Surgery



Innovating in the brain

 


“Shocked,” was what Laura Fernandez-Ortiz remembers feeling three years ago when an MRI revealed she had a tumour at the base of her skull. “And also very scared,” she adds. The 46-year-old paediatrician had been in excellent health, running a bustling private practice in Miami, Florida. Her doctors decided to keep an eye on the tumour, but last year, when a scan showed the mass had grown, they recommended she undergo surgery. Kate Ledger, Mayo Clinic, reports.

Like any concerned patient, Dr Fernandez- Ortiz went online to research surgical options for olfactory groove tumours, eventually making an appointment at a local medical centre for an open craniotomy to remove the growth. Her medical training gave her reservations about the invasiveness of the procedure. “I wasn’t happy about it. I knew it would involve retraction of the brain and possible cellular injury,” she says. “I scheduled it, but I continued making calls.”

By chance, days before her scheduled surgery, she stumbled across a video about Alfredo Quiñones-Hinojosa, M.D., and a patient of his with a skull-base tumour. Using a new technique that he pioneered, Dr Quiñones had removed the tumour through the patient’s eyelid. This was exactly the type of minimally-invasive approach that Dr Fernandez-Ortiz had hoped to find. That same day, she called Dr Quiñones at Mayo Clinic in Jacksonville, Florida, a five-hour drive from her home, to see if she would be a good candidate for the same surgery.

A specialist in primary and metastatic tumours of the brain and tumours of the pituitary and brain stem, Dr Quiñones has made it his mission to improve neurosurgical techniques and the methods of diagnosing and treating tumours. One surgeon who operates with him attests: “He’s constantly innovating.” The author of more than 100 book chapters, 6 books, 315 papers in medical journals, and other resources including the Video Atlas of Neurosurgery, he serves as the chair of neurologic surgery and the William J. and Charles H Mayo Professor at Mayo Clinic in Florida. Today, this warm and energetic clinician-scientist focuses on addressing the most difficult tumours in ways that best help patients. As he puts it: “My goal is giving people hope.”

Every brain is different
For more than a decade, Dr Quiñones has been keenly interested in advancing techniques that access tumours while sparing surrounding tissue. When it comes to removing eloquent tumours, those occurring in the speech and motor areas, he strives to keep critical regions of the brain intact. But the speech centres of the brain, and their sizes, differ between patients and even between single- and multi-language speakers. “Like every face, every brain is different,” he says.

Over the years, he has become a specialist in performing what’s known as an “awake craniotomy”. Working with a team that includes Mayo Clinic epileptologists, Dr Quiñones maps the brain during the operation, allowing the resection of a tumour and the removal of the widest possible margins around the mass, while preserving the functional cortical regions. During surgery, patients are positioned on their backs with their heads secure in stereotactic frames. Though under general anaesthesia at the beginning and end of surgery, they are sedated in a comfortable twilight state throughout the procedure, so that they can converse, answer questions, identify pictures, and respond to commands. He introduced the use of a camera in front of their faces so he can monitor facial changes as well.

The critical piece of equipment Dr Quiñones’ team developed and patented is a 5X5 cm plastic screen with a grid of tiny, flat electrodes that are placed directly against the brain. A stimulator delivers a gentle pulse to each region, interrupting the normal electrical activity of that area. If patients fail to recognize a simple picture, answer a question, or follow a command to move an arm or a leg, Dr Quiñones knows to leave that part of the brain intact. Importantly, the mapping also enables what’s known as a supramarginal resection, removing the maximum surrounding tissue to prevent tumour recurrence.

The awake craniotomy minimizes the use of anaesthesia, which may alter the immune system and increase recurrence of some cancers. The mapping also records electrical activity of the brain to prevent potentially devastating seizures during the craniotomy. Collecting data from his surgeries, Dr Quiñones has found the awake craniotomy, accompanied by motor and speech mapping, reduces a hospital stay from approximately 8 days to a mere 4 days. Overall, patients have higher scores on quality- and quantityof- life assessments than those who have gone through a standard craniotomy.

Minimally invasive brain surgery
He also has devoted attention to improving the latest minimally invasive surgeries. Entering the brain through the nose has become acknowledged in the U.S. as the best means to remove pituitary tumours. Many surgeons insert a speculum in the patient’s nose and employ a microscope as they access the tumour. Dr Quiñones has adapted the transsphenoidal procedure, using the endoscope, a camera slimmer than a pencil. “It’s much less invasive and allows you to look deeper and around the corners,” he says.

The biggest alteration, however, is that while most surgeons enter through both nostrils simultaneously, the endoscope enables Dr Quiñones to enter through just one. A resident manipulates the endoscope as Dr Quiñones operates surgical tools through the same corridor in the nose. “The nostril on the contralateral side remains completely intact,” Dr Quiñones says. Significantly, his technique (used for tumours existing exclusively in the interior skull base known as the sella) does not remove the turbinates, the tiny bones in the nose that provide resistance to the air and the sensation of airflow. Patients are spared the rare consequence of endonasal surgery known as “empty nose syndrome”. As he’s studied his outcomes, Dr Quiñones has found patients who undergo the endoscopic approach spend less time in the operating room and typically go home sooner than those who undergo traditional endonasal surgery. He’s now exploring data to determine whether the one- or two-nostril approach best maintains patients’ sense of smell and taste.

Through the eyelid
Another innovation Dr Quiñonesbrought to the operating room was an improvement to the minimally-invasive “keyhole” surgery, which introduces tiny cameras and microsurgical tools to the brain through an incision in the eyelid. Several years ago, he realized he could access the same supraorbital bone, and map a route to the tumour, entering through the eyelid. The approach is sometimes an alternative to endonasal surgery, as it was for one patient, a voice-over actor, who was concerned surgery through his nose would ruin his livelihood.

As it turned out, a CT scan suggested that Laura Fernandez-Ortiz was an excellent candidate for the removal of the skullbase tumour through her eyelid. “The question is the patient’s frontal sinus,” Dr Quiñones explains. “A large cavity can lead to infection, but I’ve found a small cavity to be safe.”

At Mayo Clinic he operates side by side with plastic surgeon Antonio Forte, M.D. The procedure combines tumour removal with the approach of an upper blepharoplasty, the cosmetic surgery for aging eyelids. The entry point is a hidden fold within the upper eyelid, that still enables Dr Quiñones to proceed to the tumour at the skull base. Using intraoperative scans and a neuronavigational system, similar to a GPS, he’s able to precisely assess anatomy and instrument placement. At the end of surgery, Dr Forte closes the site and the scar remains well hidden.

For Dr Fernandez-Ortiz, the surgery provided not only a less invasive alternative to a craniotomy, but an easier recovery. She was home within days and working fulltime at her clinic within six weeks. She’s also pleased – as Dr Quiñones had hoped – that the absence of a scar means she can live her life after brain surgery with a sense of normalcy. “People who didn’t know I had a tumour have no idea I’ve had surgery at all,” she says.


In the Operating Room and beyond

Dr Quiñones is eager to see improved diagnosis and treatment of tumours, and he believes those advances can happen right in the operating room. Currently, he’s part of a team investigating whether the technology of optical coherence tomography (OCT), used since the 1990s to image the retina, can be co-opted to recognize diseased cells in the brain. Early results of the team’s studies showed OCT can distinguish normal excised brain tissue from denser pathologies, like brain cancer. Used intra-operatively, the non-invasive imaging may soon be able to show neurosurgeons exactly which tissue needs to be removed so they can resect a wide margin without causing unnecessary damage to surrounding areas.

He’s also interested in how best to treat brain cancers, and his patients donate tumour tissue to make the studies possible. One approach he’s investigating in his basic science lab is the use of stem cells, known to have two remarkable capabilities. For one, stem cells can migrate to the site of a tumour. Additionally, they have the ability to differentiate into any type of cell. His lab is studying whether souped-up stem cells, carrying specific anti-tumour proteins, can deliver their cargo directly to a tumour. Moreover, those stem cells may be able to coax highly malignant cancer cells, like glioblastomas, to turn into less migratory, more treatable cell types, like astrocytomas. So far, the team found the cellular therapy halted tumours in mice, laying the groundwork for future studies at Mayo Clinic that will test the therapy in patients.


New guidelines for surgical ablation for patients with Atrial Fibrillation

While there is no cure for atrial fibrillation – an irregular heart rhythm that can cause an increased risk of stroke – many successful treatments are available, including surgical ablation. A growing population of patients means an increased demand for care. In an effort to provide practitioners with the most up-to-date information, the American Association for Thoracic Surgery (AATS) assembled an expert board to study the available literature and develop evidence-based guidelines and best practices on surgical ablation for the treatment of atrial fibrillation. Their consensus statement is published in The Journal of Thoracic and Cardiovascular Surgery, the official publication of the AATS.

AATS leadership convened a 10-member board comprised of leading experts in the field, including cardiac surgeons, biostatisticians, and a leading electrophysiologist, to make recommendations based on rigorous study of unbiased scientific data. The resulting document offers guidance about surgical ablation based on morbidity and stroke outcomes associated with the procedure, as well as information about the state of hybrid procedures, the optimal ablation tools available, and clinical training.

“These guidelines are extremely important for a few reasons,” said lead author Niv Ad, MD, Professor of Surgery, Division of Cardiothoracic Surgery, West Virginia University School of Medicine. “This consensus statement demonstrates the safety of the procedure and the clear association with reduced early death compared to patients who were left with atrial fibrillation. It also clearly states that there is a reduction in late stroke and better long term survival with improved quality of life.”

“Clinical practice regarding surgical ablation of atrial fibrillation varies widely. This consensus statement should guide surgeons to provide the best therapy for their patients who have atrial fibrillation,” added co-author Marc Gillinov, MD, Department of Thoracic and Cardiovascular Surgery, The Cleveland Clinic, Cleveland, OH.

The guidelines offer a robust look at many facets surrounding surgical ablation and begin with morbidity, stroke risk, and quality of life outcomes for atrial fibrillation patients. For example, investigators found that concomitant surgical ablation for atrial fibrillation improves 30-day operative mortality, so it is recommended to be performed when indicated.

The recommendations also note that ablation does not increase the risk of periprocedural morbidity or early stroke/transient ischemic attack (TIA) and that late stroke/TIA is decreased by surgical ablation in a follow up longer than one year. Other topics covered include indications for off pump hybrid procedures, the recommended surgical ablation devices that are associated with reliable transmural lesions, and the importance of standardized surgeon training and education.

By creating these guidelines, the board wanted to deliver a comprehensive consensus statement on ablation with the goal that clear guidelines would encourage more surgeons and referring cardiologists to understand the operation’s potential value to patients with atrial fibrillation and utilize it when appropriate. “The methodology used for the guidelines is also unique and provided the members of the committee with rigorous unbiased statistical data to support their recommendations,” said Dr Ad. “This type of scientific rigor is unique compared to other guidelines published on this topic.”

  • doi: 10.1016/j.jtcvs.2017.02.027
Date of upload: 11th May 2017

                                  
                                               Copyright © 2017 MiddleEastHealthMag.com. All Rights Reserved.