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  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">JPSIM</journal-id>
      <journal-title-group>
        <journal-title>Journal of Pakistan Society of Internal Medicine</journal-title>
        <abbrev-title>J Pak Soc Intern Med</abbrev-title>
      </journal-title-group>
      <issn publication-format="print">2709-8729</issn>
      <issn publication-format="electronic">2710-0804</issn>
      <publisher>
        <publisher-name>Pakistan Society of Internal Medicine</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.70302/jpsim.v4i4.2366</article-id>
      <article-id pub-id-type="publisher-id">jpsim.v4i4.2366</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Case Report</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>The 'Ear of Lynx Sign': A Radiodiagnostic Clue in Complicated Hereditary Spastic Paraplegia</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Bano</surname>
            <given-names>Safia</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author" corresp="yes">
          <name>
            <surname>Nawaz</surname>
            <given-names>Ahmad</given-names>
          </name>
          <email>ahmad_nawaz3534@yahoo.com</email>
          <xref ref-type="aff" rid="aff1"/>
          <xref ref-type="corresp" rid="cor1">*</xref>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Iqbal</surname>
            <given-names>Haris</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Numan</surname>
            <given-names>Ahsan</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Iftikhar</surname>
            <given-names>Sadaf</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Khawaja</surname>
            <given-names>M. Abdul Ahad</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Aslam</surname>
            <given-names>Allina</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Suhail</surname>
            <given-names>Laiba</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Umar</surname>
            <given-names>Aqsa</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
      </contrib-group>
      <aff id="aff1">
        <institution>Department of Neurology, King Edward Medical University/ Mayo Hospital Lahore</institution>
      </aff>
      <author-notes>
        <corresp id="cor1">*Correspondence: Ahmad Nawaz (ahmad_nawaz3534@yahoo.com)</corresp>
      </author-notes>
      <pub-date date-type="pub" publication-format="electronic" iso-8601-date="2023-11-29">
        <day>29</day>
        <month>11</month>
        <year>2023</year>
      </pub-date>
      <pub-date date-type="collection" publication-format="electronic">
        <year>2023</year>
      </pub-date>
      <volume>4</volume>
      <issue>4</issue>
      <fpage>324</fpage>
      <lpage>329</lpage>
      <history>
        <date date-type="received" iso-8601-date="2023-07-23">
          <day>23</day>
          <month>07</month>
          <year>2023</year>
        </date>
        <date date-type="accepted" iso-8601-date="2023-09-08">
          <day>08</day>
          <month>09</month>
          <year>2023</year>
        </date>
      </history>
      <permissions>
        <copyright-statement>Copyright © 2023 The Author(s)</copyright-statement>
        <copyright-year>2023</copyright-year>
        <copyright-holder>The Author(s)</copyright-holder>
        <ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/>
        <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
          <ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by/4.0/</ali:license_ref>
          <license-p>This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.</license-p>
        </license>
      </permissions>
      <self-uri xlink:href="https://psimj.com/article/jpsim.v4i4.2366" content-type="text/html"/>
      <self-uri xlink:href="https://psimj.com/article/jpsim.v4i4.2366.pdf" content-type="application/pdf"/>
      <abstract>
        <p>: Hereditary spastic paraplegia, also known as Strumpell-Lorrain disease, encompasses a group of hereditary neurological disorders characterized by progressive spasticity and lower limb weakness due to corticospinal tract degeneration. This condition can manifest clinically as a pure form with pyramidal signs or a complicated form exhibiting a spectrum of additional neurological and non-neurological manifestations. In this report, we present a compelling familial case of three male siblings, product of first-degree consanguinity, presented with complicated hereditary spastic paraplegia. The radiological evaluation of the case revealed noteworthy findings, including a thinning of the corpus callosum and an abnormal T2/FLAIR cone-shaped hyperintensity at the tip of the frontal horn of the lateral ventricles, resembling the tufts of hair crowning the ears of a lynx, termed the "ear of lynx sign." This unique radiological sign, combined with a thin corpus callosum, is commonly observed in genetic subtypes associated with mutations of the SPG11 and SPG15 genes. Considering the limited access and high cost of genetic studies in our region, the recognition and clinical importance of the 'Ear of Lynx Sign' take on utmost significance. This distinctive radiological clue plays a crucial role in early identification of genetic forms of hereditary spastic paraplegia, leading to better disease management, progression control, and overall enhancement of patients' clinical outcomes and quality of life. Our study underscores the significance of such radiodiagnostic signs, particularlyin areas withrestricted availabilityofgenetictesting,emphasizing theirprofoundimpacton patientcareandprognosis.</p>
      </abstract>
      <kwd-group xml:lang="en" kwd-group-type="author-keywords">
        <title>Keywords</title>
        <kwd>Hereditary spastic paraplegia</kwd>
        <kwd>'Ear of Lynx Sign'</kwd>
        <kwd>Radiodiagnostic clue</kwd>
        <kwd>Spastic paraplegin gene 11</kwd>
        <kwd>Spastic paraplegin gene 15</kwd>
      </kwd-group>
    </article-meta>
  </front>
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  <back>
    <ref-list>
      <title>References</title>
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  </back>
</article>
