Much further back… Abraham Lincoln was a Republican. The party was founded on anti- slavery. The current party has nothing to do with the original party.
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5 year old patient with 1 week of right eye blurry vision, then several days of right eye pain. Physical exam notable for right papilledema and progressively worsening vision.
MRI postcontrast through the orbits shows an enlarged, hyperenhancing right optic nerve (red arrow) compared to the normal left side (green arrow), compatible with optic neuritis.
A lumbar puncture was performed: no oligoclonal bands, no aquaporin 4 IgG, positive anti-MOG. The patient was treated with prednisone with return to normal vision a few months later.
Final diagnosis: optic neuritis from myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).
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This patient had episodic electric/shooting/radiating pain of the left face. An MRI was done.
[Top]: Axial heavily T2-weighted image (bright = CSF, dark = not CSF) at the level of trigeminal nerve (cranial nerve V / CN5), shows a normal right CN5 (green). The left CN5 seems to be splayed out by another tubular structure (red), which is the superior cerebellar artery (SCA).
[Bottom Left]: Sagittal reconstruction of the normal right CN5 (along the blue line).
[Bottom Right]: Sagittal reconstruction of the left CN5 shows the left SCA contacting the left CN5. The close proximity of the left SCA and its arterial pulsations likely irritate the cranial nerve, which is the primary sensory nerve of the face, causing trigeminal neuralgia.
No they don't all calcify.
The tumor here is growing from the bone and destroying it. The normal bone cells are trying to repair by making more bone. If faster the tumor destroys and grows, the less smooth the repaired bone can look.
Yeah they can decompress by removing part of the back of the skull so there’s more space.
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Incidental finding of a superior lumbar hernia (Grynfeltt-Lesshaft hernia). In this case, only a lobule of retroperitoneal fat is herniating through the defect, but organs can also herniate through.
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Continuing the theme of things extending into spaces they don't belong in, this is an incidental finding of an inguinal hernia that contains a small portion of the bladder. The patient got the CT for other reasons.
Bowel into inguinal hernia causing bowel obstruction.
Appendix into inguinal hernia, incidental finding.
Ventriculoperitoneal shunt into inguinal hernia, incidental finding.
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[LEFT]: This patient had one of the longer cerebellar tonsillar herniations I've seen. The tonsil is peg-like in shape and extends quite far below the foramen magnum to the level of the C2 posterior arch. As a result, there is crowding at the foramen magnum that is enough to impede CSF flow, resulting in hydrocephalus with dilated ventricles. Partly seen in the cervical cord from C2 and below is a syrinx, an associated finding. Chiari I is thought to be due to not enough space provided for the cerebellum by the calvarium or skull base shape, causing it to herniate into the spinal canal and cause trouble.
[RIGHT]: A comparison normal from online for you to compare the cerebellar tonsils.
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[LEFT]: The midbrain has a deep interpeduncular cistern, and the superior cerebellar peduncles are very prominent and elongated, making the brainstem at this level look like a molar tooth. This is a classic finding in Joubert syndrome.
[RIGHT]: A comparison "normal" midbrain. However, this patient's brain is not normal at all. Can you find the abnormalities?
Answer
Compare the left and right temporal lobes in [RIGHT] to the [LEFT] image. Look at how many more gyri and sulci there are in the [LEFT] image. The [RIGHT] patient has a diffuse pachygyria (abnormally reduced brain gyrations). Both Joubert syndrome and pachygyria arise from failure of neurons to migrate, although the genes involved and underlying mechanism are different between the two. (NB: Pachygyria is just a descriptive term for less than normal number of gyri, which can be from a large number of causes mostly having to do with abnormal neuron migration.)
It's called periosteal reaction. Here's a few examples I posted already: one, two.
Hi. Try to match the outline of the humerus to that on the radiograph. Then the big bright mass to the right of the humerus (going by the picture) is the cancer. Now see if you can make out the rough outline of it on the radiograph.
The cloudiness you're seeing is calcification within the tumor. Specifically, the outward "tendrils" (as someone else called it) exploding out from the margin of the humerus is really aggressive periosteal reaction, which I've posted a few examples before already: one, two.
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Female in her 30s with painful left shoulder.
[Left]: X-ray shows a mass arising from the left proximal humerus and extending into the adjacent shoulder soft tissues with really aggressive periosteal reaction ("hair on end"). The proximal humerus itself is also heterogeneous with lucent areas. The lateral surface of the upper humerus shows "saucerization," where the cortex is thinned out and looks like a saucer seen on edge.
[Middle]: MRI IR sequence shows a hyperintense bony mass with large soft tissue component.
[Right]: MRI postcontrast T1 IDEAL shows that the mass is enhancing.
This turned out to be high-grade surface osteosarcoma.
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33 year old female with abdominal pain, abdominal distention, nausea/vomiting, early satiety, and weight loss.
Bottom right: Ultrasound done in a panorama shows how distended the abdomen is by a large multi-cystic mass.
Top right: Non-panoramic ultrasound image shows how limited the imaging modality is in being able to cover such a large mass. This image also shows a more solid area within the mass.
Left: CT images approximately where the ultrasound was done.
The patient underwent laparotomy with removal of the ovarian, fallopian tube, and appendix. There was a large ovarian cyst that was draining serous fluid (watery), mucinous fuid (mucus-like), and blood. The final path was as titled.
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Postcontrast imaging of 2 patients with glioblastoma. These tumors are notorious for spreading along the white matter tracts - in this case the transverse fibers of the corpus callosum, given them a classic "butterfly" appearance.
I think while the general communities have made it, a lot of niche communities failed to attract enough population to keep on generating more content. As an example, just search for the "Imaginary" series of landscape art communities on the Fediverse (eg. ImaginaryVistas). Many of them don't have any recent posts or 1 post per days or weeks. That's not enough to keep people invested. Even the largest digital art community is still mostly carried by 1 person.
The Lord said that the "VCR shall be saved" with the knife technique, but in the following paragraph, it was not the VCR that was saved, but the man that was saved. The VCR was not saved!
Developmental delay, seizures, cerebral palsy, autism, depending on severity.
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Two different patients with genetic disorders resulting in overgrowth of the brain.
These represent mutations in cell cycle and cell metabolism genes that lead to larger cells and/or more cells. These types of disorders tend to have mosaicism of some form, which is to say some cells have the mutation active while others don't. The distribution of these cells can be very geographic/regional - in these two cases, one hemisphere of the brain is involved.
Compare this against a previous case with hemispheric atrophy.
It's usually barium sulfate, which can have a more viscous consistency that makes it go down a little slower and allows it to stick to things to outline them. But yes, regular iodine contrast can also be used.
Yep. They're in the middle of swallowing some liquid contrast. Take the picture 1 second later and you miss the shot.
It looks like it could fall over with any gust of wind and kill someone.
Hello everyone!
I am amazed at how quickly this rather specialized community has grown. It gives me perverse pleasure to see that C/Radiology has somehow exceeded C/Medicine in subscriber numbers! So thanks for visiting and allowing me to share my interest in this field with you!
As the community has expanded, we have, of course, come across typical growing pains, and since this is a medical community, some additional factors must also be considered, such as respect for any patient discussions and medical privacy. We have the potential for a lot more growth, but we must be vigilant in respecting medical laws as well. To that end, I have made additional changes to the Community Rules to better clarify the situation for everyone. Additionally, I have conversed with the Lemmy.World admins, who are supportive of this community and now aware of its unique characteristics and requirements.
One major change that has come out of that discussion is that we worry about how inadvertent posts that breach patient confidentiality would behave with federation. It's not like Reddit, where the post is centralized, and there's only one copy to remove. As a consequence, for now, I have changed this community to only allow moderators to post. My hope is that, in the not-too-distant future, Lemmy itself will implement a way for users to post pending moderator approval. Visitors may still comment upon any posts in this Community, and so as a workaround, I've started this megathread for any general questions or discussions you might have regarding radiology. (Please follow the rules still!) If you would like to share a case as a post - please DM me, and I will post on your behalf.
Now onto future updates: For the next few weeks, I will have reduced posting - because I'm going to be away from steady internet. I will continue to post interesting cases I come across thereafter. Eventually, I also plan to have a sticked general guidance on how to look at radiologic images so that you can have a better understanding and capability of looking at these images yourself!
While we're at it, I'm also looking for additional mods to help. I would prefer that you have some medical imaging background, medical background in general, or moderator experience if possible!
Should the instances that responded to you be refederrated? I’m pretty sure I saw some of them on lemmy.world’s block list. I think it would be sad for these small servers to not realize they are, in fact, not connected to the greater fediverse. On the other hand, if you’re an admin, and you don’t know what you’re doing to the point of not knowing your server was infected by hundreds of thousands of bots, maybe it’s too dangerous to refed.
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Quick one today. Take a look at Patient A and Patient B.
Patient A has a smooth focal indentation of the posterior cervical esophagus.
Patient B has a broader indentation that is also irregular and nodular along its contour.
Patient A has a cricopharyngeal bar, which is a prominence caused by the cricopharyngeus muscle that can cause dysphagia if it gets really prominent. Patient B has esophageal squamous cell carcinoma.
I think these are valid concerns, once again, and must be discussed and hashed out so that everyone is on the same page.
The medical field has a long history of sharing cases for education, and I would say radiology definitely is one of the fields where this is done more often than not, due to the complexity of cases, use of imaging, which is a format that makes it easier to share. I would also say that radiology is quicker to embrace new technologies, including use of the internet and social media, due to reliance on technology to begin with. For example, you can find on twitter, of all places, many case presentations and discussions, many by prominent leaders in the field. Almost all the major radiology societies have some case series for perusal, there’s Radiopaedia as I already mentioned, and the largest community I’m aware of is r/radiology, which I modeled this community after.
I understand there’s a slippery slope between posting educational content and entertainment content. I intend to firmly keep us away from the entertainment side. While I do not want this community to fall into a somber tone, I will not tolerate posts or comments intended to mock or demean a case/patient.
In regards to data harvesting - interesting thought. I had to dig a little bit. There’s definitely been some publications that deal with large medical imaging datasets wherein AI was able to use the high resolution imaging to identify patient features, including 3D reconstruction of the face from the data. The images posted here are: 1) regular .jpgs and not high resolution files like dicom, 2) limited to a couple of images when a full CT can be in the hundreds, and 3) been through photoshop, powerpoint, possibly multiple saves though jpg with degradation each time, or they’re crappy phone camera images of a medical image. I can’t say the risk is absolutely 0, but it’s pretty close - by staying within medical privacy laws and avoiding super rare presentations of things.
However, your concerns have been my concerns too, so I have also reached out to the .world admins for their thoughts. Perhaps they don’t feel comfortable hosting this type of content, or would like to see some other assurances. I will find out and proceed from there.
Yes that's correct, it's the levamisole that presented as demyelination in this case.
Cocaine by itself can also cause problems, which I would categorize in 3 ways:
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Sudden-onset issues that are potentially life-threatening. Cocaine is a stimulant, which can raise blood pressure, heart rate, etc. Those effects can cause ischemic stroke, hemorrhagic stroke, rupture of pre-existing aneurysms (with subsequent intracranial hemorrhage), and seizures, all of which can show up on brain imaging.
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Long-term issues. These are insidious, subtle changes from repeated use of cocaine, which will damage the brain through neurotoxicity + the long-term results of an accumulation of events from #1.
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Complications from cocaine use. I would put levamisole in this category. For other drugs that are more commonly injected (rather than snorted or smoked), brain infections from use of dirty needles would also go into this category.
Thank you for this comment, because it brings up some very important issues, which I hope this reply addresses.
The biggest issue is the matter of patient confidentiality. This is of utmost concern in an online medical community, especially one wherein clinical vignettes are presented. I take extreme care to avoid including any information that can narrow down to a patient, thus breaching confidentiality. Similarly, I expect anyone else commenting or posting here to follow this rule, Rule 4, which was created not just for internet etiquette but literally to prevent illegal breaches of confidentiality. With regards to consent - this is not required for publishing de-identified information, or sites like Radiopaedia with their thousands of cases would not exist. With regards to patient confidential information that cannot be shared - this not only includes the obvious ones such as patient age, DOB, dates of events, addresses, etc etc, but also vaguer information. For example, there are cases that I would never present here online because the disease is so incredibly rare that the disease itself becomes a patient identifier. These types of cases I would formally publish in the literature if need be. For this particular case, I do not think the information presented breaks these rules (or I would not have posted). Cocaine use is fairly common among the demographic in question, and being found in the shower is not that uncommon, although dramatic.
Second, to address the following:
The title is like your a friend but the text is from a medical professional.
This is something that I have been struggling with. This community is growing at an exceptional rate, and visitors seem to be overwhelmingly from a non-medical background. There are comments that frankly say they do not understand certain things, and other comments and questions imply a lack of experience with looking at imaging studies. I have been vacillating between using terminology and sentences that laypeople can understand versus maintaining medical terminology. I think this is why you think I am writing about a friend in the title, but the body of the post is more medically-oriented. For this reason, I have changed the title - it did not need to be so dramatic. In the future, I will be more careful with my wording.
Please let me know if this addresses your concerns. I would also love to hear more input regarding point #2. Should I continue to word cases as if talking to other medical professionals or include more basic terminology so that the general public can understand? The purpose of these cases, and this community in general, is to be an educational resource in terms of what Radiology is and does.
This complication of cocaine use generally manifests as a single episode of demyelination that recovers well with treatment. Of course, the long term depends on how often the cocaine abuse happens.
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Patient was a young adult working in finance at a major tech company found to be mute and diaphoretic.
Physical exam notable for fever, tachycardiac, hypertension, awake but not following commands, aphasic, and with hyperreflexia and muscle ridigity. CK peaked to 11,344.
MRI shows multiple ovoid to splotchy confluent lesions in the white matter with diffusion restriction. Lesions also enhanced with hyperperfusion (not shown).
Urine drug test positive for cocaine. Infectious work-up was negative. Steroids were started with good recovery.
Patient denied knowingly taking cocaine but did say weekly use of what they thought was MDMA with friends...
Final diagnosis: Levamisole-induced leukoencephalopathy. Levamisole is an antiparasite medication that is no longer used in the US but still in some other countries. It is a common cutting agent in cocaine. It's neurotoxic effects primarily come from causing demyelination.
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I remember this episode quite well because it happened around the time I decided to get into the medical field. In the episode, a young teacher had a first-time seizure while in the middle of teaching. House and team attempted to get a brain MRI, but she got an allergic reaction from the IV contrast. Thereafter, some drama happens, and at some point, they break into her house, find out she's been eating raw pork (wtf?), and diagnose her with the tapeworm infection associated with eating raw pork, cysticercosis (and neurocysticercosis, since it also involved her brain). They took an x-ray of her leg to show all the parasites in the muscles, and then House scolds her for being stupid. I remember thinking that was such as crazy medical story.
The reality is - they could have just repeated the brain MRI minus the contrast part, and the radiologist would have been able to identify neurocysticercosis without issue. House would have complained to Cuddy that she really was wasting his time with these basic cases, and the episode would have lasted 15 minutes tops...
Anyhow, this is a 25 year old Hispanic from jail. Just like the House episode, he presented with first time seizure and headaches.
CT of the head [top] shows a cystic lesion in the left frontal lobe. If one pays attention, one can see a small dot (blue arrow) within the cyst representing the scolex of the tapeworm parasite. Just from the CT appearance, history of seizure, and risk factors of jail (the parasite thrives in areas of low sanitation) and Hispanic (the parasite is endemic to South America), neurocysticercosis is the top possibility. A differential diagnosis of cystic brain tumor is provided to complete the picture.
MR [middle and bottom] shows a cystic lesion again. After giving IV contrast [middle right], one can see the cyst has a thin wall of enhancement (teal arrows). On T2 [bottom left] and especially FLAIR [bottom right], one can see a rim of swollen brain (green arrows) from the inflammation going on around the parasite.
This was diagnosed as neurocysticercosis in the colloidal vesicular stage and antiparasite medication was started.
Oh good to know. I guess I only really caught reddit downtimes in the past.
I like how it looks exactly like reddit's status page, especially considering they just released old.lemmy.world.
Just a standard T2 sequence.
FLAIR would have dark CSF, since that's what FLAIR is designed to suppress - CSF.
MPRAGE is a T1 sequence that's usually done with contrast.
Thank you! Much appreciated.
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[Top]: X-ray shows a lucent, bubbly, lesion of the distal femur at the metaphysis. On the frontal view [top right], there is breakage through the medial femoral cortex into the adjacent soft tissues, not a good sign.
[Bottom]: MRI shows a multicystic lesion filling the distal femur containing multiple locules, many with fluid-fluid, fluid-debris, and fluid-hemorrhage levels. The most common lesions with this striking appearance are aneurysmal bone cyst, giant cell tumor, or telangiectatic osteosarcoma. Unfortunately, there is clearly extension of the bone tumor beyond the bone (yellow arrows), which favors a more aggressive neoplasm from that differential diagnosis - this turned out to be telangiectatic osteosarcoma.
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5 year old who fell off a slide.
Initial imaging shows a comminuted fracture through the distal humerus, compatible with a supracondylar fracture. Nothing else appreciable here, except maybe in retrospect some lucency of the distal humerus where the fracture is.
4- and 7-month follow-up radiographs shows a growing lucent lesion of the distal humerus, expanding the bone there. It has a multicystic appearance. A diagnosis of large simple bone cyst versus aneurysmal bone cyst was proposed.
12 month follow-up was done after the cyst was opened surgically, its contents scraped off, and the resulting cavity was packed with allograft bone chips. At surgery, this turned out to be an aneurysmal bone cyst.
5 year follow-up shows involution of the cyst cavity with some residual heterogeneity and a bone spur at the anterior aspect of the distal humerus.
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[Left]: Head CT shows left hemispheric volume loss. The injury happened early enough that even the skull is smaller on that side.
[Right]: Brain MRI shows the severe left hemispheric atrophy. Some of the brain gyri have bulbous ends and a thin neck, resembling mushrooms, a shape called ulegyria and consequence of the brain atrophy. The left lateral ventricle is mildly enlarged due to the atrophied brain.
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Red arrows point to 2 big gallstones, top one in the gallbladder and bottom one obstructing a small bowel loop, and a small gallstone in the cystic duct.
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Red lines point to hernia entry. Red arrow points to where the bowel tapers and becomes obstructed as it enters the hernia sac.
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[Left]: Fetal MRI (FIESTA sequence) shows twins joined from their lower chest to the pelvis, but truly fused and sharing a single abnormal pelvic region. Not shown, but there are 3 lower limbs - one of the twins only had a single lower extremity.
[Right]: Postnatal small bowel follow-through (SBFT). It was unclear initially whether the twins shared a single rectum or had their own rectum. Therefore, contrast was administered via nasogastric tube for the twin with the suspected nonfunctional rectum, and serial imaging was performed until it passed into what turned out to be a separate, functional, but small rectum/anus.
I do not know too much about conjoined twins - not my area of expertise, but the general forms to consider are the side of fusion: ventral (front to front), lateral (side to side), dorsal (back to back), or caudal (tail end to tail end). Within these first 3, there are subtypes depending on how far up the fusion goes (head, chest, abdomen/pelvis); by definition, the caudal version obviously is only a lower body fusion. Once this is derived, an additional classification is the number of upper and lower limbs.