Rahul R Parikh1, Robert R Goodman2, Ryan Rhome3, Edward Sudentas4, Frieda Trichter4, Louis B Harrison5, Walter Choi4. 1. Department of Radiation Oncology, Mount Sinai Roosevelt Hospital, Mount Sinai Health System, Icahn School of Medicine at Mount Sinai, New York, New York. Electronic address: parikhrr@gmail.com. 2. Department of Neurosurgery, Mount Sinai Health System, Icahn School of Medicine at Mount Sinai, New York, New York. 3. Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, New York. 4. Department of Radiation Oncology, Mount Sinai Roosevelt Hospital, Mount Sinai Health System, Icahn School of Medicine at Mount Sinai, New York, New York. 5. Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida.
Abstract
PURPOSE: The purpose of this study was to assess the safety and outcomes of the clinical use of LINAC (linear accelerator)-based flattening-filter-free beams for delivering ablative stereotactic radiosurgery (SRS) for trigeminal neuralgia (TN). METHODS AND MATERIALS: Thirty-six consecutive patients (34 unique patients) followed up by a single neurosurgeon and diagnosed with medically refractory unilateral TN were treated with SRS. There were 14 left-sided cases (41%) and 20 right-sided cases (59%). Twenty-eight of the patients (82%) had type 1 TN, and 6 (18%) had type 2 TN. Previous treatments were as follows: 10 patients (29%) had SRS to the ipsilateral TN (8 with Gamma Knife, 2 with LINAC), 4 (12%) had percutaneous rhizotomy, and 3 (9%) had microvascular decompression. A median prescription dose of 75 Gy (range, 70-80 Gy), prescribed to the 100% isodose line, was delivered in a single fraction. Before treatment delivery, image guidance verified stereotactic frame placement, head position, and final isocenter. The volume of brainstem receiving ≥10 Gy was <0.5 cm(3). At each visit, patients prospectively reported outcomes using the Barrow Neurological Institute (BNI) pain scale. RESULTS: With a median follow-up of 3.1 months (range, 0.6-24.3; mean, 5.5 months), no patient experienced grade 1+ toxicities. There were no new episodes of dysesthesia, hypoesthesia, or long-term complications related to SRS. Median baseline (pre-SRS) BNI score was 5.0 (mean, 4.7). Clinical assessment at first follow-up (median, 1 month) demonstrated a median BNI score of 3.0 (mean, 3.1). When stratified by TN subtype, both type 1 and type 2 TN patients had a median BNI score of 3.0 at first follow-up. Thirty patients (88.2%) achieved a reduction in their BNI at their first follow-up, and 5 patients (15%) achieved a score <3, which represents medication-free pain relief. The median BNI at second follow-up (average, 6.3 months) was 2.5. CONCLUSIONS: We report our experience with modern LINAC-based SRS using flattening-filter-free beams for TN. This treatment appears to be a safe and effective technique, although longer follow-up is needed to confirm durability. This modality may prove to be a viable treatment alternative for TN.
PURPOSE: The purpose of this study was to assess the safety and outcomes of the clinical use of LINAC (linear accelerator)-based flattening-filter-free beams for delivering ablative stereotactic radiosurgery (SRS) for trigeminal neuralgia (TN). METHODS AND MATERIALS: Thirty-six consecutive patients (34 unique patients) followed up by a single neurosurgeon and diagnosed with medically refractory unilateral TN were treated with SRS. There were 14 left-sided cases (41%) and 20 right-sided cases (59%). Twenty-eight of the patients (82%) had type 1 TN, and 6 (18%) had type 2 TN. Previous treatments were as follows: 10 patients (29%) had SRS to the ipsilateral TN (8 with Gamma Knife, 2 with LINAC), 4 (12%) had percutaneous rhizotomy, and 3 (9%) had microvascular decompression. A median prescription dose of 75 Gy (range, 70-80 Gy), prescribed to the 100% isodose line, was delivered in a single fraction. Before treatment delivery, image guidance verified stereotactic frame placement, head position, and final isocenter. The volume of brainstem receiving ≥10 Gy was <0.5 cm(3). At each visit, patients prospectively reported outcomes using the Barrow Neurological Institute (BNI) pain scale. RESULTS: With a median follow-up of 3.1 months (range, 0.6-24.3; mean, 5.5 months), no patient experienced grade 1+ toxicities. There were no new episodes of dysesthesia, hypoesthesia, or long-term complications related to SRS. Median baseline (pre-SRS) BNI score was 5.0 (mean, 4.7). Clinical assessment at first follow-up (median, 1 month) demonstrated a median BNI score of 3.0 (mean, 3.1). When stratified by TN subtype, both type 1 and type 2 TN patients had a median BNI score of 3.0 at first follow-up. Thirty patients (88.2%) achieved a reduction in their BNI at their first follow-up, and 5 patients (15%) achieved a score <3, which represents medication-free pain relief. The median BNI at second follow-up (average, 6.3 months) was 2.5. CONCLUSIONS: We report our experience with modern LINAC-based SRS using flattening-filter-free beams for TN. This treatment appears to be a safe and effective technique, although longer follow-up is needed to confirm durability. This modality may prove to be a viable treatment alternative for TN.
Authors: Aldo Berti; George Ibars; Xiaodong Wu; Alex Sabo; Michelle Granville; Gail Suarez; James G Schwade; Robert E Jacobson Journal: Cureus Date: 2018-05-09
Authors: Richard A Popple; Xingen Wu; Ivan A Brezovich; James M Markert; Barton L Guthrie; Evan M Thomas; Markus Bredel; John B Fiveash Journal: Adv Radiat Oncol Date: 2018-03-02