No patient is untestable: A CVI Q&A with Dr. Barry Kran

A conversation with Dr. Kran on evaluating patients suspected of having CVI, diagnosing CVI, and his approach to working with children, no matter their complexities

Dr. Kran showing a Teller Acuity Card to his patient

CVI families know all too well how difficult medical visits can be. Sometimes parents leave with few answers about their child’s vision. As the medical community continues to become more aware of Cortical Visual Impairment/Cerebral Visual Impairment (CVI), we want to highlight the clinical practices of Dr. Barry Kran, Optometrist (OD), and how he evaluates children suspected of having CVI. He discusses his approach to working with children, no matter their complexities, and how his clinic is a bridge between the medical and education communities that serve his patients.

Dr. Kran is a professor at the New England College of Optometry and the Optometric Director of the NECO Center for Eye Care at Perkins.  His optometric colleagues at the clinic are Dr. Nicole Ross and Dr. Alicia Donahue, and they share a similar approach to care. The team is also privileged to have Dr. Luisa Mayer, PhD, a visual field specialist, with them on a part time basis.

Let’s start with who you are as a practitioner. You have a great statement in your chapter in Marc Taub’s book,Visual Diagnosis and Care of the Patient with Special Needs:

A patient is neither uncooperative nor untestable. It is the responsibility of the provider to create an environment where the patient can be successful.  Once the proper environment is created and trust built, it is typically possible to assess basic clinical information, such as acuity, and to also assess how the individual uses their vision. Adjusting how to engage a patient with a particular test, as well as adjusting the environment to determine impact on performance allows for not only the successful acquisition of data, but it also allows for observation regarding how the task and/or environment can impact the use of vision. 

How did you cultivate this philosophy of practice?

Before I came to the Perkins Low Vision Clinic in 2001, I had more of a general practice with an emphasis on working with individuals with binocular dysfunctions, and also worked with individuals with intellectual disabilities. The year prior to coming to Perkins, I worked in the pediatric ophthalmology practice at Tufts. Soon after joining the Low Vision Clinic, I knew that I needed to work differently to obtain information from this patient population. It was clear that patient care would be challenging and I was excited to see how it was going to unfold. I was fortunate to have an experienced vision educator, Darick Wright, with me and together we created an effective approach to patient care.

After a few months, a Perkins’ staff member from the Secondary Program commented on one of my reports where I noted that the patient was untestable or uncooperative. These are phrases that I had seen in eye care records over the years and didn't think an awful lot about it. This staff member said to me, “this was a wonderful report, and you were able to get more information from the patient than anyone else ever did.” She went to say, “I really don't think it's a fair representation to say that he was uncooperative. I think he was doing the best that he could have done.” 

This vignette still gives me goosebumps every time I tell it—it was a paradigm shift for me. Since that day, those words ceased to exist in our reports. And that's why in a lot of my lectures, I say that it's not the patient who’s uncooperative—it’s the doctor’s inability to adjust what they are doing to make it accessible for the patient. The caveat is doing the right test at the right time in the right way. This moment was the tipping point for me.

It's not the patient who’s uncooperative—it’s the doctor’s inability to adjust what they are doing to make it accessible for the patient. 

Describe your process for diagnosing a new patient with CVI.

There are some similarities, but it's almost as different as every presentation of CVI.

I look at the raw materials that we have going into the exam.

  • What’s the patient's medical history?
  • What's their birth history?
  • What was the pregnancy like?
  • What kind of reports do we have that provide additional information?
  • What has the ophthalmologist or optometrist found prior to this appointment?
  • What is all the information that vision specialists found working with the patient in early intervention or wherever the child is? 

So I look at the eye report, and read about their use of vision in their everyday lives. Does it make sense? Is it consistent? Is it not consistent? And if not, what do I need to consider during the evaluation? What kinds of questions do I need to ask during the history portion of the exam? There are often many other reports to synthesize as well, which might include the psychoeducational report, IEP, evaluations from providers, and other medical reports such as those from the neurologist.

As I review the history and ask questions with the family, I am also observing the patient.

  • Are they looking around?
  • Are they paying attention to the space around them? 
  • Are they only looking at someone when they speak?
  • Do they not look at anyone, whether they're speaking or not?
  • Are they just staring at the lights when someone is speaking to them? 

I'm taking in information visually by observing the kid, auditorily from all those present for the exam, plus the research ahead of time. 

And then we start working with the child with a sense of what might be the most important tests to be performed and to be able to pivot as information is obtained. The first step is figuring out how I can best relate to the patient, and how I best engage them in the exam. I have to be able to engage the patient to get their confidence because otherwise the data is useless. Did I find an actual visual threshold or did I lose their participation in the task? 

The first step is figuring out how I can best relate to the patient, and how I best engage them in the exam. I have to be able to engage the patient to get their confidence because otherwise the data is useless.

Dr. Kran holding a green translucent ball with a small light behind it in front of his patient

How do you measure acuity?

We start with measuring acuity with both eyes open because that’s how we live in the world. If certain behaviors are noted in the history with respect to head and/or eye position or movement, then we need to initially collect data in the most natural way possible. This would mean first assessing acuity with both eyes open.  And then, if they're not tactically defensive or we haven't stressed them out, we can go back and collect acuity one eye at a time. But the goal is to try to address the concerns that are there and then move forward. 

I don't have the pleasure of seeing my patients in their environments. I only have the opportunity to see them in the office. I play with the environment in the office to get a better sense of how the patient responds. For example, if I'm using Teller Acuity Cards (see image below), I might first present one with the room lights on while the interns in the room talk and see what the patient does. If they don’t respond, I'll turn off the lights, make sure everyone is quiet, present the card, use task lighting on the card and wait. Now that we've simplified the environment, all of a sudden, the patient may fixate and do so with less latency, and with increased visual attention. We might only get through a few cards before the patient needs a break, but this tells me something about how the environment impacts the use of vision. This allows me to make a strong statement about the impact of the environment on the child’s ability to access their learning. This should also be confirmed by vision educators. 

Nowadays a lot of practices have electronic screens with their acuity charts. And it's typically no longer the standard Snellen format [chart with 11 lines of letters in a range of sizes]. Depending upon the child’s history, there are times where I purposely will show multiple lines of letters on the computer screen and ask the patient to read. Then I'll switch to a single letter or a single line. Sometimes I go in the reverse order. If the patient seems anxious or nervous and needs a lot of positive affirmation, I'll probably start with a single letter presentation or a single symbol to see what the acuity is with both eyes open. Then I’ll show them the full chart and see what happens. If there's a very significant difference between those two findings, that to me is often a powerful indicator that CVI might be present.

Dr. Kran holding a Teller Acuity Card in front of his patient who is pointing to one side of the card.

What are the specific practices you do in your clinic to look for the visual behaviors of CVI?

I don't have an answer to that question because the visual behaviors tend to show themselves or the history reveals them. We create an environment where we can allow those visual behaviors to surface. I’ll sit with the patient and we’ll play with puzzles. Or to break the ice ahead of the exam, my interns work with the patient at the little table, playing with the LEA 3D puzzle. I’ll observe what the patient is doing. Is the patient placing the pieces without looking? Does the patient get more frustrated with a more complex puzzle? Is this something the parent sees at home? With the behaviors I see, I follow up and explore them. Careful history—which continues throughout the examination–and careful observation reveals quite a lot about our patients. 

Careful history—which continues throughout the examination–and careful observation reveals quite a lot about our patients.

How do you determine whether or not CVI is present?

We pay careful attention to how the patient uses their vision. A diagnosis is a constellation of things. It’s the homework we did before the exam, reviewing reports and the hard work during the exam. One of the survey tools I use is the TeachCVI survey as part of my information gathering from the families. At the end of the evaluation, the information is resynthesized, and a diagnosis is made. Then significant time is spent explaining the diagnosis and providing parental education and advocacy. All of this plus additional resources (as needed) are provided in the report that is produced within a week of seeing the patient.  

Is there anything that parents and educators can do before an appointment to better support the diagnostic process?

Yes, make absolutely sure we have all the reports. Ensure we have the IEP, educational evaluations, functional vision evaluations, neuro-psychological reports, SLP, OT and/or PT reports, as well as those from the appropriate medical providers including the neurologist, the physiatrist, and prior ones from the ophthalmologist and/or optometrist. If the child has seizures, it is helpful to know how controlled they are, and what precipitates them. EEG reports are also helpful to review. 

I try to set up a situation to make the parents feel comfortable. I’ll say, “We're going to be working with your child. We're usually really good at figuring out when somebody needs a break. If there's body language or something that we're missing or something that we're doing that's not going to work, feel free to help us make sure that it's successful.” So we try to engage the parents to show that we're all in it together. 

For children who have already been diagnosed with CVI, what does your clinical visit look like?

I will check in and find out what the parent is observing about their child’s visual behaviors. I would say, “Previously, you noted A, B, C and D. What are you noticing from your child now? Is the depth and breadth of these behaviors the same? Have you noticed some changes? In what environments have you noticed those changes? Do you see it across other environments? What new behaviors, if any, are you seeing that you're concerned about today?”

The parent may report that the vision teacher has been awesome and describes what the teacher is doing. But then say that their child is transitioning to a new school and are not sure if they will have the same vision teacher. I try to pay attention to things that I need to help advocate for to make sure that the patient continues to progress. My history taking will be a little different for a child who is already diagnosed with CVI. However, my exam will be very much the same, while I’m also looking to observe what the parents shared with me about their child’s behaviors. For example, if I go with something novel or set something up in a unique way for the child, do I see fall-back to those earlier behaviors? And then if I set something up in a different way, do the visual behaviors become more typical?

I try to pay attention to things that I need to help advocate for to make sure that the patient continues to progress.

Dr. Kran holding a light up spinner in front of the patient while placing a light to the left of the patient

How do you collaborate, and how do you see it benefiting your patients?

Our clinic bridges the gap between the medical eye community and education. The clinic provides parents the tools to bring to their child’s educational team or therapeutic team or whatever system they are working with at the time. Our hope is that the providers can pay attention to what we’ve observed in the clinic and think about what that means as they work with the child.

From a vision-function point of view, and from what we observe in the exam room, I’m able to state in the report what the diagnoses are and why some level of intervention (assessment and/or intervention) by the vision educators is necessary.  Further, if indicated, and until a more formal assessment can be completed, a starting point for print size is provided.  Advocacy for collaboration among all team members is also vitally important, especially for our patients with CVI. 

Thank you, Dr. Kran. Your clinical practices are changing lives for kids with CVI.

Well, thank you. The past 20 years have gone by quickly and the learning and challenges still remain, which is one of the things that still keep patient care exciting.  Working with families in this way is also very rewarding as one gets to see a child grow and maximize their potential—visually and otherwise.  

Want to learn more from Dr. Kran? Check out these resources: