The Utility of Imaging Parameters in Predicting Long-Term Clinical Improvement After Shunt Surgery in Patients with Idiopathic Normal Pressure Hydrocephalus.

OBJECTIVE: It is difficult to predict which patients with idiopathic normal pressure hydrocephalus (iNPH) will improve after shunt surgery. This study investigated the association between preoperative imaging parameters in patients with iNPH and long-term outcome after shunt placement. METHODS: Patients with iNPH who showed a response to large-volume cerebrospinal fluid drainage and subsequently underwent ventriculoperitoneal shunt surgery were reviewed. Long-term patient-reported outcomes were obtained by telephone interview. Preoperative computed tomography and/or magnetic resonance imaging were retrospectively reviewed to determine associations between imaging parameters and clinical outcome. RESULTS: The final analysis included 37 patients. The median duration between shunt surgery and telephone interview was 30 months (range, 12-56 months). Gait improvement after shunting was present more often in patients without focally dilated sulci (95% vs. 71%, P = 0.04), but a statistically significant relationship was not established after logistic regression. Patients with cognitive improvement after shunting had a higher preoperative Evans index (mean 0.41 vs. 0.36, P < 0.01), and Evans index was a predictor of cognitive improvement (odds ratio = 1.40, scale of 0.01, P = 0.01). CONCLUSIONS: Higher Evans index is a predictor of long-term cognitive improvement after shunt placement; however, no cutoff value demonstrates sufficient accuracy for the selection of shunt candidates. None of the evaluated imaging features was predictive of long-term gait or urinary improvement. The utility of imaging to predict a response to shunting is limited, and no imaging feature alone can be used to exclude patients from shunt surgery.

The Subjective Experience of Patients Undergoing Shunt Surgery for Idiopathic Normal Pressure Hydrocephalus.

OBJECTIVE: The counseling of patients with idiopathic normal pressure hydrocephalus (iNPH) is difficult; there is variability in the diagnostic criteria, and a definitive diagnosis can be made only postoperatively. A patient's clinical response to shunting is also difficult to predict. This study examines the subjective experience of patients treated for iNPH, to identify the challenges patients face and to improve patient outcomes and satisfaction. METHODS: We reviewed a consecutive series of patients diagnosed with iNPH who underwent ventriculoperitoneal shunt surgery between January 2012 and March 2016 at our institution. Semistructured telephone interviews were conducted with 31 patients. Interviews were analyzed using the principles of grounded theory. RESULTS: Thirty-one patients who underwent shunt surgery for iNPH were interviewed to reach saturation of themes. Seven themes were identified: 1) long preoperative course causes morbidity; 2) the decision to have shunt surgery is easy to make; 3) patients primarily desire to gain independence; 4) patients show variable levels of anxiety; 5) comorbid conditions interfere with postoperative assessment; 6) patients stand by their decision to have shunt surgery; and 7) outside information is used before surgery. CONCLUSIONS: Patients often present to the neurosurgeon frustrated and desperate after a long preoperative course. It is important to acknowledge the uncertainty regarding diagnosis and response to shunting when counseling patients. Comorbid conditions interfere with the ability to assess progression of iNPH and the effectiveness of the shunt. Patient caregivers play a large role in decision making and clinical course and should be included when counseling patients.

Pretreatment predictors of adjuvant chemoradiation in patients receiving transoral robotic surgery for squamous cell carcinoma of the oropharynx: a case control study.

BACKGROUND: The purpose of this study was to identify preoperative patient characteristics associated with the incidence of positive surgical margins or lymph node extracapsular extension (ECE), which necessitate adjuvant chemoradiation after transoral robotic surgery (TORS). METHODS: We conducted a single institution retrospective study of 34 consecutive patients with primary oropharyngeal cancer who underwent TORS. All imaging was reviewed by a single neuroradiologist. Surgical margins and ECE status were determined by a single head and neck pathologist. Associations of preoperative patient characteristics with positive surgical margins and lymph node ECE were examined using univariate analysis. Independent predictors of these outcomes were determined using logistic regression. RESULTS: Preoperatively, the majority of patients had early-stage disease (7 cT1 and 21 cT2; 10 cN0). Positive margins occurred in 4 (12 %) patients. A clinically positive lymph node was seen in 23 (68 %) patients. Neck dissection was performed in 29 (85 %) patients, among whom 19 had a pathologically positive lymph node and 15 had nodal ECE. Logistic regression showed that larger preoperative lymph node size was an independent predictor of ECE (odds ratio, 13.32 [95 % CI, 1.46-121.43]). Among the 21 patients with a clinically positive lymph node who underwent neck dissection, ECE was present more often in patients with a preoperative node size ≥ 3.0 vs. < 3.0 cm (92 % vs. 44 %, P = 0.046). There was no patient characteristic associated with positive margins. CONCLUSIONS: Patients with a larger preoperative lymph node appear more likely to have ECE, and thus be treated with chemoradiation after TORS, with a potentially higher rate of toxicity. Lymph node size should be taken into account when deciding upon treatment approaches. Further research is needed to validate these results.