Does it work!

In a recent issue of JAMA, there is an editorial of whether injection therapy for low back pain works. An evaluation of previous randomised trials and a meta-analysis shows that there is no clinically significant evidence that this works. And yet, we have an entire new field of pain management populated by anesthesiologists in particular but also radiologists and orthopedic surgeons, who specialise in injecting into the epidural space, facets and foramina. A cursory Pubmed review will show a large number of articles on this subject discussing technique and the value of one particular steroid over another….when in reality the efficacy of the very concept of injecting in the spine for pain management is questionable.

This is similar to the vertebroplasty controversy that still really hasn’t died, but for all practical purposes has been subverted by those who practice vertebroplasty so that the procedure can continue to be used across board.

The New York Times last week published a blog based on a recent article in the Mayo Clinic Proceedings that showed how doctors continue to use procedures and therapies that may be ineffective or may even harm patients. This is either due to ignorance or inertia, but in the period that the practice continues, harm continues to be done.

While all of us itch to “do something” each time a patient has a problem, we should constantly be asking ourselves, whether the procedures we perform and the therapies we use, actually work!

When Procedures Make Intuitive Sense, Despite the Data (or Lack of)…About IVC Filters and Vertebroplasty

Today’s (April 08, 2013) issue of JAMA Internal Medicine brings forth a new controversy regarding another common and popular interventional radiology procedure  – retrievable IVC filter placement.

A review of data in a new retrospective study on the efficacy of IVC filters, has shown that there is only one randomized control trial published in 1998 that showed a reduction in the rate of symptomatic pulmonary embolism in those with filters but with no significant long-term difference in the death rate at 8 years and with an increase in the rate of deep vein thrombosis in those who had filters.

This new retrospective study published in JAMA Internal Medicine concludes, “that the use of IVC filters for prophylaxis and treatment of venous thrombotic events, combined with a low retrieval rate and inconsistent use of anticoagulant therapy, results in suboptimal outcomes due to high rates of venous thromboembolism”

Another study in the same issue discusses the differing rates of use of this technique in California, the main factor being the particular hospital that is providing care. The Society of Interventional Radiology guidelines [4] for the use of an IVC filter list four absolute indications – “recurrent VTE (acute or chronic) despite adequate anticoagulation, contraindication to anticoagulation, complication of anticoagulation, inability to achieve/maintain therapeutic anticoagulation”.  However there is a long list of relative indications with little consensus and that is where there is significant variability, depending on the aggressiveness of the program.

It happened with vertebroplasty when two studies by Kallmes et al and Buchbinder et al, comparing sham procedures with actual procedures showed no significant difference in pain scores between the two groups at all time points. This kicked up a huge storm in the interventional radiology and spine communities, but also forced us to examine our data more objectively and spurred more hospitals and groups to perform their own double-blind control studies, a few of which like the Vertos II trial, have shown that vertebroplasty is better than controlled medical treatment, though there has been no comparison with sham procedures since the 2009 studies.

We all want to believe that “doing” something that is intuitive (cement in an acute fracture, IVC filter stopping downstream emboli) has to help, just like Dr. Zamboni’s belief in treating patients with multiple sclerosis by dilating areas of venous narrowing because of the theory he ascribes to that chronic cerebrospinal venous insufficiency is the cause of multiple sclerosis.

Procedures sometimes quickly become mainstream without data, simply because “they make sense”. Cardiac CT angiography found adopters in patients and celebrities like Oprah Winfrey, simply because it made sense to see the coronary arteries without a catheter, despite the lack of any kind of initial data.

In the end though, we as radiologists need to create compelling stories for the use of techniques, modalities and procedures by making sure that there are enough controlled studies that demonstrate efficacy and safety.

Hopefully in the near to medium future, there will be more date regarding the efficacy (or not) of IVC filters that will clear the air and help patients and the treating doctors make better decisions.

Brittle Bones, Late Diagnosis

I received a call about 4 months ago from a family physician, who wanted me to perform a USG or CT guided biopsy for a mass in the anterior compartment of the right thigh in a 47-years old woman. He did not give me any more details and said the patient would get in touch with me.

I forgot about this, until a month later, when I was going through some histopathology reports of biopsies done by my ultrasonologist and chanced upon a report that described a hemangiopericytoma in the thigh with a comment saying that this was consistent with a phospaturic mesenchymal tumor.

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Fig. 1: Ultrasound shows the mass in the anterior compartment of the right thigh (red arrow) with the biopsy needle (blue arrow)

I called for more details and then realized that this was the same patient that the family physician, a month ago, had called about. Different people in our department do ultrasound and CT-guided biopsies and the patient went straight to the ultrasonologist, who in turn, went ahead and performed a core biopsy of the mass in the anterior compartment of the thigh (Fig. 1).

A phosphaturic mesenchymal tumor is a rare condition and typically secretes FGF-23 (fibroblastic growth factor) that produces osteomalacia. This combination is called oncogenic osteomalacia or tumor-induced osteomalacia (TIO).

I then asked the patient to get all the reports and details.

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Fig. 2: Radiograph shows an insufficiency fracture (arrow) of the base of the proximal right 3rd metatarsal bone.

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Fig. 3: Radiograph shows an insufficiency fracture (arrow) of the mid-left 5th metatarsal bone.

It had taken 5 years to get to this diagnosis. She started with an insufficiency fracture, five years ago, in the right 3rd metatarsal bone (Fig. 2), followed a month later by another fracture in the left 5th metatarsal bone (Fig. 3). She received symptomatic treatment and went from doctor to doctor with variable diagnoses of osteoporosis and perhaps osteomalacia.

This went on for 4 years, until one day, she was unable to get up from bed. She was admitted to a hospital and a skeletal survey showed fractures of the necks of both humeri (Fig. 5) and femurs (Fig. 6) with biconcave vertebrae (Fig. 7). Finally she received a diagnosis of osteomalacia and was worked up.

Her serum calcium was normal, vitamin D was normal, serum phosphorus was very low and her 24-hours urine phosphorus was elevated with a normal serum parathormone level and a raised serum alkaline phosphatase level. She did not fit into vitamin D related causes or phosphate deficiency conditions and what was left was a potential diagnosis of oncogenic osteomalacia.

Fig 4

Fig. 4: Radiographs of both shoulders show fractures (red arrows) of the necks of both humeri

Fig 5

Fig. 5: Radiograph of the bones of the pelvis and both hips show fractures (red arrows) of the necks of both femurs.

Lateral radiograph of the spine shows biconcave vertebrae

Fig. 6: Lateral radiograph of the spine shows biconcave vertebrae

Thus started the search for an FGF-secreting tumor that produces phosphaturia, hypophosphatemia and osteomalacia. A PET/CT then showed a mass with low FDG uptake in the anterior compartment of the thigh (Fig. 7), which was then biopsied. The common tumors that produce FGF are hemangiopericytoma, hemangioma, giant cell tumor and non-ossifying fibroma.

Contrast enhanced CT scan shows a hypervascular lesion (arrow) in the anterior compartment of right thigh, with mild FDG uptake (arrow) on the PET study.

Fig. 7: Contrast enhanced CT scan shows a hypervascular lesion (arrow) in the anterior compartment of right thigh, with mild FDG uptake (arrow) on the PET study.

She was operated and the tumor removed. Most patients show dramatic recovery of their phosphorus levels, but the skeletal changes and fractures take time to heal. The patient is slowly getting better symptomatically.

The most common reason for delayed diagnosis (in her case 5 years with an average time of 4.7 years from start of symptoms to final diagnosis) is due to lack of awareness and the inability to find the tumor.

This case was recently presented by our DNB resident Dr. Parang Sanghavi in the Teaching Files Case Presentation meeting in Mumbai, where it won the first prize in the 3rd year residents’ category.

Tea and Fluorosis

Tea and Fluorosis

Who would have thought that drinking tea can produced fluorosis. In keeping with the theme of this blog, this short story / report about a patient who developed fluorosis after drinking copious amounts of tea (yes, tea), everyday is extremely interesting.

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