{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T03:57:31Z","timestamp":1792036651929,"version":"4.4.0"},"reference-count":16,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"1","license":[{"start":{"date-parts":[[2018,3,6]],"date-time":"2018-03-06T00:00:00Z","timestamp":1520294400000},"content-version":"vor","delay-in-days":1,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["NEUROSURGERY","NEUROS"],"published-print":{"date-parts":[[2019,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>BACKGROUND<\/jats:title>\n                    <jats:p>The optimal observation interval after the radiosurgical treatment of a sporadic vestibular schwannoma, prior to salvage intervention, is unknown.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>To determine an optimal postradiosurgical treatment interval for differentiating between pseudoprogression and true tumor growth by analyzing serial volumetric data.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>METHODS<\/jats:title>\n                    <jats:p>This single-institution retrospective study included all sporadic vestibular schwannomas treated with Gamma Knife radiosurgery (Eketa AB, Stockholm, Sweden; 12\u201313 Gy) from 2002 to 2014. Volumetric analysis was performed on all available pre- and posttreatment magnetic resonance imaging scans. Tumors were classified as \u201cstable\/decreasing,\u201d \u201ctransient enlargement\u201d, or \u201cpersistent growth\u201d after treatment, based on incrementally increasing follow-up durations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>\n                      A total of 118 patients included in the study had a median treatment tumor volume of 0.74 cm\n                      <jats:sup>3<\/jats:sup>\n                      (interquartile range [IQR] = 0.34\u20131.77 cm\n                      <jats:sup>3<\/jats:sup>\n                      ) and a median follow-up of 4.1 yr (IQR = 2.6\u20136.0 yr). Transient tumor enlargement was observed in 44% of patients, beginning at a median of 1 yr (IQR = 0.6\u20131.4 yr) posttreatment, with 90% reaching peak volume within 3.5 yr, posttreatment. Volumetric enlargement resolved at a median of 2.4 yr (IQR 1.9\u20133.6 yr), with 90% of cases resolved at 6.9 yr. Increasing follow-up revealed that many of the tumors initially enlarging 1 to 3 yr after stereotactic radiosurgery ultimately begin to shrink on longer follow-up (45% by 4 yr, 77% by 6 yr).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSION<\/jats:title>\n                    <jats:p>Tumor enlargement within \u223c3.5 yr of treatment should not be used as a sole criterion for salvage treatment. Patient symptoms and tumor size must be considered, and giving tumors a chance to regress before opting for salvage treatment may be worthwhile.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/neuros\/nyy019","type":"journal-article","created":{"date-parts":[[2018,1,15]],"date-time":"2018-01-15T23:09:52Z","timestamp":1516057792000},"page":"123-131","source":"Crossref","is-referenced-by-count":55,"title":["Temporal Dynamics of Pseudoprogression After Gamma Knife Radiosurgery for Vestibular Schwannomas\u2014A Retrospective Volumetric Study"],"prefix":"10.1227","volume":"84","author":[{"given":"Jonathan D","family":"Breshears","sequence":"first","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joseph","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Head and Neck Surgery, University of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annette M","family":"Molinaro","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, San Francisco, California"},{"name":"Department of Epidemiology and Biostatistics, Uni-versity of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Penny K","family":"Sneed","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, University of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael W","family":"McDermott","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aaron","family":"Tward","sequence":"additional","affiliation":[{"name":"Department of Otolaryngology, Head and Neck Surgery, University of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip V","family":"Theodosopoulos","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of California, San Francisco, San Francisco, California"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2019,1]]},"reference":[{"issue":"8","key":"bib1-20231011","first-page":"1540","article-title":"Serial follow-up MR imaging after gamma knife radiosurgery for vestibular schwannoma","volume":"21","author":"Nakamura","year":"2000","journal-title":"AJNR Am J Neuroradiol"},{"issue":"supp 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