                           UNPUBLISHED

UNITED STATES COURT OF APPEALS
                 FOR THE FOURTH CIRCUIT


MARY J. THOMAS,                          
                  Plaintiff-Appellant,
                  v.                               No. 01-1544
COMMISSIONER OF SOCIAL SECURITY,
               Defendant-Appellee.
                                         
            Appeal from the United States District Court
      for the Western District of North Carolina, at Charlotte.
              Graham C. Mullen, Chief District Judge.
                          (CA-00-104-3)

                       Argued: November 1, 2001

                       Decided: December 17, 2001

      Before WILKINSON, Chief Judge, and WILKINS and
                   KING, Circuit Judges.



Vacated and remanded by unpublished per curiam opinion.


                              COUNSEL

ARGUED: Jeffrey Lynn Bishop, Charlotte, North Carolina, for
Appellant. James Michael Sullivan, Assistant United States Attorney,
Charlotte, North Carolina, for Appellee. ON BRIEF: Robert J. Con-
rad, Jr., United States Attorney, Charlotte, North Carolina, for Appel-
lee.
2            THOMAS v. COMMISSIONER OF SOCIAL SECURITY
Unpublished opinions are not binding precedent in this circuit. See
Local Rule 36(c).


                              OPINION

PER CURIAM:

   Mary J. Thomas appeals the judgment of the district court affirm-
ing the denial of her claims for disability insurance benefits and sup-
plemental security income benefits. After the Administrative Law
Judge ("ALJ") denied her claims, Thomas requested review by the
Appeals Council of the Social Security Administration ("Appeals
Council"). Although she provided the Appeals Council with addi-
tional medical evidence from her treating physician, it denied review.
Because the record is unclear on whether the Appeals Council recog-
nized the additional evidence to be from Thomas’s treating physician,
we vacate and remand.

                                   I.

   On January 30, 1997, Thomas filed applications for disability
insurance benefits and supplemental security income benefits, alleg-
ing that she had been disabled since January 9, 1997.1 Specifically,
Thomas claimed on her Disability Report of January 30, 1997, that
her disabling illnesses were "diabetes, swelling arthritis, high blood
pressure, [and] high cholesterol." Tr. 72. Thomas asserted that her ill-
nesses prevented her from working because they caused finger swells,
blurry vision, headaches, vomiting, and gout. Prior to being laid off
in January 1997, Thomas had worked for approximately ten years as
a hooker in a textile mill, a job classified by the Dictionary of Occu-
pational Titles as "medium work."2 Previously, she had been
    1
     Almost ten years earlier, on November 24, 1987, Thomas filed an
application for supplemental security income benefits. That claim was
denied initially, and she did not pursue an appeal.
   2
     "Medium work" is defined in the Social Security Regulations ("the
Regulations") to include "lifting no more than 50 pounds at a time with
frequent lifting or carrying of objects weighing up to 25 pounds." 20
C.F.R. § 404.1567(c) (2001).
                THOMAS v. COMMISSIONER OF SOCIAL SECURITY                    3
employed as a tagger in a textile mill, a job classified as "light work."3

   At Thomas’s request, the ALJ, in May 1998, conducted a hearing
on her applications for benefits. He heard testimony from Thomas and
considered "the conclusions and treatment notes of the claimant’s
treating and examining physicians, as well as the opinions of the State
Agency Medical Consultants." Tr. 16. On June 22, 1998, the ALJ
issued his detailed Notice of Decision denying Thomas’s applications
for benefits. Although he agreed that the medical evidence established
that Thomas suffered from "severe" impairments, including diabetes
mellitus, hypertension, gout, a heel spur, and osteoarthritis, the ALJ
found that Thomas did not meet or equal the criteria of any impair-
ment listed in 20 C.F.R. § 404, Subpart P, Appendix 1 (2001), and he
also found that she retained the functional capacity to perform light
work. Tr. 18-19. As such, the ALJ determined that Thomas was not
under a disability as defined by the Social Security Act ("the Act").4

   On July 7, 1998, Thomas filed with the Appeals Council a "Re-
quest for Review of Hearing Decision/Order." On December 21,
1998, while her request for review was pending, an additional physi-
cian, Dr. Josephine Lake, examined Thomas. Dr. Lake diagnosed
  3
   The Regulations define "light work" as:
      lifting no more than 20 pounds at a time with frequent lifting or
      carrying of objects weighing up to 10 pounds. Even though the
      weight lifted may be very little, a job is in this category when it
      requires a good deal of walking or standing, or when it involves
      sitting most of the time with some pushing and pulling of arm
      or leg controls. To be considered capable of performing a full or
      wide range of light work, you must have the ability to do sub-
      stantially all of these activities.
20 C.F.R. § 404.1567(b) (2001).
  4
    Under the Act, the term "disability" is defined as:
      [an] inability to engage in any substantial gainful activity by rea-
      son of any medically determinable physical or mental impair-
      ment which can be expected to result in death or which has
      lasted or can be expected to last for a continuous period of not
      less than 12 months.
42 U.S.C. § 423(d)(1)(A).
4                THOMAS v. COMMISSIONER OF SOCIAL SECURITY
Thomas as suffering from (1) gout with chronic pain of the left knee;
(2) poorly-controlled diabetes; and (3) migraine headaches that
occurred weekly, lasted hours, and were associated with vomiting. Dr.
Lake then completed two reports, a "Sedentary Work Disability State-
ment" and a "Light Work Disability Statement" (collectively "Dr.
Lake’s Disability Reports"), concluding in the former that Thomas
was unable to perform "sedentary work,"5 and in the latter that she
was unable to perform light work. Tr. 224-25. On December 30,
1998, Thomas provided the Appeals Council with both of Dr. Lake’s
Disability Reports. By letter dated January 7, 1999, Thomas’s lawyer
provided the Appeals Council with five additional pages of medical
records on Thomas, described as "[m]edical reports and lab work
from Anson Regional Medical Services" ("Anson Medical Records").6
These records reflect medical examinations and related information
concerning Thomas, conducted at Anson Regional Medical Services
in Wadesboro, North Carolina, on December 3, 4, 9, and 23, 1998.

   Over a year later, on February 25, 2000, the Appeals Council
denied Thomas’s request for review. As a result, the ALJ’s Notice of
Decision of June 22, 1998, constitutes the final decision of the Com-
missioner of Social Security (the "Commissioner") on Thomas’s
applications for disability insurance benefits and supplemental secur-
ity income benefits. See 20 C.F.R. § 404.981 (2001) (explaining that
denial of request for review by Appeals Council renders ALJ’s deci-
    5
     "Sedentary work" is defined by the Regulations as involving:
        lifting no more than 10 pounds at a time and occasionally lifting
        or carrying articles like docket files, ledgers, and small tools.
        Although a sedentary job is defined as one which involves sit-
        ting, a certain amount of walking and standing is often necessary
        in carrying out job duties. Jobs are sedentary if walking and
        standing are required occasionally and other sedentary criteria
        are met.
20 C.F.R. § 404.1567 (2001).
  6
    The January 7, 1999, letter from Thomas’s lawyer to the Appeals
Council does not identify the physician from whom the medical reports
and lab work originated. On inspection, however, the signature or initials
of Dr. Lake appear on four of the five pages of the records accompanying
the letter. As such, it appears that the Anson Medical Records relate to
Dr. Lake’s treatment of Thomas.
             THOMAS v. COMMISSIONER OF SOCIAL SECURITY                 5
sion binding). Although the Appeals Council denied Thomas’s
request for review, it received and filed the new evidence, i.e., Dr.
Lake’s Disability Reports and the Anson Medical Records, into
Thomas’s administrative record. The Appeals Council explained,
however, that it had "considered the contentions raised in your repre-
sentative’s [appeal] letter dated August 5, 1998, as well as the addi-
tional evidence also identified on the attached Order of the Appeals
Council, but concluded that neither the contentions nor the additional
evidence provide[d] a basis for changing the Administrative Law
Judge’s decision." Tr. 5.

   Pursuant to the provisions of 42 U.S.C. § 405(g), Thomas then ini-
tiated this civil action in the Western District of North Carolina, seek-
ing review of the Commissioner’s denials of her applications for
benefits. Her case was referred to the United States Magistrate Judge
and, on February 16, 2001, he issued a detailed Memorandum and
Recommendation concluding that summary judgment should be
awarded to the Commissioner and that the ALJ’s decision should be
affirmed. Thomas v. Halter, Memorandum and Recommendation, No.
3:00CV104-MU (W.D.N.C. Feb. 16, 2001). After conducting its inde-
pendent review of the record, the district court, on March 16, 2001,
issued its Order accepting the recommendation of the Magistrate
Judge, Thomas v. Halter, Order, 3:00CV104-MU (W.D.N.C.
Mar. 16, 2001), and entered summary judgment for the Commis-
sioner. Thomas v. Commissioner, Judgment in a Civil Case,
3:00cv104MU (W.D.N.C. Mar. 16, 2001).

   Thomas filed her timely notice of appeal on April 6, 2001. In this
appeal, she contends that the Appeals Council erred by failing to give
appropriate weight to Dr. Lake’s Disability Reports and the Anson
Medical Records.7 We possess jurisdiction pursuant to 28 U.S.C.
§ 1291.

  7
   Thomas also maintains on appeal that the ALJ erred in rejecting the
functional capacity assessment of her other treating physician, Dr. Floyd
Deen. Because we remand based on Dr. Lake’s status as a treating physi-
cian, any analysis by this Court of the ALJ’s decision to discount Dr.
Deen’s functional capacity assessment would be premature.
6            THOMAS v. COMMISSIONER OF SOCIAL SECURITY
                                  II.

   As a general proposition, our review of the ALJ’s denial of disabil-
ity insurance benefits and supplemental security income benefits is
limited to determining whether such a decision is supported by sub-
stantial evidence. Craig v. Chater, 76 F.3d 585, 589 (4th Cir. 1996).
Substantial evidence has been described as "such relevant evidence as
a reasonable mind might accept as adequate to support a conclusion."
Richardson v. Perales, 402 U.S. 389, 401 (1971) (internal citations
and quotations omitted); NLRB v. Peninsula Gen. Hosp. Med. Ctr., 36
F.3d 1262, 1269 (4th Cir. 1994) (same). In order for this Court to
determine whether the ALJ’s decision is supported by substantial evi-
dence, we must first assess whether the Commissioner has provided
adequate information to explain its decision. Gordon v. Schweiker,
725 F.2d 231, 235 (4th Cir. 1984) ("We cannot determine if findings
are unsupported by substantial evidence unless the Secretary explic-
itly indicates the weight given to all of the relevant evidence.").

                                 III.

   Thomas maintains on appeal that the Commissioner erred in failing
to adequately consider Dr. Lake’s Disability Reports and the Anson
Medical Records. Because, as we explain below, we are unable to
determine from the record whether the Appeals Council understood
Dr. Lake to be a treating physician, we now remand for further devel-
opment of the record.

   As we have observed, Dr. Lake diagnosed Thomas with gout with
chronic pain of the left knee; poorly-controlled diabetes; and migraine
headaches that occurred weekly, lasted hours, and were associated
with vomiting. Dr. Lake then concluded that Thomas could not per-
form even sedentary work. Because she examined Thomas in Decem-
ber 1998, after the ALJ issued his June 1998 decision, the ALJ was
not afforded an opportunity to consider Dr. Lake’s Disability Reports
and the Anson Medical Records. The Appeals Council, however, con-
sidered both submissions, and it added them to Thomas’s administra-
tive record. Ultimately, however, the Appeals Council offered only
the ambiguous explanation "that neither the contentions nor the addi-
tional evidence provide[d] a basis for changing the Administrative
Law Judge’s decision." Tr. 5.
             THOMAS v. COMMISSIONER OF SOCIAL SECURITY                  7
   It has long been settled that "[r]eviewing courts are restricted to the
administrative record in performing their limited function of deter-
mining whether the Secretary’s decision is supported by substantial
evidence." Wilkins v. Secretary, DDHS, 953 F.2d 93, 96 (4th Cir.
1991) (en banc) (quoting Huckabee v. Richardson, 468 F.2d 1380,
1381 (4th Cir. 1972)). Although the Appeals Council discounted the
"additional evidence," it specifically incorporated Dr. Lake’s Disabil-
ity Reports and the Anson Medical Records into Thomas’s adminis-
trative record. We are obliged to review the record as a whole,
including the evidence added to the administrative record by the
Appeals Council subsequent to the ALJ’s decision, in determining
whether substantial evidence supports the ALJ’s findings. Id.

   The Magistrate Judge discounted Dr. Lake’s Disability Reports, at
least in part, because he understood that "Dr. Lake was not a treating
physician." J.A. 17. Until oral argument of this appeal, the Commis-
sioner likewise represented to this Court that Dr. Lake was not Thom-
as’s treating physician. At argument the Commissioner’s counsel
candidly corrected this error, and he acknowledged to us that Dr.
Lake was a treating physician. From this record, however, we are
unable to discern whether the Appeals Council, like the Magistrate
Judge, failed to correctly understand that Dr. Lake was Thomas’s
treating physician. Indeed, its statement discounting the "additional
evidence" gives no indication whether it understood Dr. Lake to be
a treating physician. As this Court has stated, "[j]udicial review of an
administrative decision is impossible without an adequate explanation
of that decision by the administrator." DeLoatche v. Heckler, 715
F.2d 148, 150 (4th Cir. 1983). See also Riley v. Apfel, 88 F. Supp. 2d
572, 579-80 (W.D. Va. 2000) ("When this court is left in the dark as
to how the Appeals Council treated the new evidence a meaningful
judicial review is impossible.").

   Whether the Appeals Council properly recognized Dr. Lake to be
a treating physician is significant to the Thomas disability determina-
tion primarily because "the treating physician rule generally requires
a court to accord greater weight to the testimony of a treating physi-
cian." Hunter v. Sullivan, 993 F.2d 31, 35 (4th Cir. 1992) (per
curiam); see also Coffman v. Bowen, 829 F.2d 514, 517 (4th Cir.
1987) ("[The treating physician] rule requires that the opinion of a
claimant’s treating physician be given great weight and may be disre-
8            THOMAS v. COMMISSIONER OF SOCIAL SECURITY
garded only if there is persuasive contradictory evidence."); Mitchell
v. Schweiker, 699 F.2d 185, 187 (4th Cir. 1983) (same).

   Because of the ambiguity in the record, and in light of the treating
physician rule, we believe the district court should remand this case
to the Commissioner for further development of the record. The Com-
missioner should then evaluate Dr. Lake’s Disability Reports, as well
as the Anson Medical Records, while giving appropriate consider-
ation to Dr. Lake’s status as a treating physician.

                                  IV.

   Pursuant to the foregoing, we vacate the judgment and remand. The
district court should return this case to the Commissioner for such fur-
ther proceedings as may be appropriate.

                                        VACATED AND REMANDED
