A Patent of Selection for a Jacketed Cardiac Stent

Hi, this is Rabbi, Dr. Yosef Freedland, Surgeon, and Patent Attorney on Medical Devices at Appelfeld Zer Fisher.

Let’s get down to some specific medical devices, for example cardiac stents, and how to write a patent on an invention in crowded terrain.

Before continuing, I must apologize to Ze’ev Fisher, of Appelfeld Zer Fisher, for writing this Blog in several posts; which is not the way Ze’ev Fisher prefers. However, this is the only way to go, in my humble opinion, in order to provide appropriate background related to the heart.

C’mon Ze’ev, have a heart.

Stent Background

Everybody, besides people in Kazakhstan like Borat Sagdiyev, are aware about stents.

For the sake of Borat, we will examine a bit about stents and specifically Cardiac Stents.

A stent is a mesh in a tubular configuration that is expanded in a hollow passage to open up an area that is blocked, usually by tissue. Cardiac stents are expanded in a heart artery to open up a partially blocked area of the artery.

The expanded stent forms a conduit through the blocked area of the artery so that blood flows relatively unimpeded.

There are two major types of cardiac stents as of this post: bare metal stents and jacketed stents.


Bare metal stents have a tendency to allow tissue to grow between the holes in the metal mesh. When there is a lot of tissue growing “up through the cracks”, meaning through the holes in the stent, the blood vessel may become blocked again; referred to as restenosis.

Jacketed stents include a tubular stent frame covered by a jacket. The jacket often comprises a dense mesh of polymer fibers which prevents tissue from growing between the large holes in the stent frame.

Jacketed stents usually prevent restenosis but result in other problems.

Any stent, whether bare metal or jacketed, gets coated on the inside surface with a flat layer of tissue cells soon after installation.

These tissue cells, referred to as endothelial cells, can break away from the polymer fibers. Mobilized endothelial cells attract platelets, and form a large clump of dangerous cells, referred to as an embolism.

An embolism is a very nasty creature that can lodge in a blood vessel that feeds an organ with nourishment from blood and cause a portion of organ tissue to die.

Up to 2% of all jacketed stents eventually result in necrosis of vital organs as a result of mobilized endothelial cells that have formed into an embolism.

It is not very good to have dead tissue in an organ, particularly in the brain where the dead tissue causes a stroke. Then again, an embolism isn’t very good when it lodges in the heart, kidneys, or lungs, either. So the best idea is to stay away from things that can cause an embolism.

No Good Options

And this doesn’t leave a stent recipient with many good options: If you opt for a bare metal stent, you can get a re-blockage of the vessel.

If you opt for a jacketed stent, you can end up with a stroke (or worse). Come on guys what to do?

OK, so this is Rabbi, Dr. Yosef Freedland, Surgeon, and Patent Attorney signing off just before we finish explaining how bad the problem is that YOU are going to solve.


February 9, 2009 at 3:49 pm 1 comment

Basic Principles of Patent Drafting – Summary

Greetings inventors, investors, patent drafters and anyone interested in patents! This is Rabbi, Dr. Yosef Freedland, surgeon, and patent attorney; leader of the medical device team Appelfeld Zer Fisher writing to you from the beautiful border of Ramat Gan, at the border of Bene Brak.

Getting back to your invention of the ultrasound probe that finds foreign bodies in people:

Alternatively, you have other suspicions about this fetal ultrasound probe. You suspect that even if the fetal ultrasound probe beams can be focused, the beams are limited to focusing at a maximum distance that is greater than your foreign body ultrasound probe.

Other ways to handle an unknown invention such as the fetal ultrasound probe is to add description and claims about how your invention can be focused to reflect off one object at a very short range and then modified to focus of a second object at a longer-range.

So in summary you write claims starting with the slug and then developing claims to the snail shell. you hope for the best, meaning that the first claim in its broadest form remains unchallenged. However you prepare for the worst meaning that you make plenty of backup claims supported by detailed description. With this hard shell protection, you are provided with multiple back up positions to allow us to protect your wonderful invention using items that are part and parcel your patent application, just like the snail shell that is part and parcel of a snail slug. So that winds it up for snails.

February 5, 2009 at 9:18 am Leave a comment

The Importance of a Broad Specification With Many Variations

Greetings inventors, investors, patent drafters and anyone interested in patents! This is Rabbi, Dr. Yosef Freedland, surgeon, and patent attorney; leader of the medical device team Appelfeld Zer Fisher writing to you from the beautiful border of Ramat Gan, at the border of Bene Brak. Before we get into snails, we’ll consider something faster, a 2009 Bugatti Veyron 16.4

A hip young man goes out and buys the best car available: a 2009 Bugatti Veyron 16.4. It is the best and most expensive car in the world, and it sets him back $1.24M. He takes it out for a spin and, while doing so, stops for a red light. An old man on a moped (both looking about 90 years old) pulls up next to him. The old man looks over the sleek, shiny surface of the car and asks, “What kind of car ya’ got there, sonny?”

The young man replies “A 2009 Bugatti Veyron 16.4. It cost $1.24M.”

“That’s a lot of money” says the old man, shocked. “Why does it cost so much?”

“Because this car can do up to 320 miles an hour!” states the cool dude proudly.
The moped driver asks, “Can I take a look inside?”  “Sure,” replies the owner.

So, the old man pokes his head in the window and looks around. Leaning back on his moped, the old man says, “That’s a pretty nice car, all right!”

Just then, the light changes, so the guy decides to show the old man what his car can do. He floors it, and within 30 seconds the speedometer reads 320 MPH.

Suddenly, he notices a dot in his rear view mirror.  It seems to be getting closer! He slows down to see what it could be and suddenly, whhhoossh! Something whips by him, going much faster!

“What on earth could be going faster than my 16.4?” the young man asks himself.

Then, ahead of him, he sees a dot coming toward him. Whoooooosh! It goes by again, heading the opposite direction! And, it almost looked like the old man on the moped! “Couldn’t be,” thinks the guy. “How could a moped outrun a Bugatti?”

Again, he sees a dot in his rear view mirror!  Whooooosh Ka-BbblaMMM! It plows into the back of his car, demolishing the rear end. The young man jumps out, and good grief, it is the old man!!!  Of course the moped and the old man are hurting for certain. He runs up to the dying old man and says, “You’re hurt bad! Is there anything I can do for you?”

The old man groans and replies “Yes. Unhook my suspenders from your side-view mirror!”

BACK to our patent writing:

It was only after the patent was in its first draft that the client suddenly found an article about a “new” fetal ultrasound probe, perhaps without specific information on how it works. And since the patent for the fetal probe was unpublished, you couldn’t get any information on how the fetal probe works.


Just in case the fetal probe uses an array of transducers that produces and interprets beams having a short reflection, you decided to add claims about detecting hard objects AND, equally important, to add description about how your foreign body ultrasound probe makes this distinction.

It just so happens that your ultrasound probe includes a device that works similar to a durometer which is defined as “an instrument for measuring the degree of hardness; especially, an instrument for testing the relative hardness of steel rails and the like.”

We made sure that the description includes a definition of a durometer and a description of your durometer works in conjunction with out ultrasound probe. You also included figures that show how your ultrasound beams focus can be focused to cross at very close range or a farther range. This provides us with two backup positions by which to protect your invention. Of course the fetal ultrasound probe does not include a durometer. Additionally you suspect that the beams associated with the fetal ultrasound probe either cannot be focused.

February 3, 2009 at 12:24 am Leave a comment

Drafting Claims of Various Scopes – A Good Strategy!

Greetings inventors, investors, patent drafters and anyone interested in patents! This is Rabbi, Dr. Yosef Freedland, surgeon, and patent attorney; leader of the medical device team Appelfeld Zer Fisher writing to you from the beautiful border of Ramat Gan, along the border of the holy city of Bene Brak; so named because of the many pot holes in the streets. LOL

Before getting into snails, I would like to relate a story about an investor:

Sitting next to each other on a long flight are a young investment banker and an elderly investor, who made money long ago on investments and retired. The young investment banker is thinking that the elderly investor isn’t all that smart and she could easily pull one over on him, possibly as an introduction to derivative mortgage investments that were very popular some time ago when the story took place.

So the young investment banker asks if the elderly investor would like to play a fun game.

The elderly investor is tired and just wants to take a nap, so he politely declines and tries to catch a few winks.

The young investment banker persists, and says, “The game is a lot of fun. I ask you a question, and if you don’t know the answer, you pay me only $5; you ask me one, and if I don’t know the answer, I will pay you $500.”

This catches the elderly investor’s attention and to keep the young investment banker quiet, he agrees to play the game.

The young investment banker asks the first question. ‘What’s the distance from The Earth to the Moon?’ The elderly investor doesn’t say a word, reaches in his pocket pulls out a five-dollar bill, and hands it to the young investment banker.

Now, it’s the elderly investor’s turn.

He asks the young investment banker, “What goes up a hill with three legs, and comes down with four?”

The young investment banker uses her laptop and searches all references she could find on the Net. She sends e-mails to all the smart friends she knows, all to no avail. After one hour of searching she finally gives up. She wakes up the elderly investor and hands him $500.

The elderly investor pockets the $500 and goes right back to sleep.

The young investment banker is going nuts not knowing the answer. She wakes the elderly investor up and asks, ‘Well, so what goes up a hill with three legs and comes down with four?’

The elderly investor shrugs, reaches in his pocket, hands the young investment banker $5 and goes back to sleep.

OK, so much for investment bankers.

So what you’ve been doing is to provide backup positions that allow you to patent your invention. Initially you write broad claims and then you add on claims that provide more and more limitations. In this manner if there are inventions out there that you don’t know about and they are used to challenge your ultrasound probe for finding foreign bodies in a human being, you can combine claims to create a shell that protects your invention.

The reason I use the example of the snail is because the snail carries around its shell and the shell is part of the snail. Similarly a claim set first defines the slug and includes extra claims that can be used to define a protective shell that is part and parcel of our slug, i.e., your broadest claim.

Problem: it turns out that the fish probe actually reflects ultrasound off bones inside the fish, rather than off the fish scales. So in actuality the ultrasound passes through a living body and is reflected from a hard object inside a living body. So in addition to citing the fish probe the examiner disqualifies use of your invention to locate objects in a body.

Solution: you add dependent claims that can be used to distinguish your invention from a fish probe used in lakes. One way to do this may be to describe how your probe includes an array of transducers that are arranged in a way that causes resulting beams that cross. In distinct contrast to fisherman probe uses an array of transducers that produce beams that spread out through the lake.

Another way to go is to include claims that define the invention as having transducers that register the reflected beams following a short period of time. In distinct contrast to fisherman’s probe, it has transducers that register beams following a long period of time.

February 2, 2009 at 12:19 am Leave a comment

Using Dependant Claims to Overcome Relevant Art

Greetings inventors, investors, patent drafters and anyone interested in patents! This is Rabbi, Dr. Yosef Freedland, surgeon, and patent attorney; leader of the medical device team Appelfeld Zer Fisher writing to you from the beautiful border of Ramat Gan, at the border of Bene Brak.

Everything looks dandy here from the 16th floor of the BSR building.

We are still into snails that are being compared to an ultrasound probe that locates foreign bodies in a three-dimensional matrix.

At our last exciting blog installment, you were forced to limit your three-dimensional matrix that could be used anywhere, or on anything; to a living body, and wherein the probe includes transducers for registering reflected beams at short range.

More Problems: you didn’t know about it when you wrote the patent, but there happened to be a three-dimensional fetal ultrasound for use on pregnant women. Unfortunately this fetal ultrasound includes reflected short range beams and is used on a living body. Oy vey!

The examiner just happens to find this fetal probe patent and you get a response from the examiner that not only includes the diamond probe, the fishermen probe, but also the fetal probe. How didn’t you know about this patent to a fetal probe, when even a non-professional search should turn up anything related to probes used on living people? Maybe it wasn’t published before you filed your patent and so you did know about it.

Solution: Fortunately you anticipated that there might be some patent out there where ultrasound is used for imaging a living tissue of a fetus. So what you did when you wrote the patent is you included claims that limit your ultrasound probe to finding inanimate objects in a living tissue. For example, your array of transducers produce beams in a sequence or configuration that reflects only upon reaching a substance with greater hardness than the tissue of a fetus. So if it turns out that the examiner found existing art that invalidates your above noted independent claim, you had in a limitation available to combine into the independent claim. For example, you wrote a dependent claim to a probe that includes a durometer that is configured to distinguish between hard and soft objects.

January 31, 2009 at 11:20 pm Leave a comment

Limiting The Scope of Claims to Avoid Irrelevant Art

Greetings inventors, investors, patent drafters and anyone interested in patents! This is Rabbi, Dr. Yosef Freedland, surgeon, and patent attorney; leader of the Medical Device Team at Appelfeld Zer Fisher — writing to you from the beautiful border of Ramat Gan, at the border of Bene Brak.

We are still into snails, but first a word from our creator.

Adam was wandering around the Garden of Eden feeling very lonely, when he heard a loud voice ask him, “What is wrong with you?” Adam said he didn’t have anyone to talk to, and he was feeling very lonely.

Then the loud voice said he was going to give him a companion and it would be a woman. The voice continued, saying; “this person will cook for you and wash your clothes, she will always agree with every decision you make. She will bear your children and never ask you to get up in the middle of the night to take care of them. She will not nag you, and will always be the first to admit she was wrong when you’ve had a disagreement. She will never have a headache, and will freely give you love and compassion whenever needed.”

Adam thought that sounded great, so he asked “What would a woman like this cost me??”

The voice answered, “an arm and a leg.”

Adam thought about that for a moment. He thought that would be a pretty high price to pay, so he then asked, “What can I get for just a rib???”

The rest is history . . .

Now you still have a problem. It just so happens that fishermen lower and ultrasound probe into a lake and locate fish. When you write the patent you don’t know about this fishing probe possibly because the client was using his last penny to write a good patent and didn’t search the patent database to the full extent.  

Problem: Fish-locating ultrasound probes travel through a matrix including a liquid which is the lake water and reflect off fish. Let’s even assume that the fisherman is provided with a display that shows three-dimensionally where the fish are located. This makes your ultrasound probe invention invalid because your claims could be used to describe the fisherman fish probe.

Solution: you had more claims that depend on the first claim and limit your three-dimensional matrix to living tissue. In this way if the examiner cites a patent to a fisherman fish probe you could combine one or more of these dependent claims into your first claim. In this way, these claims will serve as our snail shell that protects the slug inside.

January 30, 2009 at 10:13 am Leave a comment

Independent Claims and Dependent Claims

Greetings inventors, investors, patent drafters and anyone interested in patents! This is Rabbi, Dr. Yosef Freedland, surgeon, and patent attorney; leader of the Medical Device Team at Appelfeld Zer Fisher — writing to you from the beautiful border of Ramat Gan, at the border of Bene Brak.
Everything looks dandy here from the 16th floor of one of the BSR buildings (there are two BSR buildings. The first is called BSR 1 and the second is called BSR 2 – pretty catchy, huh?).
Before getting back to snails, snail slugs and snail shells, we will pause for a brief news item:


Young Chuck moved to Texas and bought a donkey from a farmer for $100.00.
The farmer agreed to deliver the donkey the next day.
The next day he drove up and said, ‘Sorry son, but I have some bad news, the donkey died.’
Chuck replied, ‘Well, then just give me my money back.’
The farmer said, ‘Can’t do that. I went and spent it already.’
Chuck said, ‘OK, then, just bring me the dead donkey.’
The farmer asked, ‘What ya gonna do with him?
Chuck said, ‘I’m going to raffle him off.’
The farmer said ‘You can’t raffle off a dead donkey!’
Chuck said, ‘Sure I can Watch me. I just won’t tell anybody he’s dead.’
A month later, the farmer met up with Chuck and asked, ‘What happened with that dead donkey?’
Chuck said, ‘I raffled him off. I sold 500 tickets at two dollars apiece and made a profit of $898.00.’
The farmer said, ‘Didn’t anyone complain?’
Chuck said, ‘Just the guy who won. So I gave him his two dollars back.’
Chuck now works for Goldman Sachs.

Anyway, back to snails:

In a patent claim set, there is an independent claim and many dependent claims.

The independent claim describes the invention in the broadest possible fashion and the subsequent claims that depend on the independent claim create more and more limitations so that if you have to you can protect your invention you can limit the invention to the boundaries of the snail shell. But only if absolutely necessary.

Our independent claim might be directed to an ultrasound probe configured with a specific array of beams that can be interpreted by a controller to provide a display (or read-out) of objects in a three-dimensional matrix.

Problem: your independent claim covers the above noted diamond locator.  But it just so happens that there is a patent or an article that you don’t know about. And guess what this patent or article describes an invention that uses ultrasound to locate diamonds in dry dirt.

: your next claim that depends on your independent claim might be to limit your ultrasound probe to find objects in a matrix of including fluids.

Now you want to make the ultrasound beam have some structure that allows it to function in conjunction with a three-dimensional matrix including fluids. So this claim might read that your invention is the same invention in your independent claim, but includes at least one ultrasound transducer that provides ultrasound at a wavelength that passes through a matrix including fluid.
Another dependent claim might be added to state that the ultrasound wave length is additionally configured to reflect off harder objects within the three-dimensional “softer” matrix which includes fluid.
By writing claims that are more limited (and backing them up with a full description) you have a “shell” to protect your basic invention of an ultrasound probe for use in a clinical setting.

January 29, 2009 at 10:49 pm 1 comment

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