Fine-cut Computed Tomography Scans Research Articles

A Comparison of Sphenoid Sinus Osteoneogenesis in Aspirin-Exacerbated Respiratory Disease.

BackgroundAspirin-exacerbated respiratory disease (AERD) is characterized by excessive leukotriene production, diffuse polyp burden and osteitic bone changes. These bony changes have not been previously characterized.ObjectiveThe aim of this radiographic study is to characterize the bony changes noted on computed tomography (CT) scans of the sphenoid sinus in patients with AERD compared to other diseased sinonasal inflammatory states and non-diseased controls.MethodsA retrospective review of 43 patients with clinically confirmed AERD were included and compared to 22 non-diseased, 9 allergic fungal sinusitis, and 43 chronic rhinosinusitis controls (23 without polyps and 18 with polyps). Comparative measurements were performed using fine-cut CT scans. Sites of comparison were the intersinus septum, the left and right lateral sphenoid wall, the roof, and left and right floor of the sphenoid sinus. Standardized measurements were averaged by two separate rhinologists.ResultsPatients with AERD had an average statistically significant increase in bone thickness compared to healthy and diseased controls in nearly every site with the most pronounced changes in the intersinus septum (p < 0.05).ConclusionPatients with AERD have significantly increased thickness of the sphenoid bone compared to control groups with the most pronounced difference in the intersinus septum. These findings may help clinicians increase suspicion for a diagnosis of AERD who clinically have diffuse nasal polyposis.

Does Systemic Administration of Parathyroid Hormone After Noninstrumented Spinal Fusion Surgery Improve Fusion Rates and Fusion Mass in Elderly Patients Compared to Placebo in Patients With Degenerative Lumbar Spondylolisthesis?

Prospective, randomized, double-blinded, placebo-controlled clinical trial. To evaluate whether 90-day subcutaneous injections with 20 μg teriparatide increases the volume and quality of the fusion mass compared to placebo based on 12-month postop fine cut computed tomography scans. The secondary objective is to evaluate whether parathyroid hormone (PTH) increases fusion rates compared to placebo. Few studies have investigated the effects of PTH on fusion in patients undergoing spinal arthrodesis. Early studies showed a more robust fusion mass with PTH after spinal fusion surgery. But the efficiency of PTH on noninstrumented spinal fusion surgery remains unclear. Patients with degenerative spondylolisthesis scheduled for noninstrumented posterolateral fusion were randomized to receive 90-day subcutaneous injections with 20 μg teriparatide (N = 41) or placebo (N = 46) in a 1:1 fashion. Fusion volume and quality was evaluated using 12-month postoperative fine cut computed tomography scans. The two groups were comparable in terms of age, sex, and numbers of levels operated. PTH treatment was well tolerated but provided no additional benefit versus placebo. Fusion rates, the mean volume, and robustness of the fusion mass were similar between the PTH and placebo groups. Ninety-day subcutaneous administration of 20 μg teriparatide did not increase fusion volume or improve the quality of the fusion mass in elderly patients compared to placebo after noninstrumented spinal fusion surgery for degenerative spondylolisthesis. 1.

A technique for pediatric chest wall reconstruction using custom-designed titanium implants: Description of technique and report of two cases

Purpose We present a surgical technique for chest wall reconstruction using custom-designed titanium implants developed for two female patients to provide both chest wall symmetry and adequate stability for staged breast reconstruction.MethodsA retrospective review was performed for two adolescent female patients with large chest wall defects who underwent the described technique. The etiology of the chest wall deficiency was secondary to Poland’s syndrome in one patient, and secondary to surgical resection of osteosarcoma in the other patient. For each patient, a fine-cut computed tomography scan was obtained to assist with implant design. After fabrication of the prosthesis, reconstruction was performed though a curvilinear thoracotomy approach with attachment of the implant to the adjacent ribs and sternum. Wound closure was obtained with use of synthetic graft material, local soft tissue procedures, and flap procedures as necessary.ResultsThe two patients were followed post-operatively for 35 and 38 months, respectively. No intra-operative or post-operative complications were identified. Mild scoliosis that had developed in the patient following chest wall resection for osteosarcoma did not demonstrate any further progression following reconstruction.ConclusionsWe conclude that this technique was successful at providing a stable chest wall reconstruction with satisfactory cosmetic results in our patients.

Anterior Lumbar Interbody Fusion as a Salvage Technique for Pseudarthrosis following Posterior Lumbar Fusion Surgery.

Study Design Retrospective analysis of prospectively collected observational data. Objective To assess the safety and efficacy of anterior lumbar interbody fusion (ALIF) as a salvage option for lumbar pseudarthrosis following failed posterior lumbar fusion surgery. Methods From 2009 to 2013, patient outcome data was collected prospectively over 5 years from 327 patients undergoing ALIF performed by a single surgeon (R.J.M.) with 478 levels performed. Among these, there were 20 cases of failed prior posterior fusion that subsequently underwent ALIF. Visual analog score (VAS), Oswestry Disability Index (ODI), and Short Form 12-item health survey (SF-12) were measured pre- and postoperatively. The verification of fusion was determined by utilizing a fine-cut computed tomography scan at 12-month follow-up. Results There was a significant difference between the preoperative (7.25 ± 0.8) and postoperative (3.1 ± 2.1) VAS scores (p < 0.0001). The ODI scale also demonstrated a statistically significant reduction from preoperative (56.3 ± 16.5) and postoperative (30.4 ± 19.3) scores (p < 0.0001). The SF-12 scores were significantly improved after ALIF salvage surgery: Physical Health Composite Score (32.18 ± 5.5 versus 41.07 ± 9.67, p = 0.0003) and Mental Health Composite Score (36.62 ± 12.25 versus 50.89 ± 10.86, p = 0.0001). Overall, 19 patients (95%) achieved successful fusion. Conclusions Overall, our results suggest that the ALIF procedure results not only in radiographic improvements in bony fusion but in significant improvements in the patient's physical and mental experience of pain secondary to lumbar pseudarthrosis. Future multicenter registry studies and randomized controlled trials should be conducted to confirm the long-term benefit of ALIF as a salvage option for failed posterior lumbar fusion.

Intra-articular Osteoid Osteoma of the Proximal Ulna

Osteoid osteoma is a common benign osteogenic bone neoplasm characterized histologically by increased osteoid tissue formation with an intracortical nidus surrounded by cortical thickening and vascular fibrous stroma and sclerosis. The clinical presentation classically includes severe nocturnal pain that is improved with nonsteroidal anti-inflammatory drugs. Younger men (second and third decades) have the highest incidence, with the most frequent sites of involvement being the long bones or axial skeleton. Osteoid osteoma may be missed due to the lesion occurring in an atypical location or due to failure to obtain advanced imaging studies such as computed tomography (CT). Intralesional or wide excision, or CT-guided radiofrequency ablation if available, leads to predictable and rapid pain relief. The authors report the case of a 24-year-old man who had a painful flexion contracture of his dominant right elbow for 1.5 years, secondary to an intra-articular osteoid osteoma. Attempted motion, passive or active, produced a marked exacerbation of pain. Previous surgeries, including an elbow synovectomy and an ulnar nerve transposition, had been unsuccessful in relieving his pain. Plain radiographs demonstrated a small area of periosteal thickening adjacent to the sublime tubercle. Fine-cut CT scan demonstrated an osteoid osteoma within the articular surface of the trochlear notch of the olecranon, adjacent to the sublime tubercle. Because of a perceived risk to the surrounding articular cartilage, CT-guided radiofrequency ablation was not performed. Wide en bloc surgical excision of the nidus was performed, with complete resolution of pain and rapid return to normal function.

Reformatted Computed Tomography to Assess the Internal Nasal Valve and Association With Physical Examination

To assess the cross-sectional area and angle of the internal nasal valve more accurately by reformatting computed tomography (CT) scans of the nasal airway according to a more appropriate orientation than scans traditionally sectioned in the coronal plane and then to compare the results with clinical data on the nasal valve obtained from physical examination. We performed a retrospective review of the medical records of 24 rhinoplasty patients treated at a private practice facial plastic surgery office affiliated with a tertiary care university hospital. The patients had fine-cut (0.75-mm section) CT scans ordered for nasal airway obstruction or nasal valve compromise at the same institution. These patients were evaluated from January 1, 2000, through December 31, 2010. The previously acquired CT scans were reformatted to obtain sections through the internal nasal valve at a more appropriate orientation. The internal nasal valve cross-sectional area and valve angle were measured through a standardized section (1 cut immediately anterior to the head of the inferior turbinate) from the reformatted scans. The cross-sectional area was also measured through the same point on the traditionally oriented CT scan, and the values were compared. The results from each patient's scan were compared with data from the patient's medical record and analyzed against the patient's preoperative modified Cottle examination findings. The CT scans oriented in the reformatted plane through the internal nasal valve provided a narrower valve angle than the traditionally oriented CT scans and more closely approximated the hypothesized true value of the internal nasal valve of 10° to 15° (P < .001). In a comparison of the same-side internal nasal valve angle and cross-sectional nasal valve area between the 2 different CT scan orientations, a statistically significant difference in the internal nasal valve angles between the 2 scan orientations was discovered, but this finding did not reach significance when distinguishing the nasal valve cross-sectional area. Finally, no correlation was found with regard to the preoperative modified Cottle maneuver scores for the internal nasal valve angle and cross-sectional valve area values in either scan orientation. Precise preoperative evaluation of the internal nasal valve is critical to the workup for reconstruction or repair of problems that involve this area. Although tools such as acoustic rhinometry exist to evaluate the cross-sectional area of the nasal valve, many rhinoplasty surgeons do not have access to this expensive equipment. A CT scan with reformatting in the proper plane of the internal nasal valve can provide the surgeon with improved anatomical information to assess that region. With this in mind, however, the surgeon should always perform a thorough preoperative physical examination and treat the patient and his or her symptoms, not the imaging studies, when considering a candidate for a surgical intervention.

Frontal Infundibular Cells: Pathway to the Frontal Sinus

A frontal infundibular cell (FIC) is an uncommon anatomic variant of an anterior ethmoid pneumatization that originates from the frontal recess and typically extends into the lumen of the frontal sinus ostium. FICs may show several anatomic variants that impact the anatomy of the frontal recess. Familiarity with these variants is required for safe endoscopic sinus surgical procedures. We conducted a retrospective chart review, examining 1,040 frontal recesses in 520 adults with no frontal sinus disease, to explore the anatomy of the healthy frontal recess and to describe the prevalence of FICs in patients without a history of conditions that cause frontal pneumatization. Review of axial and coronal computed tomography data, which were reformatted for sagittal reconstruction, was performed at a computer workstation. Bent and Kuhn's classification was used to define types of FICs. We identified 167 patients (32.1%) as having unilateral or bilateral FICs. Type I infundibular cells were the most common type (found in 15.7% of the entire study population). Type II and type III FICs were found in 3.8% and 12.1%, respectively; type IV FICs were present in 0.4%. The FIC has not been emphasized as an important potential cause of frontal sinus obstruction in the radiology literature, but clinicians should specifically watch for it on all routine computed tomography of the frontal sinus. Fine-cut computed tomography scans aid in the identification of each individual cell and allow the surgeon to formulate a clear and precise surgical plan. A surgical plan with a thorough understanding of the anatomy enables confident dissection of this complex and difficult area.

Optimal Trajectory for the Atlantooccipital Transarticular Screw

Radiologic evaluation of computed tomography (CT) scans using screw insertion simulation software. To investigate the optimal entry point and trajectory of atlantooccipital transarticular screws. To our knowledge, no large series focusing on the placement of atlantooccipital transarticular screws have been published. We used 1.0-mm sliced CT scans and 3-dimensional screw trajectory software to simulate 4.0-mm screw placement. Four entry points were evaluated. Screw placement success rate, safe range of medial angulation, and screw length using each entry point were determined. CT scans of 126 patients were evaluated, for a total of 252 screws for each entry point. On simulation, the 2 lateral entry points showed significantly higher success rates and safe range of medial angulation than the 2 middle points. The 2 lateral entry points had similar success rates (98.0% for anteriolateral (AL) point and 97.6% for posteriolateral (PL) point). Although the safe range of medial angulation was significantly wider for the AL point (26.1 degrees) than for the PL point (23.7 degrees), the screw lengths were significantly longer for the PL point (32.6 mm) than for the AL point (29.4 mm). For both points, 30 degrees of medial angulation led to highest rate of successful screw placement, but the rate was only 79.4% and 80.2%, respectively. Although there was no significant difference in success rates between AL and PL points, PL is likely the best entry point. Although 30 degrees medial and approximately 5 degrees upward angulation led to the highest rate of successful screw placement, the rate was only around 80%. Given the wide individual variation, we recommend that a preoperative 3-dimensional CT scan be obtained when attempting atlantooccipital transarticular screw fixation.

Two-year fusion and clinical outcomes in 224 patients treated with a single-level instrumented posterolateral fusion with iliac crest bone graft

Background context Reported fusion rates for spine fusions using iliac crest bone graft (ICBG) vary between 40% and 100% because of different fusion techniques, patient comorbidity, diagnosis and assessment criteria. Purpose We report two-year results of single-level instrumented posterolateral fusions evaluated with radiographs, fine-cut computed tomography (CT) scans with reconstructions and outcome measures. Study design/ setting Retrospective analysis of data from a prospective multicenter randomized clinical controlled trial. Patient sample Patients with various degenerative diagnoses enrolled in the control arm of a Food and Drug Administration (FDA)-regulated, multicenter trial of single-level decompression and posterolateral fusion for degenerative lumbar disease. Outcome measures Short Form-36 (SF-36), Oswestry Disability Index (ODI), Numeric Rating Scales (0–20) for back, leg, and graft site pain, CT scans, anteroposterior and lateral flexion/extension radiographs. Methods Patients enrolled in an FDA-regulated, multicenter trial at 29 sites with degenerative lumbar disease treated with single-level instrumented posterolateral fusion with ICBG were included in the analysis. Demographic and surgical data were collected. Clinical outcomes were followed using standard metrics. Fusion was assessed by independent radiologists at 6, 12, and 24 months postoperatively. Two fusion criteria were compared: anteroposterior and flexion/extension radiographs to assess motion and bridging bone, with CT scans as needed to confirm bridging bone; and CT scan assessment for bridging bone only. Results One hundred ninety-four of 224 subjects (86.6%) completed the study. The mean operative time was 2.9 hours with a blood loss of 448.6 mL. The average graft volume was 36.3 mL. There were 21 (9.4%) wound infections, 18 (8.0%) incidental durotomies, 3 (1.3%) implant displacements, 2 (0.9%) malpositioned implants, and 17 (7.6%) graft-related complications. Twenty-seven patients (13.9%) required reoperation, the majority for nonunions. Fusion rates based on radiographs with selective CTs at 6, 12, and 24 months were 65.3%, 82.5%, and 89.3%, respectively. Fusion rates based on bridging bone on CT scans were 56.1%, 71.5%, 83.9%, respectively. Two-year improvement for all outcome measures was significant (p<.001)—ODI 25.3, SF-36 Physical Component Score (PCS) 12.2, back pain 7.9, and leg pain 7.1. Two years postoperatively, 60% of patients complained of graft site pain (mean pain score=8.5). Conclusion In a large series of patients who had primary single-level instrumented posterolateral fusion with ICBG, evidence of bridging bone on fine-cut CT scans improved with time to 83.9% at 24 months. Significant improvement from baseline was noted in all clinical outcome measures at all time intervals with 75% achieving minimum clinically important difference (MCID) for ODI and 66% achieving MCID for SF-36 PCS.

RhBMP-2 Versus Iliac Crest Bone Graft for Lumbar Spine Fusion

Prospective randomized controlled trial of rhBMP-2/ACS (Infuse bone graft) versus iliac crest bone graft (ICBG) for lumbar spine fusion in patients over 60 years of age. To report on clinical, radiographic, and economic outcomes, at 2-year follow-up, in patients treated by posterolateral lumbar fusion with rhBMP-2/ACS versus ICBG. RhBMP-2/ACS is widely used "off-label" for posterolateral spinal fusion. Despite encouraging initial reports, outstanding issues include the need for evidence regarding safety and efficacy in an older population; and an assessment of cost-effectiveness. Patients over 60 years old were randomized to rhBMP-2/ACS (n = 50) or ICBG (n = 52). Oswestry Disability Index, Short Form-36, and numerical rating scales for back and leg pain were determined preoperatively and at 6, 12, and 24 months postoperatively. Fusion was evaluated by fine-cut computed tomography scan 2 years postoperatively by 3 reviewers. All in-patient and subsequent out-patient event costs were recorded by a dedicated hospital coder. Two-year postoperative improvement in Oswestry Disability Index averaged 15.8 in the rhBMP-2/ACS group and 13.0 in the ICBG group. Mean improvement in Short Form-36 physical component score was 6.6 in the rhBMP-2/ACS group and 7.5 in the ICBG group. There were 20 complications in the ICBG group and 8 complications in the rhBMP-2/ACS group (P = 0.014). Sixteen ICBG and 10 rhBMP-2/ACS patients required additional treatment for persistent back or leg symptoms. Two rhBMP-2/ACS patients had revision procedures, 1 for nonunion. Eight patients in the ICBG group had revision procedures, 5 for nonunion. Mean fusion grade on computed tomography scan was significantly (P = 0.030) better in the rhBMP-2/ACS (4.3) compared with the ICBG group (3.8). Mean cost of the initial admission was $36,530 in the rhBMP-2/ACS group and $34,235 in the iliac crest bone graft (ICBG) group. Total cost of care over 2 years was $42,574 for the ICBG group and $40,131 for the rhBMP-2/ACS group. RhBMP-2/ACS is a viable ICBG replacement in older patients in terms of safety, clinical efficacy, and cost-effectiveness.

Reliability and accuracy of fine-cut computed tomography scans to determine the status of anterior interbody fusions with metallic cages

Background context Computed tomography (CT) scan has been shown to be more accurate than radiographs in evaluating anterior interbody fusion but may still over-read the extent of fusion. Purpose To assess the reliability and accuracy of fine-cut CT scans with reconstructions in evaluating anterior lumbar interbody fusion (ALIF) with metallic cages using surgical exploration as the reference standard. Study design Accuracy of a diagnostic test referenced to the gold standard. Patient sample A total of 49 patients and 69 surgical levels. Outcome measures Evaluation of fine-cut CT scans for evidence of fusion with subsequent surgical exploration as the reference standard. Methods Forty-nine patients who underwent ALIF with metallic cages over 69 levels, who had a fine-cut CT scan before revision were included. Five spine surgeons unaware of the findings on surgical exploration evaluated pre-revision CT scans, classified these as fused or not; and determined the presence of a “sentinel sign” and a “posterior sentinel sign.” Kappa coefficients for interobserver reliability, sensitivity, and specificity to detect fusion were determined. Results There were 26 males and 23 females with a mean age of 43 years. There were 27 smokers. Average time from index to revision surgery was 22 months. Interobserver kappa for classification as fused or not was 0.25 with 70% to 97% sensitivity and 28% to 85% specificity. The interobserver kappa for the sentinel sign was 0.34 with 13% to 33% sensitivity and 77% to 92% specificity. The interobserver kappa for the posterior sentinel sign was 0.23 with 33% to 87% sensitivity and 56% to 90% specificity. Conclusions Raters generally overstated fusion with low specificities across raters and low consensus specificity. Overall accuracy of the posterior sentinel sign (74%) was higher than the sentinel sign (61%). The low kappa value indicates fair reliability. In patients with metallic interbody devices, surgeons should be cautious about interpreting the findings on fine-cut CT scans whether using a general assessment of the fusion, the sentinel sign, or the posterior sentinel sign.

The Efficacy of rhBMP-2 for Posterolateral Lumbar Fusion in Smokers

Retrospective review of prospectively collected data, as part of an IRB-approved, FDA-regulated, randomized, nonblinded IDE trial of rhBMP-2 matrix for lumbar spinal fusion. The purpose of this study is to examine the influence of smoking on fusion rate and outcome in a large series of patients treated with an rhBMP-2 matrix (AMPLIFY) or iliac crest bone graft as part of a randomized IDE trial for single-level lumbar fusion. Preclinical studies suggest that bone morphogenetic proteins (BMPs) are able to reverse the negative influence of nicotine on fusion healing in animal models. It remains unclear if a similar benefit will be seen in humans, and if so, what formulation and amount of BMP will be required to achieve that improvement. We reviewed the clinical and radiographic records of 148 patients who underwent single-level instrumented lumbar fusion at three spine centers as part of an ongoing FDA-regulated IDE trial. Clinical outcome measures included Oswestry Disability Index, SF-36, back, and leg pain scores. Radiographic measures were plain radiographs with flexion-extension views and fine cut computed tomography scans with sagittal and coronal reconstruction. Fusion success was determined by independent radiologist readings. At 2 years postoperatively, solid fusion was demonstrated in all 55 nonsmokers in the rhBMP-2 group (100%). Successful fusion was seen in 20 of 21 smokers in the rhBMP-2 group (95.2%). Fusion was achieved in 48 of 51 nonsmokers in the iliac crest bone graft (ICBG) group (94.1%), but only 16 of 21 smokers (76.2%) in the ICBG group. The results of this study suggest that rhBMP-2 may enhance fusion rate in cigarette smokers undergoing single-level instrumented posterolateral lumbar fusion. Despite the improvement in fusion rate with rhBMP-2, clinical outcomes measures were still adversely affected in smokers.

Letters to the Editor: Reply

Reply: We agree with Albisinni and Malaguti's comments regarding the use of fine-cut computed tomography (CT) when trying to localize the nidus of an osteoid osteoma. At our institution, we use fine-cut CT scans in at least two planes when localizing the tip of the electrode to assure its precise position. This is important not only to observe the location of the tip relative to the nidus but also to assess the position of the surrounding bone and soft tissues relative to the electrode. In addition, although we understand the difficulty with treating a previously excised osteoid osteoma with radio-frequency ablation, as was mentioned in the Discussion of our case report, all the options were discussed with the patient and we decided to perform radiofrequency ablation. Perhaps successful treatment using radiofrequency ablation in this circumstance is more difficult because the nidus is hard to see on CT scans after previous procedures, as mentioned by Albisinni and Malaguti. The nidus in our case was identified as seen in Figure 1 in the original report,2 and a biopsy was performed with an 11-gauge needle before the radiofrequency probe was placed, as stated in our response to Cantwell and Eustace's letter to the editor.1 The use of ice on the overlying skin, mentioned by Albisinni and Malaguti, when the osteoid osteoma nidus lies in a subcutaneous location, such as the anterior portion of the proximal tibia, is an appealing way of minimizing thermal injury to the superficial tissues. In addition, Albisinni and Malaguti recommend, as we do, that the cannula is away from the electrode tip to avoid thermal injury to the tissue surrounding the cannula.2 Taking into account the size and depth of the target lesion and using an appropriate electrode for that lesion are also measures to limit thermal injury that we previously mentioned.2 Christian M. Ogilvie, MD Department of Orthopaedic Surgery, Pennsylvania Hospital at the University of Pennsylvania, Philadelphia, PA Joseph J. King, MD Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA

Diagnostic Accuracy and Reliability of Fine-Cut CT Scans With Reconstructions to Determine the Status of an Instrumented Posterolateral Fusion With Surgical Exploration as Reference Standard

Accuracy of a diagnostic test referenced to the gold standard. This study evaluated the reliability and accuracy of fine-cut computed tomography scans with coronal and sagittal reconstructions to determine the status of an instrumented posterolateral fusion by using surgical exploration as the reference standard. There is still a need for a reliable and accurate noninvasive method to determine the status of a spinal fusion. Three spine surgeons reviewed 93 prerevision fine-cut CT scans over 163 fused levels of consecutive patients who had revision surgery after an instrumented posterolateral lumbar fusion. The facet joints and posterolateral gutters at each level were classified as fused or not. The surgeons were unaware of the findings on surgical exploration. Interobserver variability and likelihood ratios for a solid fusion when both, one, or none of the facets and when both, one, or none of the posterolateral gutters were fused, were calculated. There were 42 males and 51 females with a mean age of 57 years (range, 19-86 years) at revision. On exploration, there were 32 (19.6%) nonunions over 163 levels. The kappa for interobserver variability for evaluating facet fusions (0.42) was moderate and for posterolateral fusions (0.62) was substantial. The probability of a solid fusion on exploration was higher when both posterolateral gutters were fused on CT scan (89%) than when both facets were fused on CT scan (74%). When both facets and both posterolateral gutters were fused on CT scan, the probability of a solid fusion on exploration is 96%. The absence of fusion of one or both facets or one posterolateral gutter were poor predictors of nonunion on surgical exploration. The CT scan reading of either one or both posterolateral gutters fused or both facets fused were moderately predictive of a solid fusion on surgical exploration. Fine-cut CT scans with reconstructions are moderately predictive of the presence of nonunion when both facets are not fused.

Unilateral rhinorrhea and nasal obstruction in an adult

choanal atresia is an uncommon malformation, consisting of congenital blockage of one of both choanae. Symptomatology varies according to the type of atresia and the age of the patient. The bilateral, or complete, form presents in newborns as respiratory distress while unilateral, or incomplete, forms present in older children or adults. a 16-year-old girl presented with a lifelong history of right-sided nasal blockage and unilateral watery rhinorrhea. The rhinorrhea increased when the patient bent her head forward. Treatment with antihistamines and topical nasal corticosteroid sprays produced little improvement. The patient's previous medical history was unremarkable except for the expulsion of a coagulated mass through the right nostril a few days after birth, and event that provoked her symptoms. Physical examination was normal except for excoriation of the right external nasal margin. Anterior rhinoscopy revealed watery rhinorrhea, erythematous mucosa in the right nasal cavity and deviated nasal septum. No nasal masses or polyps were found. Physical examination confirmed the absence of ventilation in the right nasal airway and nasal endoscopy indicated right choanal obstruction. skin prick tests with aeroallergens were positive for grass pollen and negative for all other allergens tested (mites, moulds, latex, and epithelia). Total IgE was normal (9 IU/ml). No eosinophilia was detected in the nasal secretion specimen. The results of laboratory tests including complete blood count and differential, erythrocyte sedimentation rate, and biochemical parameters were normal. The glucose level in nasal secretion was 4.6 mg/dl. X-rays of the paranasal sinuses and cavum showed no anomalies. Axial fine-cut computed tomography scans (3 3 mm) revealed choanal obstruction with bony and membranous components. a diagnosis of congenital choanal atresia should be considered in cases of unilateral blockage and rhinorrhea. Nasal endoscopy and computed tomography scans are essential to establish diagnosis.