Accuracy of augmented reality-guided drainage versus stereotactic and conventional puncture in an intracerebral hemorrhage phantom model.

BACKGROUND: Minimally invasive intracranial drain placement is a common neurosurgical emergency procedure in patients with intracerebral hemorrhage (ICH). We aimed to retrospectively investigate the accuracy of conventional freehand (bedside) hemorrhage drain placement and to prospectively compare the accuracy of augmented/mixed reality-guided (AR) versus frame-based stereotaxy-guided (STX) and freehand drain placement in a phantom model. METHODS: A retrospective, single-center analysis evaluated the accuracy of drain placement in 73 consecutive ICH with a visual rating of postinterventional CT data. In a head phantom with a simulated deep ICH, five neurosurgeons performed four punctures for each technique: STX, AR, and the freehand technique. The Euclidean distance to the target point and the lateral deviation of the achieved trajectory from the planned trajectory at target point level were compared between the three methods. RESULTS: Analysis of the clinical cases revealed an optimal drainage position in only 46/73 (63%). Correction of the drain was necessary in 23/73 cases (32%). In the phantom study, accuracy of AR was significantly higher than the freehand method (P<0.001 for both Euclidean and lateral distances). The Euclidean distance using AR (median 3 mm) was close to that using STX (median 1.95 mm; P=0.023). CONCLUSIONS: We demonstrated that the accuracy of the freehand technique was low and that subsequent position correction was common. In a phantom model, AR drainage placement was significantly more precise than the freehand method. AR has great potential to increase precision of emergency intracranial punctures in a bedside setting.

Mitigation of Blood Load Impact in Patients with Subarachnoid Hemorrhage by Cisternal Lavage.

OBJECT: The initial amount of subarachnoid and ventricular blood is an important prognostic factor for outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH). In this comparative study of an unselected aSAH-population, we assess the modifiability of these factors by implementation of blood clearance by cisternal lavage. METHODS: All patients with aSAH treated in our department between October 2011 and October 2019 (8 years, n = 458) were included in our study. In the first 4-year period (BEFORE, n = 237), patients were treated according to international guidelines. In the second 4-year period (AFTER, n = 221), cisternal lavage methods were available and applied in 72 high-risk patients (32.5%). The cisternal and ventricular blood load was recorded by the Hijdra score. Multivariable regression models were used to assess the prognostic significance of risk factors, including blood load, in relation to common aSAH characteristics in both study groups. RESULTS: Worse neurological outcomes (mRS > 3) occurred in the BEFORE population with 41.45% versus 30.77% in the AFTER cohort, 6 months after aSAH (HR: 1.59, 95% CI 1.08-2.34, p = 0.01). Admission WFNS grade, comorbidities (Charlson Comorbidity Index), herniation signs, concomitant intracerebral hemorrhage, and the development of delayed cerebral infarction were strongly associated with poor outcome in both study groups. Intraventricular and cisternal blood load and, particularly, a cast fourth ventricle (Cast 4) represented strong prognosticators of poor neurological outcome in the BEFORE cohort. This effect was lost after implementation of cisternal lavage (AFTER cohort). CONCLUSION: Cisternal and ventricular blood load - in particular: a Cast 4 - represent important prognosticators in patients with aSAH. They are, however, amenable to modification by blood clearing therapies.

Double tubular minimally invasive spine surgery: a novel technique expands the surgical visual field during resection of intradural pathologies.

OBJECTIVE: A major challenge of a minimally invasive spinal approach (MIS) is maintaining freedom of maneuverability through small operative corridors. Unfortunately, during tubular resection of intradural pathologies, the durotomy and its accompanying tenting sutures offer a smaller operating window than the maximum surface of the tube's base. The objective of this study was to evaluate if a novel double tubular technique could expand the surgical visual field during MIS resection of intradural pathologies. METHODS: A total of 25 MIS resections of intradural extramedullary pathologies were included. A posterior tubular interlaminar fenestration was performed in all surgeries. A durotomy covering the whole diameter of the tubular base was the standard in all cases. After placement of two tenting sutures on each side of the durotomy and application of tension, the resulting surface of the achieved dura fenestration was measured after optical analysis of the intraoperative video. In the next step, a second tube, 2 mm thinner than and the same length as the first, was inserted telescopically into the first tube, resulting an angulated fulcrum effect on the tenting sutures. RESULTS: Optical surface analysis of the dura fenestration before and after the second tubular insertion verified a significant widening of the visual field of 43.1% (mean 18.84 mm2, 95% CI 16.8-20.8, p value < 0.001). There were no ruptured tenting sutures through the increased tension. Postoperative MRIs verified complete resection of the pathologies. CONCLUSIONS: Inserting a second tube telescopically during posterior minimally invasive tubular spinal intradural surgery leads to an angulated fulcrum effect on the dura tenting sutures which consequently increases the surface of the dura fenestration and induces a meaningful widening of the visual field.

How Safe Is Minimally Invasive Transforaminal Lumbar Interbody Fusion for Octogenarians?: A Perioperative Complication Analysis.

BACKGROUND: Technical advances in minimally invasive spine surgery have reduced blood loss, access trauma, and postoperative length of stay. However, operating on the susceptible group of octogenarians still poses a dilemma because of a plethora of age-related comorbidities. The aim of this study was to investigate the safety of minimally invasive surgery (MIS) transforaminal lumbar interbody fusion (TLIF) in octogenarians. METHODS: We conducted a retrospective single-center study of all patients over 80 years of age who, between March 2009 and February 2014, had undergone MIS TLIF. The primary outcome was recorded major and minor complications within 30 days of surgery. RESULTS: Twenty-one patients with an average age of 84.1 ± 2.7 years underwent MIS TLIF in 31 levels for degenerative lumbar disk disease with intolerable pain after failure of conservative treatment. Of the patients, 33.3% showed no perioperative complications. In the remaining 66.7%, 6 major complications and 24 minor complications occurred within 30 days of surgery. Two of these patients died within 30 days of surgery because of sepsis and pulmonary embolism (mortality rate 9.5%). CONCLUSIONS: Our study spotlighted the susceptible group of octogenarians and evaluated the safety of MIS TLIF. The perioperative morbidity for octogenarians undergoing MIS TLIF is substantial and even higher than for patients over 65 years of age. Two thirds of patients in this subgroup suffer at least 1 complication. The 30-day mortality rate was 9.5%. Therefore, it is advisable for these patients to exploit all available conservative options prior to surgery.