Non-invasive aspergillosis of the paranasal sinuses: CT and MRI findings

Aspergillosis is the most common fungal infection of the paranasal sinuses, and needs to be recognized because it requires surgical removal. Twenty proven cases of aspergillosis of the paranasal sinuses are reported here. CT was performed in all the cases and MRI in 2 cases. The maxillary sinus was affected in 19 patients and the sphenoid sinus in 1. Mycosis was unilateral in all but 1 of the cases. Foci of increased attenuation at CT were observed in 18 cases, with calcification in 10 cases and/or dental material in 13 cases. An increased bony wall thickness was observed in 16 cases. All the patients but 1 had at least one of the signs. At MRI the fungal mass displayed a hypointense signal on T1- and T2-weighted images. No enhancement was noted on post-contrast T1-weighted images. The diagnosis of paranasal sinus aspergillosis is suggested by the CT findings, when a hyperdense mass with calcifications and/or dental material is noted with thickening of the sinus wall. MRI may have a complementary diagnostic role in doubtful cases. Correspondence to: Y. Robert     

Radiodense concretions in maxillary sinus aspergillosis: pathogenesis and the role of CT densitometry

The purpose of this study was to investigate by CT the origin of radiodense maxillary sinus concretions and whether CT densitometry is effective in the prediction of maxillary sinus aspergillosis and in the differentiation of the origin of these concretions. In a prospective study in 21 patients with radiodense maxillary sinus concretions detected by radiography, a preoperative CT study of the paranasal sinuses and the concretions was undertaken. Additional scans of the upper alveolar ridge were also performed. Radiological findings were compared with clinical symptoms and with CT findings, especially CT densitometry of the sinus concretions and dental root-filling material. All patients underwent a functional Caldwell-Luc operation; histological and microbiological examinations were performed. Fifteen of the 21 patients (71.4 %) with radiodense concretions had a histological and microbiological diagnosis of sinus aspergillosis. The sinus concretions had CT densities higher than 2000 HU (Hounsfield units) in 15 patients and lower than 2000 HU in 6. Fourteen of 15 patients (93.3 %) with concretions having CT densities higher than 2000 HU had a postoperative diagnosis of maxillary sinus aspergillosis. The mean CT density of the sinus concretions in patients with maxillary sinus aspergillosis was 2868 HU (range 1870–3070 HU), and in patients without aspergillosis was 778 HU (range 228–2644 HU). The mean CT density of the dental root-filling material was 2866 HU (range 2156–3070 HU). Paranasal sinus CT with CT densitometry of a sinus concretion has a higher accuracy than standard radiography and clinical findings in the prediction of maxillary sinus aspergillosis (93.3 % vs 71.4 %). CT densitometry helps to confirm the dental origin of maxillary sinus concretions and to explain a possible dental pathogenesis of maxillary sinus aspergillosis.Correspondence to: F. X. Lenglinger     

Low-dose CT and inflammatory disease of the paranasal sinuses

Summary Computed tomography (CT) is the gold standard for exact delineation of inflammatory sinus disease, especially before endoscopic surgical treatment, and in cases of postoperative recurrences. In routine CT studies, the radiation dose to the patient is not negligible. Therefore, the authors evaluated prospectively the CT scans of 44 patients with inflammatory disease of the paranasal sinuses, to define the imaging ability of low-dose CT (i.e. 60 mA-3 s, 30 mA-3 s, and 30 mA-2 s), comparatively with the standard mAs settings (130 mA-3 s). In all cases, the exact extent of the disease was correctly assessed on each of the low-dose settings, with no false negative study. The increasing graininess of low mAs sections did not induce errors of interpretation, despite a less pleasant appearance to the eyes. In cases of extensive sinus disease, the thickness and integrity of the ethmoid septa were sometimes more difficult to evaluate on lowdose CT sections. The authors recommend the use of low mAs settings in the evaluation of inflammatory disease of the sinuses, complemented, if necessary, in cases of extensive abnormalities, by one or two sections obtained with standard mAs settings, focused on questionably abnormal bone septa.     

Proposal of a CT scoring system of the paranasal sinuses in diagnosing cystic fibrosis

The purpose of this study was to develop a paranasal sinus CT scoring system that could be used as a diagnostic tool to discriminate cystic fibrosis (CF) patients from control patients examined for sinonasal disease. The model should include as few and easily applicable criteria as possible, supported by statistical analyses and clinical judgement. We used data from 116 CF and 136 control patients. The CF patients were grouped according to the number of confirmed CF mutations: genetically verified (CF-2), or based on sweat testing and clinical findings alone (CF-1, CF-0). Nine paranasal sinus CT criteria, including development, pneumatisation variants and inflammatory patterns, were evaluated. The final model included three criteria: (a) frontal and (b) sphenoid sinus development, and (c) absence of three pneumatisation variants. This model discriminated CF-2 from controls with overlap of summed scores in only 8 of 206 patients. When this model was applied in the CF-1 and CF-0 groups, two populations seemed to exist. A larger group with summed scores overlapping that of the CF-2 group and a smaller group with summed scores overlapping that of the control group. We conclude that this CT scoring system may support, as well as exclude, a CF diagnosis in cases of diagnostic uncertainty. Electronic Publication     

霉菌性鼻窦炎的CT诊断（附8例分析）

目的：旨在认识霉菌性鼻窦炎ＣＴ表现的特征，以便作出准确的定性诊断。材料与方法：搜集经手术病理证实的霉菌性鼻窦炎８例，其中曲霉菌病５例，毛霉菌病２例，隐球菌病１例。对它们的ＣＴ征象结合病理改变进行回顾性分析。同时对本病与一般性炎症、肿瘤之间的鉴别诊断作了讨论。结果：以下ＣＴ征象可作秋诊断该病的重要依据：（１）病变为单侧性，对侧鼻腔鼻窦正常；（２）病变仅位于上颌窦或以上颌窦为主，累及同侧鼻腔及其他鼻窦     

霉菌性鼻窦炎的CT诊断

目的 探讨霉菌性鼻窦炎CT特征性表现及诊断价值。方法 回顾性分析12例经手术病理证实的霉菌性鼻窦炎CT表现，提出诊断和鉴别诊断要点。结果 霉菌性鼻窦炎主要CT表现有：病变为单侧性，对侧鼻窦正常；病变仅位于上颌窦或以上颌窦为主，累及其他鼻窦；病变窦腔密度增高，不均匀，内有小团状，砂粒状，条状极高密度区；可有鼻窦骨质破坏。结论 霉菌性鼻窦炎的CT表现上有特异性，CT是诊断该病有价值的方法。     

Mucoceles in the paranasal sinuses involving the orbit: CT signs in 43 cases

Summary The diagnostic value of computed tomography was verified in the study of mucoceles in the paranasal sinuses involving the orbit. The CT data on 43 patients with clinical suspicion of mucocele highlight the characteristic signs; 26 were found to have a mucocele at operation.     

Aggressive fibrous dysplasia of the maxillary sinus

Fibrous dysplasia is usually a slowly progressive, benign disease that develops over several years and presents with deformity or mild symptomatology. Five of 34 patients (ages 4–21 years), who were subsequently diagnosed histologically as having fibrous dysplasia of the maxillary sinus, rapidly developed soft tissue masses of the malar region over a period of less than 4 months with accompanying pain (2 patients) and nasal obstruction and exophthalmos (2 patients). Each was clinically suspected of having a sarcoma; two had been thought to have an osteofibrosarcoma on initial biopsy at outside hospitals. After resection, all lesions developed regrowth. At histopathologic examination, both initial and recurrent masses proved to be typical fibrous dysplasia with spicules of woven bone in cellular, sometimes vascular, fibrous tissue. No malignant degeneration was found.On conventional radiography, aggressive fibrous dysplasia produced opacification and expansion of the maxillary sinus and apparent disruption of its wall with an associated soft tissue mass. Computed tomography (CT) demonstrated voluminous heterogeneous masses with ground glass appearance, calcifications, areas of enhancement, low attenuation, cystic areas, and a thinned, sometimes interrupted, maxillary wall. Despite the aggressive clinical course for both initial and recurrent lesions, the CT findings of a ground glass mass with calcifications surrounded by a maxillary sinus wall, even if incomplete, can suggest the diagnosis of aggressive fibrous dysplasia.Deceased     

Aspergillosis of the paranasal sinuses

Summary The CT appearances of 13 cases of pathologically proven aspergillosis involving paranasal sinuses were reviewed. Symptoms included rhinorrhea, nasal obstruction, headache, facial pain and foul smell from the nose. At operation, these lesions appeared yellowish, brownish, grey or black in colour, and contained dirty or muddy material. Microscopic examination of the tissue removed showed anAspergillus ball with chronic inflammation but without invasion of the nasal or sinus mucosa in 6 cases, and tissue invasion with necrosis and inflammation in 7. The structures involved, in order of frequency, were: maxillary sinus, nasal cavity, ethmoid sinus, orbit and cavernous sinus. The orbit was involved in 2 cases, therefore categorized as invasive; the other 11 cases were non-invasive as judged by CT. Calcification was seen in the lesions of 9 cases. In most cases the adjacent bony structures showed areas of erosion and sclerosis. Aspergillosis should be suspected in the presence of a mass in the paranasal sinuses or nasal cavity with calcification within it, which may not appear solid or dense and is separate from the walls of the sinus.     

鼻咽癌侵犯鼻窦的MRI表现(附86例病例分析)

目的：分析鼻咽癌侵犯鼻窦的磁共振（MRI）表现,探讨MRI在诊断鼻咽癌侵犯鼻窦中的作用。方法：回顾分析鼻咽癌并鼻窦侵犯的86例患者的MRI表现。结果：MRI表现为窦壁破坏100%,窦壁黏膜增厚52.3%,窦腔内软组织肿块65.1%,鼻窦内侵犯病灶与鼻咽肿瘤相连97.7%,合并积液25.6%。横断面T1WI、T2WI、CE-T1WI所示病灶三者间差异无显著性意义,矢状面T1WI、冠状面FSIR和冠状面CE-T1WI示肿瘤侵犯蝶窦为100%,横断面T2WI和CE-T1WI对显示筛窦、上颌窦受侵最佳。结论：窦壁骨质破坏、连续性中断;窦壁黏膜不均匀性增厚;窦腔内肿块与鼻咽肿瘤主体相连,且有相同程度的强化;T1WI呈等或稍低信号,T2WI为等或稍高信号;增强扫描明显强化,是诊断鼻窦受侵犯的要点。因此,MRI的横断面T2WI、矢状面T1WI、冠状面FSIR及增强扫描在鼻咽癌鼻窦受侵犯的诊断中作用较大。     

鼻腔、副鼻窦几种良性肿瘤的CT表现

目的：探讨鼻空、副鼻窦几种良性肿瘤的CT诊断和鉴别。方法：对经手术和病理证实的49例（纤维瘤5例，神经纤维瘤6例，纤维血管瘤20例，骨化纤维瘤6例及内翻乳头状瘤12例）病人的临床，病理及CT表现进行分析对照。CT扫描采用轴位，层厚及层距5mm，部分病例用静脉闭注强后扫描，测量增强前后肿瘤的平均CT值。结果：各种肿瘤各自不同的病理改变决定了不同的CT特征，它们在发部位，病理变大小，形态，钙化，增强等方面均有不同，结论：根据CT表现可提示诊断，但需要与该部位的其它良性肿瘤及一些早期恶性肿瘤相鉴别。     

Chondromyxoid fibroma of paranasal sinuses: report of two cases presenting with nasal obstruction

 Chondromyxoid fibroma (CMF) is a rare, benign cartilaginous tumor that often occurs in the metaphyses of long bones. Tumors of the craniofacial bones are extremely rare and most often involve the mandible and the maxilla. This report presents the clinicopathological and radiological features of two unusual cases of CMF arising in the paranasal sinuses that presented with nasal obstruction. The tumors arose in the sphenoid and ethmoid sinuses and were treated by curettage and resection, respectively. One of the two patients was 20 days old, suggesting a possible congenital origin.     

基于CT扫描数据的鼻腔鼻窦三维模拟手术的研究

目的 研究基于CT扫描数据的鼻窦、颈内动脉、眶壁及病变组织三维(3D)重建模型指导鼻内镜手术的可行性及实用性.资料与方法 采集11例住院患者的鼻窦CT薄层扫描图像,利用自主研发的三维重建软件FitMe DICOM viewer对所采集数据进行图像分割和三维可视化重建,并评估重建质量及对手术的应用价值.结果 选择CT薄层扫描图像数据进行分割和重建,分割后的图像边界清晰、完整,数据无丢失.重建的结构清晰、连续,可以真实反映鼻窦、颈内动脉、眶壁及病变组织结构的实际情况,为术者提供符合空间想象的图像,以指导鼻内镜手术.结论 利用FitMe DICOM viewer软件对二维CT图像进行分割,方法简单实用,分割效果理想,重建后的3D模型三维效果逼真,立体感强,既能够显示鼻腔内部各结构的情况,又能准确反映鼻窦及病变组织与周围各结构的空间位置关系,为临床和教学奠定了基础.     

Orbital complications of functional endoscopic sinus surgery: MR and CT findings

AIM: To describe the radiological findings of ophthalmic complications during functional endoscopic sinus surgery (FESS) and correlate them with the clinical manifestations and mechanisms of injury. METHODS: This was a retrospective review of the clinical and cross-sectional imaging findings of 9 patients with orbital complications during FESS. RESULTS: The most common site of entry into the orbit during FESS was the lower medial orbital wall (7 of 9), followed by the inferior orbital wall, resulting in injury to the medial rectus (4 of 9) and, less frequently, the inferior rectus (2 of 9) or superior oblique muscles (1 of 9). Extensive scarring on imaging (3 of 9) was associated with global ocular motility dysfunction. In contrast, localized scarring (3 of 9) or extraocular muscle trauma (6 of 9) resulted in disturbance of eye movement in the direction of gaze from the injured site. CONCLUSIONS: Orbital magnetic resonance and computed tomography findings correlate very well with the abnormal eye movements clinically observed, and can assist in clarifying the cause of injury and guide surgical corrective management of patients suffering orbital complications from FESS. Radiologists should be familiar with the recent developments in FESS instrumentation as well as with the most commonly injured structures within the orbit.     

飞行人员鼻窦气压伤的临床诊治和医学鉴定

目的 总结飞行人员鼻窦气压伤的临床诊治和医学鉴定经验. 方法 整理、分析73例飞行人员鼻窦气压伤临床资料. 结果 ①Ⅱ_a类56例(仅有鼻窦气压伤),Ⅱ_c类17例(鼻窦气压伤+耳气压伤).②发生于额窦54例,上颌窦10例,筛窦3例,蝶窦2例,额窦+上颌窦和额窦+筛窦各2例.③原发性气压伤24例(由窦口本身病变所致),继发性气压伤49例(由窦口周围病变所致).④继发性鼻窦气压伤Ⅰ型(鼻腔结构异常型)15例、Ⅱ型(炎症型)25例、Ⅲ型(变态反应型)8例和Ⅳ型(肿瘤型)10例;其中7例两型并存,1例3型并存;窦内型7例、窦外型42例.⑤轻度34例(46.6%),重度39例(53.4%).⑥62例飞行合格,2例飞行暂时不合格,9例飞行不合格. 结论 额窦气压伤发生比例最高.对鼻窦气压伤进行分类、分型和分度具有重要的临床航空医学意义.继发性病变所占比例较高,炎症型是窦口周围病变的重要原因,重度鼻窦气压伤需要手术治疗,Ⅱ_c类气压伤是最易导致医学停飞的疾病.     

鼻腔鼻窦神经鞘瘤的CT和MRI表现

目的 探讨鼻腔鼻窦神经鞘瘤的CT和MRI表现,并评价2种影像检查方法的临床应用价值.方法 回顾性分析12例经组织学证实鼻腔鼻窦神经鞘瘤的影像资料,12例均做cT检查,10例做MR检查.结果 12例神经鞘瘤中良性11例,低度恶性1例;发生于鼻筛区4例,上颌窦3例,上颌窦、筛窦及蝶窦2例,上颌窦、鼻腔1例,蝶窦1例,后鼻孔1例;病变边界清楚,呈椭圆形4例,不规则形8例.CT表现:病变区轮廓扩大,相应鼻腔鼻窦骨质受压、变薄、移位,其中8例伴局部吸收,1例伴轻微侵蚀性破坏;平扫病变密度均匀10例,另2例其内可见低密度区,增强后2例病变显示不均匀强化.MRI表现:与脑实质比较,T1WI呈等信号,其中3例可见片状及结节状低信号,2例伴有片状高信号;T2WI呈不均匀等信号7例,稍高信号3例,其中2例伴有片状低信号;9例病变内可见点、片状高信号,其中6例伴有规整的结节状高信号,1例显示液-液面;增强后9例显示中度或显著不均匀强化,1例较均匀显著强化.2例行MR动态增强扫描,时间.信号强度曲线为平台型.6例伴有阻塞性鼻窦炎,T1WI为低信号,T2WI为高信号,增强后其内部不强化,边缘可见线状强化.MRI均清楚显示病变的范围和伴发的炎症.结论 骨质变形、变薄、吸收和MR T2WI所示斑片、结节状高信号并且增强后无强化为该病特征性表现;CT和MR两种影像检查方法联合使用能够对该病的诊断、治疗提供更全面的信息.     

Assessment of the lacrimal recess of the maxillary sinus on computed tomography scans

Objective

To assess the frequency of the lacrimal recess in the maxillary sinus (MS) in computed tomography (CT) of the paranasal sinuses.

Methods

CT of the paranasal sinuses (CT PNS) done in a total of 78 patients. According to the discoveries, the MS were classified in two types: anterior or lateral.

Results

41 CT PNS of 41 patients of a total of 78 patients preselected were excluded. 37 CT of the paranasal sinuses from 37 patients, in a total of 68 maxillary sinuses were studied. In the 33 right maxillary sinuses, 10 lacrimal recesses were found, 9 from male patients. Eleven left maxillary sinuses with lacrimal recess were found from a total of 35 left maxillary sinuses.

Conclusion

From the analysis of 68 MS, a frequency of 30.9% of lacrimal recesses in the maxillary sinuses in CT was observed.     

Virtual endoscopy of the nose and paranasal sinuses

The purpose of this study was to evaluate the applicability of virtual endoscopy (VE) in the region of the nose and paranasal sinuses on the basis of volume-rendered spiral CT data. Forty-five patients underwent a low-dose spiral CT of the sinuses. The data were transferred to a workstation running software for volume rendering (EasyVision, Philips Medical Systems, Eindhoven, The Netherlands). Six orthogonal views of the maxillary sinuses and the nasopharynx and a fly-through movie of the nose were calculated. Two radiologists evaluated the coronal reconstructions and virtual endoscopy with respect to detectability of pathology using a checklist comprising 10 points. In 30 patients who underwent subsequent endoscopic surgery, surgeons were asked to rank the degree of assistance of the preoperative virtual endoscopy. In general, virtual endoscopy was possible in all 45 patients. The mean time required for path definition and movie calculation for virtual endoscopy were 8 ( ± 2) min and 3 ( ± 1) min, respectively. Overall, more anatomical details were depicted on coronal reconstructions; however, a high degree of similarity between virtual endoscopy and the intraoperative impression was reported by the surgeons. We conclude that virtual endoscopy of the nose and paranasal sinuses may develop into a standard means to guide surgeons during endoscopic interventions. Received 17 September 1997; Revision received 23 December 1997; Accepted 29 December 1997     

Dynamic MR dacryocystography in patients with epiphora

Objective

The purpose of this study was to investigate the diagnostic value of dynamic MRI dacryocystography (dMR-DCG) for the assessment of nasolacrimal drainage system (NLDS).

Methods

The study population consisted of 35 patients with a history of epiphora. Each patient underwent bilateral dMR-DCG and conventional dacryocystography (DCG) to assess the NLDS. Two radiologists, who were unaware of the clinical data, evaluated the images separately for the level of obstruction at the nasolacrimal passage and the presence or absence of lacrimal sac dilatation. The findings from the dMRI-DCG and DCG images were compared. DCG was considered to be the gold standard imaging technique.

Results

dMRI-DCG had a sensitivity of 90.5% and a specificity of 89.3% to detect nasolacrimal passage. In 24 out of 70 NLDS that were assessed, there was 100% agreement between the dMRI-DCG and DCG images in the detection of the obstructed level in the nasolacrimal pathway. The lacrimal sac dilatation finding detected by DCG was not observed by dMRI-DCG in only two patients, in whom there was a prior history of dacryocystorhinostomy (DCR) operation. These findings suggest that dMRI-DCG has 94.3% sensitivity and 100% specificity for the diagnosis of lacrimal sac dilatation.

Conclusion

dMRI-DCG is an easily performed, minimally invasive imaging technique to identify the presence or absence of obstruction and its level, and lacrimal sac dilatation in the evaluation of NLDS. dMRI-DCG does not require the use of contrast material and ionizing radiation and provides functional information by depicting dynamic behaviour. Thus, dMRI-DCG could be useful as a reliable diagnostic imaging technique in many patients prior to surgery.     

螺旋CT多平面重组在副鼻窦检查中的应用

目的 :利用螺旋CT多平面重组技术探讨副鼻窦轴位扫描能否代替直接冠状位扫描。方法 :对 15例能合作的患者 ,均行副鼻窦轴位及冠状位扫描。使用美国GEProspeedFII双排螺旋CT机 ,层厚 5mm ,螺距 0 .75 ,连续横轴位扫描 ,利用多平面重组 (MPR)技术得到冠状位、矢状位重组图像 ;直接冠状位扫描获取冠状位图像 ;将同一患者的两组不同冠状位图像比较 ,主要观察各鼻窦窦壁及窦口。结果 :轴位扫描后重组所获图像亦能从多方位多角度观察 ,清楚显示各鼻窦及窦口。结论 :重组冠状位图像与直接冠状位扫描图像效果相同 ,可以取代直接冠状位扫描。避免后者检查时头部后仰造成的不适 ,患者容易接受 ,值得推广。