The accuracy of limited CT in the evaluation of chronic rhinosinusitis and for endoscopic sinus surgery: a multicenter study.

Objective: To compare the accuracy of Limited CT with the Full CT as the standard evaluation for inflammatory disease of PNS and the identification of anatomical variations. Methods: From Full CT of PNS, Limited CT were retrieved. Computerized tomographic scans were performed for the preoperative planning of endoscopic sinus surgery (ESS) in 3 tertiary care university hospitals in Thailand. The two types of examinations were reviewed independently and in random order by two experienced radiologists. Using Full CT as the standard, the accuracy of Limited CT were evaluated for 1) the radiologic staging of rhinosinusitis (Lund-Mckay scoring system) and 2) the anatomic variations which are an important landmark for surgical operations in rhinosinusitis. Results: Totally 132 patients were included. Two hundred and sixty four half-faces were reviewed. Lund-McKay radiographic sinus staging system showed 97-99% specificity except for the ostiomeatal complex region. Regarding anatomic variation, Limited CT was able to yield accurate results for the frontal cell type II-IV, Haller cell, Agger nasi cell, paradoxical middle turbinate, concha bullosa and the protrusion of the optic nerve. Conclusion: Limited CT can be used as a surgical roadmap for the cases with the anterior group of sinus involvement. It may be utilized for surgical planning of chronic CRS involving the anterior group of sinuses. For the posterior group of sinuses, it may not yield enough accuracy and the standard Full CT should be requested to prevent erroneous estimation.

Indirect carotid-cavernous sinus fistulas treated by transvenous approach through the superior ophthalmic vein: A case report and technical note.

Objective: To present the results of our treatment of indirect carotid- cavernous sinus fistulas with surgical exposure of the superior ophthalmic vein (SOV), retrograde venous catheterization, and coil embolization of the cavernous sinus in a patient whom the standard transvenous catherization for treatment of indirect carotid–cavernous fistulas had failed. Methods: No method Results: Complete fistula obliteration was accompanied by recovery of the clinical symptoms. Conclusion: The surgical SOV approach might be sufficient when standard endovascular intervention does not succeed. The technique is safe and effective when performed by an interdisciplinary team.

Cranial dural arteriovenous fistula: Predisposing factors to aggressive symptoms.

Objective: To evaluate the clinical and angiographic data of cranial dural arteriovenous fistula in Thai patients and to determine the predisposing factors to aggressive symptoms. Methods: Retrospective review of 71 patients with cranial dural arteriovenous fistula who underwent cerebral angiography at Siriraj Hospital between July 2002 – February 2006. Their clinical manifestations were classified as benign or aggressive symptoms. The relationship between aggressive symptoms and the following factors were studied: gender, location of the fistula, classification according to venous drainage pattern, presence of cerebral sinus thrombosis, and shunt multiplicity. Linear-by-linear association and chi-square test were used to determine statistical significance. Results: Sixteen (22.5%) of 71 patients with cranial dural arteriovenous fistula had aggressive presenting symptoms. Factors that significantly correlate with aggressive symptoms were location of the fistula, retrograde leptomeningeal venous drainage, presence of cerebral sinus thrombosis, and multiplicity. Factor which was not significantly correlated with aggressive symptoms was gender. Conclusion: This study evaluated clinical data and angiographic features of cranial dural arteriovenous fistula in Thai patients. Predisposing factors to aggressive symptoms were location of the fistula, retrograde leptomeningeal venous drainage, presence of cerebral sinus thrombosis, and multiplicity.

Paragangliomas of the head and neck: A retrospective review at Siriraj Hospital.

Objective: To analyze the distribution and radiological findings of paragangliomas of the head and neck region at Siriraj Hospital. Methods: The cases with pathological proven of paragangliomas in the head and neck from January 1996 to December 2003 at Siriraj Hospital were retrospectively reviewed. Clinical presentation and radiologic findings in term of location, size, number, pattern of enhancement, vascularity and bony destruction were analyzed. Results: There were 26 tumors among 22 patients which were 12 females and 10 males, with an average age of 47 years old. By locations, paragangliomas were found as carotid body tumor in 46.2%, glomus tympanicum in 11.5%, glomus vagale in 11.5%, glomus jugulare in 3.8%, glomus jugulotympanicum in 7.6% and rare locations in 19.2%. The unusual locations included sinonasal cavity, sphenoid sinus, supraglottic larynx, thyroid gland and posterior fossa. The presenting symptoms were neck mass in 53.8%, tinnitus in 26.9%, cranial nerve palsy in 19.2%, epistaxis in 3.8%, hoarseness of voice in 3.8%, severe headache in 3.8%. Multicentricity was found in 18%. Aggressive pattern was documented in 15.4 %. The radiological findings of paragangliomas in usual locations were all characteristic homogeneous intensely enhanacement or hypervascularity (100%). Those in rare locations had also central necrosis (60%). Bony destruction was shown in 9.5% of usual locations and 40% of unusual locations. No any of lesions in rare locations had multicentricity. Conclusion: Carotid body tumor is the most common paragangliomas in the head and neck region. Clinical presentation of a paraganglioma is related to location of the tumor. On the basis of the locations and radiographic characteristics, in common locations, imaging findings are characteristics and they may provide definite diagnosis, but in rare locations the radiological findings are not characteristics, and should be differentiating from other head and neck lesions.

Combined surgery and endovascular treatment of complicated traumatic carotid-cavernous fistulas: Results and illustrated cases.

Objective: To review Siriraj Hospital’s experiences with direct surgical treatment of complicated traumatic carotid-cavernous fistulas (CCFs) in the context of multidisciplinary approach. Methods: This study is a retrospective review of complicated direct carotid cavernous fistulas (CCFs) that had opened surgery after failure of detachable balloon embolization. Data were collected from medical records, radio-angiographic records, and follow-up results of combinations of treatment. Results: From 1993- April 2003, we have total 25 cases of combined surgery and endovascular treatment of traumatic carotid-cavernous fistulas (CCFs). Causes of unsuccessful balloon embolization are small-hole fistula, deflation of the balloon, difficult position of fistula, false aneurysm, risk of intracavernous internal carotid artery (ICA) occlusion, and tortuosity of ICA and draining veins. Various procedures were performed and all patients have good results with completed resolution of clinical triad symptoms. On follow-up cerebral angiography of 16 patients that received cavernous sinus packing, we could preserve the patency of ICA in 8 patients but 5 patients had thrombosis of ICA without ischemic events. In 3 patients, an operation to occlude the ICA was performed after failure of cavernus sinus packing. Conclusions: The standard treatment of carotid cavernous fistula is endovascular balloon embolization. When the endovascular treatment fails, surgical packing of cavernous sinus is immediately considered an alternative way to cure the CCFs and to offer additional technique to help increase the patency of ICA.

The limited protocol MRI in diagnosis of lumbar disc herniation.

OBJECTIVE: To assess agreement in detection of lumbar disc herniation (LDH) between limited and full protocol MRI. MATERIAL AND METHOD: 123 patients who requested lumbar MRI for diagnosis of disc herniation were assessed The full protocol MRI composed of sagittal T1-wi, sagittal T2-wi and axial T2-wi was performed on each patient. The sagittal T2-wi was selected as the limited protocol MRI. The limited and full protocols MRI of each patient were separately interpreted by three neuroradiologists to assess disc herniation and nerve root compression. The consensus results of limited and full protocol were compared. The diagnostic performance of each protocol was analyzed using surgery as the gold standard. RESULTS: There were 62 females and 61 males enrolled into the study between the age of 21-60 years old (means = 42.91 years). The duration of pain was 1-204 months (mean = 31.20 months). The degree of severity was mild in 23.58%, moderate 45.52% and severe 30.89% of cases. Thirty-three cases were operated on. For detection of LDH, the limited protocol gave the same interpretation results as the full protocol (0 = 1.04, 95%CI = 0.94, 1.14 with accepted range of 0.95-1.05). In nerve root compression, the limited protocol was not accurate as the full protocol (0 = 0.75, 95%CI = 0.87, 0.63). The sensitivity, specificity, accuracy, PPV, NPV, and LR+ in the surgical group of limited protocol in diagnosis of LDH were 82.61%, 80%, 81.82%, 90.48%, 60.67%, 4.13 and in nerve root compression were 54.84%, 100%, 57.58%, 100%, 12.5% respectively. The same statistics of full protocol MRI in diagnosis of LDH were 82.61%, 70.80%, 78.79%, 86.36%, 63.64%, 2.75 and of nerve root compression were 80.65%, 100%, 81.82%, 100%, 25% respectively. The sensitivity and specificity in diagnosis of LDH were not different in both protocols but the sensitivity of nerve root compression was statistically significant different (p < 0.013, 95%CI = -0.33, -0.25). CONCLUSION: The authors concluded that limited protocol MRI may replace full protocol MRI in diagnosis of LDH but not in nerve root compression.

Vascular loop compressing facial nerve in hemifacial spasm: demonstrated by 3D-phase contrast magnetic resonance angiography in 101 patients.

BACKGROUND: Vascular compression of the facial nerve is deemed to be the common cause of hemifacial spasm producing emphatic transmission. Although facial nucleus supersensitivity is more accepted as the main cause of hemifacial spasm. PURPOSE: To determine the vascular loop compression of the facial nerve in patients with hemifacial spasm by 3D-phase contrast (PC) magnatic resonance imaging (MRI). MATERIAL AND METHOD: A retrospective study of 101 patients with hemifacial spasm who went MRI and magnetic resonance angiography (MRA) of the brain was done. The magnitude images of the 3D-PC MRA was evaluated in axial and oblique coronal reconstruction planes blindly from symptomatic information. RESULTS: Among 101 patients, 53 affected the left side, 48 patients were right sided and none had bilateral involvement. Vascular loop compressing on the symptomatic side was found in 61 (60.4%) patients. For the asymptomatic side, there were 14 (13.86%) with vascular loop contact. Five patients (4.9%) had bilateral vascular compression. The proportion of vascular contact of the symptomatic and asymptomatic side was significantly different (with p < 0.001). The offending vessels were vertebral artery (32, 52.46%), posterior inferior cerebellar artery (7, 6.93%), anterior inferior cerebellar artery (6, 5.94%) and artery of uncertain origin (16, 26.23%). CONCLUSION: The study implied the usefulness of this simple technique to demonstrate the neurovascular contact of the facial nerve.

Giant cell tumor of the bone : Radiographic evaluation.

Giant cell tumor is a relatively common skeletal tumor with radiographically characteristic appearance in a predictable location. Clinical data from 66 patients with radiographical and from 37 patients with pathological diagnosis of giant cell tumor of the bone in Siriraj Hospital were retrospectively reviewed from June 1995 - December 2001. Histological grading was classified as grade I 78%, grade II 19%, and grade III 3%. Female patients accounted for a alight majority (F : M = 1.54 : 1). Eighty percent of the tumors were in the expected locations at the end of long bone (femur, tibia, radius, and humerus), where as a few lesions were located at atypical sites such as sacrum, talus, ulna, rib, or scapula. One patient had pulmonary metastasis and one patient had multifocal lesions. The aggressiveness of radiographic findings was evaluated and based on the following criterias : breaking of cortex, soft tissue involvement, joint involvement and large tumor size in correlation with histological grading and tumor recurrence. Our study showed no correlation between tumor size and histological grading.

The accuracy of magnetic resonance venography for diagnosis of dural sinus thrombosis.

A retrospective study of 24 patients who underwent magnetic resonance venography (MRV) was performed. The MRV was using a 3D-PC technique and thick-slab multiplanar reconstruction. Four patients underwent conventional angiography. There were 4 males and 20 females with an age range of 8-71 years. The MRV was considered as positive for dural sinus thrombosis (DST) in 8 patients and negative in 16 patients. There were 2 false positive in the MRV.The sensitivity of MRV is 100%,specificity 88%,positive predictive value 75% and negative predictive value 100%.We concluded that MRV is a valuable screening method for DST. One pitfall concerning the use of MRV is that a false positive interpretation may occur due to hypoplasia of the transverse sinus which is a normal variant.

Value of computed tomography in T-stage assessment and therapy of nasopharyngeal carcinoma.

The accurate evaluation of tumor size, localization and spread of nasopharyngeal carcinoma help optimal treatment planning. The purpose of our retrospective study is to compare the T-stage of nasopharyngeal carcinoma between evaluated by physical examination and CT scan and to compare the response to treatment in the group also underwent CT (147 patients) and the group without CT staging (40 patients). The sex ratio, and the mean age of the patients in both groups was not significantly different. Radiological study showed Stage 1 the tumor confined in nasopharyngeal region. Stage II showed tumor spreading with lateral extension to the parapharyngeal region. Stage III and stage IV, the tumor spread in a superior direction to the paranasal sinus and the base of the skull. CT staging resulted in upgrading the T stage in 88/147 cases ( 59.9%). A Complete response was higher in the CT than the non CT Group at the T2 and T4 stage. CT imaging is better than clinical examination and conventional imaging in detecting the involvement of more than one wall, base of skull involvement, differentiating tumor from sinusitis, detecting intracranial invasion and neck node involvement. In Conclusion, a CT scan is require in nasopharyngeal carcinoma patients for accurate staging, modified radiation treatment and improved treatment results.

Tc-99m stannous colloid-labeled leucocyte scintigraphy in the evaluation of brain abscess.

99mTc stannous colloid-labeled leukocyte scintigraphy was used to investigate brain abscesses in patients with underlying arteriovenous malformation or other brain abnormalities. 99mTc stannous colloid-labeled leukocytes are radiolabeled neutrophils and monocytes. The radiolabeled colloid is phagocytosed by the white cells. Six patients with underlying arteriovenous malformation (AVM) post embolisation with clinical diagnosis of brain abscess were studied. The 3 patients with positive 99mTc stannous colloid-labeled leukocyte scans were diagnosed as a cerebral abscess in all cases. One patient who had a negative 99mTc stannous colloid-labeled leukocyte scan did not have a brain abscess. Another with a negative scan had a pathologic diagnosis of chronic inflammation and foreign body reaction. The third with a negative scan was studied after treatment with antibiotic and debridement. In Summary 99mTc stannous colloid-labeled leukocyte scintigraphy is useful in conjungtion with CT scanning in investigating patients with brain abscess who have other underlying brain abnormality or who have an early brain abcess, or in the follow up of patients who have already received treatment in order to evaluate infection is still present and it is appropriate treatment.

Disseminated penicilliosis marneffei in immunocompetent hosts.

Two cases of disseminated Penicilliosis marneffei are reported; both were middle-aged female patients from the central part of Thailand who presented with multiple cystic skin lesion. Their systemic symptoms included chronic fever, weight loss, malaise, anemia, cervical lymphadenopathy and osteolytic bone lesions. They had no underlying disease causing immunosupression and both were HIV-negative. Skin manifestations occurred frequently in disseminated penicilliosis and abscesses were the most common manifestation in HIV-negative patients whereas umbillicated papules were common in HIV-positive ones. A biopsy from the skin lesions was good specimens for histopathological study and frequently yielded positive culture results. The characteristic histopathological feature is granulomatous inflammation with macrophages containing yeast-like organisms with septa which show a lack of budding. The characteristic mycologic feature of P.marneffei is a thermally dimorphic fungus which produces a mycelial phase colony appearing within 2 days at room temperature (25-30oC) and which produces a bright, purple-red, water-soluble pigment into the surrounding agar. The yeast form grows at 37oC as a whitish colony produced in 4 days and this produces less red pigment compared with the mycelial form. The first case was treated with oral itraconazole intermittently as a result of multiple recurrent episodes until she died of the disease after one year. The second case was treated with amphotercin B intravenously followed by oral itraconazole with a satisfactory result.

Nocardial brain abscesses.

Five cases of nocardial infection of central nervous system were reported. All patients were immunocompromised hosts due to corticosteroid and cytotoxic drugs therapy for underlying disease. Two cases showed disseminated infection. The imagings of brain abscess were presented.

Endovascular treatment of brain arteriovenous malformations in Siriraj Hospital.

Objective: To present our experience on endovascular embolization by using N-butyl cyanoacrylate and to demonstrate that this is an effective method in the treatment of brain arteriovenous malformations. Malerials and Methods: From 1992 to 1998, 92 patients with brain arteriovenous malformations who having had endovascular embolization as primary treatment was retrospectively reviewed. Results: 8 patients (8.7%) had completely cure by embolization alone wthout neurological complication. 17 patients (18.5%) were cured after combined treatment, 9 with surgical removal and the other 8 with radiosurgery. The neurological complications occurred in 17 patients (18.5%) with 3 deaths and vegetative stage. Conclusion: The endovascular embolization can cure the arteriovenous malformations that smaller than 3 cm, no matter what its location, and it is effective to reduce the nidus volume of the larger lisions, making them suitable for surgical resection or radiosurgery as to achieve te goal of complete eradication of the malformations.