United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                     ___________

                                   Nos. 96-3247/3312
                                    ___________

Leonard Penney; Helen Penney,              *
                                           *
       Appellants/Cross-Appellees,         *
                                           *   Appeals from the United States District
       v.                                  *   Court for the District of South Dakota.
                                           *
Praxair, Inc.,                             *
                                           *
       Appellee/Cross-Appellant.           *

                                      ___________

                                  Submitted: March 14, 1997
                                      Filed: June 19, 1997
                                    ___________

Before WOLLMAN and BEAM, Circuit Judges, and REASONER,1 District Judge.
                          ___________

BEAM, Circuit Judge.

      Leonard and Helen Penney appeal the district court's2 denial of their motion for
a new trial and the exclusion of certain medical evidence in this personal injury action.




       1
        The Honorable Stephen M. Reasoner, Chief Judge, United States District Court
for the Eastern District of Arkansas, sitting by designation.
       2
      The Honorable John B. Jones, United States District Judge for the District of
South Dakota.
Praxair cross-appeals the district court's denial of judgment as a matter of law as to
future medical expenses. We affirm.

I. BACKGROUND

       This is a diversity action seeking damages for a rear-end collision which
occurred in Iowa. Leonard Penney was sleeping in the front passenger seat of a car
that was hit by a loaded tanker truck owned by Praxair. Because the accident occurred
in a construction zone with reduced speeds, the truck was traveling at only five to ten
miles per hour when the collision occurred. Upon impact, Leonard's head jerked
backward and then snapped forward, resulting in a whiplash effect. Leonard claims
that he suffers headaches, a sore neck, ringing in his ears, dizziness, vertigo, and other
assorted problems as a result of this accident. Leonard was sixty-two years old at the
time of the accident.

       Leonard saw several physicians for relief of his ailments. After both an MRI and
a CT scan detected no brain injury,3 Leonard was referred to Dr. Wu, the Director of
the Brain Imaging Center at the University of California, Irvine. Dr. Wu performed a
Positron Emission Tomography (PET) scan of Leonard's brain. A PET scan measures
glucose intake in the different sections of the brain; i.e., it measures brain function.
Hose v. Chicago Northwestern Transp. Co., 

, 973 (8th Cir. 1995). A
person's PET scan is then compared with PET scans from a control group to detect
abnormalities in the brain. The control group in Leonard's case consisted of thirty-one
persons, with ages ranging from eighteen to seventy. Dr. Wu testified, in a video
deposition, that the results of Leonard's PET scan showed brain abnormalities which



      3
       According to the plaintiffs' submissions, closed head injuries are subtle tears in
the brain tissue. Because the MRI and CT scans measure structural, not functional
changes in the brain, closed head injuries are oftentimes not visible on those tests.

                                           -2-
were consistent with a traumatic brain injury. Plaintiffs intended to use this testimony
to prove the existence of a closed head injury.

       Praxair filed a motion in limine to exclude the PET scan evidence. It argued that
it was not reliable enough to withstand analysis under the Supreme Court's decision in
Daubert v. Merrell Dow Pharm., Inc., 

, 597 (1993) and that the evidence
would not be helpful to the jury. The district court excluded the PET scan results,
reasoning that the evidence would not be helpful to the jury in deciding the issues
when compared with the likelihood that the jury would misapply the evidence.

        The action was tried and the jury found for the plaintiffs. Although it awarded
$14,602 for past medical expenses and $20,000 for future medical expenses, the jury
awarded no damages for loss of function or for pain and suffering. The Penneys moved
for a new trial, claiming such a verdict was facially inconsistent and invalid as a matter
of law. The district court denied the motion. On appeal, the Penneys challenge the
district court's denial of their motion for a new trial and its exclusion of the PET scan
evidence. Praxair cross-appeals, arguing there is no evidence to support the award of
future medical damages.

II. DISCUSSION

      A. New Trial

      The Penneys argue that a new trial on damages is necessary to cure the facially
inconsistent verdict handed down by the jury. We review the district court's denial of
a new trial for an abuse of discretion. Morrison v. Mahaska Bottling Co., 

,
845 (8th Cir. 1994). Applying that standard, we find no error.




                                           -3-
       Under Iowa law,4 whether a particular award of damages is adequate turns on
the facts of each case. Matthess v. State Farm Mut. Auto. Ins. Co., 

,
702 (Iowa 1994). The test is whether the verdict "fairly and reasonably compensates"
a person for the injury sustained. 

fact that the evidence presented at trial
could have supported a higher damages award does not control the decision to grant
a new trial. Foggia v. Des Moines Bowl-O-Mat, Inc., 

, 891 (Iowa
1996). Instead, the court must determine whether, allowing the jury "its right to accept
or reject whatever portions of the conflicting evidence it chose, the verdict effects
substantial justice between the parties." 

case, Praxair disputed both the extent of Leonard's injuries and whether
the collision proximately caused any pain and suffering. Before the accident, Leonard
experienced neck and back problems. Between the time of the accident and trial, he
had a heart attack and two angioplasty surgeries. These pre- and post-accident health
problems are properly for the jury's consideration. McDonnell v. Chally, 

, 615 (Iowa Ct. App. 1994). The jury had a difficult decision to make considering
the evidence offered to discount Leonard's pain and suffering and to show alternative
causes for his injuries. Given the conflicting evidence in this case, we find the damages
award fairly and reasonably compensated Leonard for his injury. Consequently, we
find no abuse of discretion by the district court in denying the plaintiffs' motion for a
new trial on these grounds.


      4
        Sitting in diversity, a district court is bound to apply the choice of law rules of
the state in which it sits, here, South Dakota. Simpson v. Liberty Mut. Ins. Co., 

, 764 (8th Cir. 1994). South Dakota has adopted the most significant
relationship test as its choice of law rule in tort cases. Chambers v. Dakotah Charter,
Inc., 

, 67 (S.D. 1992). The district court determined that Iowa had the
most significant relationship to this accident and, consequently, applied Iowa law. On
appeal, the defendants challenge the application of Iowa law as to the damages issue
only. We find no merit in this argument and apply Iowa law to this case, as did the
district court.

                                           -4-
      B. PET Scan

       The plaintiffs next contend that the district court erred in excluding the evidence
of Leonard's PET scan. Questions regarding the admission of expert evidence are
committed to the sound discretion of the district court and will only be reversed upon
a finding of an abuse of that discretion. Westcott v. Crinklaw, 

, 1075 (8th
Cir. 1995). Applying that standard, we find no abuse of discretion in the district court's
decision to exclude the PET scan evidence in this case.

       General acceptance in the scientific community is no longer a precondition to the
admission of scientific evidence. 

. However, a trial judge
must still ensure that "an expert's testimony both rests on a reliable foundation and is
relevant to the task at hand." 

a preliminary assessment of whether the
reasoning or methodology underlying the testimony is scientifically valid and of
whether that reasoning or methodology properly can be applied to the facts in issue."

In this case, plaintiffs failed to establish a sufficient foundation to
support the admission of the PET scan evidence.

       According to the parties' submissions, PET scan results can be affected by a
person's age, medical history and medications. Because Leonard was sixty-six years
old at the time of the scan, it is not clear from the record exactly how accurate a
comparison this control group could provide. Furthermore, although persons are
normally instructed to remain off medication for seven days prior to the administering
of a PET scan, Leonard submitted to the test while still taking his regular medications
for his heart condition and other maladies. None of the other control-group subjects
was on medication at the time of their PET scans. It is not clear whether these factors
had any effect on the test results. However, it was plaintiffs' burden to establish a
reliable foundation for the PET scan readings. On these facts, plaintiffs did not make




                                           -5-
such a demonstration and it was within the district court's discretion to exclude the
evidence.5

      C. Future Medical Expenses

       Praxair cross-appeals the district court's denial of its motion for judgment as a
matter of law on the award of future medical expenses. Praxair claims there is
insufficient evidence in the record to support such an award. We review the denial of
a motion for judgment as a matter of law de novo, Kaplon v. Howmedica, Inc., 

, 266 (8th Cir. 1996), viewing the evidence in the light most favorable to the jury
verdict. Smith v. World Ins. Co., 

, 1460 (8th Cir. 1994). We do not
reweigh the evidence or consider the credibility of the witnesses. 

awards may not be speculative or conjectural, but must be proven to a reasonable
certainty, Marquardt v. Starcraft Marine, 

, 63 (8th Cir. 1989), judgment as
a matter of law is only appropriate where the evidence is "'susceptible of no reasonable
inference sustaining the position of the nonmoving party.'" 

(quoting White v. Pence, 

, 779 (8th Cir. 1992)). Applying those
standards, we find that there is sufficient evidence in the record to support the jury's
award of future medical expenses.

       The jury was presented with evidence of Leonard's need for additional medical
attention. Both of the Penneys testified that Leonard continued to suffer symptoms
from the accident and that they intended to continue seeking treatment for Leonard's
pain, in spite of their previous lack of success. In addition, several of Leonard's doctors



      5
         As the plaintiffs point out, we have previously upheld the admission of PET
scan evidence. See, e.g., 

. However, because the admission of
scientific evidence in one case does not automatically render that evidence admissible
in another case, we assume that Hose did not present the same evidentiary problems
as does this case.

                                           -6-
testified that Leonard will require medication and treatment in the future. In
determining the amount of future damages, the jury was presented with itemized bills
of past medical expenses and instructed to consider the reasonably necessary medical
expenses to be incurred in the future. From this evidence, the jury could reasonably
estimate the cost of future medical expenses. See, e.g., Baumler v. Hemesath, 

, 654 (Iowa 1995). This record contains sufficient evidence to sustain the
jury's award of future medical expenses.

III. CONCLUSION

      The judgment of the district court is affirmed.

      A true copy.

            ATTEST:

                     CLERK, U.S. COURT OF APPEALS, EIGHTH CIRCUIT.




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