Minor artifacts update

Author: agentmess

Notebooks/Artifacts.ipynb

@@ -48,7 +48,6 @@
    ]
   },
   {
-   "attachments": {},
    "cell_type": "markdown",
    "metadata": {},
    "source": [
@@ -58,17 +57,23 @@
     "\n",
     "| Artifact Name | Source | Appearance | What to do? | Frequency or Phase encoding |\n",
     "|---|---|---|---|---|\n",
-    "| Aliasing | Sequence - FOV too small, or parallel imaging failed | Signal folds across image | Increase FOV, swap PE/FE, reacquire sensitivity maps (parallel imaging) | Phase encoding |\n",
-    "| Gibbs Ringing/Truncation | Sequence - due to Fourier encoding of edges | Ripples/ringing at sharp edges | Filtering of data | N/A |\n",
-    "| Boundary Artifacts/Partial Volume | Sequence and Sample - opposite $M_{XY}$ phases with a voxel due to inversion or chemical shift | Artificial dark lines at tissue boundaries  | fat suppresion, fat/water imaging | N/A |\n",
-    "| Motion/Flow | Sample - signal modulated during spatial encoding | Copies or \"Ghosts\" of image regions that are changing due to motion or flow | Breath-hold, gating, triggering, flow compensation, swap PE/FE | Phase encoding |\n",
-    "| Image Displacement/Distortion | Sample - chemical shift (fat) and off-resonance (e.g. magnetic susceptibility differences)  | Shifts in image  | Increase bandwidths, shimming, fat suppression, fat/water imaging, swap PE/FE |  Frequency encoding (2DFT), Phase encoding (EPI) |\n",
-    "|  Slice Displacement | Sample chemical shift (fat) and off-resonance (e.g. magnetic susceptibility differences)  | Slice location shifts  | Increase RF bandwidth, shimming, 3D | N/A | \n",
-    "| T2* | Sample - magnetic suscpetibility differences (e.g. implants, air) | Signal loss  | Spin-echo, shimming | N/A |\n",
-    "| Dielectric Shading | System - RF propogates unevenly, creating B1 inhomogeneity | Shading across entire image, particularly large FOV, higher B0 | B1-insensitive pulse sequences (e.g. adiabatic pulses), image bias correction | N/A |\n",
-    "| RF interference/Zipper | System - unwanted RF signal in data | Line of noisy signal on top of image | RF shielding (close door), check RF hardware, check room lights | At a specific frequency encoding location |\n",
+    "| Aliasing | Sequence - FOV too small, or parallel imaging failed | Signal folds across image | Increase FOV, swap PE/FE, reacquire sensitivity maps or reduce acceleration factor (parallel imaging) | Phase encoding |\n",
+    "| Gibbs Ringing/Truncation | Sequence - due to Fourier encoding of edges | Ripples/ringing at sharp edges | Filtering of data, decrease voxel size | N/A |\n",
+    "| Boundary Artifacts/Partial Volume | Sequence and Sample - opposing phase of $M_{XY}$ within a voxel due to inversion or chemical shift | Artificial dark lines at tissue boundaries  | fat suppresion, fat/water imaging, change inversion time | N/A |\n",
+    "| Motion/Flow | Sample - signal modulated during spatial encoding | Copies or \"Ghosts\" of image regions that are changing due to motion or flow | Breath-hold, gating, triggering, flow compensation, spatial saturation, swap PE/FE | Phase encoding |\n",
+    "| Image Displacement/Distortion | Sample - chemical shift (fat) and off-resonance (e.g. magnetic susceptibility differences)  | Shifts of tissue signals in image, pile-up and stretch artifacts  | Increase bandwidths, shimming, fat suppression, fat/water imaging, swap PE/FE |  Frequency encoding (2DFT), Phase encoding (EPI) |\n",
+    "|  Slice Displacement | Sample - chemical shift (fat) and off-resonance (e.g. magnetic susceptibility differences)  | Slice location shifts  | Increase RF bandwidth, shimming, use 3D scanning | N/A | \n",
+    "| T2* | Sample - magnetic suscpetibility differences (e.g. implants, air) | Signal loss  | Use spin-echoes, shorten TE, shimming | N/A |\n",
+    "| Dielectric Shading | System - RF propogates unevenly, creating B1 inhomogeneity | Shading across entire image, particularly with large FOVs and higher B0 | B1-insensitive pulse sequences (e.g. adiabatic pulses), image bias field corrections | N/A |\n",
+    "| RF interference/Zipper | System - unwanted frequencies received in data | Line of noisy signal on top of image | RF shielding (e.g. close door), check RF hardware, check room lights | At a specific frequency encoding location |\n",
     "| Gradient non-linearity | System - magnetic field gradients are not linear, especially away from isocenter | Distortion of subject, particularly near edges of large FOV | Gradient warping correction | N/A |\n",
-    "| Spike Noise | System - intermittent unwanted signal | Specific spatial frequency on top of entire image | check RF hardware (loose connections, broken components) | N/A |\n"
+    "| Spike Noise | System - intermittent unwanted signal | Specific spatial frequency on top of entire image | check RF hardware (loose connections, broken components) | N/A |\n",
+    "\n",
+    "<!-- Potentially add:\n",
+    "Eddy currents and gradient delays\n",
+    "Magic Angle\n",
+    "Overflow/ADC overrange\n",
+    "Time-of-flight (entry slice)>"
    ]
   },
   {