1. Detection of Botulinum Toxin Muscle Effect in Humans Using Magnetic Resonance Imaging: A Qualitative Case Series
- Author
-
Jonathan P. Dyke, Douglas Ballon, Gaurav Telhan, Mark Villanueva, Jaclyn Nestor, Keith Hentel, Michael W. O'Dell, and Carly Creelman
- Subjects
Male ,030506 rehabilitation ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Physical Therapy, Sports Therapy and Rehabilitation ,computer.software_genre ,Injections, Intramuscular ,03 medical and health sciences ,0302 clinical medicine ,Tibialis anterior muscle ,Voxel ,medicine ,Humans ,Botulinum Toxins, Type A ,Muscle, Skeletal ,Saline ,Stroke ,Aged ,Soleus muscle ,medicine.diagnostic_test ,business.industry ,Rehabilitation ,Stroke Rehabilitation ,Reproducibility of Results ,Magnetic resonance imaging ,Fascia ,Middle Aged ,medicine.disease ,Botulinum toxin ,Magnetic Resonance Imaging ,Surgery ,medicine.anatomical_structure ,Neurology ,Neuromuscular Agents ,Female ,Neurology (clinical) ,0305 other medical science ,Nuclear medicine ,business ,computer ,030217 neurology & neurosurgery ,medicine.drug ,Follow-Up Studies ,Muscle Contraction - Abstract
Background Although important for dosing and dilution, there are few data describing botulinum toxin (BT) movement in human muscle. Objective To better understand BT movement within human muscle. Design Proof-of-concept study with descriptive case series. Setting Outpatient academic practice. Participants Five subjects with stroke who were BT naive with a mean age of 60.4 ± 14 years and time poststroke of 4.6 ± 3.7 years. Methods Three standardized injections were given to the lateral gastrocnemius muscle (LGM): 2 contained 25 units (U) of onabotulinumtoxinA (Botox) in 0.25 mL of saline solution and the third 0.25 mL of saline solution only. The tibialis anterior muscle (TAM) was not injected in any subject. A leg magnetic resonance image was obtained at baseline, 2 months, and 3 months later with a 3.0 Tesla Siemens scanner. Three muscles, the LGM, lateral soleus muscle (LSM), and TAM, were manually outlined on the T2 mapping sequence at each time point. A histogram of T2 relaxation times (T2-RT) for all voxels at baseline was used to calculate a mean and standard deviation (SD) T2-RT for each muscle. Botulinum toxin muscle effect (BTME) at 2 months and 3 months was defined as a subject- and muscle-specific T2-RT voxel threshold ≥3 SD above the baseline mean at or near BT injection sites. Main Outcome Measures BTME volume for each leg magnetic resonance imaging slice at 3 time points and 3 muscles for all subjects. Results One subject missed the 3-month scan, leaving 18 potential observations of BTME. Little to no BTME effect was seen in the noninjected TAM. A BTME was detected in the LGM in 13 of 18 possible observations, and no effect was detected in 5 observations. Possible BTME effect was seen in the LSM in 3 subjects due to either diffusion through fascia or needle misplacement. Volume of BTME, as defined here, appeared to be substantially greater than the 0.25-mL injection volume. Conclusions This descriptive case series is among the first attempts to quantify BTME within human muscle. Our findings are preliminary and are limited by a few inconsistencies. However, we conclude that use of magnetic resonance imaging to detect the volume of BTME is feasible and may assist researchers in modeling the spread and diffusion of BT within human muscle. Level of Evidence IV
- Published
- 2016