Celia SampolSep 21

This patient can now hold his hand steady (Ohio State Univ. Wexner Medical Center)

A new minimally invasive approach to treat essential tremor through ultrasound waves sent to the brain was approved last July by the FDA. This innovative system has the advantage of avoiding the risks of a brain surgery. But it has an ethical downside: It burns part of the brain cells. And there are no studies yet about the long-term effects.

Kristin “Sunny” Berry first noticed the tremor in her hands at school when she was 7 years old. It has gotten worse through the years, affecting her head and making it difficult to even eat, get dressed, or write. “Brushing my teeth was just a nightmare; I could write but nobody could read it,” she told to MedicalExpo e-mag during a phone interview.

She started looking on the Internet and found out about the HIFU procedure—High Intensity Focused Ultrasound treatment—performed by a couple of centers in the world, including Ohio State University Wexner Medical Center. She decided to apply. It was like a dream come true for Kristin. In mid-April, after a four-hour-session, she came back home without almost no shaking in her hands or head. “I could feel the difference right away—it was amazing,” she said.

Effects Are Immediate

The system is pretty simple. The patient puts on a helmet at the beginning of the procedure. This helmet has over a thousand ultrasound probes that will deliver the energy inside the brain. Then the person lies down on a MRI table so doctors can obtain images of the brain. When they get these pictures, they locate the area called the thalamus. It is a central structure of the brain that possesses over 120 components. One of these components is involved in generating the tremors.

Once doctors have identified this area, they apply ultrasound waves that traverse the skull and converge to the targeted area where they generate energy—about 1,000 watts that slowly heat up that part of the brain. By heating it up, the system burns away certain brain cells that are causing the tremor. The company InSightec manufactures the ExAblate Neuro, the focused ultrasound device approved by the FDA.

“The patient receives no anesthesia—they are awake the whole time and interacting with us,” explained Dr. Ali Rezai, director of the Center for Neuromodulation at Ohio State’s Neurological Institute. “We do tests first. So we deliver small amounts of the energy to see if there’s any benefits or any side effects. If the patient doesn’t report any problem after 10 or 15 minutes, then we increase the energy.” The patient sees the changes directly on the MRI table.

Not a First- or Even Second-Line Therapy

“This new technique is advantageous because it is basically performing a brain surgery without cutting the skin or opening the bone. It’s minimally invasive,” said Dr. Rezai. Still, one major issue remains: The ultrasound waves are actually burning a part of the brain, and the cells that are burnt won’t regenerate.

Before and after writing examples (Courtesy of Ohio State University Wexner Medical Center)

Dr. Rezai acknowledges that it is an important point. “That’s why we don’t do this approach as a first-line therapy or even second-line. We are talking about patients who have tried various medications and other treatments, and despite the best attempts for years their tremor has become so severe that they have difficulty with basic activities like eating, dressing themselves, writing, working. So it comes to a point where they become very disabled.”

According to him, burning the brain or the nerves is commonly used worldwide for example to treat chronic pain. Kristin, for her part, “tried not to think too much about that.” “It was worth it and I would do it again” if needed.

Plans to Treat Depression or Compulsive Disorder

Rezai acknowledged, “Yes, if you don’t target exactly in the precise area, it’s possible that the patient may have problems in terms of sensation loss, or difficulty speaking or moving, but it’s extremely rare. The safety profile is very strong with this,” he added.

A randomized trial was published in The New England Journal of Medicine on August 25. In this study involving 76 patients with medication-refractory essential tremor, transcranial-focused ultrasound thalamotomy significantly reduced hand tremor at three months, and the effect persisted during the 12-month study period. Side effects included sensory and gait disturbances. But there are no studies yet to tell what could be the effects over two, three, or five years.

“I don’t think there could be a side effect because if there was a big problem you would see it right away on the patient, but the issue could be the tremor coming back,” said Dr. Rezai. According to him, this approach is CE-certified for Parkinson’s disease. Researchers are now looking into ways to use it to treat epilepsy, depression or even obsessive-compulsive disorder.

Howard WolinskySep 21

Retort 1850 (Painting of William Jensen - Oesper Collections, University of Cincinnati)

Behold the humble test tube. If you think it’s the symbol of chemistry, you’d be wrong, argues William Jensen, a chemistry historian and professor emeritus at the University of Cincinnati Department of Chemistry.

“At best, it’s a co-symbol,” said Jensen, who has combed paintings and old chemistry texts in search of data to date the test tube and other apparatus used in chemistry labs.

If you think the test tube dates back to alchemy, wrong again, said Jensen, who has been able to trace the test tube back only to the first decade of the 19th century. Actually, you’d probably be thinking of spherical vessels with a long downward-pointing neck known as the retort, glass or copper vessels used in distillation. (The idiom “snappish retort” may refer to the vessel.)

Liquids are placed in the retort to be heated. The neck acts as a condenser, allowing the vapors to condense, flow along the neck and be collected underneath, according to Wikipedia. In the case of alchemy, you would actually be thinking instead of a retort. No self-respecting alchemist would’ve been without one.

Jensen said, “Virtually every modern-day artistic depiction of an alchemist will feature a retort as the centerpiece of the alchemist’s laboratory,” he said. “Perhaps no single piece of laboratory apparatus is more intimately associated in popular culture with the practice of chemistry than is the retort.”

A Snappy Retort

1494 (Painting of chemist William Jensen – Oesper Collections, University of Cincinnati)

A retort is depicted on the Boy Scouts of America’s chemistry merit badge, said Jensen. Likewise, the insignia for the Chemical Corps of the United States Army incorporates retorts.

Retorts first appeared in the literature dealing with distillation sometime in the 14th or 15th century, he said in an article entitled “A Snappy Retort” in Notes from the Oesper Collections (Museum Notes, January/February 2013, 1-6).

Common laboratory apparatus, including flasks (think Walter White, the high school chemistry teacher turned meth kingpin), beaker (think the Muppets) and retorts (think Merlin) before the 19th century was flawed. 

Jensen said that’s because it did not have a high melting point; was not resistant to being destroyed by water, alkalis and acids; was not colorless and transparent; and was not resistant to thermal and mechanical stress.

Jensen has traced the creation of the test tube to the beginning of the 19th century. He said test tubes were used to heat chemicals, which, based on the colors that were seen, allowed chemists to identify chemicals.

Here Comes the Pyrex

Throughout the century, innovations in glassmaking, such as making it thin with tough glass, made the modern test tube possible.

Test tube rack from 1880s (Courtesy of Oesper Collections, University of Cincinnati)

In 1915, Corning Glass introduced Pyrex, which was superior in withstanding mechanical shock, Jensen wrote in his Ask the Historian column entitled “The Origin of Pyrex” (J. Chem. Educ., 2006, 83, 692-693). Pyrex first was used in cookware, but soon was applied to lab glassware. Test tubes are hanging in there. Retorts have been in decline for more than a century.

“Ironically, despite its continued use as a symbol for the practice of chemistry, the retort had already begun to disappear from day-to-day laboratory practice by the early decades of the 20th century…”, he said.

Celia SampolSep 21

The SOMATOM Force (Courtesy of Siemens Healthineers)

At the Congress for the European Society of Cardiology (ESC) from August 27-31 in Rome, Siemens Healthineers presented what it calls its new “workflow approach” for complex, minimally invasive procedures. The goal is to help cardiologists optimize medical imaging at every stage of cardiology treatment, from diagnosis to follow-up care.

Imagine a patient with a heart valve problem—not an emergency situation, but a complex, ongoing case, with the quality of the patient’s life going down significantly. First of all, an exact patient assessment is crucial to decide for the optimal treatment. Based on this information, an interdisciplinary heart team decides whether surgical or minimally invasive intervention is the most appropriate treatment approach.

In those cases, a minimally invasive procedure is the best choice to treat structural heart diseases. With minimally invasive procedures, open thorax surgery is not needed. The patient would probably avoid general anesthesia which translates into shortened recovery time and therefore less time to be spent at the hospital.

The ACUSON SC2000 (Courtesy of Siemens Healthineers)

“Minimally invasive procedures are an alternative for some patients, but the physicians face also some challenges,” explained Doris Pommi, head of marketing in cardiology at Siemens Healthineers, during a phone interview with MedicalExpo e-mag. “Physicians treat the patient by inserting a catheter via a femoral or apical access for heart valve treatment. Therefore, the physicians don’t see the [heart] valve physically, like in an open surgery, so the need of excellent image quality, information about anatomy and physiology, and guidance during the procedure is crucial,” she added.

Devices become smaller and the material they’re made of could be difficult to visualize.  For an optimal outcome, it is necessary to assess the correct placement, deployment and function of the device. That’s where Siemens Healthineers comes into the game. The German company offers to “provide the imaging modalities and tools to support the assessment of the patient before the procedure”, to “guide the exact placement during the procedure” and finally to provide imaging and tools to support after the procedure if everything is working well.

Therapy: Checking the Placement of the Implant Immediately

These are two examples for the diagnosis and assessment step:

The ACUSOM SC2000 Prime combines two technologies: the ultrasound system that can produce 3-D transesophageal echocardiography full-volume color Doppler images of the heart and blood flow, and the integrated eSie Valves analysis software that supports precise measurements of the individual heart valves in just seconds.

Dual-source CT scanners from Siemens Healthineers make it possible to perform CT imaging with low doses of radiation. The high rotational speed of the SOMATOM Force and the resulting temporal resolution, make it unnecessary for patients to hold their breath during the scan or to take medications to regulate their heartbeat, explained Siemens Healthineers in a press release.

The SOMATOM Force (Courtesy of Siemens Healthineers)

Finally, the real-time 3-D ultrasound imaging provided by the ACUSON SC2000 Prime comes into play with minimally invasive mitral valve therapy, since its full-volume color Doppler function enables the assessment of the implant immediately, while the patient is still on the operating table. The heart team sees immediately, if the treatment was successful.

The whole clinical pathway needs “very good teamwork,” said Pommi.