NeuroTalk Support Groups - Interpreting MRI

Hello Everyone, I have posted a couple other times, so I'll just give a quick overview of my TBI story: In a car accident January 2018. Did not physically hit head on anything, did not lose consciousness, but the impact and being thrust about left me diagnosed with a mild concussion. I experienced dizziness, heavy head, headaches, fogginess, sensitivity to light & sound for several weeks afterward (and subsequently lost my job due to this), but I felt like my symptoms were starting to improve.

But as of the past month, my symptoms have returned and morphed into extreme feeling of what I describe as a "poisoned brain" sensation; a deep-seeded "unwell" feeling that interferes with my daily life to the point where I have to skip out on some family events because my brain is too "overwhelmed" to handle driving or stimuli. This is off and on. I noticed that if I don't get enough sleep, that exacerbates it. Also, I unable to experience high emotional states without it causing this sickness. I laughed a lot the other day, and my brain paid for it; I almost felt like I couldn't function after that.

I had a second MRI, and now my doctor is suggesting I get a spinal tap, as he wants to check to see if maybe I have a spinal fluid leak/low pressure headaches. Everything I have read about this condition does not sound like my symptoms. I am scheduled to see him again to discuss this, as I am confused. And frankly, I do not want to unnecessarily get a spinal tap!

Is there anyone who is knowledgeable in interpreting MRI results, or would have any insight, in regards to why this spinal tap is being suggested? I feel this is unnecessary, but I still have no answers myself after 11 months of, what seemed to be at the time, a minor injury. Sorry for the lengthy post, and thank you very much for reading.

Here are the MRI results:

FINDINGS:

The inferior tonsillar tips end approximately 0.9 cm below the level of
the foramen magnum. However, there is no deformity of the inferior
tonsils or internal signal change of the tonsils or the cervicomedullary
junction. CSF of the foramen magnum is not effaced. There is mild
flexion of the neck.

Remaining gray and white matter is a normal appearing. Normal
parenchymal volume. No mass, mass effect, restricted diffusion, or
hemorrhage.

Ventricles are symmetric. No abnormal extra-axial fluid collection.
Basilar cisterns are symmetric. Major arterial and venous flow voids are
present.

Temporal air spaces and paranasal sinuses are essentially well aerated.
Limited evaluation of the orbits is unremarkable.