Stapler versus conventional pharyngeal repair after total laryngectomy: a randomized clinical trial.

OBJECTIVES: The aim of the current study was to evaluate the functional outcomes of stapler pharyngeal closure after total laryngectomy by the incidence of PCT and assessment of swallowing after surgery. In addition, the study aimed to evaluate the oncological outcomes in terms of patients' survival rates. METHODS: This randomized clinical trial was conducted on 58 patients with advanced laryngeal carcinoma who underwent total laryngectomy. Patients were randomly assigned to two groups according to the method of pharyngeal repair after laryngectomy: manual closure group (n = 28), and stapler group (n = 30). Functional and oncological outcomes were assessed and compared. RESULTS: The incidence of pharyngocutaneous fistula was significantly less in the stapler group. Additionally, operative time was significantly shorter and swallowing function was better in the stapler group compared to the manual group. There was no statistically significant difference between groups regarding survival rates. CONCLUSION: The stapler is a reliable method for pharyngeal closure after total laryngectomy if the limits of its indications regarding the primary tumor are considered. Stapler closure decreases the incidence of PCF and decreases the surgical time. Good swallowing outcomes are achieved without compromising the oncological outcomes.

Tracheal resection anastomosis for rare tracheal inflammatory lesions mimicking malignancy: report of 2 cases.

BACKGROUND: Tumor-like lesions of the trachea are rare and challenging in diagnosis and management. Inflammatory myofibroblastoma, also known as Inflammatory pseudo tumors (IPTs), as well as Rosai Dorfman Disease (RDD) are inflammatory lesions that may involve the central airways with variable non-specific clinical features mimicking tumors. CASE PRESENTATION: In this study 2 cases with tumor-like lesions are presented. One case with an inflammatory pseudotumor and the other one with Rosai-Dorfman disease affecting the upper trachea. Both cases were successfully managed with tracheal resection anastomosis. CONCLUSION: Tracheal Inflammatory myofibroblastoma, and Rosai-Dorfman diseases are rare tumor like lesions that present with upper airway obstruction. Despite being benign, these lesions may have features suggestive of malignancy, requiring prompt management. Complete surgical excision by segmental resection and primary anastomosis (if feasible) is the treatment of choice with an optimum outcome.

Discrepancy between clinical and pathological staging of laryngeal carcinoma: a dilemma to be solved.

OBJECTIVES: The aim of this study was to investigate the degree of discrepancy between the clinical and pathological staging of laryngeal carcinoma, and the potential impact of this discrepancy on the outcomes and prognosis. METHODS: This study was conducted on 127 patients who underwent total laryngectomy over five years (October 2016-October 2021). Data collected from pretherapeutic clinical staging regarding the extent of the tumor affection of different laryngeal subsites was compared to the postsurgical pathological assessment. RESULTS: Overall, 12 out of 127 patients (9.4%) in the current study, were clinically over-staged from T3 to T4 due to radiological diagnosis of tumor infiltration of laryngeal cartilages that proved pathologically to be free of tumor. Additionally, discordance in the N stage was found in 12.6% (n = 16). However, stage discrepancy did not have a significant impact on the prognosis and survival. CONCLUSION: Discordance between clinical and pathological TNM staging of laryngeal carcinoma may affect the decision making and the choice of the treatment options. Some improvement can be probably achieved with advancements and higher accuracy of the preoperative diagnostic tools.

Management of frontal sinus fungal osteomyelitis in the COVID 19 era: A case series.

The aim of this study was to review different approaches and outcomes in the management of post-COVID-19 frontal sinus fungal osteomyelitis. The study included 19 patients with frontal sinus fungal osteomyelitis. The main line of treatment was surgical debridement (sequestrectomy). Approaches included combined external and endoscopic approaches (n = 15) and pure endoscopic approaches (n = 4) according to the extent and accessibility of the sequestrum. Postoperative healing was satisfactory in all patients. All patients returned to their normal daily activity within 4-6 weeks, without residual or recurrent frontal sinus infection, osteomyelitis or need for revision procedures. Within the limitation of this case series, it seems that there is no need to adopt a new therapy regimen for treatment of frontal sinus fungal osteomyelitis because the conventional and well-known treatment approach combining surgery and antifungal drugs seems to work well. However, early, and adequate debridement and sequestrectomy is crucial. Furthermore, an open approach may be required according to the extent of osteomyelitis.

Nasal Spine of the Frontal Bone: A Consistent Landmark for Safe Outside-In Frontal Drill-Out.

BACKGROUND: Outside-in frontal drill out entails drilling the frontal sinus floor in the midline before identifying and dissecting the frontal recesses. It is a more direct approach, especially in revision surgery or cases with challenging anatomy. OBJECTIVES: The aim of this study was to highlight the anatomical and surgical concepts for easy and safe outside-in frontal drill out by a preclinical anatomic study on cadaveric heads. In addition, to review our experience with this approach over a 5-year period for challenging frontal sinus pathologies. METHODS: The study included 2 sectors; a preclinical study, in which 5 cadaveric heads were dissected and studied to identify and standardize the anatomical landmarks of this approach. This was followed by a clinical case series which included 22 patients with challenging frontal sinus pathologies that were treated with this proposed approach. RESULTS: We concluded from the anatomic study that the nasal spine of the frontal bone (NSFB) and its anatomical orientation in relation to the nasal branch of the anterior ethmoidal artery (NBAEA) is a consistent landmark that enables the surgeon to identify the correct coronal trajectory of drilling to avoid injury of the cribriform and the skull base. The clinical case series included 22 patients that were successfully treated with the proposed approach. No intraoperative nor postoperative complications were reported in this study. Long-term follow-up showed that the frontal neo-ostium was patent in all cases (n = 22). CONCLUSION: Outside-in frontal drill-out is a safe and easy approach; especially in challenging frontal sinus pathologies; using the NSFB and its anatomical coronal orientation to the NBAEA as a consistent landmark, anterior to the skull base. This approach offers early, safe, and direct bone removal without the need for initial identification and dissection of the frontal recess.

Platelet-rich fibrin: an autologous biomaterial for healing assistance of pharyngeal repair in total laryngectomy.

OBJECTIVES: The aim of this study was to evaluate the potential role of platelet-rich fibrin (PRF) application on the pharyngeal repair on decreasing the incidence of pharyngocutaneous fistula (PCF) after total laryngectomy. METHODS: This randomized controlled clinical trial was conducted on 67 patients with advanced laryngeal carcinoma who underwent total laryngectomy, over 2 years in the Otorhinolaryngology Department, Mansoura University Hospitals, Egypt. Patients were randomly assigned into two groups: PRF group (n = 35) and control group (n = 32). Risk factors for development of PCF as well as the incidence of PCF were studied in both groups. RESULTS: There was no statistically significant difference between groups regarding demographic data, medical comorbidities, basal hemoglobin and albumin levels, data related to the tumor (location, grade and TNM staging) and surgical details (preoperative tracheotomy and neck dissection). However, regarding the incidence of PCF, there was a statistically significant difference between groups as shown in Table 2. PCF was detected in 2/35 patients (5.7%) in the PRF group and in 10/32 patients (31.3%) in the control group (p = 0.004). CONCLUSION: PRF application on the pharyngeal repair after total laryngectomy enhances the healing process and consequently decreases the incidence of PCF.

Surgiflo® may have a potential impact on the healing process in cricotracheal resection anastomosis.

OBJECTIVES: To evaluate the role of thrombin-based haemostatic agent Surgiflo® (Ethicon) in improving the outcome of cricotracheal resection anastomosis. DESIGN: Randomised controlled clinical trial. SETTING: Otorhinolaryngology Department, Mansoura University Hospitals, Egypt. PARTICIPANTS: This study included 55 patients with grade III and IV subglottic and/or cervical tracheal stenosis, who underwent cricotracheal resection anastomosis. Patients were randomly assigned into two groups: Surgiflo group (n = 20) and control group (n = 35). In Surgiflo patients, Surgiflo® was applied at the end of surgery over the whole operative field including the line of airway anastomosis with the purpose of adequate haemostasis and enhancing healing of the anastomosis. MAIN OUTCOME MEASURES: The success rate and the incidence of complications in both groups were compared. RESULTS: At the end of treatment, decannulation rate was 95% (19/20) in the Surgiflo groups and 82.8% (29/35) in the control group. The overall incidence of complications was significantly lower in the Surgiflo group (P = .021). Need for further surgical airway interventions in the form of repeated dilatation, granulation tissue removal or performing a tracheotomy was reported in 22.9% (8/35) of control group patients, in comparison with 5% (1/20) in Surgiflo group. CONCLUSION: Direct Surgiflo® application in the operative field enhances the anastomotic healing, decreases the incidence of anastomotic complications and subsequently improves the outcome. It can be recommended as an adjuvant to surgery in patients undergoing cricotracheal resection anastomosis.

Challenging tracheal resection anastomosis: Case series.

OBJECTIVES: This study was conducted to review our experience in Otorhinolaryngology Department, Mansoura University Hospitals, Egypt, in the last 2 years in the management of high-risk patients who underwent cricotracheal resection due to different pathologies. METHODS: This case series included nine patients with severe, grade III or IV subglottic / cervical tracheal stenosis. These patients were considered high risk patients due to unusual pathology / etiology of stenosis or associated surgical field morbidity. Four patients had recurrent stenosis after previous unsuccessful cricotracheal resection, three patients had subglottic stenosis due to external neck trauma which compromised the surgical field. One patient had upper tracheal neoplasm, and in 1 patient there was upper tracheal stenosis associated with tracheo-esophageal fistula. RESULTS: Successful decannulation was achieved in all patients (n = 9) without any reported major intraoperative or postoperative compilations. CONCLUSION: Cases of subglottic / upper tracheal stenosis due to uncommon pathologies like neoplastic lesions, external neck trauma compromising the surgical field and revision cricotracheal resection, can be successfully managed by cricotracheal resection. However, a highly skilled team, well familiar with these surgeries, is mandatory to achieve an optimum outcome.

Nasopharyngeal Angiofibroma Staging with a Novel Nominal Basis: An 18-Year Study in a Tertiary Center.

OBJECTIVE: To develop a systematic method for anatomic mapping of juvenile nasopharyngeal angiofibroma (JNA) tumors to standardize communication, facilitate surgical planning, and convey prognosis. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary referral center. SUBJECTS AND METHODS: Following Institutional Review Board approval, we performed a retrospective review of radiologic and angiographic data of patients with JNA presenting to the Department of Otolaryngology-Head and Neck Surgery, Mansoura University, from 2001 to 2017. All patients underwent angiography with embolization and had >1-year follow-up. Based on frequently involved anatomic sites and factors predictive of prognosis, the NSF-COR staging system (nose/nasopharynx, sinus, fossa-cranium, orbit, residual internal carotid artery supply) was developed to explicitly convey anatomic site of involvement and presence of residual vascularity. We validated the NSF-COR staging system against other systems with Pearson chi-square test based on risk factors and clinical outcomes of blood transfusion volume, recurrence, and JNA resectability. RESULTS: Fifty-four patients met inclusion criteria, where all primary cases (100%) demonstrated nose/nasopharynx involvement, followed by sinus (85.2%), natural fossae (85.2%), intracranial (26%), and orbital involvement (16.7%). These sites, with assessment of residual internal carotid artery vascular supply, were used to develop the NSF-COR anatomically based staging system. The components COR showed significant association with clinical outcomes of blood transfusion and recurrence. Contingency coefficients between the NSF-COR staging system and available staging systems showed significant correlations (P < .05) for prognosis. CONCLUSION: The NSF-COR staging system conveys a communicable anatomic map of JNA tumors that integrates residual vascularity of the tumor and demonstrates strong concordance with current staging systems to assess clinical outcomes.

Surgical management of suprastomal tracheal collapse in children.

OBJECTIVE: Suprastomal collapse is a complication of pediatric tracheotomy with a potential impact on decannulation success. The aim of this study was to review the experience in the management of pediatric suprastomal collapse in a tertiary-care center, detailing the surgical technique employed. METHODS: This study included 12 tracheotomised children with the diagnosis of suprastomal collapse in the last 5 years. All patients of the study underwent surgical intervention to manage suprastomal collapse to achieve tracheotomy decannulation. The surgical procedure entailed dissection of the pre-existing tracheotomy tract down to the trachea, then excision of the tract flush with the anterior tracheal wall. The tracheal opening was closed transversely with 3-4 interrupted absorbable sutures placed in craniocaudal direction. RESULTS: At the end of treatment all patients were decannulated successfully. No intraoperative complications were reported. Minor postoperative complications were reported in 3 children in the form of mild surgical emphysema (n = 2) and wound infection (n = 1). Those patients were successfully managed conservatively. CONCLUSION: This technique is a simple and effective procedure enabling immediate decannulation with very low morbidity. In a long term follow up period, no recurrence has been reported and all patients returned to their usual quality of life.

Neurovascular Surgical Keys Related to Sphenoid Window: Radiologic Study of Egyptian's Sphenoid.

OBJECTIVES: The anatomic variations of the sphenoid sinus and its relation to the surrounding neurovascular structures are a subject of interest. The purpose of this study was to radiologically assess the frequency of protrusion/dehiscence of key neurovascular landmarks surrounding the Egyptians' sphenoid. METHODS: This is a cross-sectional descriptive study of sinonasal computed tomography of the sphenoid sinus in 500 adult Egyptians, conducted at Mansoura University Hospitals; Egypt, over a period of 1 year. Two archives were used for collecting the data; the hard archive and the electronic archive. Variables of interest included the extent of sphenoid sinus pneumatization; intersphenoid septation pattern; protrusion/dehiscence of the internal carotid artery, optic nerve, maxillary nerve, and vidian nerve; and detection of the Onodi cell. RESULTS: Population of this study included 265 women and 235 men. Their ages ranged from 18-68 years. The bilateral sellar-type pneumatization was shown as the most common pneumatization type (96.8%). Pneumatizations of the pterygoid process, anterior clinoid process, and greater wing of the sphenoid were identified in 9.3%, 8.9%, and 31.8% consequently. A single intersphenoid septum was detected in 85.2%, whereas multiple intersphenoid septums were noted in 11.6%. Protrusion of the internal carotid artery, optic nerve, vidian nerve, and maxillary nerve was recorded in 8.5%, 9.1%, 6.6%, and 3.4% consequently, while dehiscence was reported in 7.2%, 15%, 11.9%, and 4.2% consequently as well. Onodi cell was recognized in 18%. CONCLUSIONS: This radiologic study highlights significant variations of surgically important anatomic structures related to the sphenoid sinus in Egyptians.

Partial cricotracheal resection for severe upper tracheal stenosis: Potential impacts on the outcome.

OBJECTIVE: The aim of this study was to investigate the potential impact of multiple preoperative and intraoperative variables on the outcome of partial cricotracheal resection and tracheal resection anastomosis (PCTR/TRA). METHODS: The study was conducted on 35 consecutive patients of grade III and IV upper tracheal stenosis with or without subglottic involvement. The indication of PCTR/TRA was post intubation stenosis in all patients. Overall complications (major and minor) occurred in 18 patients. Perioperative mortality occurred in 1 patient. Anastomotic complications do not always mean failure of surgery. They may indicate one or more interventions; such as removal of granulation tissue or dilatation of restenosis, with good results in most cases. RESULTS: At the end of treatment, 30 (85.7%) patients were decannulated successfully with effortless breathing and with good phonation and swallowing. Several perioperative factors were found to have a significant impact on the outcome of PCTR/TRA. Of these factors, comorbidities had the most significant negative impact, and indeed all the three patients who had comorbidities, were not successfully decannulated. Duration of intubation, length of resected segment and previous open airway interventions was reported to have a significant negative impact on the outcome of surgery. CONCLUSION: PCTR/TRA for treatment of post traumatic subglottic or upper tracheal stenosis has a high success rate, especially in healthy patients without comorbidities, and without previous open airway interventions.

Surgical correction of bifid nose.

OBJECTIVES: Evaluation of the aesthetic outcome and functional aspect after surgical correction of bifid nose by combined Millard forked flap with external rhinoplasty BACKGROUND: Bifid nose is a rare congenital anomaly that results during facial development but the explicit mechanism is not clearly understood. Clinical findings are quite variable with a wide range of severity. Surgical correction still represents great challenge to facial plastic surgeons; extensive deformities in many cases, rarity of condition and paucity of publications are contributing factors. METHODS: Surgical correction of six patients with bifid nose by a combined Millard forked flap with external rhinoplasty RESULTS: The aesthetic and functional outcomes were acceptable for all patients and parents. There were no considerable postoperative complications. CONCLUSIONS: This approach is highly effective for various grades of bifid nose. Early management is preferable to avoid psychological morbidity. Secondary rhinoplasty is usually needed for cosmetic refinement.

Midline nasofrontal dermoids in children: A review of 29 cases managed at Mansoura University Hospitals.

OBJECTIVES: Nasal dermoids are congenital anomalies constituting 3.7-12.6% of dermoids in the head and neck. Most of lesions are superficial but there is always a risk that it may end blindly within the deep structures of the nose or extend intracranially. Complete excision, regardless of extension, is essential and must be balanced against cosmoses. This study reviews the clinical characteristics and imaging findings as well as the appropriate surgical approach adopted for 29 cases managed at Mansoura University Hospitals. METHODS: A retrospective analysis was performed in 29 patients admitted for management of nasal dermoid between Jan 2001 and Jan 2015 at the Otolaryngology department of our tertiary referral university hospital. Recorded data included patient's demographics, complaint, lesion's site, pre-operative radiological findings, surgical technique, intra-operative findings, and post-operative squeal. RESULTS: This series included 12 (41%) female and 17 (59%) male children, with a mean age of 2.5 years. Twenty seven children presented with a nasofrontal swelling of which 20 had an apparent sinus. Other presentations included a swelling in the inner canthum (1), nasal tip and columella (1). Nine (31%) patients had a history of infection and two patients gave a positive history of meningitis. Intracranial extradural extension was identified in 10 patients (34.5%) during preoperative imaging. Surgical modalities included local excision and direct closure (12), open rhinoplasty (7), bicoronal excision and craniotomy (10). In 9 cases, the tract was adherent to the dura but was carefully dissected and in one case resection required excision of a segment of dura and reconstruction. In a follow up period of 1-8 years, recurrence was detected in one case and the cosmetic results were satisfactory. CONCLUSIONS: Those lesions are rare and require early precise surgical planning to achieve complete en bloc excision. This study reports a low morbidity associated with management of nasal dermoids with intracranial extension.

Date of birth and hay fever risk in children and adolescents of Kazakhstan.

UNLABELLED: Introduction the first months of life are the most vulnerable period in allergic disease development and it is not clear enough whether inhalant pollen allergen exposure predisposes the risk of consequent allergic reactions. OBJECTIVE: To study the clinical and epidemiological criteria of hay fever with special emphasis on investigation of the relationship between the date of birth and seasonal allergic rhinitis development in children and adolescents in Kazakhstan. METHODS: The prospective hospital based study was conducted during pollen season from the beginning of May to the end of October in two consequent years 2010 and 2011. 184 children and adolescents at the age of 1--17 years underwent consultations and skin prick tests in the allergological center "Umit" (Astana, Kazakhstan). Special allergological questionnaires were developed and adapted for local residents. The assessment of symptoms severity was performed using a scoring system. Skin prick tests were performed in 112 patients. The number of patients was explained by the age limitations. Correlation analysis between skin prick test results and the month of birth were performed. RESULTS: It was found that in summer months there were the highest number of patients with seasonal allergic rhinitis 68 (36.9%), followed by spring 44 (23.9%), then autumn 37 (20.1%) and the lowest percent of patients 35 (19.1%) was born in winter. Rhinoconjunctival syndrome was diagnosed in 180 (97.8%) patients, pollen induced bronchial asthma in 76 (41.3%) and pollen induced urticaria in 35 (19.0%) patients. Mono sensitization among Kazakhstan children and adolescents was determined only to several species of the plants, mainly to Artemisia Absinthium (68.2%) and Sunflower (25.7%), whereas multiple sensitization to the mix of weeds was determined in 75 (66.9%) patients, to the mix of meadow grass in 33 (29.4%), mix of meadow grass+mix of weeds in 25 (22.3%) and mix of trees in 9 (7.1%) patients. The mean of symptoms severity of total scoring (24) was 15.5. The mean of IgE level in blood tests was 323.2IU/ml. CONCLUSIONS: Our results proved that first months of life are the crucial period and inhalant pollen allergen exposure, particularly to the weeds pollen, predisposes the risk of consequent allergic reactions development in children and adolescents in Kazakhstan. This fact may predetermine the risk of consequent allergic reactions development and the awareness of patients about it helps to prevent following severe clinical manifestations.

Urgent maxillectomy in infants for rare infantile maxillary tumors.

OBJECTIVE: The purpose of this study was to present our experience with definitive surgical management of infants with Melanotic neuroectodermal tumor of infant (MNTI) and epithelioid hemangioendothelioma (EHE). PATIENTS AND METHODS: This study included four male infants with histologically proven MNTI (three infants) and EHE (one infant). CT scan and MRI were for taken for the patients preoperatively. Surgical intervention was used in all infants. RESULTS: This study is a retrospective study that reflects our experience in the last 20 years in maxillectomy in infants. All infants were male with mean age 6 months (2-9 months). Complete resection of the tumor was achieved all infants with no residual or recurrence. Neither chemotherapy nor radiation was used in this study. CONCLUSIONS: MNTI and EHE are rare tumor of infant. They present as a slow painless hard swelling of the maxilla. Imaging is an essential before surgical treatment. Complete excision is curative.

Juvenile nasopharyngeal angiofibroma with intracranial extension: analysis of 23 Egyptian patients.

The purpose of this study was to present our experience with definitive surgical management of patients with Juvenile nasopharyngeal angiofibroma with intracranial extension. The study included 23 male adolescents with histologically proven juvenile nasopharyngeal angiofibroma. The mean age was 14.7 years (12-20 years). CT, MRI+/-angiographies were for taken for the patients. Preoperative embolization was done with gel foam before the operation. Two surgical procedures were used; anterior subcranial transfacial transmaxillary approach (21 patients), while craniofacial resection was used in two patients. Middle cranial fossa was affected in 22 patients while anterior cranial fossa was affected in only one patient. Complete resection of the tumor was achieved in 19 patients with residual or recurrence in four patients. Complications of the surgical approaches were reported in 14 patients. The subcranial transfacial transmaxillary approach avoids the complications of craniotomy and provides adequate access for excision of Juvenile nasopharyngeal angiofibroma with intracranial extradural extension.

Cervical sympathetic schwannoma with postoperative first bite syndrome.

Extracranial schwannomas occurring in the head and neck region may arise from cranial, peripheral or autonomic nerves. Determination of the nerve of origin is not often made until the time of surgery. Schwannomas arising from the cervical sympathetic chain are extremely rare. These interesting tumors along with schwannomas in general and the remaining class of neurogenic tumors are known for their ability to mimic the physical and radiological findings of carotid body tumors. Surgery is the treatment of choice and major complications are infrequent. However, we report a case of cervical sympathetic chain schwannoma with postoperative first bite syndrome.

Role of diffusion-weighted MR imaging in cervical lymphadenopathy.

The role of diffusion-weighted magnetic resonance imaging (MRI) for differentiation between various causes of cervical lymphadenopathy was evaluated. In a prospective study, 31 untreated patients (22 males and nine females, aged 5-70 years) with 87 cervical lymph nodes underwent diffusion-weighted MRI before performance of neck dissection (n=14), surgical biopsy (n=9) or core biopsy (n=8). Diffusion-weighted MR images were acquired with a b factor of 0 and 1,000 s/mm2 using single-shot echo-planar sequence. Apparent diffusion coefficient (ADC) maps were reconstructed for all patients. The signal intensity of the lymph nodes was assessed on images obtained at b=0 or 1,000 s/mm2 and from the ADC maps. The ADC value of lymph nodes was also calculated. On the ADC map, malignant nodes showed either low (n=52) or mixed (n=20) signal intensity and benign nodes revealed high (n=13) or low (n=2) signal intensity. The mean ADC value of metastatic (1.09+/-0.11x10(-3) mm2/s) and lymphomatous (0.97+/-0.27x10(-3) mm2/s) lymph nodes was significantly lower than that of benign (1.64+/-0.16x10(-3) mm2/s) cervical lymph nodes (P<0.04). When an ADC value of 1.38x10(-3) mm2/s was used as a threshold value for differentiating malignant from benign lymph nodes, the best results were obtained with an accuracy of 96%, sensitivity of 98%, specificity of 88%, positive predictive value of 98.5% and negative predictive value of 83.7%. The smallest detected lymph node was 0.9 cm. In conclusion, diffusion-weighted MRI with ADC mapping is a new promising technique that can differentiate malignant from benign lymph nodes and delineate the solid viable part of the lymph node for biopsy. This technique provides additional useful physiological and functional information regarding characterization of cervical lymph nodes.