BACKGROUND Lymphangiomas are a group of benign swellings which are commonly seen in children.The most common sites of presentation is the head and neck region,less commonly seen in axilla,chest,liver,spleen,etc.The id...BACKGROUND Lymphangiomas are a group of benign swellings which are commonly seen in children.The most common sites of presentation is the head and neck region,less commonly seen in axilla,chest,liver,spleen,etc.The ideal modality of treatment has always been surgical excision irrespective of the site and age group.But with the advent of minimally invasive surgical techniques,it is now possible to perform excision of parapharyngeal space lesions with minimal morbidity and good clearance.CASE SUMMARY A 42-year-old male patient who presented with difficulty in swallowing and had undergone surgery twice outside,where Transcervical approach was attempted to remove the parapharyngeal mass,but failed.Magnetic resonance imaging scan demonstrated a 6 cm x 5 cm x 4 cm left parapharyngeal mass.He underwent transoral robotic surgery for the excision of the parapharyngeal lesion and had an uneventful post-operative recovery.CONCLUSION Lymphangiomas are hamartomatous swellings which are benign in nature.The symptoms of the patient with large parapharyngeal mass include dysphagia,dyspnoea and neck swelling.Clinicoradiological evaluation is of utmost importance to determine the adjacent vital structures and the approach to the tumor.With the advent of robotics in oncology,transoral robotic excision is one of the best approaches to perform such a surgery.展开更多
Background and Objective: The primary submucous type of nasopharyngeal carcinoma (NPC) or the recurrent NPC in the parapharyngeal space is difficult to be diagnosed histologically by conventional biopsy because of the...Background and Objective: The primary submucous type of nasopharyngeal carcinoma (NPC) or the recurrent NPC in the parapharyngeal space is difficult to be diagnosed histologically by conventional biopsy because of the obstruction of the surrounding structures. This study was performed to evaluate the needle biopsy approach through the madibular area into the parapharyngeal space under the guidance of computed tomography (CT) for NPC. Methods: Between July 6, 2005 and October 23, 2009, a total of 6 patients were enrolled into the study. Two patients with cervical lymph node metastasis were clinically suspicious of NPC according to their clinical manifestations. However, no cancer cell could be found by repeated nasopharyngeal biopsies followed by histologic examinations. The other 4 patients were diagnosed with recurrent NPCs by magnetic resonance imaging (MRI) or/and positron emission tomography (PET)-CT scan, showing tumors in the parapharyngeal spaces in 3 patients and enlarged retropharyngeal lymph node in 1 patient. The CT-guided puncture was performed through the mandibular skin and the cutting needle biopsy was taken at the parapharyngeal space focus. Results: All the cutting needle biopsies of projected locations have been performed safely. Finally, all the 7 specimens met the requirement of pathologic diagnosis and the cases were all confirmed histologically to be NPCs. The main complication was mild ache at the puncture point. No blood vessel or nerve was injured and no patient needed special treatment. Conclusions: The CT-guided puncture biopsy of the parapharyngeal space through the mandibular area is simple and feasible. It can be an additional option for routine nasopharyngeal biopsy.展开更多
The parapharyngeal space(PPS) is an inverted pyramid-shaped deep space in the head and neck region, and a variety of tumors, such as salivary gland tumors, neurogenic tumors, nasopharyngeal carcinomas with parapharyng...The parapharyngeal space(PPS) is an inverted pyramid-shaped deep space in the head and neck region, and a variety of tumors, such as salivary gland tumors, neurogenic tumors, nasopharyngeal carcinomas with parapharyngeal invasion, and lymphomas, can be found in this space. The differential diagnosis of PPS tumors remains challenging for radiologists. This study aimed to develop and test a modified method for locating PPS tumors on magnetic resonance(MR) images to improve preoperative differential diagnosis. The new protocol divided the PPS into three compartments: a prestyloid compartment, the carotid sheath, and the areas outside the carotid sheath. PPS tumors were located in these compartments according to the displacements of the tensor veli palatini muscle and the styloid process, with or without blood vessel separations and medial pterygoid invasion. This protocol, as well as a more conventional protocol that is based on displacements of the internal carotid artery(ICA), was used to assess MR images captured from a series of 58 PPS tumors. The consequent distributions of PPS tumor locations determined by both methods were compared. Of all 58 tumors, our new method determined that 57 could be assigned to precise PPS compartments. Nearly all(13/14; 93%) tumors that were located in the pre-styloid compartment were salivary gland tumors. All 15 tumors within the carotid sheath were neurogenic tumors. The vast majority(18/20; 90%) of trans-spatial lesions were malignancies. However, according to the ICA-based method, 28 tumors were located in the pre-styloid compartment, and 24 were located in the post-styloid compartment, leaving 6 tumors that were difficult to locate. Lesions located in both the pre-styloid and the post-styloid compartments comprised various types of tumors. Compared with the conventional ICA-based method, our new method can help radiologists to narrow the differential diagnosis of PPS tumors to specific compartments.展开更多
Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy...Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy. The results showed that involvement of parapharyngeal space was very common in NPC, about 80% (160/200 cases) ; particularly unilateral or bilateral retro-styloid spaces, about 69.5% (139/200 cases). It was proposed that patients with NPC had a high Incidence of ipsilateral cervical node metastasis. Contralateral cervical node metastasis was rare. The development of cervical node metastasto in NPC has two modes: one Is direct Infiltration of the retro-stylold space by the lesion; the other Is along the nasopharyngeal lymphatic rete. The data also showed that patients with NPC who presented symptoms of Ⅸ- Ⅲ cranial nerve paralyses always had ipsilateral or bilateral retro- styloid space Infiltrations.展开更多
BACKGROUND Solitary fibrous tumors(SFTs)occurring in the parapharyngeal space are rare,and their final diagnosis depends on pathological and immunohistochemical analyses.Once the tumor is diagnosed,complete resection ...BACKGROUND Solitary fibrous tumors(SFTs)occurring in the parapharyngeal space are rare,and their final diagnosis depends on pathological and immunohistochemical analyses.Once the tumor is diagnosed,complete resection and regular postoperative follow-up are required.CASE SUMMARY A 40-year-old male patient with a right parotid gland mass discovered 8 years ago was admitted to hospital.The mass showed no tenderness or local skin redness.Imaging was carried out as the patient had stable vital signs and showed that the mass was a dumbbell-shaped tumor comprising a superficial tumor approximately 5 cm long and 3 cm wide in size that compressed the right parotid gland and a deep tumor located in the right parapharyngeal space approximately 4.5 cm long and 2.5 cm wide in size.Both tumors were connected in the middle.Prior to surgery,the tumors were considered to be parapharyngeal schwannomas.During surgical dissection,the tumors were found to be smooth and tough,without obvious adhesion to the surrounding tissues.The tumors were revealed to be a SFT following postoperative pathological analysis.CONCLUSION SFTs in the parapharyngeal space are rarely reported,and complete resection of such tumor is recommended.Adjuvant chemoradiotherapy is used in patients with extensive tumor invasion to lower the recurrence rate.Postoperative longterm follow-up is required.展开更多
Extra-nasopharyngeal lymphoepithelioma-like carcinomas (LELC) are uncommon epithelial tumors. A few isolated case reports and series are available in literature involving the larynx, pharynx, salivary gland, lung etc....Extra-nasopharyngeal lymphoepithelioma-like carcinomas (LELC) are uncommon epithelial tumors. A few isolated case reports and series are available in literature involving the larynx, pharynx, salivary gland, lung etc., but involvement in the parapharyngeal space has not yet been reported. We aim to highlight one such case that has a clinical and radiological characteristic of a benign lesion whilst the histopathology reveals an infiltrating neoplasm. The typical clinical aggressiveness of a classical LELC of extra-nasopharyngeal lesion as described in literature is not present in our case. Also seen is an uncommon finding of abnormal branching of left external carotid artery. There is no standard treatment protocol for such a tumor;however, wide excision of this tumor in the parapharyngeal space via trans-cervical, trans-mandibular, trans-palatal approach has shown good and satisfactory tumor control of the primary site so far.展开更多
Most of the parapharyngeal space tumours are benign.The primary treatment is complete resection of the tumour.Due to its location in the deep neck space,a pre-styloid tumour can be resected via the transoral approach....Most of the parapharyngeal space tumours are benign.The primary treatment is complete resection of the tumour.Due to its location in the deep neck space,a pre-styloid tumour can be resected via the transoral approach.However,the surgical field is limited by the small oral cavity.With the use of rigid endoscopes,removing benign tumours through transoral approach in the parapharyngeal space is possible as they provide a broad and enlarged view of the confined space.Here,we report a case of a 64-year-old male with a giant pre-styloid parapharyngeal space tumour,who successfully underwent transoral endoscopic excision.Postoperatively,the patient had short hospital stay of total 3 days.His chewing and swallowing were not affected,and he resumed oral feeding prior to discharge.展开更多
Synovial sarcoma is a rare soft tissue sarcoma of the head and neck region involving the parapharyngeal space.The diagnosis of synovial sarcoma can be very challenging to the pathologists.We present a rare case of par...Synovial sarcoma is a rare soft tissue sarcoma of the head and neck region involving the parapharyngeal space.The diagnosis of synovial sarcoma can be very challenging to the pathologists.We present a rare case of parapharyngeal synovial sarcoma in a young female patient who had a two-month history of left cervical intumescent mass at level II.The fine needle aspiration cytology of the mass was proved inconclusive.Transcervical excision of the mass was performed and the first case of parapharyngeal sarcoma was identified in our center by fluorescence in situ hybridization(FISH) technique.Repeat imaging revealed residual tumor.The patient successfully underwent a second excision of the residual tumor and received adjuvant radiotherapy.展开更多
Background:Several approaches have been described for the excision of parapharyngeal space tumors(PPSTs).Advances in endoscopy gave a further stimulus to the use of the transoral route.Aims:We present our experience w...Background:Several approaches have been described for the excision of parapharyngeal space tumors(PPSTs).Advances in endoscopy gave a further stimulus to the use of the transoral route.Aims:We present our experience with the endoscopy-assisted transoral approach(EATA)in this regard and a review of the most recent literature about EATA for PPSTs excision.Materials and Methods:We retrospectively analyzed our experience and systematically reviewed the literature about the outcomes of this technique.Results:Seven PPSTs were completely excised,with three of them requiring a combined transcervical approach.Only one case of postoperative wound dehiscence was registered,and the mean length of stay was 3.9 days.Final histopathological examination confirmed the results obtained with preoperative fine-needle aspiration biopsy in all cases and no recurrences were apparent after a mean follow-up of 28.1 months.Discussion:Magnetic resonance imaging,the modified Mallampati score and the 8 Ts criteria are useful instruments for the choice of the most appropriate surgical approach.Conclusion:In light of our experience and following other published series in the literature,we believe that EATA may represent a safe and effective approach for the treatment of the majority of PPSTs.展开更多
Surge pressure caused by pipe moving through the wellbore full of drilling .fluid is the main factor affecting wellbore stability, on which the additional mud density isdesigned. Thus if is desired to predict the surg...Surge pressure caused by pipe moving through the wellbore full of drilling .fluid is the main factor affecting wellbore stability, on which the additional mud density isdesigned. Thus if is desired to predict the surge pressure with high accuracy. While this is closely, related with the selection of mud rheological models. Yield-Pseudoplastic model which has three parameters and is.famous for its higher accuracy has been used to describe the mud rheological properties in recent years. Based on this model the paper presents a new theoretical model for calculating surge pressure caused by mud viscosity during tripping or casing in a concentric annulus of directional wells under steady laminar situation. For convenience, the paper plots the distribution of the coefficients of surge pressure for different conditions. An example is given. These results provide the basis for controlling pressure surges and tripping velocity.展开更多
The coexistence of acquired hemophilia A with a secondary retropharyngeal hematoma is an extremely unusual condition with important clinical implications. The purpose of this paper is to present a case involving a pat...The coexistence of acquired hemophilia A with a secondary retropharyngeal hematoma is an extremely unusual condition with important clinical implications. The purpose of this paper is to present a case involving a patient whose first clinical manifestation, namely dysphagia, along with specific clinical examination and imaging findings, led to an incorrect initial diagnosis of a retropharyngeal abscess. However, performance of a more thorough clinical examination led to the correct diagnosis of a hematoma secondary to acquired hemophilia A. This allowed surgery to be avoided in a patient at a high risk of bleeding. Conclusions: Acute neck masses require meticulous differential diagnosis assessing the possible presence of various causative systemic diseases before the most appropriate therapy can be determined.展开更多
Objective:Parapharyngeal space contains intricate vascular anatomy(external and internal carotid arteries)that might be inadvertently injured during the dissection in this plane.None of the bony landmarks can be used ...Objective:Parapharyngeal space contains intricate vascular anatomy(external and internal carotid arteries)that might be inadvertently injured during the dissection in this plane.None of the bony landmarks can be used during the transoral robotic surgery(TORS)radical tonsillectomy as these landmarks lie lateral to the internal carotid artery(ICA)and external carotid artery(ECA)in transoral approach.Our study aims to identify the safe surgical limits during the dissection of parapharyneal space in TORS radical tonsillectomy and to correlate the same with radiological study.Material and methods:Fifteen cadavers(30 head and neck regions)and 50 CT-Angiogram of neck(100 head and neck regions)were included in the anatomical and radiological study respectively.The vertical midpoint of anterior tonsillar pillar(palatoglossus muscle)was taken as the reference point and all the measurements were done at the level of reference point both for anatomical and radiological study.Distance between tonsillar fossa and ECA,distance between tonsillar fossa and ICA,relation between ECA and styloglossus and relation between ICA and stylopharyngeus at reference level were studied.Results:The mean distance of ECA from the tonsillar fossa at the reference point was 18.2 mm in the anatomical study and 16.2 mm in the radiological study.The mean distance of ICA from the tonsillar fossa was 23.4 mm and 23.3 mm in the anatomical study and radiological study.There was no significant difference between the anatomical and radiological findings for both the mean distance between ECA and ICA to the tonsillar fossa(p value was 0.45 and 0.30 respectively).ECA was located posterolateral to styloglossus in 24 cases(80.0%)and 79 cases(79.0%)in the anatomical and radiological study respectively.ICA was found posterolateral to stylopharyngeus in 21 cases(70.0%)and 69 cases(69.0%)in the anatomical and radiological study respectively.Conclusion:The muscular plane between styloglossus and stylopharyngeus can be used as an envelope to locate the ECA and ICA that lie medial to these critical vascular structures during TORS.We propose to divide the parapharyngeal space into two compartments(anterior and posterior)based on the surgical perspective of inside-out anatomy.The anterior compartment houses styloglossus muscle with ECA posterolateral to it and the posterior compartment has stylopharyngeus and ICA posterolateral to it.展开更多
文摘BACKGROUND Lymphangiomas are a group of benign swellings which are commonly seen in children.The most common sites of presentation is the head and neck region,less commonly seen in axilla,chest,liver,spleen,etc.The ideal modality of treatment has always been surgical excision irrespective of the site and age group.But with the advent of minimally invasive surgical techniques,it is now possible to perform excision of parapharyngeal space lesions with minimal morbidity and good clearance.CASE SUMMARY A 42-year-old male patient who presented with difficulty in swallowing and had undergone surgery twice outside,where Transcervical approach was attempted to remove the parapharyngeal mass,but failed.Magnetic resonance imaging scan demonstrated a 6 cm x 5 cm x 4 cm left parapharyngeal mass.He underwent transoral robotic surgery for the excision of the parapharyngeal lesion and had an uneventful post-operative recovery.CONCLUSION Lymphangiomas are hamartomatous swellings which are benign in nature.The symptoms of the patient with large parapharyngeal mass include dysphagia,dyspnoea and neck swelling.Clinicoradiological evaluation is of utmost importance to determine the adjacent vital structures and the approach to the tumor.With the advent of robotics in oncology,transoral robotic excision is one of the best approaches to perform such a surgery.
文摘Background and Objective: The primary submucous type of nasopharyngeal carcinoma (NPC) or the recurrent NPC in the parapharyngeal space is difficult to be diagnosed histologically by conventional biopsy because of the obstruction of the surrounding structures. This study was performed to evaluate the needle biopsy approach through the madibular area into the parapharyngeal space under the guidance of computed tomography (CT) for NPC. Methods: Between July 6, 2005 and October 23, 2009, a total of 6 patients were enrolled into the study. Two patients with cervical lymph node metastasis were clinically suspicious of NPC according to their clinical manifestations. However, no cancer cell could be found by repeated nasopharyngeal biopsies followed by histologic examinations. The other 4 patients were diagnosed with recurrent NPCs by magnetic resonance imaging (MRI) or/and positron emission tomography (PET)-CT scan, showing tumors in the parapharyngeal spaces in 3 patients and enlarged retropharyngeal lymph node in 1 patient. The CT-guided puncture was performed through the mandibular skin and the cutting needle biopsy was taken at the parapharyngeal space focus. Results: All the cutting needle biopsies of projected locations have been performed safely. Finally, all the 7 specimens met the requirement of pathologic diagnosis and the cases were all confirmed histologically to be NPCs. The main complication was mild ache at the puncture point. No blood vessel or nerve was injured and no patient needed special treatment. Conclusions: The CT-guided puncture biopsy of the parapharyngeal space through the mandibular area is simple and feasible. It can be an additional option for routine nasopharyngeal biopsy.
文摘The parapharyngeal space(PPS) is an inverted pyramid-shaped deep space in the head and neck region, and a variety of tumors, such as salivary gland tumors, neurogenic tumors, nasopharyngeal carcinomas with parapharyngeal invasion, and lymphomas, can be found in this space. The differential diagnosis of PPS tumors remains challenging for radiologists. This study aimed to develop and test a modified method for locating PPS tumors on magnetic resonance(MR) images to improve preoperative differential diagnosis. The new protocol divided the PPS into three compartments: a prestyloid compartment, the carotid sheath, and the areas outside the carotid sheath. PPS tumors were located in these compartments according to the displacements of the tensor veli palatini muscle and the styloid process, with or without blood vessel separations and medial pterygoid invasion. This protocol, as well as a more conventional protocol that is based on displacements of the internal carotid artery(ICA), was used to assess MR images captured from a series of 58 PPS tumors. The consequent distributions of PPS tumor locations determined by both methods were compared. Of all 58 tumors, our new method determined that 57 could be assigned to precise PPS compartments. Nearly all(13/14; 93%) tumors that were located in the pre-styloid compartment were salivary gland tumors. All 15 tumors within the carotid sheath were neurogenic tumors. The vast majority(18/20; 90%) of trans-spatial lesions were malignancies. However, according to the ICA-based method, 28 tumors were located in the pre-styloid compartment, and 24 were located in the post-styloid compartment, leaving 6 tumors that were difficult to locate. Lesions located in both the pre-styloid and the post-styloid compartments comprised various types of tumors. Compared with the conventional ICA-based method, our new method can help radiologists to narrow the differential diagnosis of PPS tumors to specific compartments.
文摘Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy. The results showed that involvement of parapharyngeal space was very common in NPC, about 80% (160/200 cases) ; particularly unilateral or bilateral retro-styloid spaces, about 69.5% (139/200 cases). It was proposed that patients with NPC had a high Incidence of ipsilateral cervical node metastasis. Contralateral cervical node metastasis was rare. The development of cervical node metastasto in NPC has two modes: one Is direct Infiltration of the retro-stylold space by the lesion; the other Is along the nasopharyngeal lymphatic rete. The data also showed that patients with NPC who presented symptoms of Ⅸ- Ⅲ cranial nerve paralyses always had ipsilateral or bilateral retro- styloid space Infiltrations.
文摘BACKGROUND Solitary fibrous tumors(SFTs)occurring in the parapharyngeal space are rare,and their final diagnosis depends on pathological and immunohistochemical analyses.Once the tumor is diagnosed,complete resection and regular postoperative follow-up are required.CASE SUMMARY A 40-year-old male patient with a right parotid gland mass discovered 8 years ago was admitted to hospital.The mass showed no tenderness or local skin redness.Imaging was carried out as the patient had stable vital signs and showed that the mass was a dumbbell-shaped tumor comprising a superficial tumor approximately 5 cm long and 3 cm wide in size that compressed the right parotid gland and a deep tumor located in the right parapharyngeal space approximately 4.5 cm long and 2.5 cm wide in size.Both tumors were connected in the middle.Prior to surgery,the tumors were considered to be parapharyngeal schwannomas.During surgical dissection,the tumors were found to be smooth and tough,without obvious adhesion to the surrounding tissues.The tumors were revealed to be a SFT following postoperative pathological analysis.CONCLUSION SFTs in the parapharyngeal space are rarely reported,and complete resection of such tumor is recommended.Adjuvant chemoradiotherapy is used in patients with extensive tumor invasion to lower the recurrence rate.Postoperative longterm follow-up is required.
文摘Extra-nasopharyngeal lymphoepithelioma-like carcinomas (LELC) are uncommon epithelial tumors. A few isolated case reports and series are available in literature involving the larynx, pharynx, salivary gland, lung etc., but involvement in the parapharyngeal space has not yet been reported. We aim to highlight one such case that has a clinical and radiological characteristic of a benign lesion whilst the histopathology reveals an infiltrating neoplasm. The typical clinical aggressiveness of a classical LELC of extra-nasopharyngeal lesion as described in literature is not present in our case. Also seen is an uncommon finding of abnormal branching of left external carotid artery. There is no standard treatment protocol for such a tumor;however, wide excision of this tumor in the parapharyngeal space via trans-cervical, trans-mandibular, trans-palatal approach has shown good and satisfactory tumor control of the primary site so far.
文摘Most of the parapharyngeal space tumours are benign.The primary treatment is complete resection of the tumour.Due to its location in the deep neck space,a pre-styloid tumour can be resected via the transoral approach.However,the surgical field is limited by the small oral cavity.With the use of rigid endoscopes,removing benign tumours through transoral approach in the parapharyngeal space is possible as they provide a broad and enlarged view of the confined space.Here,we report a case of a 64-year-old male with a giant pre-styloid parapharyngeal space tumour,who successfully underwent transoral endoscopic excision.Postoperatively,the patient had short hospital stay of total 3 days.His chewing and swallowing were not affected,and he resumed oral feeding prior to discharge.
文摘Synovial sarcoma is a rare soft tissue sarcoma of the head and neck region involving the parapharyngeal space.The diagnosis of synovial sarcoma can be very challenging to the pathologists.We present a rare case of parapharyngeal synovial sarcoma in a young female patient who had a two-month history of left cervical intumescent mass at level II.The fine needle aspiration cytology of the mass was proved inconclusive.Transcervical excision of the mass was performed and the first case of parapharyngeal sarcoma was identified in our center by fluorescence in situ hybridization(FISH) technique.Repeat imaging revealed residual tumor.The patient successfully underwent a second excision of the residual tumor and received adjuvant radiotherapy.
文摘Background:Several approaches have been described for the excision of parapharyngeal space tumors(PPSTs).Advances in endoscopy gave a further stimulus to the use of the transoral route.Aims:We present our experience with the endoscopy-assisted transoral approach(EATA)in this regard and a review of the most recent literature about EATA for PPSTs excision.Materials and Methods:We retrospectively analyzed our experience and systematically reviewed the literature about the outcomes of this technique.Results:Seven PPSTs were completely excised,with three of them requiring a combined transcervical approach.Only one case of postoperative wound dehiscence was registered,and the mean length of stay was 3.9 days.Final histopathological examination confirmed the results obtained with preoperative fine-needle aspiration biopsy in all cases and no recurrences were apparent after a mean follow-up of 28.1 months.Discussion:Magnetic resonance imaging,the modified Mallampati score and the 8 Ts criteria are useful instruments for the choice of the most appropriate surgical approach.Conclusion:In light of our experience and following other published series in the literature,we believe that EATA may represent a safe and effective approach for the treatment of the majority of PPSTs.
文摘Surge pressure caused by pipe moving through the wellbore full of drilling .fluid is the main factor affecting wellbore stability, on which the additional mud density isdesigned. Thus if is desired to predict the surge pressure with high accuracy. While this is closely, related with the selection of mud rheological models. Yield-Pseudoplastic model which has three parameters and is.famous for its higher accuracy has been used to describe the mud rheological properties in recent years. Based on this model the paper presents a new theoretical model for calculating surge pressure caused by mud viscosity during tripping or casing in a concentric annulus of directional wells under steady laminar situation. For convenience, the paper plots the distribution of the coefficients of surge pressure for different conditions. An example is given. These results provide the basis for controlling pressure surges and tripping velocity.
文摘The coexistence of acquired hemophilia A with a secondary retropharyngeal hematoma is an extremely unusual condition with important clinical implications. The purpose of this paper is to present a case involving a patient whose first clinical manifestation, namely dysphagia, along with specific clinical examination and imaging findings, led to an incorrect initial diagnosis of a retropharyngeal abscess. However, performance of a more thorough clinical examination led to the correct diagnosis of a hematoma secondary to acquired hemophilia A. This allowed surgery to be avoided in a patient at a high risk of bleeding. Conclusions: Acute neck masses require meticulous differential diagnosis assessing the possible presence of various causative systemic diseases before the most appropriate therapy can be determined.
文摘Objective:Parapharyngeal space contains intricate vascular anatomy(external and internal carotid arteries)that might be inadvertently injured during the dissection in this plane.None of the bony landmarks can be used during the transoral robotic surgery(TORS)radical tonsillectomy as these landmarks lie lateral to the internal carotid artery(ICA)and external carotid artery(ECA)in transoral approach.Our study aims to identify the safe surgical limits during the dissection of parapharyneal space in TORS radical tonsillectomy and to correlate the same with radiological study.Material and methods:Fifteen cadavers(30 head and neck regions)and 50 CT-Angiogram of neck(100 head and neck regions)were included in the anatomical and radiological study respectively.The vertical midpoint of anterior tonsillar pillar(palatoglossus muscle)was taken as the reference point and all the measurements were done at the level of reference point both for anatomical and radiological study.Distance between tonsillar fossa and ECA,distance between tonsillar fossa and ICA,relation between ECA and styloglossus and relation between ICA and stylopharyngeus at reference level were studied.Results:The mean distance of ECA from the tonsillar fossa at the reference point was 18.2 mm in the anatomical study and 16.2 mm in the radiological study.The mean distance of ICA from the tonsillar fossa was 23.4 mm and 23.3 mm in the anatomical study and radiological study.There was no significant difference between the anatomical and radiological findings for both the mean distance between ECA and ICA to the tonsillar fossa(p value was 0.45 and 0.30 respectively).ECA was located posterolateral to styloglossus in 24 cases(80.0%)and 79 cases(79.0%)in the anatomical and radiological study respectively.ICA was found posterolateral to stylopharyngeus in 21 cases(70.0%)and 69 cases(69.0%)in the anatomical and radiological study respectively.Conclusion:The muscular plane between styloglossus and stylopharyngeus can be used as an envelope to locate the ECA and ICA that lie medial to these critical vascular structures during TORS.We propose to divide the parapharyngeal space into two compartments(anterior and posterior)based on the surgical perspective of inside-out anatomy.The anterior compartment houses styloglossus muscle with ECA posterolateral to it and the posterior compartment has stylopharyngeus and ICA posterolateral to it.
