photographing how it flows through the retinal blood vessels) to evaluate how the tumor and surrounding tissue are responding. One retrospective study found that wide-angle fluorescein angiography through the RetCam was useful for evaluating tumor-related vascular and retinal changes after treatment.³

A third important use is documenting retinal hemorrhages in cases of suspected abusive head trauma (sometimes called shaken baby syndrome). When an infant suffers inflicted head injury, the resulting retinal hemorrhages tend to be numerous, involve multiple layers of the retina, and spread all the way out to its edges.⁴ The RetCam’s wide-angle photography can capture and permanently record these findings in a way that a doctor’s hand-drawn sketch cannot, which matters when the images may be needed in legal proceedings. The RetCam is considered the gold standard for acquiring retinal images in suspected abuse cases, though combining it with optical coherence tomography (OCT) gives even more detailed information about small hemorrhages near the macula.⁵

How Accurate Is It Compared to a Traditional Eye Exam

The traditional method for examining a premature baby’s retina is binocular indirect ophthalmoscopy (BIO), where a specialist holds a bright light and a magnifying lens to look directly into the eye. BIO is considered the clinical reference standard, but it depends entirely on the skill and availability of the examiner, and it produces no permanent record of what was seen.

Multiple studies have compared RetCam imaging against BIO. In one study, digital photography through the RetCam had perfect sensitivity for detecting the stages of ROP that require treatment, meaning no cases of prethreshold or threshold disease were missed by the image reader. Specificity was about 97.5%, with a negative predictive value of 100%.⁶ Another comparison found that wide-field digital retinal imaging detected treatment-requiring ROP and plus disease (a severe form marked by abnormally dilated and tortuous blood vessels) with 100% sensitivity and 100% specificity, though it was less sensitive for early, mild ROP that did not yet need treatment.⁷

The practical takeaway is that RetCam imaging is extremely reliable for catching the disease that matters most: the stages severe enough to threaten vision. Where it can fall short is in picking up very early or mild disease, which makes sense given that subtle peripheral findings in a squirming infant can be hard to capture in a still photograph. For this reason, most programs use RetCam images as the primary screening tool but still rely on an ophthalmologist’s direct exam when the images raise concern or when clinical judgment calls for it.

Is the Exam Safe for Premature Babies

Parents often worry about whether the exam itself could harm a fragile premature infant. The evidence is reassuring overall, but the exam is not completely without transient effects. A large safety study found that the most common adverse events during ROP screening visits were brief episodes of apnea (paused breathing), slowed heart rate, and drops in oxygen levels, along with occasional rapid heart rate or spitting up. About 90% of the adverse events fell into these categories, and all of them resolved by the end of the procedures.⁸

There is also emerging evidence that non-contact retinal imaging (a newer approach where the camera does not touch the eye) produces fewer safety events than the traditional bedside exam. One study found that safety events occurred after less than 1% of non-contact imaging sessions compared to nearly 6% of clinical examinations, a statistically significant difference favoring imaging.⁹ The RetCam itself is a contact camera, so this comparison applies most directly to newer non-contact devices, but it highlights a general trend: imaging-based screening tends to be less physiologically stressful than a hands-on ophthalmoscopic exam that involves scleral depression and a bright handheld light held close to the baby’s face.

Infection Control and the RetCam Probe

Because the RetCam probe makes direct contact with the eye, proper disinfection between patients is critical. This is not a theoretical concern. A documented outbreak of adenovirus in a neonatal intensive care unit was linked to ROP examinations: infection occurred far more frequently in neonates who had undergone ROP exams than in those who had not. The RetCam had been disinfected between uses, but the disinfectant required a 30-minute contact time to be effective against adenovirus, and the investigators flagged this as a potential vulnerability in the workflow.¹⁰

Most units now follow strict reprocessing protocols that include high-level disinfection of the probe tip and any reusable accessories after each patient. The specific agent and contact time vary by institution, but the lesson from outbreaks is clear: disinfection shortcuts in a high-volume screening session can have real consequences. If you are a parent and want to ask the screening team what their protocol is, that is a perfectly reasonable question.

Telemedicine Screening With the RetCam

One of the most transformative uses of the RetCam is remote screening. In a typical telemedicine model, a trained technician or nurse at a community hospital captures the retinal images, which are then transmitted to an ROP specialist at a distant center for interpretation. This is especially valuable in regions where there simply are not enough pediatric ophthalmologists to visit every NICU in person.

The SUNDROP telemedicine program, which ran for six years, screened over 600 premature infants using remote RetCam imaging. When compared to bedside ophthalmoscopy, remote interpretation of the images had 100% sensitivity and nearly 100% specificity for detecting treatment-warranted ROP, with a negative predictive value of 100%.¹¹ A separate evaluation at two remote sites confirmed that telemedicine screening reliably detected referral-warranted disease, with no poor visual outcomes during the study period.¹²

The practical impact is significant. Without telemedicine, a baby born prematurely in a rural hospital might need to be transferred to a larger center just for an eye screening, or a specialist might need to fly in periodically, with the risk that disease progresses between visits. With a RetCam on-site and a trained imager, the baby can be screened on schedule and the images reviewed within hours by a specialist hundreds of miles away. It does not eliminate the need for specialists, but it stretches their reach considerably.

What Parents Can Expect and Ask

For many parents, the RetCam exam is one of the more visually distressing procedures their baby undergoes in the NICU, even though it is relatively brief and well tolerated physiologically. Seeing a speculum hold open a tiny eye while a probe is placed on its surface is not easy to watch. Knowing ahead of time what will happen and why helps.

Research into parental satisfaction found that parents whose babies were screened with wide-field retinal imaging rather than traditional ophthalmoscopy reported a better understanding of their child’s eye condition, likely because the digital images could be shown to them on a screen and explained in real time.¹³ With BIO, the doctor looks into the eye and describes what they see; with the RetCam, the parent can see the same photograph the doctor is interpreting. That visual transparency can ease anxiety and build trust, especially when a baby needs repeated screening sessions over weeks or months.

Questions worth asking the screening team include how many sessions your baby is likely to need (typically every one to two weeks until the retinal vessels have matured or treatment is complete), what comfort measures will be used during the exam, and whether the images will be stored for comparison across visits. The ability to compare images over time is one of the RetCam’s biggest advantages over a traditional exam, which relies on the examiner’s memory and notes.

Artificial Intelligence and Where the Technology Is Heading

The combination of standardized digital images and a large clinical need has made RetCam data a natural fit for artificial intelligence. Several research groups have developed deep learning algorithms that can automatically analyze RetCam photographs for signs of severe ROP, particularly plus disease, the vascular abnormality that signals the most urgent need for treatment. One such algorithm, called ROP.AI, demonstrated high sensitivity and a high negative predictive value for diagnosing plus disease automatically.¹⁴

An active area of work involves testing whether AI models trained on RetCam images perform well when applied to images from other cameras with different fields of view. One recent study assessed a RetCam-trained AI algorithm on images from the Phoenix ICON, a smaller and more portable camera with a narrower field of view, to see whether the model could still detect severe ROP reliably across different hardware.¹⁵ Cross-device generalization like this is an important step toward deploying AI screening in settings that may not have the specific camera the algorithm was originally trained on.

If AI screening matures enough for clinical deployment, it could further reduce the bottleneck of specialist availability. A technician could image the baby, the software could flag any eyes that need specialist review, and the specialist’s time would be focused on interpreting borderline or positive cases rather than reviewing hundreds of normal exams. That pipeline already exists in prototype form in some telemedicine programs. It is not a replacement for expert judgment in complex cases, but for the straightforward binary question of whether a baby’s screening images look normal or not, the early results suggest AI can handle the workload accurately.