title: DBS candidates that fall short on a levodopa challenge test: alternative and important indications.
abstract: BACKGROUND
  Candidacy for deep brain stimulation (DBS) in Parkinson disease (PD) is typically assessed by the preoperative motor response to levodopa along with an interdisciplinary evaluation. However, recent cases treated at our institution have achieved good outcomes with DBS despite a sub-30% improvement in motor scores. The aim of this study was to examine the outcomes of DBS in a subset of patients who failed to reach the 30% motor improvement threshold.
  
  
  METHODS
  A review of all DBS patients treated at the University of Florida Movement Disorders Center between 2002 and 2009 was performed utilizing a DBS database. All patients with sub-30% improvement in Unified Parkinson Disease Rating Scale Part III after dopaminergic medication administration were included.
  
  
  RESULTS
  Nine patients were identified; DBS was performed for severe dyskinesia (n=5), "on/off motor" fluctuations (n=1) and medication-refractory tremor (n=3). The target symptoms were improved in all patients. Postoperatively, scores on the Unified Parkinson Disease Rating Scale Part II and III and subscores on Parkinson disease questionnaire-39 improved (P<0.05).
  
  
  CONCLUSIONS
  Although motor response to levodopa remains the primary selection criteria for DBS candidacy in Parkinson disease, patients who do not meet the 30% threshold and have disabling symptoms may still benefit from DBS. Select patients with severe dyskinesia, "on/off" motor fluctuations, and/or medication-refractory tremor may experience significant benefits from DBS and should be considered on a case by case basis through an interdisciplinary team evaluation.
authors: Department of Neurosurgery, College of Medicine/Shands Hospital. takashi.morishita@neurosurgery.ufl.edu
authors: Takashi
authors: T
authors: Morishita
authors: Maryam
authors: M
authors: Rahman
authors: Kelly D
authors: KD
authors: Foote
authors: Kyle M
authors: KM
authors: Fargen
authors: Charles E
authors: CE
authors: Jacobson
authors: Hubert H
authors: HH
authors: Fernandez
authors: Ramon L
authors: RL
authors: Rodriguez
authors: Irene A
authors: IA
authors: Malaty
authors: Dawn
authors: D
authors: Bowers
authors: Christopher J
authors: CJ
authors: Hass
authors: Yoichi
authors: Y
authors: Katayama
authors: Takamitsu
authors: T
authors: Yamamoto
authors: Michael S
authors: MS
authors: Okun
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000009:adverse effects*; D003131:Combined Modality Therapy; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007980:Levodopa / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000628:therapy*; D011788:Quality of Life; D012189:Retrospective Studies; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa