Plastic Tube Technique Research Articles

Clinical outcome of high-dose-rate interstitial brachytherapy in vulvar cancer: A single institutional experience

PurposeWith an aim to evaluate and report high dose date interstitial brachytherapy (HDR-ISBT) in vulvar cancers, we undertook this retrospective analysis. Methods and MaterialsHistologically proven vulvar cancers treated with HDR-ISBT between 2001 and 2016 were analyzed. Radiotherapy details, clinical outcome in terms of local control rates, survivals, and toxicities were evaluated. ResultsA total of 38 patients received HDR-ISBT, with definitive radiation in 29 (76.3%), adjuvant postoperative in six (15.8%) and salvage radiation in three (7.9%) patients. Of them, 29 patients received brachytherapy boost and nine patients ISBT alone. BT procedure included freehand plastic tube technique in 23 (single [n = 5] or multiple plane [n = 18]), 13 patients with template based and two patients combined approach. Patients with brachytherapy alone received median EQD2 of 38.4 Gy10 (35.5–46.7 Gy10), as boost received median 23.3 Gy10 (13–37.3 Gy10). At 3-month post-treatment response evaluation, 30 patients achieved clinically complete response, two patients partial response and six maintained postoperative status. With a median follow-up of 30 months, 29 (76.3%) were disease free, and 9 (23.7%) patients had relapsed disease with four patients expired due to disease and two died of other causes. The 5-year overall survival, disease free survival, and local control rates were 82%, 51%, and 77%, respectively. ConclusionsHDR-ISBT in vulvar cancer is a feasible and a viable option with acceptable and comparable outcomes.

Hyperfractionated high-dose rate brachytherapy in the treatment of oral tongue cancer

Background Low-dose rate brachytherapy is a well established treatment modality of oral cancer. Data about high-dose rate (HDR) brachytherapy are still sparse with various fractionation schedules and heterogeneous results. Aim The aim of our retrospective study was to evaluate the results of HDR brachytherapy with doses of 3 Gy twice daily. Patients and methods Twenty patients with squamous cell tongue cancer were treated in the years 2001–2009 by exclusive HDR BT 18 × 3 Gy twice daily. The plastic tube technique was used. Median follow up was 47 months (7.8–118) since brachytherapy. Results The local and locoregional control was 85% and 68%, respectively. Bone necrosis developed in one case treated without mandibular shielding and soft tissue necrosis in 2 cases. Conclusion It can be concluded that HDR brachytherapy with 18 × 3 Gy twice daily is safe with promising local control. The risk of nodal recurrences is substantial.

Penile brachytherapy: Results for 49 patients

To report results for 49 men with squamous cell carcinoma (SCC) of the penis treated with primary penile interstitial brachytherapy at one of two institutions: the Ottawa Regional Cancer Center, Ottawa, and the Princess Margaret Hospital, Toronto, Ontario, Canada. From September 1989 to September 2003, 49 men (mean age, 58 years; range, 22-93 years) had brachytherapy for penile SCC. Fifty-one percent of tumors were T1, 33% T2, and 8% T3; 4% were in situ and 4% Tx. Grade was well differentiated in 31%, moderate in 45%, and poor in 2%; grade was unspecified for 20%. One tumor was verrucous. All tumors in Toronto had pulsed dose rate (PDR) brachytherapy (n = 23), whereas those in Ottawa had either Iridium wire (n = 22) or seeds (n = 4). Four patients had a single plane implant with a plastic tube technique, and all others had a volume implant with predrilled acrylic templates and two or three parallel planes of needles (median, six needles). Mean needle spacing was 13.5 mm (range, 10-18 mm), mean dose rate was 65 cGy/h (range, 33-160 cGy/h), and mean duration was 98.8 h (range, 36-188 h). Dose rates for PDR brachytherapy were 50-61.2 cGy/h, with no correction in total dose, which was 60 Gy in all cases. Median follow-up was 33.4 months (range, 4-140 months). At 5 years, actuarial overall survival was 78.3% and cause-specific survival 90.0%. Four men died of penile cancer, and 6 died of other causes with no evidence of recurrence. The cumulative incidence rate for never having experienced any type of failure at 5 years was 64.4% and for local failure was 85.3%. All 5 patients with local failure were successfully salvaged by surgery; 2 other men required penectomy for necrosis. The soft tissue necrosis rate was 16% and the urethral stenosis rate 12%. Of 8 men with regional failure, 5 were salvaged by lymph node dissection with or without external radiation. All 4 men with distant failure died of disease. Of 49 men, 42 had an intact and tumor-free penis at last follow-up or death. The actuarial penile preservation rate at 5 years was 86.5%. Brachytherapy is an effective treatment for T1, T2, and selected T3 SCC of the penis. Close follow-up is mandatory because local failures and many regional failures can be salvaged by surgery.

Real-size CT Slices to Optimize Brachytherapy in the Plastic Tube Technique for Oral Cavity Neoplasms

To optimize brachytherapy treatments in the plastic tube technique and to have a quality assurance system, we use Real-Size CT slices (RSCTS). This procedure permits us to have a more precise knowledge of the dose distribution in the tumor and in the healthy neighboring tissues.

Brachytherapy of squamous cell carcinoma of the nasal vestibule.

From 1985 to 1994, 23 patients with squamous cell carcinoma of the nasal vestibule were treated by brachytherapy. The TNM stage was as follows: T1N0 (9 patients), T2N0 (11 patients) and T4N0 (3 patients). Four patients had primary surgery and postoperative brachytherapy, whereas 12 patients had brachytherapy alone and 7 had tele- and brachytherapy in combination. For brachytherapy, the plastic tube technique was used. With the exception of one patient with a partial response, complete response was obtained in all patients. Two patients relapsed: one (T4N0) locally after 5 months and one (T2N0) regionally after 12 months. Both are alive and with no evidence of disease after salvage surgery. For early stage carcinoma (T1, T2) of the nasal vestibule, brachytherapy is a safe treatment yielding a high grade of local control and with good cosmetic results.

Place de l'endocuriethérapie par iridium 192 dans l'irradiation exclusive des carcinomes épidermoïdes T1–T2 de l'arche véloamygdalienne

We have reviewed the results of 165 T1 and T2 squamous cell carcinomas of the faucial arch treated by definitive irradiation including or not iridium 192 brachytherapy to ascertain whether a significant relationship exists between iridium implantation, local control, complications and survival. From March 1971 to November 1990, 58 T1 and 107 T2 (NO: 107/165; N1: 30/165; N2: 9/165; N3: 19/165) biopsy proven squamous cell carcinomas of the tonsillar region (104/165) and the soft palate and uvula (61/165) were treated in the Henri Mondor Hospital by definitive irradiation with curative intent. From 1971 to 1981 (period 1), only guide gutter technique was available, so that implants were reserved for small tumors: patients were either managed by definitive telecobaltherapy to tumor site and neck node areas (group I; n = 48; mean dose: 70 Gy; confidence interval: +/- 5.5, 5 fractions of 1.8 Gy per week) or by exclusive iridium implant (group 2; n = 11; all T1NO; 64 Gy +/- 4.8) or by a combination of external beam radiation therapy to tumor site and neck nodes areas and iridium implant (group 3; n = 40). In 1981 (period 2), a new plastic tube technique, which enables implantation of larger areas, was introduced and all patients (group 4; n = 66) were then managed by external radiation therapy (group 3 + 4: 47 Gy +/- 4.3) followed by an iridium implant (31 Gy +/- 10.5). Clinically positive neck nodes either received additional external dose with electrons or were excised. Overall 5-year survival (Kaplan Meier) was 23%, 50.5%, and 60% in groups 1, 2 and 3 + 4, respectively (p < 0.001, log rank). Five-year local control was 58%, 100%, and 91%, respectively (p < 0.001). Five-year necrosis rate was 10%, 25% and 30%, respectively (NS). Comparison of results between the two periods of the study (group 1 + 2 + 3 vs group 4) shows that these two groups are statistically comparable according to site and size of tumor and N status and that both local control (77% vs 94% at 5 years; p < 0.01) and disease free survival (56% vs 71%; p = 0.03) were improved after 1980, while there was a trend to an increase in overall survival (42% vs 53% at 5 years; p = 0.08); nodal control (86% vs 95% at 5 years) and necrosis rate (11% vs 20% at 5 years) were not modified. Multivariate analysis showed that both local control (p < 0.0001) and overall survival (p < 0.0001) were improved when tumor was implanted. We recommend then to treat T1 and T2 squamous cell carcinomas of the faucial arch by external radiation therapy to tumor site and neck areas (45 Gy/25 fractions/5 weeks) followed by a 30 Gy iridium implant and, for patients with clinically positive nodes, either a further 25-30 Gy electron beam irradiation to the nodes or neck node dissection.

Epidermoid carcinomas of the floor of mouth treated by exclusive irradiation: Statistical study of a series of 207 cases

Purpose. Our aim was to study the results and the complications of this series of 207 patients treated from 1976 to 1992 and to compare them with the results of the literature. Material and methods. The treatment consisted of a combination of external beam irradiation (EBI) (to the tumor and the node areas) and complementary brachytherapy to the primary tumor in 105 cases. In 102 cases, brachytherapy only was delivered to the tumor with or without neck dissection of the node areas. The brachytherapy was performed mostly with the hairpin technique in the beginning (in 61 cases) and subsequently the plastic tube technique with indium wires. The dosimetry followed the Paris system rules. There were 41% T1, 48% T2, 8% T3, 2% T4 and 1% Tx with 83% N0, 12% N1, 3% N2, 2% N3. Ninety-one percent of patients were male and 9% were female. Results. The local control at 5 years is 97, 72 and 51%, respectively, for T1, T2, T3. The specific survival (without the patients dead of intercurrent disease or second cancer) was 88, 47 and 36%, and the overall survival at 5 years was 71, 42 and 35%. Of note, approximately one third of patients died of intercurrent disease or second cancers (70 patients = 34%). Significant factors that can influence the results are: for local control, the size of the lesion T1/T2/T3 (p < 0.0001); for the locoregional control, the absence of node involvement. The following factors are not significant: age and sex (age significant for survival). The significant treatment factors are the safety margin (p < 0.0003), brachytherapy only on T for T2N0 (p = 0.01). A total duration of treatment of less than 50 days is also significant. The spacing and the total dose (higher dose for large tumors) were not found to be significant. The complications were classified into four grades: grade 1,17% (median healing, 2 months for soft tissue complications and 5 months for bone complications); grade 2, 12%; grade 3, 6% (frequently requiring surgical resection); grade 4, 0.5% (death, one case). In this series, for the complications, the dose rate, the spacing and the total dose were found not to be significant. Conclusion. Carcinomas of the floor of mouth treated by exclusive irradiation have a rather good prognosis and the number of grade 2 and 3 complications remains acceptable. Exclusive brachytherapy is preferable to the combination of EBI plus brachytherapy for T1T2N0.

205 Quality control in brachytherapy (BT) treatments for head and neck neoplasms

To optimize BT in plastic tube technique for oral carcinomas we use real size CT slices (RSCTS). The day after the implant, the patients are referred to the radiology department with CT hyperdense dummy sources in the plastic tubes. Some RSCTS are performed to study the real relationship between the sources and to know the real distance to the neighborhood structures. After the dosimetric study is made, we know the dose distribution in the area of the implant and the dose in the healthy tissues. Some RSCTS are performed the last day, after treatment is finished. This allows us knowledge of variations in the dose distribution during the treatment time. We report our results.

Epidermoid carcinomas of the floor of mouth treated by exclusive irradiation: statistical study of a series of 207 cases

Purpose. Our aim was to study the results and the complications of this series of 207 patients treated from 1976 to 1992 and to compare them with the results of the literature. Material and methods. The treatment consisted of a combination of external beam irradiation (EBI) (to the tumor and the node areas) and complementary brachytherapy to the primary tumor in 105 cases. In 102 cases, brachytherapy only was delivered to the tumor with or without neck dissection of the node areas. The brachytherapy was performed mostly with the hairpin technique in the beginning (in 61 cases) and subsequently the plastic tube technique with indium wires. The dosimetry followed the Paris system rules. There were 41% T1, 48% T2, 8% T3, 2% T4 and 1% Tx with 83% N0, 12% N1, 3% N2, 2% N3. Ninety-one percent of patients were male and 9% were female. Results. The local control at 5 years is 97, 72 and 51%, respectively, for T1, T2, T3. The specific survival (without the patients dead of intercurrent disease or second cancer) was 88, 47 and 36%, and the overall survival at 5 years was 71, 42 and 35%. Of note, approximately one third of patients died of intercurrent disease or second cancers (70 patients = 34%). Significant factors that can influence the results are: for local control, the size of the lesion T1/T2/T3 ( p < 0.0001); for the locoregional control, the absence of node involvement. The following factors are not significant: age and sex (age significant for survival). The significant treatment factors are the safety margin ( p < 0.0003), brachytherapy only on T for T2N0 ( p = 0.01). A total duration of treatment of less than 50 days is also significant. The spacing and the total dose (higher dose for large tumors) were not found to be significant. The complications were classified into four grades: grade 1,17% (median healing, 2 months for soft tissue complications and 5 months for bone complications); grade 2, 12%; grade 3, 6% (frequently requiring surgical resection); grade 4, 0.5% (death, one case). In this series, for the complications, the dose rate, the spacing and the total dose were found not to be significant. Conclusion. Carcinomas of the floor of mouth treated by exclusive irradiation have a rather good prognosis and the number of grade 2 and 3 complications remains acceptable. Exclusive brachytherapy is preferable to the combination of EBI plus brachytherapy for T1T2N0.

Place of iridium 192 implantation in definitive irradiation of faucial arch squamous cell carcinomas

Purpose : We have reviewed the results of 165 T1 and T2 squamous cell carcinomas of the faucial arch treated by definitive irradiation including or not Iridium 192 brachytherapy to ascertain whether a significant relationship existed between Iridium implantation, local control, complications, and survival. Methods and Materials: From March 1971 to November 1990, 58 T1 and 107 T2 (NO: 107 165 ; N1: 30 165 ; N2: 9 165 ; N3: 19 165 ) biopsy proven squamous cell carcinomas of the tonsillar region ( 104 165 ) and the soft palate and uvula ( 61 165 ) were treated in Henri Mondor Hospital by definitive irradiation with curative intent. From 1971 to 1981 (period 1), only guide gutter technique was available, so that implants were reserved for small tumors: patients were either managed by definitive telecobaltherapy to tumor site and neck node areas (Group 1; n = 48; mean dose: 70 Gy; confidence interval: ±5.5; 5 fractions of 1.8 Gy per week) or by exclusive Iridium implant (Group 2; n = 11; all T1 NO; 64 Gy ± 4.8) or by a combination of external beam radiation therapy to tumor site and neck nodes areas and Iridium implant (Group 3; n = 40). In 1981 (Period 2), a new plastic tube technique, which enables implantation of larger areas, was introduced in the department and all patients (Group 4; n = 66) were then managed by external radiation therapy (Group 3 + 4 : 47 Gy ± 4.3) followed by an Iridium implant (31 Gy ± 10.5). Clinically positive neck nodes either received additional external dose with electrons or were excised. Results : Overall 5-year survival (Kaplan Meier) was 21%, 50.5%, and 60% in groups 1, 2, and 3 + 4, respectively ( p < 0.001, log rank). Five-year local control was 58%, 100%, and 91%, respectively ( p < 0.001). Five-year necrosis rate was 4.5%, 20.5% and 18%, respectively (N.S.). Comparison of results between the two periods of the study (Group 1 + 2 + 3 vs. group 4) show that these two groups are statistically comparable according to site and size of tumor and N status and that both local control (77% vs. 94% at 5 years; p < 0.01) and disease-free survival (56% vs. 71%; p = 0.03) were improved after 1980, while there was a trend to an increase in overall survival (42% vs. 53% at 5 years; p = 0.08); nodal control (86% vs. 95% at 5 years), and necrosis rate (11% vs. 20% at 5 years) were not modified. Multivariate analysis showed that both local control ( p < 0.0001) and overall survival ( p < 0.0001) were improved when tumor was implanted. Conclusion : We recommend then to treat T1 and T2 squamous cell carcinomas of the faucial arch by external radiation therapy to tumor site and neck areas (45 Gy/25 fractions/5 weeks) followed by a 30 Gy Iridium implant and, for patients with clinically positive nodes, either a further 25–30 Gy electron beam irradiation to the nodes or neck node dissection.

Conservative treatment for lower gynecological tract malignancies in childrin and adolescents: The Institut Gustave-Roussy experience

Between 1972 and 1986, 37 patients with lower genital tract malignancies were treated with intracavitary or interstitial brachytherapy. Thirteen patients presented with clear cell adenocarcinoma, 14 patients with embryonal rhabdomyosarcoma, 6 patients with endodermal sinus tumor, 3 patients with sarcoma, and I patient with an undifferentiated tumor. FIGO classification was: Stage I, 16%; Stage II, 47%; and Stage III, 37%. Treatment policy included initial exploratory laparotomy with lymph node biopsy and ovarian transposition, chemotherapy (except in clear cell adenocarcinoma) and/or external radiotherapy prior to interstitial brachytherapy. Chemotherapy consisted of a combination of VAC-Ad (V = vincristine, A = D actinomycin, C = cyclophosphamide, Ad = adriamycin) in rhabdomyosarcoma and sarcomas, and MAC-Ad (M = methotrexate) in endodermal sinus tumor. External radiotherapy was used in seven patients: in one to reduce a bulky clear cell adenocarcinoma (20 Gy) and in six for pelvic nodal involvement (45 Gy). Brachytherapy techniques depended on tumor site and extent, and on the anatomy of the patients. Vulvar tumors were implanted with iridium-192 wires by an afterloading plastic tube technique. Cervical and vaginal tumors were treated with individually tailored moulded vaginal applicators loaded with either cesium-137 or iridium-192, with or without interstitial implants by plastic tube or guide gutter technique. Computerized dosimetry allowed calculation of treatment volumes and doses delivered on the tumor and adjacent critical organs. The prescribed dose (including external radiotherapy) was 60–75 Gy with 1–3 brachytherapy applications of a low dose rate (0.2 Gy/hr). Six patients are dead: one from chemotherapy complication, three of metastases (two sarcomas, one endodermal sinus tumor) and two of pelvic failures and metastases (two clear cell adenocarcinoma). The overall disease free 5-year survival is 72%. Actuarial 5-year local control is 84%, but including salvage is 94%: three (two rhabdomyosarcoma, one clear cell adenocarcinoma) of the five local failures were salvaged by surgery, chemotherapy and/or brachytherapy. Metastases occurred in six patients, one (sarcoma) salvaged by chemotherapy and external radiotherapy. Complications requiring surgery occurred in five patients: two hydronephroses, one urethral stricture, one ileo-cecal obstruction, and one vesicovaginal fistula. Twelve of the 17 patients (7l%) over 12 years of age are normally menstruating. Two patients have produced three normal children. This multidisciplinary management of lower gynecological tract tumors including brachytherapy is both conservative and effective.

The utilization of I-125 seeds as a substitute for Ir-192 seeds in temporary interstitial implants: An overview and a description of the william beaumont hospital technique

In August of 1986, the Department of Radiation Oncology at William Beaumont Hospital (WBH) initiated the routine use of high activity 1–125 seeds as a substitute for Ir-192 seeds in temporary implants where the afterloading plastic tube technique was used. Through March 6, 1987, 42 temporary 1–125 implants were performed as a boost for curative therapy (38 breasts, 2 sarcomas, 2 tongues). Thus far, we have observed no differences in acute toxicity. Sources ranging from 2 to 5 mCi were utilized. The advantages of 1–125 are as follows: (a) Easy to shield; (b) Radiation safety; (c) Decreased exposure to sensitive organs in close proximity to the implanted site; (d) Dosimetric advantages both intrinsic and extrinsic; and (e) Any private room can be used for these patients allowing a central brachytherapy ward to be established. While the advantages were obvious, we anticipated potential disadvantages and shortcomings and these will be discussed in detail. Furthermore because of significant differences in tube and ribbon construction, the 1–125 afterloading plastic tube technique has important differences from that technique used with Ir-192. These modifications must be fully understood to maintain the integrity of the I-125 seed-ribbon afterloading tube assembly. A detailed description of the technique will be emphasized.

Interstitial and external radiotherapy in carcinoma of the soft palate and uvula

Forty-three patients, all male, with limited epidermoid carcinoma of the soft palate and uvula were treated by interstitial implant usually associated with external radiotherapy. Most patients received 50 Gy external irradiation to the oropharynx and neck followed by 20–35 Gy by interstitial iridium-192 wires using either guide gutters or a plastic tube technique. Twelve primary tumors and two recurrences after external irradiation alone had implant only for 65–75 Gy. Total actuarial local control is 92% with no local failures in 34 T, primary tumors. Only one serious complication was seen. Overall actuarial survival was 60% at 3 years and 37% at 5 years but causespecific survivals were 81% and 64%. The leading cause of death was other aerodigestive cancer, with an actuarial rate of occurrence of 10% per year after treatment of a soft palate cancer. Interstitial brachytherapy alone or combined with external irradiation is safe, effective management for early carcinoma of the soft palate and uvula but second malignancy is a serious problem.

Definitive radiation treatment for early stage carcinoma of the soft palate and uvula: The indications for iridium 192 implantation

From 1971 to 1984 59 T1 and T2 carcinomas of the soft palate and uvula were treated definitively by irradiation at the Henri Mondor hospital. Included are ten patients previously irradiated to the oropharyngeal area for either a carcinoma of the soft palate or another malignancy. Sixteen patients were treated by external irradiation alone, 14 by Iridium 192 implantation, and 29 by a combination of the two. Two techniques of implantation were used: the guide gutter technique (33 patients) and the plastic tube technique (10 patients). Clinically negative neck nodes ( 51 59 ) either received prophylactic telecobalt therapy ( 39 51 ) or were surveilled ( 12 51 ). Clinically involved nodes ( 8 59 ) were managed either by external irradiation alone ( 4 8 ) or combined with neck dissection ( 4 8 ). Local failure was 25% ( 4 16 ) after exclusive telecobalt therapy, 18% ( 5 19 ) after combined telecobalt therapy and implantation, and 0% ( 0 14 ) after Iridium 192 implantation alone. No local failures were seen with the plastic tube technique ( 0 10 ) as compared to 15% ( 5 33 ) for guide gutters. Only two nodal failures were observed ( 2 59 ): 3%). Crude 5-year disease-free survival was 33%. Severe complications were limited to one osteonecrosis, one soft tissue necrosis, and one partial palatal incompetence. Salivary impairment was reduced when implantation was used for part or all of the treatment. We recommend 45 Gy external radiation followed by 30 Gy from Iridium 192 implantation using the plastic tube method unless there has been prior oropharyngeal irradiation, in which case we give 60 Gy from implantation alone. For clinically negative neck nodes, we recommend 45 Gy prophylactic external neck irradiation. For clinically positive lymph nodes, this should be followed by either a 25 to 30 Gy boost to the involved nodes or a neck dissection.

Concentration and identification of Cryptosporidium sp. by use of a parasite concentrator.

A new disposable plastic tube device and technique for ovum and parasite concentration, with upper and lower chambers separated by a fine screen, was compared with the standard gauze and open-funnel filtration technique as well as with the technique of direct smearing with an acid-fast stain. The new concentrator was distinctly superior to gauze filtration in concentrating Cryptosporidium sp. oocysts. Processing time was reduced. The new technique was less messy and as a closed system was considered to be much safer than gauze filtration.

A plastic tube technique for direct vision of endodontic procedures

A technique for the direct visualization of endodontic procedures utilizing clear plastic tubes machined to simulate root canals is described. The visualization of endodontic procedures allows for their evaluation by the clinician as well as their use as an adjunct to didactic courses in endodontics. During mechanical instrumentation it is evident that a concerted effort must be made to debride all of the walls of a canal. Hydraulic forces are seen to play a major role in irrigation and in applying root canal cement. The technique also reveals voids in the completed root canal filling when verticle condensation is used to obturate the canals.

Solid-phase radioimmunoassay of insulin.

ABSTRACT A solid-phase radioimmunoassay of insulin was developed using the plastic tube technique in which the inner walls of the tubes were coated with insulin antibodies. The binding of 125I-insulin to the adsorbed antibody was shown to be quantitatively inhibited with the non-radioactive insulin present in the samples tested. The optimal conditions were determined for a) labelling of small amounts (3 μg) of insulin with radioactive iodine, b) coating of plastic tubes with insulin antisera and γ-globulin fractions, c) the stability of coated tubes with insulin antibodies and d) radioimmunoassay of insulin. The reproducibility of the coated test tube technique for insulin determination is adequate from a clinical point of view and the ease with which this test is performed is advantageous from a practical point of view.

Plastic-tube technique for coring unconsolidated wet sand; a discussion

Plastic-tube technique for coring unconsolidated wet sand; a discussion

Notched plastic tube for stapes mobilization.

In spite of excellent results with stapedeotomy and grafting, the plastic tube technique for stapes mobilization still remains a very useful procedure in cases where there is some portion of the footplate left which is not involved by the otosclerosis. Complete closure of the air-bone gap is quite common, the procedure is relatively simple, and one does not commit oneself ultimately as is the case with stapedectomy. Plastic tubes, however—as every otosurgeon will agree— may be tricky and behave in quite an erratic way Fig. 1.—The notch is made at the upper end of the tube on the beveled side. It should be a little less than 1 mm. deep. Cutting against the pick in the tube makes it easier. in the oval window niche. Lifting the long process of the incus (hooks, threads) helps a good deal, but it requires both hands and there is the inherent danger of