IN RE: Bard Implanted Port Catheter Products Liability Litigation

1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
WO
IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF ARIZONA
IN RE: Bard Implanted Port Catheter
Products Liability Litigation MDL No. 3081
ORDER
K. Andre Mkhoyan, Ph.D.
This multidistrict litigation (“MDL”) involves thousands of personal injury cases
related to implanted port catheters (“IPCs” or “ports”) designed, manufactured, and
marketed by Defendants Becton Dickenson and Company, C. R. Bard, Inc., Bard Access
Systems, Inc., and Bard Peripheral Vascular, Inc. (collectively, “Defendants” or “Bard”).
Plaintiffs have filed a motion to exclude the expert opinions of K. Andre Mkhoyan, Ph.D.
Doc. 5177. The motion is fully briefed and no party requests oral argument. See Docs.
5177, 5754, 6019. The Court will deny the motion.
I. Background.
An IPC is a medical device surgically implanted under the skin to provide repeated
access to a patient’s vascular system without the need for multiple needlesticks into
peripheral veins. IPCs are used to deliver chemotherapy and immunotherapy medication,
intravenous fluids, blood transfusions, and parenteral nutrition. IPCs can remain in place
for weeks, months, or even years until treatment is completed.
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 1 of 9

2
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
IPCs consist of a port and a catheter. The port is a small reservoir disc with a self-
sealing silicone center where a needle can be inserted to deliver medication. The port
typically is implanted beneath the chest skin and below the collarbone. Port bodies vary
in shape and size and are made of plastic, silicone, or titanium. The port is attached to a
catheter, which is a thin flexible tube for delivery of the medication to a vein. The catheter
is tunneled under the skin to an insertion point in a central vein. Catheters vary in width
and are made of silicone or polyurethane. IPCs typically are implanted by an interventional
radiologist or a vascular surgeon. A nurse or other medical professional then accesses the
IPC to inject the medication, which flows from the port to the catheter and into the vein.
This MDL involves multiple versions of Bard IPCs, each of which received
premarket clearance from the Food and Drug Administration (“FDA”). Bard IPCs contain
barium sulfate, a radiopaque substance that can be seen on diagnostic imaging such as
X-ray, CT, and MRI scans. Several Bard IPCs are manufactured using polyoxymethylene
(“POM”), an acetal thermoplastic polymer, in the construction of the port. Many Bard
IPCs have a port with raised palpation bumps on the silicone center, which help identify
these IPCs as power-injectable devices.
Each Plaintiff in this MDL had a Bard IPC implanted in his or her body, and claims
it was defective and caused serious injury. Plaintiffs allege that the barium sulfate in the
IPC degrades the mechanical integrity of the catheter, leading to surface irregularities that
cause catheter fracture, infection, and blood clots. Plaintiffs further allege that Bard’s
manufacturing process for the POM-containing IPCs lacks adequate measures to stabilize
the POM to prevent oxidative degradation, which causes cracks, fissures, and other
physical defects in the polymer and increases the risk of fracture, infection, and thrombosis.
Plaintiffs also allege that the palpation bumps on the power-injectable IPCs cause undue
compression stress on the tissue surrounding the port, leading to ulceration and tissue
necrosis. See Docs. 23, 1889.
Plaintiffs claim that safer alternative designs and manufacturing processes were
available to Bard and that Bard IPCs are more dangerous than other available treatment
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 2 of 9

3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
options. Plaintiffs assert a host of state law claims, including design and manufacturing
defects, failure to warn, breach of warranty, misrepresentation, concealment, and consumer
fraud and unfair trade practices. See Docs. 23, 1889.
Bard disputes Plaintiffs’ allegations and contends its IPCs are safe and effective and
that the medical community is aware of risks associated with IPCs. Bard further contends
that various factors impact the performance and wear of IPCs, including where the catheter
is inserted and how well the device is maintained by medical professionals and the patient.
See Docs. 23, 2023-1.
The parties plan to use various expert witnesses at trial, including materials science
experts. Defendants have identified K. Andre Mkhoyan, Ph.D., as a materials science
expert. Dr. Mkhoyan holds a Ph.D. in Applied Physics and is a professor in the Department
of Chemical Engineering and Materials Science at the University of Minnesota. Doc.
5177-1 at 3. He has conducted research in Electron Microscopy since 1999, including on
SEM analysis, which has resulted in Mkhoyan publishing over 200 peer reviewed papers.
Id. at 3-4. Through his long-standing membership with the Microscopy Society of
America, Mkhoyan has participated in numerous national and international conferences,
including “often participat[ing] in panel discussions for electron microscopy related topics
organized by the National Science Foundation.” Id. at 5. Plaintiffs move to exclude his
opinions under Federal Rule of Evidence 702.
II. Legal Standard.
Rule 702 provides that “[a] witness who is qualified as an expert by knowledge,
skill, experience, training, or education may testify in the form of an opinion” if the
proponent of the expert’s testimony “demonstrates to the court that it is more likely than
not that” (a) “the expert’s scientific, technical, or other specialized knowledge will help the
trier of fact to understand the evidence or to determine a fact in issue,” (b) “the testimony
is based on sufficient facts or data,” (c) “the testimony is the product of reliable principles
and methods,” and (d) “the expert’s opinion reflects a reliable application of the principles
and methods to the facts of the case.” Fed. R. Evid. 702(a)-(d). The proponent of the
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 3 of 9

4
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
expert testimony must show by a preponderance of the evidence that the testimony satisfies
each of these requirements. Fed. R. Evid. 104(a); Fed. R. Evid. 702 advisory committee’s
note to 2023 amendment (“[T]he rule has been amended to clarify and emphasize that
expert testimony may not be admitted unless the proponent demonstrates to the court that
it is more likely than not that the proffered testimony meets the admissibility requirements
set forth in the rule.”); Engilis v. Monsanto Co., 151 F.4th 1040, 1050 (9th Cir. 2025)
(“Consistent with the 2023 amendment, our precedent establishes that Rule 702 requires a
proponent of expert testimony to demonstrate each of the requirements of Rule 702 by a
preponderance of the evidence.”).
The Court acts as a gatekeeper to ensure that expert testimony satisfies Rule 702.
Daubert v. Merrell Dow Pharms., Inc., 509 U.S. 579, 597 (1993). The Court’s task is not
to decide whether the expert is right or wrong, but to ensure the proposed opinions satisfy
Rule 702. Alaska Rent-A-Car, Inc. v. Avis Budget Grp., 738 F.3d 960, 969-70 (9th Cir.
2013); Engilis, 151 F.4th at 1050. If the proponent does not meet its Rule 702 burden, the
expert testimony is not admissible. See Davis v. McKesson Corp., No. CV-18-1157-PHX-
DGC, 2019 WL 3532179, at *3 n.2 (D. Ariz. Aug. 2, 2019) (“[T]he Court may admit expert
opinions only if it can determine, under Rule 104(a), that Plaintiffs have shown each of the
Rule 702 requirements to be satisfied by a preponderance of the evidence.”).
III. Discussion.
Mkhoyan opines there are “methodological and other flaws” in the report of
Plaintiffs’ expert, Dr. El-Ghannam, which “render his opinions wholly unreliable.” Doc.
5177-1 at 5-6. Mkhoyan lists four alleged flaws, one of which is the thickness of the metal
coating applied in Dr. El-Ghannam’s SEM analysis. Id. at 6. Plaintiffs challenge
Mkhoyan’s coating thickness opinions.
A. Challenges under Rule 702(b) and (c).
Plaintiffs argue Mkhoyan’s coating thickness opinions should be excluded under
Rule 702(b) and (c) because they are “based on a single measurement” of the coating’s
thickness taken not from a catheter but from the tape Dr. El-Ghannam used to affix
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 4 of 9

5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
catheters during his SEM analysis. Doc. 5177 at 5-6. They argue Mkhoyan cannot
“extrapolat[e] from a single measurement taken on one adhesive copper tape with different
physical properties than the . . . catheters, and upon which the metal atoms might have
fallen or condensed differently than they did on the catheters.” Id. at 7.
Defendants contend Mkhoyan’s opinions are not solely based on a single
measurement of the coating on the tape, but instead, on “(1) coating thickness
measurements on both tape and catheters; (2) extensive hands-on examination of catheter
samples; (3) visual analysis of Dr. El-Ghannam’s own images; (4) properly controlled
microscopy showing actual catheter characteristics; and (5) application of established
electron microscopy principles.” Doc. 5754 at 6. Defendants do not cite any part of
Mkhoyan’s report, however, to show he measured the coating thickness on catheters as
opposed to tape. They cite figure 13 of his report, which only shows he observed cracking
during Dr. El-Ghannam’s SEM analysis. Mkhoyan confirmed during his deposition that
he did not measure the coating of the catheter in figure 13. Doc. 5754-2 at 5-7.
The Court nonetheless concludes that Mkhoyan’s coating thickness opinions are
supported by sufficient facts and data and a reliable methodology. In his report, Mkhoyan
states that “[s]ince the catheters and the double-sided copper tape on which they are
mounted were coated with a layer of platinum at the same time, the thickness of the coated
platinum layer can be measured from the sample as well as from the tape,” and that “[a]
best practice for measuring the thickness of the coated metal layer is to find a region on the
sample or on the tape that is aligned vertically.” Doc. 5177-1 at 26; see also Doc. 5177-2
at 12-13 (Mkhoyan testifying it is “common practice” to measure the coating on the tape
to avoid “ruining” or “modifying the sample”).
Mkhoyan then explains he took measurements from the tape, which “reveal[ed] a
120-150 nm thick platinum layer,” and his report contains two figures in support. Doc.
5177-1 at 28-29 (figures 10 and 11). He opines this measurement “is more than 10 times
the appropriate level for proper SEM imaging.” Id. at 26; see also Doc. 5177-2 at 35
(Mkhoyan testifying that a “reliable SEM analysis” should apply “no more than a 10,
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 5 of 9

6
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
15[nm]” coating). Mkhoyan’s measurements greatly exceed the 15nm coating Dr. El-
Ghannam claims to have applied in his SEM analysis. Doc. 5202-1 at 8.
When asked whether he measured the coating of a catheter from Dr. El-Ghannam’s
SEM analysis as opposed to the coating of the tape, Mkhoyan testified that figures 22 and
23 of his report contain images of catheters showing “metal flakes” and “a scale bar” that
can be used to estimate the coating thickness. Docs. 5177-1 at 43-44, 5754-2 at 9-11.
Mkhoyan also “review[ed] . . . the images provided in Dr. El-Ghannam’s expert report and
rebuttal report,” as acknowledged by Plaintiffs. Doc. 5177 at 5.
The Court is satisfied Mkhoyan’s testing as discussed above – which provided
measurements of the coating thickness from Dr. El-Ghannam’s SEM analysis – coupled
with his review of Dr. El-Ghannam’s report and rebuttal report, is a sufficient factual basis
for his coating thickness opinions.
Those opinions are also supported by a reliable methodology. Mkhoyan is a
professor in the Department of Chemical Engineering and Materials Science at the
University of Minnesota, where he teaches numerous courses on Electron Microscopy.
Doc. 5177-1 at 3-4. He has conducted research on Electron Microscopy since 1999,
including research on SEM analysis that has focused in part on “methodology
development.” Id. He has published over 200 peer-reviewed papers. Id. His experience
serves as a reliable methodology for his opinions criticizing the methodology of Dr. El-
Ghannam’s SEM analysis. See Geiger v. Creative Impact Inc., No. CV-18-01443-PHX-
JAT, 2020 WL 3268675, at *6 (D. Ariz. June 17, 2020) (“An expert’s opinion can be based
on ‘the application of extensive experience,’ which satisfies Rule 702(c)’s requirement that
an expert opinion be based upon reliable principles and methods.” (quoting Fed R. Evid.
702 notes for the 2000 amendments)).
Plaintiffs argue Mkhoyan admitted “there is no basis in literature or generally
accepted scientific practices allowing materials engineers to determine the thickness” of a
catheter’s coating based on the thickness of the affixed tape’s coating. Doc. 5177 at 11
(citing Doc. 5177-2 at 12-13). Mkhoyan made no such admission. He acknowledged he
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 6 of 9

7
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
cites no source that discusses measuring the coating from tape, but he explained that
measuring the tape’s coating is “common sense” because the thickness “should be the same
as a sample,” and this method prevents “ruining” or “modifying the sample.” Doc. 5177-
2 at 12-13. He testified this method is “common practice” (id. at 13), and explained in his
report it is a “best practice” (Doc. 5177-1 at 26). Mkhoyan’s experience in SEM analysis
(id. at 3-4) supports this opinion. See Elosu v. Middlefork Ranch Inc., 26 F.4th 1017, 1024
(9th Cir. 2022) (“An expert’s specialized knowledge and experience can serve as the
requisite ‘facts or data’ on which they render an opinion.”); Geiger, 2020 WL 3268675, at
*6. The Court cannot conclude his coating thickness opinions are unreliable merely
because he provides measurements from the tape rather than the adjacent catheter.
Plaintiffs argue Mkhoyan “purports to opine on the thickness of the metallic layer
on every single catheter analyzed by Dr. El-Ghannam by extrapolating from a single
measurement” from the tape. Doc. 5177 at 7; see also Doc. 6019 at 5. They cite Ninth
Circuit case law where expert testimony was excluded based on an insufficient sample size.
Doc. 5177 at 10. But Plaintiffs cite nowhere in Mkhoyan’s report where he opines all the
catheters analyzed by Dr. El-Ghannam had an overly thick coating. Instead, he opines the
coating “in some instances approaches and even exceeds an order of magnitude greater
than indicated and needed.” Doc. 5177-1 at 6, 27 (referring to figure 10 of his report to
opine “the platinum films deposited on these catheter samples are inordinately thick”
(emphasis added)). This opinion is supported by Mkhoyan’s testing as discussed above.
Plaintiffs argue that Mkhoyan, to opine that “all of Dr. El-Ghannam’s SEM images
are unreliable because they have too thick of a metal layer,” “needed to assess a large
enough sample size to determine the frequency at which there was too thick of a metal
layer, not just whether any one sample had too much metal.” Doc. 5177 at 11. Their reply
cites Mkhoyan’s deposition testimony where he acknowledges that a greater sample size is
optimal to determine the frequency of a methodological flaw. Docs. 6019 at 7, 5177-2 at
5-6. Plaintiffs are free to cross-examine Mkhoyan about his limited testing, but the Court
will not exclude his opinion on this basis.
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 7 of 9

8
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Plaintiffs argue the tape that Mkhoyan measured has “different physical properties
than the polyurethane or silicone catheters, and upon which the metal atoms might have
fallen or condensed differently than they did on the catheters.” Doc. 5177 at 7; see also
Doc. 6019 at 2. This criticism of Mkhoyan’s testing is also appropriate for cross-
examination, but not to exclude his otherwise supported coating thickness opinions.
Nor is defense expert Dr. Grainger’s opinion that the “sputter coater model used by
Dr. El-Ghannam[] can yield uneven coating thickness” a basis to exclude Mkhoyan’s
opinions. Doc. 5177 at 7-8 (quoting Doc. 5177-5 at 34); see also Doc. 6019 at 4-5. That
Dr. Grainger expects sputter coating to result in uneven coating does not preclude Mkhoyan
from opining on the basis of his expertise and experience that Dr. El-Ghannam’s SEM
analysis resulted in coating thickness that “in some instances” was “greater than indicated
and needed” (Doc. 5177-1 at 6), “more than 10 times the appropriate level for proper SEM
imaging” (id. at 26), and that this methodological flaw combined with others identified by
Mkhoyan renders Dr. El-Ghannam’s SEM analysis unreliable (id. at 5).
Plaintiffs contend Mkhoyan “testified that two images from Figure 22 in his report
allowed him to estimate metal thickness from the catheter sample shown, but this estimate
was not actually presented in his report.” Doc. 5177 at 8; see also Doc. 5177-2 at 18-19.
They further contend Mkhoyan testified that the coating thickness cannot be measured in
many of Dr. El-Ghannam’s SEM images because “the metal layer needs to be from the
side view to have an estimate of thickness.” Doc. 5177-2 at 38. But neither of these
contentions undermine the measurements Mkhoyan did provide through his testing,
presented in figures 10 and 11 of his report.1 See Smilovits v. First Solar, Inc., No. CV12-
00555-PHX-DGC, 2019 WL 6875492, at *5 (D. Ariz. Dec. 17, 2019) (“[U]nless an
expert’s opinion lacks enough accurate factual information to provide a reasonable factual
foundation, criticism of an expert’s decision to base an opinion on some facts but not others
1 Plaintiffs’ related contention – that the SEM images in the appendix of Dr. MacLean’s
report provide no coating thickness measurements and are oriented in a way that they
cannot be reliably measured – is irrelevant because as Plaintiffs acknowledge, Mkhoyan
never claimed to rely on those images. Doc. 5177 at 9.
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 8 of 9

9
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
should be challenged through the traditional means at trial, not through a Daubert motion.”
(citation modified)).
B. Contrary Evidence Challenge.
Plaintiffs argue Mkhoyan acknowledged many of Dr. El-Ghannam’s SEM images
“undermine[] his ‘thick metal’ theory.” Doc. 5177 at 11. They cite numerous SEM images
showing fine surface details of the catheters analyzed by Dr. El-Ghannam. Id. at 12.
Mkhoyan testified surface details would not be visible if the metal coating was too thick,
yet he “offered no comment on these images[.]” Id. (citation omitted). Defendants argue
the fact some surface details are visible “does not disprove excessive coating thickness in
other areas or samples because there is no way to corroborate the metal thickness purely
based on the images,” and where Mkhoyan explained many of the SEM images could not
be analyzed for coating thickness due to the positioning of the catheters. Docs. 5754 at 17,
5177-2 at 37-38. As explained above, Mkhoyan never opines that all catheters of Dr. El-
Ghannam’s SEM analysis contained too thick a coating. He instead opines that Dr. El-
Ghannam “improperly coat[ed the catheters] with a layer of metal that in some instances .
. . exceeds an order of magnitude greater than indicated and needed.” Doc. 5177-1 at 6.
That surface details are visible on some SEM images is not inconsistent with this opinion.
C. Concluding Thought.
As should be apparent from this and other orders dealing with the SEM analyses in
this case, the Court finds both parties’ SEM experts to be well credentialed and highly
experienced, and finds a sufficient basis for their opinions. See Docs. 7432 (Grainger),
10030 (El-Ghannam), 10058 (El-Ghannam case-specific). The Court’s task is not to decide
which expert is right. These experts clear the Rule 702 hurdle, and the jury should hear
from them and weigh their credibility.
IT IS ORDERED that Plaintiffs’ motion to exclude the opinions of K. Andre
Mkhoyan, Ph.D. (Doc. 5177) is denied.
Dated this 17th day of August, 2026.
Case 2:23-md-03081-DGC Document 10112 Filed 08/17/26 Page 9 of 9