Monolateral Approach Research Articles

Microendoscopic Tailored Spine Decompression as a Less-Invasive, Stability-Preserving Surgical Option to Instrumented Correction in Complex Spine Deformities: A Preliminary Multicenter Experience

Study designA series of 32 patients, submitted to a tailored stability-preserving micro-endoscopic decompression for lumbar spine degenerative disease was retrospectively analyzed. ObjectivesThe aim of this study is to explore the effectiveness of a less invasive posterior spine decompression in complex deformities. We studied the potential advantages of the micro-endoscopic approach, supplemented by the piezoelectric technique, to decompress both sides of the vertebral canal, from a one side approach to preserve spine stability, ensuring an adequate neural decompression. MethodsThe patients were submitted to a selective bilateral decompression, using a monolateral approach, without the skeletonization of the opposite side. For the omo- and the contralateral decompression, we used a microscopic endoscopy-assisted approach, with the assistance of Piezosurgery, for a safe work near the exposed dura mater. Piezoelectric osteotomy is extremely effective in bone removal while safe on soft tissues. ResultsIn all patients an adequate decompression was achieved with a high rate of spine stability preservation. The approach was essential in minimizing the opening, so reducing the risk of spine instability. Piezoelectric osteotomy was useful to safely perform the undercutting of the base of the spinous process, for a better contralateral vision and decompression without damaging the exposed dura. In all patients a various degree of neurological improvement was observed, with no immediate spine decompensation. ConclusionsIn selected cases, the tailored micro-endoscopic monolateral approach for bilateral spine decompression, with piezosurgery assistance, is adequate and safe and showed excellent results in terms of spine decompression and stability preservation.

Minimally invasive microsurgical decompression of the lumbar spine using a novel robotised digital microscope: A preliminary experience.

The operative microscope (OM) represents, to date, the standard for neurosurgical procedures. However, new technologies have been proposed during the latest years to overcome its limitations, from high-quality exoscopes to complex robotised visualisation systems. We report our preliminary experience with a novel digital robotised microscope, the BHS RoboticScope (RS), for minimally invasive spinal surgery. We employed the RS in five consecutive patients who underwent bilateral lumbar spine decompression through a monolateral approach. Patient outcomes, device technical characteristics and the surgeon's personal perspectives have been evaluated. No complications occurred. All procedures were concluded without switching to the microscope. Image quality, lightning, depth perception and freedom of movement were judged satisfactory as compared to the standard microscope. The easy maneuverability and the high quality of pictures provided by the RS device improve the surgeon's comfort in deep fields, representing an effective option for minimally invasive spinal procedures.

Clinical and radiological outcomes following open door laminoplasty: a single center evolution of the technique.

The aim of the present study was to compare and describe clinical and radiological outcomes after two different variants of open door laminoplasty for cervical spondylotic myelopathy (CSM). Fifty-five patients underwent cervical laminoplasty for CSM. Between 2005 to 2009, 32 patients underwent open-door laminoplasty (Group A) performed with a monolateral exposure with contralateral "green stick" laminar fracture. A technical variant consisting in bilateral exposure, spinous process removal and symmetrical muscular closure was applied in the other 23 (Group B), from 2009 to 2016. A retrospective analysis of surgical results between the two groups was performed. In group B, the mean operative time was longer, and the mean volume of intraoperative blood loss was much higher than in group A. Both differences were not significant (P=0.1601 and P=0.0884, respectively). The average hospitalization was non-significantly longer in group B (7.3±1.8 vs. 6.5±1.6 d; P=0.0947). Postoperatively, axial neck pain was more severe in group A at last follow-up than preoperatively (P>0.05). mJOA scores and Nurick grades improved significantly in both groups at last follow-up; in group A, the mean recovery rates were 41.5% by mJOA scores and 29.4% by Nurick grades, whereas in group B they were 52.7% and 36.8%, respectively. Applying some few variations to a standard monolateral approach, although slightly more time and blood consuming, could reduce the incidence of long-term axial symptoms and, in our experience, are not burdened by worsening of outcomes. A prospective, multicentric study with a longer follow-up should be conducted in order to confirm our findings.

Looking at the Future of Motion Preservation Surgery in the Lumbar Spine with the Experience of the Past

Introduction In the 1970's, Kirkaldy-Willis first described the “Degenerative Cascade” of DDD. Observation of demographic studies shows more back pain in younger adults (30 to 50 years) than in elderly adults (over 60 years) in which osteoarthritis problems are prevalent to disc problems. The aim of this study is to demonstrate if and when an interlaminar elastic motion preservation device for disc assistance can stop or reverse the degenerative cascade of the lumbar spine in younger adults. We used in this study a new motion preservation device not interspinous but interlaminar. The IntraSpine® device (Cousin Biotech, France), is manufactured in medical silicon 65 shore coated by an adherent pure polyester terephtalate sleeve and the frontal extremity is further covered by a silicone film that prevents adhesion to the neural structures in cases of surgical bone or soft tissue removal. Material and Methods Group 1: 60 patients (mean age 34.5 years, 38 female an 22 male) affected from back pain from a minimum time of two years and after the failure of conservative treatment for at least 6 months, received a minimally invasive surgical procedure implanting this IntraSPINE® device at one or two levels. Group 2: 54 patients (mean age 32,6 years, 24 male and 16 female) affected from big extruded disc hernia received the some implant after the removal of the hernia in the some surgical procedure at one level, to prevent the subsequent chronic LBP due to a rapid collapse of the disc height. From the literature we know that in this young group of patients the percentage of the chronic LBP in the late follow up (5 years) it's ~70%. The results with a minimum follow-up of 4 years were evaluated from the clinical point of view regarding the LBP with VAS and ODI tests. All patients were also subjected to an MRI control. The surgical procedure was performed by monolateral approach and in many cases in local anesthesia in group 1 and in general anesthesia and equally by monolateral approach in group 2. The source of the pain in this group of patients (facet joint pain) was demonstrated by a positive response to the facet joint block test (The response was considered positive for a transient reduction of pain at least of 70%). Prior to surgical procedure, all patients underwent an MRI, a CT Scan and a dynamic X-ray of the lumbar spine. The stage of the degenerative cascade was between grade III and IV according to Pfirrmann. Results Group 1:in ~20% also in presence of good clinical results we highlighted a moderate progression of the cascade, in about the 50% the Pfirrmann grade was unchanged, but in ~30% we highlighted a partial rehydration of the disc which means a initial reversion of the degenerative cascade (patients with the lower grades of degeneration). Group 2: the percentage of a very uncomfortable LBP in this group was 24%, and the number of the recurrences was 2 (5%) and in only 1 case we performed a new surgical procedure. The maximum amount of blood lost in both group was 80 cc and the mean time of the surgical procedure was 28 minutes (from 18 to 37) in the group 1 and 41 minutes (from 34 to 46) in the group 2. Conclusion The close observation of the right indications and the proper selection of patients is strictly recommended. The mininvasive and relatively easy surgical procedure do not induce the surgeons of an indiscriminate use of this device. The wrong level implant is the mast frequent mistake. From the observation of these very important points we believe that are obtained this very good results even should be necessary a big number of case study, a longer follow up and a randomized multicenter study. The absence of major complications, the minimally invasive surgical procedure and the good clinical results allow us to say that with a correct patient selection we can prevent that this disease from acute becomes chronic, and thus its natural progression. Last but not least if we performed this surgical procedure in the earliest stages of the degenerative cascade, we can reverse its trend.

Reply to the letter “Renal denervation: The potential causes of non-response”

I thank Dr Liu for his letter [1] and appreciate the interest he demonstrates on the case report on the effects of monolateral renal denervation on sympathetic nerve traffic, clinic and 24-hour ambulatory blood pressure in a patient with true resistant hypertension [2]. The letter by Dr Liu poses a number of questions and it allows one to provide additional information on the case report that space constraints prevented to add in the original paper. As recommended by current European Guidelines on hypertension as well as by the most recent international Expert Consensus Statement on renal denervation [3,4], our patient before undergoing the renal denervation procedure was carefully screened for ruling out any secondary nature of his high blood pressure state. All the instrumental and laboratory tests performed excluded a hypertensive state of secondary nature. Similarly, as already mentioned in the case report publication [2], adherence to treatment was also accurately checked before the procedure, in order to rule out the possibility that a poor patient's adherence to drug treatment was responsible for the clinical state. Adherence to treatment was also carefully checked during the follow-up after the procedure. These evaluations allowed one to exclude any change in the dosage and/or number and type of antihypertensive drugs taken by the patient. Finally, we would like to emphasize that at present the number of ablation points is not a strictly fixed variable (although 6 is recommended as routine procedure), and that this number depends on many variables, including the length of the renal artery as a main factor. I would like, however, to emphasize that, as stated in our case report, the reason of failure of the ablation in one renal artery was the damage of the guide catheter and not the vascular injury. In summary, mentioning again the recommendations of the European Guidelines document [3] and the latest Expert Consensus Statement [4], which I have contributed to in writing, I would like to emphasize that bilateral renal denervation is the goal standard to try to obtain a blood pressure reduction in true resistant hypertension, the monolateral approach not guaranteeing a sympathetic deactivation and thus a blood pressure reduction.

Positioning of the ablation catheter in total endoscopic ablation

Minimally invasive ablation of atrial fibrillation is an option in patients not suitable for or refractory to catheter ablation. Total endoscopic ablation can be performed via a monolateral approach, whereby a left atrial box lesion is created. If the ablation is introduced from the right side, the positioning of the ablation catheter on the partly hidden left pulmonary veins is of vital importance. Using thoracoscopy in combination with multiplane transoesophageal echocardiography, the anatomical position of the ablation catheter can be established. Our experience in over 60 procedures has confirmed this to be a safe technique of total endoscopic ablation.

Durable staged hybrid ablation with thoracoscopic and percutaneous approach for treatment of long-standing atrial fibrillation: A 30-month assessment with continuous monitoring

Electrophysiologic and surgical procedures to treat stand-alone atrial fibrillation (AF) have recently evolved, but disappointing results in patients with long-standing persistent (LSP) AF have challenged the durability of these procedures. Lone AF patients (n=36) with either LSP-AF (n=28) or persistent AF (n=8) were prospectively enrolled in the study and consecutively treated by thoracoscopic ablation followed by electrophysiologic evaluation 30 days afterward. Mean left atrial dimension was 50.3±5.5 mm, and average AF duration was 72.8 months (range, 7-240 months). The thoracoscopic procedure was a right monolateral approach to create a box lesion using a temperature-controlled radiofrequency device with suction adherence. A continuous rhythm monitoring device was implanted at the end of the operation. Thoracoscopic ablation was successfully completed without morbidity or mortality and without any intensive care unit stay. Intraoperative exit and entrance block was achieved in 100% and 88.8% (32/36) of patients, respectively. At 33±2 days after the operation, an electrophysiologic study confirmed entry-exit block in 83.3% (30/36) whereas pulmonary vein reconnections were observed in 16.7% (6/36) of patients. Additional transcatheter lesions were performed in 61.1% (22/36) of patients. At a mean follow-up of 30 months (range, 1-58 months), 91.6% (33/36) of patients are in sinus rhythm with 77.7% (28/36) of these patients off antiarrhythmic drugs and 88.8% (32/36) free of warfarin. Long-term incidence of left atrial flutter was 0%. The combination of a surgical box lesion and transcatheter ablation in a hybrid approach provided excellent durable clinical outcomes in patients with LSP-AF.

Left atrial ablation through monolateral thoracotomy

We read with interest the recent paper of Solinas et al. [1], who first described a technique to perform a left atrial (LA) ablation with bipolar irrigated radiofrequency (RF) through a single right thoracotomy. This work confirms the feasibility of pulmonary veins isolation (PVI) through the monolateral approach and therefore sustains the use of minimally invasive surgery (MIS) for the treatment of atrial fibrillation (AF). However, two questions about the treatment of AF are currently unanswered: What is the best approach? What is the best lesion set? Wolf et al. [2], using a bipolar RF device, support a full left maze with testing of the electrical block. Unfortunately, this techniqueneeds a bilateral approach, increasing invasiveness. Some authors [3,4] also described AF ablations through a monolateral approach. However, this procedure was performed ‘on pump’ and on cardioplegic arrest. From these articles, we could conclude that best approach and best lesion set are inversely related.Fromthis point of view, Solinas et al., using abipolarRFdevice, didnotchange this paradigm. In fact, their technique was only in part performed on beating heart but, itwas alwaysduring theextracorporeal circulationand for a concomitant mitral valve disease, where left atrium was opened. Solinas et al. [1] have not explained the selection criteria of patients. According to the literature, persistent and permanent AF could have a more extended lesion set. In our opinion, this treatmentmay count almost themitral isthmus to avoid supra ventricular tachycardia, like atypical flutters. Ideally, surgeons would like to develop a technique easy to perform, monolateral, off-pump, epicardial, with adequate transmural lesion set, and good clinical outcomes. Bipolar RF clamp devices that appear to be most capable of reliably producing transmural lesions are least able to be minimally invasive. Alternative sources of energy could be taken into account to solve this dilemma. Recently, we described a method for AF ablation using high-intensity focused ultrasound (HIFU) energy [5] with promising results. However, it is our opinion that a good selection of the patients should be always taken into account. In fact, even if we performed AF ablation with an HIFU device, we were not able to create a bi-atrial lesion set useful for patients with more severe and advanced states of AF. In conclusion, Solinas et al. plead a case of AF treatment moving toward a simpler and less-invasive procedure. We hope industries will respond by applying the innovative technology to the needs of new instruments capable of retaining the efficacy of the full Cox-maze procedure and really adapted for MIS. References

Innovative Monolateral Approach for Closed-Chest Atrial Fibrillation Surgery

Surgical treatment of atrial fibrillation recently gained new popularity since the introduction of different energy sources as an alternative to the original cut-and-sew technique. Recently an innovative approach for closed-chest thoracoscopic epicardial pulmonary veins isolation has been described for patients suffering from lone atrial fibrillation. Nevertheless in an effort to further reduce the invasiveness of closed-chest atrial fibrillation surgery, we developed a novel monolateral approach for thoracoscopic arrhythmia surgery.