Akihito Kuboki

Endoscopic single-handed septoplasty with batten graft for caudal septum deviation

OBJECTIVE Septoplasty is usually performed with a Killian incision in Japan. However, the major drawback of the Killian incision is the inability to correct deviations of the caudal part of the septum. For patients with mild deviation of the caudal part of the septum but with a straight caudal end, we performed a modified Killian incision and used a batten graft to correct the deviated cartilage under endoscopy. The aim of this study was to evaluate the usefulness of our surgical technique for these cases. METHODS We prospectively collected data of 17 patients who underwent endoscopic septoplasty with a batten graft. Objective assessment by computed tomography and subjective assessment by questionnaire were performed before and 3 months after the surgery. RESULTS On computed tomography, the ratio of the area of the convex side to that of the concave side in the anterior portion of the nasal cavity was significantly improved after surgery (p<0.001). Subjective assessment revealed a significant improvement in nasal obstruction (p=0.002). There were no complications in this study. CONCLUSION The herein-described septoplasty with a batten graft is technically easy and considered to be useful for deviation of the caudal part of the septum in selected cases.

Assessment of suitable reference genes for RT–qPCR studies in chronic rhinosinusitis

Reverse transcription–quantitative polymerase chain reaction is a valuable and reliable method for gene quantification. Target gene expression is usually quantified by normalization using reference genes (RGs), and accurate normalization is critical for producing reliable data. However, stable RGs in nasal polyps and sinonasal tissues from patients with chronic rhinosinusitis (CRS) have not been well investigated. Here, we used a two-stage study design to identify stable RGs. We assessed the stability of 15 commonly used candidate RGs using five programs—geNorm, NormFinder, BestKeeper, ΔCT, and RefFinder. Ribosomal protein lateral stalk subunit P1 (RPLP1) and ribosomal protein lateral stalk subunit P0 (RPLP0) were the two most stable RGs in the first stage of the study, and these results were validated in the second stage. The commonly used RGs β-actin (ACTB) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were unstable according to all of the algorithms used. The findings were further validated via relative quantification of IL-5, CCL11, IFN-γ, and IL-17A using the stable and unstable RGs. The relative expression levels varied greatly according to normalization with the selected RGs. Appropriate selection of stable RGs will allow more accurate determination of target gene expression levels in patients with CRS.

Longer latency of sensory response to intravenous odor injection predicts olfactory neural disorder

A near loss of smell may result from conductive and/or neural olfactory disorders. However, an olfactory test to selectively detect neural disorders has not been established. We investigated whether onset latency of sensory response to intravenous odor injection can detect neural disorders in humans and mice. We showed that longer preoperative onset latency of odor recognition to intravenous odor in patients with chronic rhinosinusitis predicted worse recovery of olfactory symptoms following sinus surgery. The onset latency of the olfactory sensory neuron (OSN) response to intravenous odor using synaptopHluorin signals from OSN axon terminals was delayed in mice with reduced numbers of OSNs (neural disorder) but not with increased mucus or blocked orthonasal pathways (conductive disorders). Moreover, the increase in onset latency correlated with the decrease in mature OSN numbers. Longer onset latency to intravenous odor injection is a useful biomarker for presence and severity of olfactory disorders with neural etiology.

Prognostic factors for recurrence after endoscopic sinus surgery for chronic rhinosinusitis with nasal polyps.

OBJECTIVE In this study, we aimed to clarify the prognostic factors affecting the ethmoid condition during a long-term follow-up after endoscopic sinus surgery in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). METHODS Thirty-six patients with CRSwNP underwent surgery from December 2008 to February 2012. All surgeries were performed by one surgeon, and all patients were followed up for at least 2 years postoperatively. We investigated the association of postoperative endoscopic findings with clinical parameters, mucosal eosinophil count and mRNA expression of CCL11, IL-5, and IFN-gamma in nasal polyps. RESULTS Seventeen patients (47.2%) had severe mucosal edema, and the patency of each sinus was not confirmed during the >2-year follow-up. The mucosal eosinophil count and two eosinophil-associated factors, namely the CCL11 and IL-5 mRNA levels, were higher in the severe mucosal edema group than in the control group. The severe mucosal edema group was divided into two subgroups: the steroid-responsive and -resistant groups. Five patients (13.9%) had frank polyp formation because the oral steroids were less effective. The mucosal eosinophil count was significantly different among the four groups, including the control group (p=0.001); however, the CCL11, IL-5, and IFN-gamma mRNA levels were not significantly different. Although the IL-5 mRNA level was not significantly different among the four groups, it tended to increase when the sinus condition worsened. In the severe mucosal edema group, a higher IL-5 mRNA level was associated with earlier severe mucosal edema in the ethmoid cavity. CONCLUSION The IL-5 mRNA level is associated with the time of severe edema formation in the ethmoid cavity. This finding permits early intervention on the postoperative course and would prevent polyp recurrence.

Comparative analysis of surgical processes for image-guided endoscopic sinus surgery

AbstractPurposeThis study proposes a method to analyze surgical performance by modeling, aligning, and comparing surgical processes. This method is intended to serve as a means to support the enhancement of surgical skills for endoscopic sinus surgeries (ESSs). We focus on surgical navigation systems used in image-guided ESSs and aim to construct a comparative analysis method for surgical processes based on the information about the surgical instruments motion obtained from the navigation system. MethodsThe proposed method consists of the following three parts: quantification of surgical features, modeling of surgical processes, and alignment and comparison of surgical process models (SPMs). First, we defined time-series parameters using the navigation-based surgical data. Second, we created SPMs by applying the defined parameters and the relative positional information of the instruments to the patient’s anatomy. Third, we constructed a method to align and compare SPMs based on dynamic time warping with barycenter averaging.ResultsThe proposed method was validated on a dataset containing surgical data obtained by an optical tracking system from 14 clinical ESS cases. We evaluated the validity of the comparative analysis by aligning and comparing SPMs between experts and residents. The validation results suggested that the proposed method could achieve proper alignment of the SPMs and clarify the differences in surgical processes between experts and residents.ConclusionWe developed a method to enable a time-series comparative analysis of surgical processes based on the surgical data from the navigation system. This method can allow surgeons to identify differences between their procedures and reference procedures such as experts’ procedures.

Nasal silicone splints and quilting sutures using a septum stitch device following septoplasty: a prospective comparative study

PurposeAlthough nasal splints and trans-septal sutures are preferred for septal closure following septoplasty, quilting sutures, also known as continuous mattress sutures, are technically challenging and thus time consuming. Recently, the utility of a novel stitch device was demonstrated for quilting sutures; however, whether it contributes to the technical solution and time management of septal sutures remains unclear. This study aims to quantify the time and cost of septal closure following septoplasty by comparing nasal splints with quilting sutures using the septum stitch device.MethodsWe prospectively examined 23 patients who underwent septoplasty and assigned them to the following two groups: group 1, underwent the quilting suture for septal closure following septoplasty; group 2 underwent the nasal silicone splint method. We recorded the total operation time and surgical time for septal closure. Furthermore, we evaluated postoperative symptoms with Visual Analogue Scale (VAS) scores and compared the complication rate.ResultsWe observed no significant difference in the average of total operating time (P = 0.641) and the surgical time for septal closure (P = 0.886). Among postoperative symptoms, only nasal bleeding was significantly worse in group 1 on postoperative day 1 (P = 0.023). In addition, the occurrence of postoperative complications was insignificant between both groups.ConclusionsThe septum stitch facilitated safe and easy quilting suturing without significant increase of operation time.