Simplicity (2018)

OR: operating room PDA: patent ductus arteriosus My aim in this talk is to try to break down and unscramble some of the sophisticated problems we face in our field and demonstrate the power of simplicity in neurological surgery. Let me share a story with you that demonstrates the importance of simplicity in surgery. This is Lorraine Sweeney in 1938, a 7-yr-old girl from Brighton, Massachusetts who fell ill with respiratory distress, failure to thrive, and a heart murmur. This is Robert Edward Gross, the man who saved her life. He was born in Baltimore on July 2, 1905. A congenital cataract rendered him blind in 1 eye, so his father, a piano maker, had him take apart and rebuild intricate clocks to help him learn depth perception so he could join the family business. But he received a gift of Cushing's biography of Osler and was inspired to become a doctor. As a medical student at Harvard, Gross sat in the amphitheater to watch his hero Cushing operate. But Cushing looked up at Gross, asked him to identify himself, and when Gross said he was a medical student, Cushing threw him out of the operating room (OR) and told him to return when he was a real doctor—a humiliating experience that Gross never forgot. Gross went on to achieve international recognition as chief resident in surgery at Boston Children's Hospital when he diagnosed Lorraine Sweeney with a patent ductus arteriosus (PDA), a small communication between the pulmonary artery and aorta that had failed to close after birth. No one had ever undergone successful repair of a PDA and indeed, no one had undergone successful congenital heart surgery. But Gross had figured out a way to fix the problem and he asked permission to do the procedure from his boss, William Ladd, the Surgeon-in-Chief. Ladd, an imposing man, forbade Gross to do the procedure, believing it to be far too risky. So Gross waited until Ladd was on vacation on a boat to Europe, and on August 26, 1938, he operated on Lorraine and successfully ligated the ductus with a single silk suture. Ladd learned what Gross had done by reading the newspaper and promptly fired Gross when he returned from vacation. But others noted that Gross had done something remarkable—the first successful congenital heart surgery in the world, and Ladd was forced to rehire Gross. Gross went on to succeed Ladd as Surgeon-in-Chief and became the first Ladd Professor at Harvard Medical School. Sweeney survived and visited her surgeon in 1963 on the 25th anniversary of her operation. She is still alive today, a great-grandmother in her 80s. But the reason I remember Gross is his devotion to the power of simplicity, with his comment, still emblazoned on the wall of his Operating Room at Boston Children's Hospital, “If an operation is difficult, you are not doing it properly.” I recently did a book: “Pediatric Neurosurgery: Tricks of the Trade”, which begins with those words from Gross (Figure 1). The book describes technical nuances about how to operate smoothly and stay out of trouble. In neurosurgery we do many complicated procedures, and I’ll describe one of them to you now, to emphasize that even complex procedures are simply a summation of a series of basic steps, and it is attention to these basic steps that determines the success of the operation.FIGURE 1: Tricks of the Trade. Reprinted with permission of Thieme from Cohen AR. Pediatric Neurosurgery: Tricks of the Trade. 2015.Recall the words of Leonardo da Vinci, “Simplicity is the ultimate sophistication.” Here is one of the more complex operations we do, the infratentorial supracerebellar approach to pineal region tumors, first performed successfully by Fedor Krause of Berlin in 1913, with the patient in the sitting position and an assistant holding the head (Figure 2).FIGURE 2: Fedor Krause. CC BY-4.0, Wellcome Images, M0010972.In 1932, 7 yr before his death, Cushing noted, “Personally I have never succeeded in exposing a pineal tumor sufficiently well enough to justify an attempt to remove it.” In his series of 14 pineal tumors, the case mortality was 100%. Technical advances have enabled us to approach this region with greater safety. But it is still the meticulous attention to every step of the procedure that really determines its success. Here's a child with a symptomatic pineal region tumor (Figure 3). We used an infratentorial supracerebellar approach with the patient in the sitting position, with attendant monitoring lines. The craniotomy is fashioned with its rostral end just inferior to the transverse sinuses. The rostral bone can be beveled with a drill to provide extra exposure on top, where every millimeter helps. The dura is opened in a V shape, with oblique lateral incisions to provide optimal access to the supracerebellar corridor (Figure 4). Alexander Pope said “There is a certain majesty in simplicity.” Using gravity as a retractor opens a beautiful passage to the pineal gland at center of the brain, the site that Descartes called the seat of the soul.FIGURE 3: Pineal region tumor.FIGURE 4: A, Posterior fossa bone flap. B, Dural exposure. C, Dural opening.The pineal arachnoid is thick, and the midline precentral cerebellar vein can be divided without problem. Working underneath the vein of Galen, the tumor is resected, providing a panoramic view of the third ventricle. A watertight dural closure is achieved using a graft and the bone flap is replaced (Figure 5). A gross total resection can be accomplished without violating the brain (Figure 6). The elegance of complex neurosurgical procedures comes from the adoption of a successive series of basic technical maneuvers.FIGURE 5: A, Thickened arachnoid. B, View into third ventricle tumor. C, Watertight dural closure with graft.FIGURE 6: A, Preoperative contrast-enhanced T1 MRI. B, Postoperative contrast MRI-tumor resected.Hans Hoffman, the abstract expressionist painter said, “The ability to simplify means to eliminate the unnecessary so the necessary may speak.” These days we hear a lot about overlapping surgery and the requirement for the surgeon to be present for the critical part of the case. In my opinion, the critical part of the case begins well before the patient enters the OR, and that's when surgical judgment begins. According to an old Hebrew proverb, the art of surgery is the ability to use superior judgment to avoid having to use superior skills. The goal of the surgical team in every case is to get the patient safely and expeditiously through the procedure and out of the OR. A time out is performed, checklists are run through, and everyone in the room stands on equal footing. The patient is the center of all activity. The importance of positioning cannot be overstated. Placing the head in a dependent position can lead to increased venous pressure and bleeding, as can twisting of the neck, by causing jugular vein compression. The region of interest is generally placed at the highest point in the field. For midline posterior fossa approaches a military tuck position provides optimal exposure of the foramen magnum (Figure 7).FIGURE 7: Military tuck position.The scalp is richly vascular and blood loss is minimized by infiltration with epinephrine and applying pressure on either side of the incision (Figure 8). Scalp clips can be used. The scalp can be mobilized in the avascular suprapericranial plane, and the pericranium can be harvested as a separate vascularized flap based on the supraorbital arteries. This is helpful, for example, if the frontal sinus is entered and needs to be excluded from the intracranial compartment (Figure 9).FIGURE 8: Application of pressure during scalp incision. Reprinted with permission of Thieme from Cohen AR. Pediatric Neurosurgery: Tricks of the Trade. 2015.FIGURE 9: A, Bifrontal incision. B, Elevation of vascularized pericranial flap. Reprinted with permission of Thieme from Cohen AR. Pediatric Neurosurgery: Tricks of the Trade. 2015.The good surgeon will always have an instrument in each hand and rarely takes his or her eyes off the operative field, holding up a hand when requesting an instrument, without looking away. The surgeon is always thinking 2 or 3 steps ahead. The finest surgeons practice economy of movement, with 1 action blending into the next. Nothing appears hurried. Every action has a purpose and there are no unnecessary maneuvers. The craniotomy is fashioned by making burr holes, here with a power perforator. The perforator has a clutch that stops the drill from spinning once the inner table of the skull is traversed, but this safety measure is not guaranteed, so the wise surgeon uses the nondominant hand as a brace to prevent plunging. The burr holes are then connected using a high speed drill and footplate. Cuts are directed away from venous sinuses, and the most dangerous cuts, those for example, over the sagittal sinus, are made last so that if significant bleeding occurs the bone flap can be elevated expeditiously (Figure 10).FIGURE 10: A, Burr hole fashioned with power perforator. B, Elevation of bone flap. Reprinted with permission of Thieme from Cohen AR. Pediatric Neurosurgery: Tricks of the Trade. 2015.The dura is opened with a #15 blade knife on a long handle and the dural opening is extended using Metzenbaum scissors. If the brain is tight the scissors are angled obliquely so that the internal blade does not injure the underlying brain (Figure 11). Exposure is everything. If automatic retractors are used they should be low in profile, so the operator's hands are as close to the wound as possible.FIGURE 11: Beveling the Metzenbaum scissors. Reprinted with permission of Thieme from Cohen AR. Pediatric Neurosurgery: Tricks of the Trade. 2015.Whenever possible, the tumor should be devascularized early. Prompt access to feeding vessels is advantageous, such as the anterior choroidal artery supply for a choroid plexus papilloma. Deep feeders, such as the posterior choroidal vessels, can sometimes be embolized preoperatively. A layered closure is performed, using a dural graft if necessary. The bone is replaced and the galea and scalp are reapproximated in a tension-free fashion. Here are 2 workhorse craniotomies demonstrating the stepwise contribution of basic surgical technique. The pterional craniotomy begins with a curvilinear incision in front of the tragus coursing just behind the hairline. A myocutaneous flap is reflected. The dura is opened and covered with moist collagen. The Sylvian fissure is split and cerebrospinal fluid is drained to relax the brain. Here the optic nerve can be seen through the arachnoid at the depths of the field. Further dissection exposes the optic chiasm and right internal carotid artery (Figure 12). Higher magnification discloses a mass between the right optic nerve and carotid artery. This was an 18-mo-old girl with precocious puberty from a hypothalamic hamartoma.FIGURE 12: A, Right pterional craniotomy. B, Right optic nerve and carotid artery. C, After resection of hypothalamic hamartoma.Here the mass has been removed. And the pathological specimen was a hypothalamic hamartoma, whose removal cured the youngster's precocious puberty (Figure 13).FIGURE 13: Hypothalamic hamartoma resected.The dura is closed. The bone flap is replaced, here with absorbable plates and screws, as the child was so young. The interhemispheric anterior transcallosal approach provides exposure to the lateral and third ventricles without the need for a cortical incision. Here is an illustration of a colloid cyst of the third ventricle by Dorcas Hager Padget, Walter Dandy's artist (Figure 14). Dandy was the first to perform the transcallosal approach in 1921 on this 24-yr-old woman with headaches and papilledema. He used a posterior interhemispheric transcallosal approach, sectioning 1 fornix to remove the tumor, a colloid cyst. The patient had a stormy course but survived the procedure.FIGURE 14: Colloid cyst of the third ventricle. From Dandy WE: Benign Tumors in the Third Ventricle of the Brain: Diagnosis and Treatment, Fig 12, page 15. Charles C. Thomas, Springfield, Illinois, 1933. Public Domain.The modern approach uses an anterior transcallosal corridor. I prefer a bicoronal scalp incision. The scalp is reflected in the suprapericranial plane. A frontal bone flap is elevated with its medial extent on the midline. In this case, because the patient was an infant, the bone was removed with scissors. The dura is opened and reflected medially toward the sagittal sinus (Figure 15).FIGURE 15: A, Bicoronal scalp incision. B, Right frontal craniotomy. C, Reflection of the dura medially.The right hemisphere is gently mobilized away from the falx until the glistening white corpus callosum is identified (Figure 16). Care is taken to avoid occluding the sagittal sinus. The corpus callosum is opened working between the pericallosal arteries, providing a clear view of the lateral ventricle and foramen of Monro. If you are lost, remember that the veins increase in caliber as they approach the foramen of Monro, and there is no choroid plexus anterior to the foramen.FIGURE 16: Corpus callosum.A good rule of thumb is that the foramen of Monro is situated about 2.5 cm posterior to the genu of the corpus callosum. To estimate the location of the foramen of Monro using external landmarks you can draw an imaginary line from the bregma to the external auditory meatus, which will bisect the foramen. As the great Bruce Lee once said “I fear not the man who has practiced 10,000 kicks once, but I fear the man who has practiced one kick 10,000 times.” This emphasizes the importance of deliberate practice. Careful attention to basic surgical technique will help the operator minimize complications. Even small mistakes can lead to big problems. Let me share 1 of my complications with you. An 8-yr-old girl came to the hospital with progressive headache, nausea, and vomiting over 3 wk. She had papilledema and truncal ataxia. Computed tomography showed a large fourth ventricular tumor with hydrocephalus, masses in the left lateral ventricle and diffuse subarachnoid seeding. She deteriorated in the Emergency Room and we operated urgently, placing an external ventricular drain followed by posterior fossa craniotomy and tumor resection. There was a tumor in the left frontal horn, so I placed the drain on that side endoscopically, allowing me to biopsy the tumor at the same time. Here is the left foramen of Monro, with tumor in the frontal horn. I introduced the biopsy forceps through a working channel in the scope. As I biopsied the mass it began to bleed profusely, and then the operative field turned completely red, obscured by blood. That's a pretty scary sight. A small artery had torn (Figure 17).FIGURE 17: A, Tumor seeding left lateral ventricle. B, Biopsy forceps. C, Bleeding from a torn vessel. D, Operative field obscured by blood.What do you do in a situation like that? The first thing I try to do is to blame 1 of the residents. That rarely helps. The next thing is to not panic and keep the endoscope focused in the exact same direction, even though the field is obscured. Irrigation with warmed Ringers solution will often clear the field. Sometimes a bleeding vessel comes into view and can be coagulated. In this case the bleeding stopped after 7 min of irrigation. We placed the drain, turned her over and took out the tumor, which was a medulloblastoma. We removed the drain after 4 d. She received craniospinal radiation and chemotherapy for 1 yr. And somehow, despite the fact that she had a disseminated medulloblastoma, 10 yr later she is currently a straight A senior in high school, with diminished hearing on 1 side and some truncal ataxia, but otherwise well. We dodged a bullet here. But the mistake I made was in the preoperative planning. I thought it would be clever to biopsy the lateral ventricular tumor while placing the drain. If I had it to do again I would not have done the endoscopic biopsy. It did not change my management of the case. William James said, “The art of being wise is knowing what to overlook.” These days we are so overloaded with data that it can be overwhelming. Much scientific writing is muddled and sometimes even incomprehensible. So my parting words—in science, and in life in general: keep it simple. And in surgery: “If an operation is difficult you are not doing it properly.” Disclosure The author has no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article.