Lateral Pedicled Nasoseptal Flaps for Endoscopic Draf III Procedure in Patients With Frontal Sinus Inverted Papilloma

Study Overview
=================
Brief Summary
-----------------
This is a retrospective case series study. The Draf III procedure exposes excessive bare bone, resulting in frontal ostium restenosis and surgical failure. For tumors originating from frontal sinus, especially inverted papillomas, abrading of bone around frontal ostium often exacerbate the restenosis. This study aims to retrospectly recruit patients with frontal sinus inverted papillomas who received Draf III procedure in our center during 2015-2021 and investigated the efficacy of a novel pedicled nasoseptal flap for endoscopic frontal sinus procedures. Each subject received a CT and magnetic resonance imaging (MRI) scans before operation. The subjects were followed up postoperative for at least 12 months to check the epithelization status and whether the neo-ostium were patent.

Detailed Description
-----------------
The standard Draf III procedure was performed as described by Gross and Wormald using an outside-in technique. The cranial portion of the nasal septum was removed, and the frontal process of the maxilla and frontal beak were carefully abraded, resulting in the frontal T. Distinct to the procedure of Gross and Wormald, the frontal T was then lowered to the first branch of the anterior ethmoidal artery instead of the first olfactory fibre. Tumors were totally resected under endoscope and lateral pedicled nasoseptal flaps were applied for covering the exposed bone around frontal neo-ostium. The pedicled nasoseptal flaps were applied in the experimental group and no flap was applied in the control group. The pedicle of the flap was designed to be on the frontal process of the lateral nasal wall. The lateral anterior incision was approximately 1 cm anterior to the maxillary line, with the medial anterior limit in parallel on the septum. The lateral posterior limit was the maxillary line and medial posterior limit parallel to the anterior limit where the first branch of the anterior ethmoidal artery arises on ethmoidal roof. The lower limit of the septal part was at the level of the lower border of the middle turbinate. The flap was carefully elevated from the cartilage and bone, particularly the supra-axillary and olfactory fossa part. The flap was then persevered posteriorly in the nasal floor or maxillary sinus for subsequent use. The contralateral flap was harvested and preserved in a similar manner. Type 1 flaps consisted of mucosa over the lateral nasal wall, and type 2 flaps consisted of the aforementioned mucosa and corresponding septal mucosa. All patients were followed up for at least 12 months, and the nasal cavity was assessed and cleaned regularly under endoscopy. The neo-ostium section area was compared to that at the end of surgery. Epithelization was identified if the neo-ostium were smooth without edema, discharging or crusting after surgery under endoscope. The time required for epithelialization of each patient was also recorded. Restenosis was defined as >50% reduction in the section area at 12 months postoperatively.

Official Title
-----------------
Lateral Pedicled Nasoseptal Flaps for Endoscopic Draf III Procedure in Patients With Frontal Sinus Inverted Papilloma

Conditions
-----------------
Draf III Procedure, Naso-septal Flap, Inverted Papilloma

Intervention / Treatment
-----------------
* Procedure: Draf III procedure with lateral pedicled nasoseptal flaps applied
* Procedure: Draf III procedure without any flap applied


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Adult patients with bilateral frontal inverted papilloma who received a endoscopic endonasal Draf III surgery. Ages range from 18-85 years old. Preoperative CT and MRI scanning show favourable frontal sinus pneumatization. Patients who are willing to following up regularly with good compliance. Exclusion Criteria: Patients who had undergone prior partial septectomy or septal perforation. Patients who can't finish a regular 1-year follow-up.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Procedure/Surgery: lateral pedicled nasoseptal flaps applied in Draf III procedure<br>The standard Draf III procedure was performed as described by Gross and Wormald using an outside-in technique. The cranial portion of the nasal septum was removed, and the frontal process of the maxilla and frontal beak were carefully abraded, resulting in the frontal T. Distinct to the procedure of Gross and Wormald, the frontal T was then lowered to the first branch of the anterior ethmoidal artery instead of the first olfactory fibre. Tumors were totally resected under endoscope and lateral pedicled nasoseptal flaps were applied for covering the exposed bone around frontal neo-ostium. Type 1 flaps consisted of mucosa over the lateral nasal wall, and type 2 flaps consisted of the aforementioned mucosa and corresponding septal mucosa. | Procedure: Draf III procedure with lateral pedicled nasoseptal flaps applied<br>* The standard Draf III procedure was performed as described by Gross and Wormald using an outside-in technique. The cranial portion of the nasal septum was removed, and the frontal process of the maxilla and frontal beak were carefully abraded, resulting in the frontal T. Distinct to the procedure of Gross and Wormald, the frontal T was then lowered to the first branch of the anterior ethmoidal artery instead of the first olfactory fibre. Type 1 flaps consisted of mucosa over the lateral nasal wall, and type 2 flaps consisted of the aforementioned mucosa and corresponding septal mucosa. After Draf III procedure, type 1 flaps were used to cover the bare bone of the ipsilateral frontal process and part of the ipsilateral anterior frontal table, which also constituted the bare bone area of the Draf II procedure. Type 2 flaps were used to cover for the bare bone of the ipsilateral frontal process and bilateral anterior or posterior frontal table.<br>|
| Procedure/Surgery: no flaps applied in Draf III procedure<br>The standard Draf III procedure was performed as described by Gross and Wormald using an outside-in technique. The cranial portion of the nasal septum was removed, and the frontal process of the maxilla and frontal beak were carefully abraded, resulting in the frontal T. Distinct to the procedure of Gross and Wormald, the frontal T was then lowered to the first branch of the anterior ethmoidal artery instead of the first olfactory fibre. Tumors were totally resected under endoscope and no flaps were applied. | Procedure: Draf III procedure without any flap applied<br>* The standard Draf III procedure was performed as described by Gross and Wormald using an outside-in technique. The cranial portion of the nasal septum was removed, and the frontal process of the maxilla and frontal beak were carefully abraded, resulting in the frontal T. Distinct to the procedure of Gross and Wormald, the frontal T was then lowered to the first branch of the anterior ethmoidal artery instead of the first olfactory fibre.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time needed for epithelization | Epithelization was defined if the neo-ostium and the fused frontal sinus were smooth without edema, discharging or crusting after surgery under endoscope. Time needed for each subject was recorded. | within 12 months postoperatively | 
| Whether or not the frontal neo-ostium was restenosed | Patients were checked under endoscope, and restenosis of neo-ostium was defined as a reduction of more than 50% in the section area compared to that at the end of surgery. | 12 months postoperatively |